A Phase 3, Multicenter, Randomized, Double-Blind Study With an Active-Controlled Initial Treatment Period Followed by a Dose-Blind Maintenance Treatment Period to Evaluate the Efficacy and Safety of Bimekizumab in Adult Subjects With Moderate to Severe Chronic Plaque Psoriasis
Phase: PHASE3
Conditions: Chronic Plaque Psoriasis, Moderate to Severe Plaque Psoriasis
Sponsor: UCB Biopharma SRL

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Clinical Study Protocol 
Bimekizumab 
PS0008 
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PROTOCOL PS0008 AMENDMENT 2 
A PHASE 3, MULTICENTER, RANDOMIZED, DOUBLE-BLIND 
STUDY WITH AN ACTIVE-CONTROLLED INITIAL TREATMENT 
PERIOD FOLLOWED BY A DOSE-BLIND MAINTENANCE 
TREATMENT PERIOD TO EVALUATE THE EFFICACY AND 
SAFETY OF BIMEKIZUMAB IN ADULT SUBJECTS WITH 
MODERATE TO SEVERE CHRONIC PLAQUE PSORIASIS 
PHASE 3 
EudraCT Number: 2016-003392-22 
IND Number: 128707 
Sponsor: 
UCB Biopharma SPRL 
Allée de la Recherche 60 
1070 Brussels 
BELGIUM 
Protocol/Amendment number 
Date 
Type of amendment 
Final Protocol 
15 Aug 2017 
Not applicable 
Protocol Amendment 1 
15 Oct 2017 
Not applicable 
Protocol Amendment 2 
06 Apr 2018 
Substantial 
Confidential Material 
Confidential 
This document is the property of UCB and may not – in full or in part – be passed on, 
reproduced, published, or otherwise used without the express permission of UCB. 
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STUDY CONTACT INFORMATION 
Sponsor 
UCB Biopharma SPRL 
Allée de la Recherche 60 
1070 Brussels 
BELGIUM 
Sponsor Study Physician 
Name: 
Nancy Cross, MD 
Address: 
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, 
NC 27617 
Phone: 
+1 919 767 1060 
Fax: 
+1 919 767 2570 
Clinical Project Manager 
Name: 
Petrina Wall 
Address: 
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, 
NC 27617 
Phone: 
+1 919 767 2613 
Fax: 
+1 919 767 2570 
Clinical Trial Biostatistician 
Name: 
Maggie Wang 
Address: 
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, 
NC 27617 
Phone: 
 +1 919 767 2877 
Fax: 
+1 919 767 2570 
Clinical Monitoring Contract Research Organization 
Name: 
PAREXEL International (IRL) Limited-Ireland 
Address: 
Ireland Limited at 70 Sir John Rogerson’s Quay, Dublin 2, 
Ireland 
Phone: 
+353 (1) 477 3171 
Fax: 
+353 (1) 477 3308 
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SERIOUS ADVERSE EVENT REPORTING 
Serious adverse event reporting (24h) 
Fax 
Europe and Rest of the World: +32 2 386 24 21 
USA and Canada: +1 800 880 6949 or +1 866 890 3175  
Email 
Global: DS_ICT@ucb.com  
 
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TABLE OF CONTENTS 
LIST OF ABBREVIATIONS .................................................................................................. 10 
1 
SUMMARY ..................................................................................................................... 14 
2 
INTRODUCTION ........................................................................................................... 15 
2.1 Psoriasis ........................................................................................................................... 15 
2.1.1 
Global epidemiology of psoriasis ........................................................................ 15 
2.1.2 
Current treatments for psoriasis ........................................................................... 16 
2.2 Bimekizumab ................................................................................................................... 18 
2.2.1 
Clinical ................................................................................................................. 18 
2.2.1.1 
Completed studies .......................................................................... .......... 18 
2.2.1.2 
Ongoing studies ........................................................................ .............. 20 
2.2.2 
Nonclinical ................................................................................... .. ................... 20 
3 
STUDY OBJECTIVE(S) ...................................................................... .......................... 21 
3.1 Primary objective ............................................................................. ............................... 21 
3.2 Secondary objectives ............................................................... . ..................................... 21 
3.3 Other objectives .................................................................. ............................................ 21 
4 
STUDY VARIABLES ....................................... . ........ ................................................ 22 
4.1 Primary efficacy variable ...................................... .. . ..................................................... 22 
4.2 Secondary variables ................................ . .. .... . ............................................................ 22 
4.2.1 
Secondary efficacy variables .... ..... . ................................................................. 22 
4.2.2 
Secondary safety variables ......... ...................................................................... 22 
4.3 Other variables ................................. . ............................................................................. 22 
4.3.1 
Other efficacy variables ..... ................................................................................. 22 
4.3.2 
Other safety variables . ........................................................................................ 24 
4.3.3 
Pharmacokinetic variable ..................................................................................... 24 
4.3.4 
Pharmacogenomic variables ................................................................................ 24 
4.3.5 
Immunological variable ....................................................................................... 24 
5 
STUDY DESIGN ............................................................................................................. 24 
5.1 Study description ............................................................................................................. 24 
5.2 Study periods ................................................................................................................... 25 
5.2.1 
Screening Period .................................................................................................. 25 
5.2.2 
Double-blind Initial Treatment Period ................................................................. 25 
5.2.4 
Safety Follow-Up Period ..................................................................................... 26 
5.2.5 
Premature End of Treatment ................................................................................ 26 
5.3 Study duration per subject................................................................................................ 27 
5.4 Planned number of subjects and site(s) ............................................................................ 27 
5.5 Anticipated regions and countries .................................................................................... 27 
5.6 Schedule of study assessments ......................................................................................... 27 
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5.7 Schematic diagram ........................................................................................................... 33 
5.8 Rationale for study design and selection of dose ............................................................. 34 
5.8.1 
Study design ......................................................................................................... 34 
5.8.2 
Dose selection ...................................................................................................... 34 
6 
SELECTION AND WITHDRAWAL OF SUBJECTS ................................................... 34 
6.1 Inclusion criteria .............................................................................................................. 34 
6.2 Exclusion criteria ............................................................................................................. 35 
6.3 Withdrawal criteria .......................................................................................................... 38 
6.3.1 
Potential drug-induced liver injury IMP discontinuation criteria ........................ 40 
7 
STUDY TREATMENT(S) ..................................................................................... . ...... 41 
7.1 Description of investigational medicinal product(s) ......................................... .............. 41 
7.2 Treatment(s) to be administered ................................................................. .................... 42 
7.3 Packaging ............................................................................................ ... ........................ 44 
7.4 Labeling .......................................................................................... . ............................. 44 
7.5 Handling and storage requirements.......................................... . . ................................... 44 
7.6 Drug accountability .......................................................................................................... 44 
7.7 Procedures for monitoring subject compliance .... . .. ..... . . ............................................ 45 
7.8 Concomitant medication(s)/treatment(s)................... ...................................................... 45 
7.8.1 
Permitted concomitant treatments (medications and therapies) .......................... 45 
7.8.1.1 
Topical medications ......... ...... ................................................................. 45 
7.8.1.2 
Other medications ..... .......... .................................................................... 45 
7.8.2 
Prohibited concomitant treatments (medications and therapies) ......................... 46 
7.8.2.1 
Vaccines ................ .................................................................................. 47 
7.9 Blinding ................................... ........................................................................................ 47 
7.9.1 
Procedures for maintaining and breaking the treatment blind ............................. 48 
7.9.1.1 
Maintenance of IMP blind ......................................................................... 48 
7.9.1.2 
Breaking the treatment blind in an emergency situation ........................... 48 
7.10 Randomization and numbering of subjects ...................................................................... 48 
8 
STUDY PROCEDURES BY VISIT ............................................................................... 48 
8.1 Screening Visit (2 to 5 weeks) ......................................................................................... 49 
8.2 Initial Treatment Period ................................................................................................... 50 
8.2.1 
Baseline Visit ....................................................................................................... 50 
8.2.2 
Week 1 (±3 days) ................................................................................................. 51 
8.2.3 
Week 3 (±3 days) ................................................................................................. 52 
8.2.4 
Week 4 (±3 days) ................................................................................................. 53 
8.2.5 
Week 5 and 7 (±3 days) ....................................................................................... 53 
8.2.6 
Week 8 (±3 days) ................................................................................................. 54 
8.2.7 
Week 9 and 11 (±3 days) ..................................................................................... 55 
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8.2.8 
Week 12 (±3 days) ............................................................................................... 55 
8.2.9 
Week 13 and 15 (±3 days) ................................................................................... 56 
8.2.10 
Week 16 (±3 days) ............................................................................................... 56 
8.3 Dose-blind Maintenance Treatment Period ..................................................................... 57 
8.3.1 
Week 17 and 19 (±3 days) ................................................................................... 57 
8.3.2 
Week 20 (±3 days) ............................................................................................... 58 
8.3.3 
Week 21 and 23 (±3 days) ................................................................................... 59 
8.3.4 
Week 24 (±3 days) ............................................................................................... 59 
8.3.5 
Week 28 (±7 days) ............................................................................................... 60 
8.3.6 
Week 32 (±7 days) ...................................................................................... . ...... 61 
8.3.7 
Week 36 (±7 days) ................................................................................ .............. 61 
8.3.8 
Week 40 (±7 days) .......................................................................... .................... 62 
8.3.9 
Week 44 (±7 days) .................................................................. ... ........................ 63 
8.3.10 
Week 48 (±7 days) .............................................................. . ............................. 63 
8.3.11 
Week 52 (±7 days) ....................................................... . . ................................... 64 
8.3.12 
Week 56 (±7 days) ............................................................................................... 65 
8.4 Premature End of Treatment Visit ....................... . .. ..... . . ............................................ 66 
8.5 Safety Follow-Up Visit (20 weeks after final dose ±7 days) ........................................... 67 
8.6 Unscheduled Visit ..................................... .. ...... .. ......................................................... 67 
9 
ASSESSMENT OF EFFICACY ............. ...... ................................................................. 67 
9.1 Psoriasis Area and Severity Index .. .......... .................................................................... 68 
9.2 Investigator’s Global Assessment ...... . . ......................................................................... 68 
9.3 Dermatology Life Quality Index .. .................................................................................. 69 
9.4 Patient Health Questionnaire 9 ........................................................................................ 69 
9.5 Scalp IGA .......................... .............................................................................................. 69 
9.6 mNAPSI ........................................................................................................................... 70 
9.7 pp-IGA ................... ... ..................................................................................................... 70 
9.8 Euro Quality of Life 5-Dimensions, 3-Level ................................................................... 71 
9.9 Short Form 36-Item Health Survey .................................................................................. 71 
9.10 Patient Global Assessment of psoriasis ........................................................................... 72 
9.11 Patient Symptom Diary responses ................................................................................... 72 
9.12 sPASE questionnaire ........................................................................................................ 72 
9.13 PGADA for the arthritis visual analog scale .................................................................... 72 
9.14 WPAI-SHP V2.0 .............................................................................................................. 73 
10 ASSESSMENT OF PHARMACOKINETIC AND PHARMACOGENOMIC 
VARIABLE(S) ................................................................................................................ 73 
10.1 Pharmacokinetic variables ............................................................................................... 73 
10.2 Pharmacogenomic variables ............................................................................................ 73 
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11 ASSESSMENT OF IMMUNOLOGICAL VARIABLE(S) ............................................ 74 
12 ASSESSMENT OF SAFETY .......................................................................................... 74 
12.1 Adverse events ................................................................................................................. 74 
12.1.1 
Definitions ........................................................................................................... 74 
12.1.1.1 
Adverse event ............................................................................................ 74 
12.1.1.2 
Serious adverse event ................................................................................ 75 
12.1.1.3 
Adverse events of special interest ............................................................. 76 
12.1.1.4 
Other safety topics of interest .................................................................... 76 
12.1.2 
Procedures for reporting and recording adverse events ....................................... 76 
12.1.2.1 
Description of adverse events ........................................................... . ...... 76 
12.1.2.2 
Rule for repetition of an adverse event....................................... .............. 77 
12.1.2.3 
Additional procedures for reporting serious adverse events .................... 77 
12.1.3 
Follow up of adverse events ................................................... ... ........................ 78 
12.1.4 
Pregnancy ........................................................................... . ............................. 78 
12.1.5 
Suspected transmission of an infectious agent via a medicinal product .............. 79 
12.1.6 
Overdose of investigational medicinal product ................................................... 79 
12.1.7 
Safety signal detection ............................. . .. ..... . . ............................................ 79 
12.2 Laboratory measurements ......................................... ...................................................... 80 
12.2.1 
Evaluation of PDILI ..................... .. ...... .. ......................................................... 81 
12.2.1.1 
Consultation with Medical Monitor and local hepatologist ...................... 85 
12.2.1.2 
Immediate action: determination of IMP discontinuation ......................... 85 
12.2.1.3 
Testing: identification/exclusion of alternative etiology ........................... 85 
12.2.1.4 
Follow-up evaluation ................................................................................. 87 
12.3 Other safety measurements ..... ........................................................................................ 88 
12.3.1 
Assessment and management of TB and TB risk factors .................................... 88 
12.3.1.1 
Tuberculosis assessment by IGRA ............................................................ 91 
12.3.1.2 
Chest x-ray for tuberculosis ...................................................................... 91 
12.3.1.3 
Tuberculosis questionnaire ........................................................................ 91 
12.3.1.4 
Tuberculosis management ......................................................................... 92 
12.3.2 
Pregnancy testing ................................................................................................. 92 
12.3.3 
Vital signs ............................................................................................................ 92 
12.3.4 
12-lead electrocardiograms .................................................................................. 92 
12.3.5 
Physical examination ........................................................................................... 93 
12.3.6 
Height and body weight ....................................................................................... 93 
12.3.7 
Assessment of suicidal ideation and behavior ..................................................... 93 
12.4 Other study measurements ............................................................................................... 93 
12.4.1 
Demographic information .................................................................................... 93 
12.4.2 
Medical History ................................................................................................... 93 
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12.4.3 
Psoriasis History .................................................................................................. 93 
12.4.4 
Data Monitoring and Adjudication Committees .................................................. 93 
13 STUDY MANAGEMENT AND ADMINISTRATION ................................................. 94 
13.1 Adherence to protocol ...................................................................................................... 94 
13.2 Monitoring ....................................................................................................................... 94 
13.2.1 
Definition of source data ..................................................................................... 94 
13.2.2 
Source data verification ....................................................................................... 95 
13.3 Data handling ................................................................................................................... 95 
13.3.1 
Case Report Form completion ............................................................................. 95 
13.3.2 
Database entry and reconciliation ............................................................... . ...... 95 
13.3.3 
Subject Screening and Enrollment log/Subject Identification Code list.............. 96 
13.4 Termination of the study ............................................................................. .................... 96 
13.5 Archiving and data retention ............................................................... ... ........................ 96 
13.6 Audit and inspection ....................................................................... . ............................. 96 
13.7 Good Clinical Practice ............................................................. . . ................................... 97 
14 STATISTICS ................................................................................................................... 97 
14.1 Definition of analysis sets .................................... . .. ..... . . ............................................ 97 
14.2 General statistical considerations .............................. ...................................................... 97 
14.3 Planned efficacy analyses ......................... .. ...... .. ......................................................... 99 
14.3.1 
Analysis of the primary efficacy variable ............................................................ 99 
14.3.1.1 
Sensitivity analyses .. .......... .................................................................... 99 
14.3.2 
Other efficacy analyses .......... . . ....................................................................... 100 
14.3.2.1 
Analysis of the secondary efficacy variables .......................................... 100 
14.3.2.2 
Analysis of the other efficacy variables .................................................. 101 
14.4 Subgroup analyses ............ ............................................................................................ 102 
14.5 Planned safety and other analyses .................................................................................. 102 
14.5.1 
Safety analyses ................................................................................................... 102 
14.5.2 
Pharmacokinetic analyses .................................................................................. 102 
14.5.3 
Immunogenicity analyses .................................................................................. 102 
14.6 Handling of protocol deviations ..................................................................................... 102 
14.7 Handling of dropouts or missing data ............................................................................ 103 
14.8 Planned interim analysis and data monitoring ............................................................... 104 
14.9 Determination of sample size ......................................................................................... 104 
15 ETHICS AND REGULATORY REQUIREMENTS .................................................... 105 
15.1 Informed consent ........................................................................................................... 105 
15.2 Subject identification cards ............................................................................................ 105 
15.3 Institutional Review Boards and Independent Ethics Committees ................................ 106 
15.4 Subject privacy ............................................................................................................... 106 
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15.5 Protocol amendments ..................................................................................................... 107 
16 FINANCE, INSURANCE, AND PUBLICATION ....................................................... 107 
17 REFERENCES .............................................................................................................. 107 
18 APPENDICES ............................................................................................................... 110 
18.1 Protocol Amendment 1 .................................................................................................. 110 
18.2 Protocol Amendment 2 .................................................................................................. 151 
19 DECLARATION AND SIGNATURE OF INVESTIGATOR ..................................... 189 
20 SPONSOR DECLARATION ........................................................................................ 190 
 
LIST OF TABLES 
Table 5‒1: 
Schedule of study assessments...................................................... . ................ 28 
Table 7‒1: 
Dosing scheme ......................................................................... ....................... 43 
Table 7‒2: 
Prohibited psoriasis medications..................................... . .............................. 46 
Table 9‒3: 
Body areas for calculation of percent BSA for PASI ..................................... 68 
Table 9‒4: 
Five-point IGA .................................................. .. ........................................... 69 
Table 9‒5: 
Scalp IGA.......................................... ......... .................................................... 70 
Table 9‒6: 
pp-IGA ....................................... .. ...... ......................................................... 71 
Table 12.1: 
Anticipated serious adverse events for the population of subjects with 
moderate to severe chronic plaque psoriasis .................................................... 76 
Table 12‒2: 
Laboratory measurements .. ... ......................................................................... 80 
Table 12‒3: 
Required investigations and follow-up for PDILI ........................................... 82 
Table 12‒4: 
PDILI laboratory measurements ...................................................................... 86 
Table 12‒5: 
PDILI information to be collected ................................................................... 87 
 
LIST OF FIGURES 
Figure 5‒1: 
Schematic diagram of PS0008 ......................................................................... 33 
Figure 12-1: 
Schematic diagram of TB test results and study eligibility ............................. 90 
Figure 14-1: 
Sequence of testing .......................................................................................... 98 
 
 
 
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LIST OF ABBREVIATIONS 
AE 
adverse event 
AESI 
adverse event of special interest 
ALP 
alkaline phosphatase 
ALT 
alanine aminotransferase 
AST 
aspartate aminotransferase 
axSpA 
axial spondyloarthritis 
AUC 
area under the curve 
BA 
Bioavailability 
BKZ Set 
Bimekizumab Set 
BMI 
body mass index 
BP 
blood pressure 
BSA 
body surface area 
cAMP 
cyclic adenosine monophosphate 
CAT 
Computed Axial Tomography 
CDC 
Centers for Disease Control 
CDMS 
clinical data management system 
CI 
confidence interval 
CMH 
Cochran-Mantel-Haenszel 
CPM 
Clinical Project Manager 
CPMP 
Committee for Proprietary Medicinal Products 
CRO 
Contract Research Organization 
CSR 
Clinical Study Report 
CTCAE 
Common Terminology Criteria for Adverse Events 
CV 
cardiovascular 
DLQI 
Dermatology Life Quality Index 
DMC 
Data Monitoring Committee 
ECG 
electrocardiogram 
eCRF 
electronic Case Report Form 
eC-SSRS 
electronic Columbia Suicide Severity Rating Scale 
EDC 
Electronic Data Capture 
ePRO 
electronic Patient-Reported Outcome 
EQ-5D-3L 
Euro-Quality of Life 5-Dimensions, 3-Levels 
ES 
Enrolled Set 
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FAS 
Full Analysis Set 
FDA 
Food and Drug Administration 
GCP 
Good Clinical Practice 
GeoMean 
geometric mean 
GMP 
Good Manufacturing Practice 
HBcAb 
anti-hepatitis B core antibody 
HBsAg 
hepatitis B surface antigen 
HCP 
healthcare practitioner 
HCV 
hepatitis C virus 
HCV Ab 
hepatitis C antibody 
HIV 
human immunodeficiency virus 
HLT 
High Level Term 
IB 
Investigator’s Brochure 
IBD 
inflammatory bowel disease 
ICF 
Informed Consent Form 
ICH 
International Council for Harmonisation 
IEC 
Independent Ethics Committee 
Ig 
immunoglobulin 
IGA 
Investigator’s Global Assessment 
IGRA 
interferon-gamma release assay  
IL 
interleukin 
IMP 
investigational medicinal product 
IRB 
Institutional Review Board 
IRT 
interactive response technology 
iv 
Intravenous 
LOCF 
last observation carried forward 
LTB 
latent tuberculosis 
LTBI 
latent tuberculosis infection 
mAb 
monoclonal antibody 
MAR 
missing at random 
MCID 
minimal clinically important difference 
MCMC 
Markov-Chain Monte Carlo 
MCS 
Mental Component Summary 
MedDRA 
Medical Dictionary for Regulatory Activities 
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MI 
multiple imputation 
MID 
minimally important difference 
mNAPSI 
Modified Nail Psoriasis Severity Index Score 
NRI 
nonresponder imputation 
NSAID 
nonsteroidal anti-inflammatory drug 
NTMB 
nontuberculous mycobacterium 
PASE 
Psoriatic Arthritis Screening and Evaluation 
PASI 
Psoriasis Area and Severity Index 
PCS 
Physical Component Summary  
PD 
pharmacodynamics  
PDE4 
phosphodiesterase 4 
PDILI 
potential drug-induced liver injury 
PEOT 
Premature End of Treatment 
PFS 
prefilled syringe 
PGADA 
Patient's Global Assessment of Disease Activity 
PHQ-9 
Patient Health Questionnaire 9 
PK 
pharmacokinetics 
PK-PPS 
Pharmacokinetics Per-Protocol Set 
pp-IGA 
palmoplantar Investigator’s Global Assessment 
PPS 
Per-Protocol Set 
PRO 
patient-reported outcome 
PS 
Patient Safety 
PsA 
psoriatic arthritis 
PSO 
Psoriasis 
Q2W 
every 2 weeks 
Q4W 
every 4 weeks 
Q8W 
every 8 weeks 
QOL 
quality of life 
RS 
Randomized Set 
SAE 
serious adverse event 
SAP 
statistical analysis plan 
sc 
subcutaneous 
scalp IGA 
scalp-specific IGA 
SD 
standard deviation 
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SF-36 
Short Form 36-Item Health Survey 
SFU 
Safety Follow-Up 
SOP 
Standard Operating Procedure 
SS 
Safety Set 
TB 
tuberculosis 
TEAE 
treatment-emergent adverse event 
TNF 
tumor necrosis factor 
ULN 
upper limit of normal 
VAS 
visual analog scale 
WBC 
white blood cell 
WPAI-SHP 
Work Productivity and Activity Impairment Questionnaire-specific health 
problem 
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1 
SUMMARY 
PS0008 is a Phase 3, multicenter, randomized, double-blind, active-comparator-controlled, 
parallel-group study to evaluate the efficacy, safety, and pharmacokinetics (PK) of bimekizumab 
(also known as UCB4940) compared with adalimumab in adult subjects with moderate to severe 
chronic plaque psoriasis (PSO). 
The study population consists of adult subjects (≥18 years of age) with a diagnosis of moderate 
to severe chronic plaque PSO (Baseline Psoriasis Area and Severity Index [PASI] ≥12 and body 
surface area [BSA] affected by PSO ≥10% and Investigator’s Global Assessment [IGA] score ≥3 
[on a 5-point scale]) who are candidates for adalimumab or for systemic PSO therapy and/or 
phototherapy. 
Approximately 600 subjects will be screened in order to have a total of 450 subjects randomized 
in the study. For each subject, the study will last a maximum of 77 weeks and will consist of 
4 periods, a Screening Period (2 to 5 weeks), a double-blind, active comparator-controlled Initial 
Treatment Period (16 weeks), a dose-blind Maintenance Treatment Period (40 weeks), and a 
Safety Follow-Up (SFU) Period (20 weeks after the final dose of the investigational medicinal 
product [IMP]). After completion of the 40-week Maintenance Treatment Period, eligible 
subjects will be allowed to enroll in an open-label study. 
Eligible subjects will be randomized 1:1:1 to receive the following blinded IMP regimens 
subcutaneously (sc): 
 Bimekizumab 320mg every 4 weeks (Q4W) administered throughout the study (150 
subjects) 
 Bimekizumab 320mg administered Q4W/every 8 weeks (Q8W) (ie, bimekizumab 320mg 
Q4W will be administered until Week 16, then bimekizumab 320mg Q8W from Week 16 
through Week 52 (150 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg every 2 weeks (Q2W) 
starting 1 week after the initial dose (ie, adalimumab will be administered according to the 
labeling recommendations) until Week 24, then bimekizumab Q4W from Week 24 to 
Week 52 (150 subjects) 
At Week 56, all subjects enrolling in the open-label study will undergo the Week 56 study 
assessments before receiving their first open-label study dose of IMP. All subjects not enrolling 
in the open-label study will have the Week 56 study assessments and will enter the 20-week 
SFU Period. 
Subjects withdrawing early from the study will undergo the Premature End of Treatment (PEOT) 
Visit assessments and will enter the 20-week SFU Period. 
The primary objective of the study is to compare the efficacy of bimekizumab administered sc 
for 16 weeks versus adalimumab in the treatment of subjects with moderate to severe chronic 
plaque PSO. The secondary objectives of the study are listed in Section 3.2. 
The co-primary efficacy variables are the PASI90 response (defined as a subject that achieves 
90% reduction from Baseline in the PASI score) at Week 16 and the IGA response (defined as 
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Clear or Almost Clear with at least a 2-category improvement relative to Baseline) at Week 16. 
The secondary efficacy variables are listed in Section 4.2.1. 
Pharmacokinetic variables are listed in Section 4.3.3, pharmacogenomic variables are listed in 
Section 4.3.4, and immunological variables are listed in Section 4.3.5. 
Pharmacokinetic, genomic, genetic, proteomic, and immunological variables will be evaluated to 
assess their relationship to treatment response. 
Safety variables to be assessed are adverse events (AEs), vital signs, electrocardiograms (ECGs), 
and measurements of laboratory parameters. 
2 
INTRODUCTION 
2.1 
Psoriasis 
Psoriasis is a common, chronic inflammatory disease characterized by a series of linked cellular 
changes in the skin: hyperplasia of epidermal keratinocytes, vascular hyperplasia and ectasia, and 
infiltration of T lymphocytes, neutrophils, and other types of leukocytes in affected skin. Though 
the pathophysiology of PSO is not fully understood, the importance of T-cells and inflammatory 
cytokines has been demonstrated by the clinical benefit provided by therapies directed at these 
targets (Krueger and Ellis, 2005). 
There are a variety of forms including plaque, guttate, inverse, pustular, and erythrodermic. 
Plaque PSO is the most common, comprising approximately 80% to 90% of all cases. 
Approximately 17% of those with PSO have moderate to severe disease (Kurd et al, 2008). 
In addition to the impact on skin, PSO has a multitude of psychosocial and emotional effects on 
patients, including increased self-consciousness, frustration, fatigue, depression, and suicidal 
ideation. As a result, patients frequently report sleeping problems, difficulties at work, problems 
interacting with family members, disrupted leisure activities, and sexual difficulties 
(Dowlatshahi et al, 2014; Gottlieb, 2005; Mukhtar et al, 2004; Ortonne, 2004; Krueger et al, 
2001). 
A number of comorbidities have been associated with PSO, especially with more severe PSO. 
Psoriatic arthritis (PsA), cardiovascular (CV) disease, metabolic syndrome, chronic pulmonary 
disease, peptic ulcer disease, renal disease, and diabetes have all been demonstrated to have an 
increased prevalence in PSO patients (Yeung et al, 2013; Christophers et al, 2010; Gisondi et al, 
2007; Gelfand et al, 2006). 
2.1.1 
Global epidemiology of psoriasis 
Psoriasis affects approximately 3% of the US adult population (Rachakonda et al, 2014; Kurd 
and Gelfand, 2009) and its onset can begin at any age (Augustin et al, 2010; Icen et al, 2009). 
The reported worldwide incidence and prevalence of PSO varies greatly depending on age, 
gender, ethnicity, and geography primarily due to genetic and environmental factors. Estimates 
of incidence and prevalence include all types of PSO. Plaque PSO is the most common form of 
the disease, therefore reported estimates of the magnitude of this condition are likely weighted 
heavily by this subtype. Both the incidence and prevalence of PSO are higher among Caucasians 
and those living in higher latitudes. Psoriasis affects approximately 2% to 4% of the population 
of western countries. Geographical differences are also influenced by case definition, study 
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design, and the definition of prevalence (Parisi et al, 2013; Langley et al, 2005; Raychaudhuri 
and Gross, 2000). 
2.1.2 
Current treatments for psoriasis 
Therapy for patients with PSO varies according to the severity of disease. Limited or mild 
disease is often treated with topical therapies such as corticosteroids and vitamin D analogs. 
Patients with more severe disease are often treated with phototherapy, methotrexate, 
cyclosporine, the oral phosphodiesterase 4 (PDE4) inhibitor apremilast, or biologic agents, such 
as tumor necrosis factor (TNF) antagonists, interleukin (IL)-12/23 inhibitors, IL-23p19 inhibitors 
and IL-17A inhibitors. The effectiveness of TNF inhibitors in the treatment of PSO has been 
demonstrated in many Phase 3 clinical studies and has led to the approval of multiple TNF 
inhibitors for use in patients with moderate to severe PSO. Interleukin inhibitors approved for 
this indication include the IL-12/23 antagonist ustekinumab, the IL-23p19 antagonist 
guselkumab, the IL-17A inhibitors secukinumab and ixekizumab, and the IL-17 receptor 
antagonist brodalumab.  
Standard therapies for PSO are listed below: 
 Topical steroids (eg, triamcinolone, mometasone, clobetasol, betamethasone, hydrocortisone) 
are generally used as first-line treatment of PSO. High-strength steroids are typically 
reserved for use on the arms and legs. Areas such as the face and skin folds (axillary, 
inguinal regions, etc) are usually treated with a low potency steroid. Chronic use of topical 
steroids can lead to corticosteroid-related side effects and is generally discouraged. 
 Vitamin D analogs (eg, calcipotriol and tacalcitol) are commonly used to treat mild to 
moderate PSO, and work best within the mild patients. They are safe but lack efficacy for 
more severe disease. 
 Phototherapy is a frequent option for moderate to severe patients, but the inconvenience of 
multiple treatment visits and varying efficacy limits its use in the market. 
 Methotrexate is a systemic immunosuppressant and is used in moderate to severe PSO 
patients. Toxicity concerns, particularly in older patients, are a major drawback. 
 Cyclosporine is a systemic immunosuppressant used in patients with severe, recalcitrant, 
PSO who have failed at least one systemic therapy or in whom other systemic therapies are 
contraindicated. In recommended dosages cyclosporine can cause systemic hypertension and 
nephrotoxicity, therefore, renal function must be monitored during therapy. 
 Apremilast is an oral small-molecule inhibitor of PDE4 that is also approved for treatment of 
adults with moderate to severe plaque PSO. Phosphodiesterase 4 inhibitors work 
intracellularly to modulate a network of proinflammatory and anti-inflammatory mediators. 
Phosphodiesterase 4 is a cyclic adenosine monophosphate (cAMP)-specific PDE and the 
dominant PDE in inflammatory cells. Phosphodiesterase 4 inhibition elevates intracellular 
cAMP levels, which in turn down-regulates the inflammatory response by modulating the 
expression of TNFα, IL-23, IL-17, and other inflammatory cytokines. 
 Biologics, including TNFα inhibitors (adalimumab, etanercept, and infliximab), 
IL-12/23 inhibitors (ustekinumab), the IL-23p19 antagonist (guselkumab), the IL-17A 
inhibitors (secukinumab and ixekizumab), and the IL-17 receptor antagonist brodalumab are 
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the treatment options of choice for patients with moderate to severe plaque PSO who are 
candidates for systemic therapy or phototherapy. These products are injected sc or delivered 
via intravenous (iv) infusion. Different from the traditional systemic drugs that impact the 
entire immune system, biologics target specific parts of the immune system and offer reduced 
multi-organ toxicity and adverse effects associated with traditional treatments. 
 TNFα inhibitors, while effective, come with boxed warnings including the risk of serious 
infections and reports of lymphoma and malignancy in children and adolescent patients. 
The efficacy of TNFα inhibitors in treating PSO is attributed to their inhibition of 
Th17-T cells.  
 Ustekinumab has been approved in the US and the EU for the treatment of patients with 
moderate to severe plaque PSO who are candidates for phototherapy or systemic therapy. 
Ustekinumab is a human immunoglobulin (Ig) G1κ monoclonal antibody that binds with 
specificity to the p40 protein subunit used by both the IL-12 and IL-23 cytokines, 
naturally occurring cytokines that are involved in inflammatory and immune responses, 
such as natural killer cell activation and CD4+ T-cell differentiation and activation.  
 Secukinumab and ixekizumab have been approved in the US and the EU for the treatment 
of moderate to severe plaque PSO in adult patients who are candidates for systemic 
therapy or phototherapy. Secukinumab is a human IgG1 monoclonal antibody that 
selectively binds to the interleukin-17A (IL-17A) cytokine and inhibits its interaction 
with the IL-17 receptor. Ixekizumab is a humanized IgG4 monoclonal antibody that 
selectively binds with the interleukin 17A (IL-17A) cytokine and inhibits its interaction 
with the IL-17 receptor. IL-17A is a naturally occurring cytokine that is involved in 
normal inflammatory and immune responses. Both drugs inhibit the release of 
proinflammatory cytokines and chemokines. 
 Guselkumab has been approved in the US and the EU for the treatment of adult patients 
with moderate to severe plaque PSO who are candidates for systemic therapy or 
phototherapy. It is a human monoclonal IgG1λ antibody that selectively binds to the p19 
subunit of interleukin 23 (IL-23) and inhibits its interaction with the IL-23 receptor. 
IL-23 is a naturally occurring cytokine that is involved in normal inflammatory and 
immune responses. Guselkumab inhibits the release of proinflammatory cytokines and 
chemokines. 
 Brodalumab has been approved in the US for the treatment of moderate to severe plaque 
psoriasis in adult patients who are candidates for systemic therapy or phototherapy and 
have failed to respond or have lost response to other systemic therapies. In the EU, 
brodalumab is indicated for the treatment of moderate to severe plaque PSO in adult 
patients who are candidates for systemic therapy. Brodalumab is a human monoclonal 
IgG2 antibody that selectively binds to human IL-17RA and inhibits its interactions with 
cytokines IL-17A, IL-17F, IL-17C, IL-17A/F heterodimer and IL-25. Blocking IL 17RA 
inhibits IL-17 cytokine-induced responses including the release of proinflammatory 
cytokines and chemokines. Brodalumab has a black box warning regarding suicidal 
ideation and behavior. 
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2.2 
Bimekizumab 
Bimekizumab (UCB4940) is an engineered, humanized full-length monoclonal antibody (mAb) 
of immunoglobulin (Ig) G1 subclass of approximately 150,000 Daltons which is expressed in a 
genetically engineered Chinese hamster ovary cell line. Bimekizumab has high affinity for 
human IL-17A and human IL-17F and selectively and potently inhibits the activity of both 
isoforms in vitro. Interleukin-17A and IL-17F are key proinflammatory cytokines believed to 
play important roles in autoimmune and inflammatory diseases. Bimekizumab is being 
developed for the treatment of patients with inflammatory diseases such as PsA, PSO, and axial 
spondyloarthritis (axSpA). 
While anti-IL-17A antibodies have demonstrated efficacy in patients with PSO, PsA, and 
ankylosing spondylitis, as yet, no therapeutic approach selectively and potently inhibits the 
activity of both IL-17A and IL-17F isoforms in vitro. Bimekizumab is an engineered, 
humanized, full-length IgG1 mAb which has been designed to inhibit the activity of IL-17A and 
IL-17F subtypes of IL-17. This property makes bimekizumab distinct from the other IL-17-
targeting agents like secukinumab and ixekizumab (selective anti-IL-17-A mAb), or brodalumab 
(anti-IL-17 receptor mAb). 
Overexpression of IL-17A, IL-17C, and IL-17F in lesion tissue suggests that broader IL-17 
blockade may be more beneficial in the treatment of plaque PSO. However, blocking all IL-17 
isoforms (including the IL-17E isoform, also known as IL-25) may not be the optimal approach. 
The role of IL-25 in PSO and other IL-17 mediated diseases has not been well established, 
however it has been suggested that IL-25 may play a beneficial role in inflammatory conditions 
associated with type 1 T helper (Th-1) mediated immune responses, such as PSO (as opposed to 
type 2 T helper [Th-2) mediated) (Valizadeh et al, 2015). Thus, it can be hypothesized that 
inhibition of both IL-17A and IL-17F is associated with additional benefits in PSO compared to 
the selective IL-17A inhibition or a broader IL-17 blockade. 
2.2.1 
Clinical 
2.2.1.1 
Completed studies 
Five clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with mild to 
moderate plaque PSO, RA0124 in 30 healthy volunteers, PA0007 in 53 subjects with PsA, 
UP0031 in 12 healthy volunteers, and UP0042 in 48 healthy volunteers.  
UP0008 was a Phase 1, single ascending dose study in adults with mild to moderate PSO 
affecting ≤5% BSA. In this blinded study, single doses of up to 640mg (approximately 8mg/kg 
in an 80kg adult) were evaluated without any safety concerns. A total of 26 subjects with PSO 
with less than 5% of body surface involvement were treated with a range of single iv doses from 
8 to 640mg. There were no clinically relevant safety findings identified at any dose and all doses 
were well tolerated. The pre-specified exploratory assessment of disease activity showed 
clinically relevant and statistically significant improvements at the higher doses studied. 
RA0124 was a Phase 1, open-label, parallel-group, single-dose study in healthy subjects. The 
primary objective of this study was to determine the absolute bioavailability (BA) of single sc 
doses of bimekizumab (80mg and 160mg). The secondary objectives were to evaluate the dose 
proportionality of bimekizumab 80mg and 160mg sc, and to evaluate the safety and tolerability 
of these sc doses and 160mg given by iv infusion. In RA0124, the absolute BA was similar for 
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the 2 doses tested (0.656 and 0.631 for the bimekizumab 80mg and 160mg sc doses, 
respectively). The PK of bimekizumab was linear in the tested dose range and the median t1/2 
following sc administration was similar to that following iv administration (27.81 days and 
28.25 days for bimekizumab 160mg sc and 160mg iv, respectively). 
Bimekizumab has also been investigated in a Phase 1b, proof of concept, randomized, placebo 
controlled, multiple dose study (PA0007). The primary objective of PA0007 was to assess the 
safety and PK of multiple dose administration of iv bimekizumab in subjects with PsA. Four 
active doses and a placebo were tested. Drug was administered as a loading dose at Week 0, and 
2 additional doses were administered at Week 3 and Week 6. In each treatment group, subjects 
received a total of 3 doses of bimekizumab, administered every 3 weeks as shown below: 
 80mg loading dose followed by 40mg at Weeks 3 and 6 
 160mg loading dose followed by 80mg at Weeks 3 and 6 
 240mg loading dose followed by 160mg at Weeks 3 and 6 
 560mg loading dose followed by 320mg at Weeks 3 and 6 
The results of this study demonstrated that all doses of bimekizumab were well tolerated and 
there were no unexpected clinically relevant safety findings. 
Infections (mostly nasopharyngitis) were the most commonly reported events in both the active 
treatment and the placebo group. None of the infections were considered serious or required 
treatment with antibiotics. Two subjects in the active treatment group experienced 1 local 
candida infection each (oropharhyngitis and vulvovaginitis, respectively) that were non-serious 
and resolved with topical therapy. There was a potential reduction in mean neutrophil count in 
the active treatment group, although this drop was not clinically relevant and a clear relationship 
with dose or time was not evident. Some increases in liver function tests were reported, but none 
had a convincing relationship to exposure to IMP. The exploratory analysis showed clinically 
relevant improvement in activity of PsA and in skin involvement in those subjects with 
concomitant active psoriatic lesions. 
UP0031 was a Phase 1, open-label, parallel-group, randomized, single-dose study to evaluate the 
BA, PK, and tolerability of 2 different formulations of bimekizumab in healthy subjects. Subjects 
receiving Formulation A (histidine-based) were administered two 1mL injections of 80mg each 
of bimekizumab and subjects receiving Formulation B 
) were administered a 
single injection of bimekizumab 160mg given as a 1mL injection. Six subjects were randomized 
to each bimekizumab formulation. The geometric means (GeoMeans) for area under the curve 
(AUC) were similar between bimekizumab 2x80mg and 1x160mg groups and the relative BA for 
Formulation B vs Formulation A was 96.1% (95% confidence interval [CI]: 72.7%, 127.0%). 
Administration of the 2 formulations of bimekizumab used in this study identified no new safety 
issues. There were no treatment-emergent adverse events (TEAEs) leading to discontinuation, 
and no serious adverse events (SAEs) or fatalities were reported. The only preferred term 
experienced by more than 1 subject in either treatment group was injection site pain (5 subjects 
[83.3%] and 3 subjects [50.0%] in the 2x80mg and 1x160mg groups, respectively). The most 
frequently reported TEAE considered related to the IMP was injection site pain, experienced by 
5 subjects [83.3%] and 3 subjects [50.0%] in the 2x80mg and 1x160mg groups, respectively. 
There were no clinically significant laboratory values reported in the study. 
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UP0042 was a randomized double-blind, placebo-controlled, single-dose, parallel-group study to 
evaluate the safety, tolerability, and PK of bimekizumab administered as an sc injection to 
Japanese and Caucasian healthy subjects. This study demonstrated that the PK profiles following 
single administration of 80mg, 160mg, and 320mg with an sc injection were dose proportional 
with a linear elimination in both Japanese and Caucasian subjects and that the PK profiles of 
Japanese and Caucasian subjects were considered to be generally similar. A single dose of 
bimekizumab (80mg, 160mg, or 320mg) administered as an sc injection was generally safe and 
well tolerated in healthy Japanese and Caucasian subjects and no major differences in safety 
findings were observed between Japanese and Caucasian subjects. 
2.2.1.2 
Ongoing studies 
Four additional studies of bimekizumab in the treatment of PSO are ongoing.  
 PS0010 is a Phase 2b, double-blind, placebo-controlled, dose ranging study to evaluate the 
safety, efficacy, PK, and pharmacodynamics (PD) of bimekizumab in adult subjects with 
moderate to severe chronic plaque PSO. 
 PS0011 is a long-term extension study for subjects who completed PS0010 to assess the 
long-term safety, tolerability, and efficacy of bimekizumab. 
 PS0016 is a Phase 2a, subject-blind, Investigator-blind study to evaluate the time course of 
PD response, safety, and PK of bimekizumab in adult subjects with moderate to severe 
chronic plaque PSO. 
 PS0018 is a long-term extension study for eligible subjects from PS0016 to assess the safety, 
tolerability, and efficacy of bimekizumab. 
Bimekizumab is also being evaluated in the treatment of other indications (eg, PsA, axSpA, 
hidradenitis suppurativa). Additional information on the clinical data for bimekizumab is 
available in the current version of the Investigator’s Brochure (IB). 
2.2.2 
Nonclinical 
Parallel inhibition of IL-17A and IL-17F has been shown to be efficacious in a variety of animal 
models of inflammatory disease. Intravenously administered bimekizumab was well tolerated in 
repeat dose toxicology studies in Cynomolgus monkeys with a no adverse effect level of 
200mg/kg/week. The findings of note in toxicity studies were diarrhea related to infectious 
enteritis (observed in the single dose study) and asymptomatic mild colonic ulceration in a 
proportion of animals (in the repeat dose study); this latter finding was not associated with 
hematology abnormalities. Data suggest that bimekizumab has induced primary lesions to the 
mucosa associated lymphoid tissue via a pharmacologically-related mechanism. In a second 
repeat-dose study, none of the minor apoptosis/necrosis findings observed in gut associated 
lymph nodes were revealed. In animals given the highest dose of bimekizumab in the study 
(20mg/kg/week), a slightly higher number of protozoa (Balantidium coli) was observed in the 
cecum and colon as compared to the control animals and low dose animals. Therefore, gut 
associated lymph node lesions observed in the first study are considered to be accidental and/or 
linked to exaggerated pharmacology and proliferation of Balantidium coli and is considered the 
consequence of a change in local mucosal immunity. To date, similar findings have not been 
seen in studies in humans. 
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Additional information on the nonclinical data for bimekizumab is available in the current 
version of the IB. 
3 
STUDY OBJECTIVE(S) 
3.1 
Primary objective 
The primary objective of the study is to compare the efficacy of bimekizumab administered sc 
for 16 weeks versus adalimumab in the treatment of subjects with moderate to severe chronic 
plaque PSO. 
3.2 
Secondary objectives 
The secondary objectives of the study are to: 
 Evaluate the efficacy of bimekizumab compared to adalimumab after 4, 16, and 24 weeks of 
treatment 
 Evaluate the efficacy of bimekizumab compared to adalimumab at achieving complete 
clearance (PASI100) after 16 weeks and 24 weeks of treatment 
 Assess the maintenance of efficacy of bimekizumab dosing Q4W versus Q8W at Week 56 
 Assess TEAEs, SAEs, and TEAEs leading to withdrawal adjusted by duration of subject 
exposure to study treatment 
3.3 
Other objectives 
The other objectives of the study are to demonstrate the effects of bimekizumab on aspects of the 
disease: 
 Assess the maintenance of efficacy of bimekizumab dosing Q4W versus Q8W during the 
Maintenance Treatment Period 
 Assess the efficacy of bimekizumab over time 
 Assess the change of skin-related quality of life (QOL) 
 Assess the change of general health-related QOL 
 Assess the change in nail PSO over time in subjects with nail PSO at Baseline 
 Assess the change in scalp PSO over time in subjects with scalp PSO at Baseline 
 Assess the change in palmoplantar PSO over time in subjects with palmoplantar PSO at 
Baseline 
 Assess the symptoms of PsA as measured by the Psoriatic Arthritis Screening and Evaluation 
(PASE) questionnaire 
 Assess the change of patient-reported joint symptoms in subjects with PsA at Baseline 
 Assess the change in symptoms of PSO as reported by subjects using the Patient Symptom 
Diary (all items) through Week 24 
 Assess depression 
 Assess the PK of bimekizumab 
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 Assess the immunogenicity of bimekizumab 
 Assess work productivity  
 Assess the effect of bimekizumab on gene and protein expression, and explore the 
relationship between genomic, genetic, and proteomic biomarkers and disease biology, drug 
treatment and inflammatory and immune responses (from consenting subjects who agree to 
participate in the biomarker substudy) 
 Assess the safety and tolerability of bimekizumab 
4 
STUDY VARIABLES 
4.1 
Primary efficacy variable 
The co-primary efficacy variables are the PASI90 response (defined as a subject that achieves 
90% reduction from Baseline in the PASI score) at Week 16 and the IGA response (defined as 
Clear or Almost Clear with at least a 2-category improvement relative to Baseline) at Week 16. 
4.2 
Secondary variables 
4.2.1 
Secondary efficacy variables 
The secondary efficacy variables are: 
 PASI90 response at Week 24  
 IGA response (Clear or Almost Clear with at least 2-category improvement relative to 
Baseline) at Week 24  
 PASI75 response at Week 4 
 PASI100 response at Week 16 and 24 
 PASI90 response at Week 56 
 IGA response at Week 56 
4.2.2 
Secondary safety variables 
 TEAEs adjusted by duration of subject exposure to study treatment 
 SAEs adjusted by duration of subject exposure to study treatment 
 TEAEs leading to withdrawal adjusted by duration of subject exposure to study treatment 
4.3 
Other variables 
The other variables are listed below and will be evaluated according to the planned assessments 
Table 5‒1. 
4.3.1 
Other efficacy variables 
The other efficacy variables are listed below and will be evaluated according to the planned 
assessments Table 5‒1. This excludes the time points for the primary and secondary variables 
specified above in Section 4.1 and Section 4.2.1, respectively. 
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Change from Baseline variables evaluated are relative to the Baseline (first dose) Visit. In 
addition, for subjects who start with adalimumab and switch treatment at the Week 24 Visit, 
change from Baseline variables during the Maintenance Treatment Period may be evaluated 
relative to both the Baseline (first dose) Visit and the Week 24 Visit. For simplicity, “change 
from Baseline” is used below for all such variables. Greater detail on the definition of Baseline 
for different summaries will be provided in the Statistical Analysis Plan (SAP). Unless otherwise 
stated PASI responder rates will be calculated relative to the Baseline Visit (first dose). 
The other efficacy variables are: 
 PASI50, PASI75, PASI90, and PASI100 response 
 Time to PASI50, PASI75, PASI90, and PASI100 response during the Initial Treatment 
Period 
 Absolute and percent change from Baseline in PASI score 
 IGA response (Clear) 
 IGA response (Clear or Almost Clear with at least 2-category improvement relative to 
Baseline) 
 Shift from Baseline in IGA score 
 Absolute and percent change from Baseline in the BSA affected by PSO 
 Absolute and percent change from Baseline in the product of IGA and BSA (IGAxBSA) 
 Change from Baseline in the Dermatology Life Quality Index (DLQI) 
 Percent of subjects achieving a DLQI total score of 0 or 1 
 Percentage of subjects achieving a minimal clinically important difference (MCID) 
(improvement from Baseline of 4 or more) in the DLQI 
 Change from Baseline in Patient’s Global Assessment of Disease Activity (PGADA) for the 
arthritis visual analog scale (VAS) in subjects with PsA as defined by PASE score at 
Baseline 
 Change from Baseline in Patient Global Assessment of PSO score 
 Change from Baseline in the Patient Symptom Diary responses 
 Scalp-specific Investigator’s Global Assessment (scalp IGA) response (Clear or Almost 
Clear) for subjects with scalp PSO at Baseline 
 Change from Baseline in modified Nail Psoriasis Severity Index (mNAPSI) score for 
subjects with nail PSO at Baseline 
 Palmoplantar Investigator’s Global Assessment (pp-IGA) response (Clear or Almost Clear) 
for subjects with palmoplantar PSO at Baseline 
 Change from Baseline in the PASE questionnaire scores (function score, symptom score, and 
total score) 
 Shift from Baseline in PASE score suggestive of PsA (<47 versus ≥47) 
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 Change from Baseline in Short Form 36-item Health Survey (SF-36) Physical Component 
Summary (PCS) score, and Mental Component Summary (MCS) score, and individual 
domains 
 Responses to Euro-Quality of Life 5-Dimensions, 3 levels (EQ-5D-3L), absolute and changes 
from Baseline in EQ-5D-3L VAS scores 
 Change from baseline in Patient Health Questionnaire-9 (PHQ-9) scores 
 Change from Baseline in Work Productivity and Activity Impairment Questionnaire-specific 
health problem (WPAI-SHP) V2.0 adapted to PSO scores 
4.3.2 
Other safety variables 
Safety variables to be assessed are: 
 Severity and frequency of AEs 
 Change from Baseline in vital signs 
 ECG results 
 Change from Baseline in clinical laboratory values (chemistry, hematology, and urinalysis) 
Physical examination findings considered clinically significant changes since the physical 
examination at the Screening Visit will be recorded as AEs  
4.3.3 
Pharmacokinetic variable 
The PK variable is the plasma concentration of bimekizumab. 
4.3.4 
Pharmacogenomic variables 
Additional blood samples will be collected from subjects who consent to participate in the 
substudy at specific time points and stored at -80°C for up to 20 years. 
Genomic, genetic, epigenetic, proteins, and metabolite biomarkers may be measured to evaluate 
the relationship with response to treatment with bimekizumab, PSO disease biology, and 
inflammatory and immune response processes. The nature and format of these tentative substudy 
analyses will be determined when the results of the main study are made available. 
The candidate exploratory variables are the blood or blood derivative (eg, serum) concentrations 
of cytokines and chemokines of relevance to IL-17A/F signaling pathway and PSO biology. 
Additional variables may include but will not be limited to serum complement concentrations. 
4.3.5 
Immunological variable 
The immunological variable is the anti-bimekizumab antibody level prior to and following IMP. 
5 
STUDY DESIGN 
5.1 
Study description 
PS0008 is a Phase 3, multicenter study consisting of a 16-week, randomized, double-blind, 
parallel-group, active-comparator-controlled Initial Treatment Period followed by a 40-week, 
Maintenance Treatment Period to evaluate the efficacy and safety of bimekizumab in adult 
subjects with moderate to severe chronic plaque PSO. To be eligible to participate in this study, 
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subjects must be adults with a diagnosis of moderate to severe PSO (Baseline PASI ≥12 and 
BSA affected by PSO ≥10% and IGA score ≥3 [on a 5-point scale]) who are candidates for 
systemic PSO therapy and/or phototherapy. Adalimumab will be administered per the local label. 
Up to 30% of subjects may have been previously exposed to a biologic therapy (see Exclusion 
Criterion #23, Section 6.2). 
5.2 
Study periods 
This study will include 4 periods, a Screening Period (2 to 5 weeks), an Initial Treatment Period 
(16 weeks), a Maintenance Treatment Period (40 weeks), and a SFU Period (20 weeks after the 
final dose of IMP). After completion of the Maintenance Treatment Period, eligible subjects will 
be allowed to enroll in an open-label study. Subjects enrolling into the open-label study will not 
have the PS0008 SFU Visit. 
5.2.1 
Screening Period 
The Screening Period will last 2 weeks, but can be extended up to a total of 5 weeks in cases 
where a laboratory assessment needs to be repeated or to allow washout of prohibited 
medications. During this time, eligible subjects will be informed about the study and sign the 
Informed Consent Form (ICF), laboratory data (hematology, urine, and biochemistry tests) will 
be obtained, and the doses of medications used to treat PsA, will be verified as stable. The 
Screening Period will also enable washout of any medications not permitted for use during the 
study. Subjects who require prophylaxis for latent tuberculosis (LTB) infection must be on 
treatment for at least 8 weeks prior to their first dose of IMP. These subjects may be rescreened 
once they have completed the first 8 weeks of prophylaxis treatment. 
One rescreening may be allowed after consultation with the Medical Monitor. 
The assessments to be performed at the Screening Visit are presented in Table 5‒1. 
5.2.2 
Double-blind Initial Treatment Period 
During the active-controlled 16-week Initial Treatment Period, approximately 450 subjects will 
be randomized 1:1:1 to receive the following blinded IMP regimens: 
 Bimekizumab 320mg administered Q4W throughout the study (150 subjects) 
 Bimekizumab 320mg administered Q4W until Week 16 (150 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg Q2W starting 1 week 
after the initial dose (ie, adalimumab will be administered according to the labeling 
recommendations) until Week 24 (150 subjects) 
Investigational medicinal products will be administered in the clinic by sc injection at the time 
points specified in the schedule of study assessments (Table 5‒1). 
Subjects will be followed in a double-blind fashion. Subjects may receive placebo injections at 
certain visits in order to blind the IMP. The assessments to be performed at each Initial 
Treatment Period Visit are presented in Table 5‒1. 
The active comparator-controlled Initial Treatment Period will be used to demonstrate the 
efficacy of bimekizumab versus adalimumab. Efficacy of bimekizumab versus adalimumab will 
be measured at Week 16 because it was the time point for the primary endpoint in prior pivotal 
studies of adalimumab in PSO where efficacy was demonstrated. 
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Subjects withdrawing early from the study will undergo the PEOT Visit assessments and will 
enter the SFU Period. Subjects withdrawing early from the study will not be eligible for 
inclusion in the open-label study. 
5.2.3 
Dose-blind Maintenance Treatment Period 
After the 16-week Initial Treatment Period, subjects will enter the 40-week Maintenance 
Treatment Period. Treatment during the Maintenance Treatment Period will start at Week 16 and 
subjects will return to the clinic Q4W or Q8W through Week 56. The IMP will be administered 
in the clinic by sc injection at the time points specified in the schedule of study assessments 
(Table 5‒1). Treatment during the Maintenance Treatment Period will be based on initial 
treatment per the following: 
 Subjects in the bimekizumab 320mg Q4W treatment arm will continue to receive 
bimekizumab 320mg Q4W. 
 Subjects in the bimekizumab 320mg Q4W/Q8W treatment arm will receive bimekizumab 
Q8W from Week 16 through Week 52. 
 Subjects in the adalimumab treatment arm will receive bimekizumab 320mg Q4W from 
Week 24 to Week 52. 
Subjects may receive placebo injections at certain visits in order to blind the IMP (see 
Section 7.2). 
At the end of the Maintenance Treatment Period, all subjects enrolling in the open-label study 
will, after signing a new ICF, undergo the Week 56 study assessments and then receive their first 
dose of bimekizumab in the open-label study  All subjects not enrolling in the open-label study 
will have the Week 56 study assessments and will enter the SFU Period. 
The assessments to be performed at each visit of the Maintenance Treatment Period are 
presented in Table 5‒1. 
5.2.4 
Safety Follow-Up Period 
All subjects not continuing in the open-label study, including those withdrawn from IMP, will 
have a SFU Visit 20 weeks after their final dose of IMP. 
The assessments for the SFU Visit are presented in in Table 5‒1. 
5.2.5 
Premature End of Treatment 
Subjects withdrawing early from the study will undergo the PEOT Visit assessments (see 
Section 8.4) and will enter the SFU Period. 
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5.3 
Study duration per subject 
For each subject, the study will last a maximum of up to 77 weeks, as follows: 
 Screening Period: 2 to 5 weeks 
 Double-blind, active-controlled Initial Treatment Period: 16 weeks 
 Maintenance Treatment Period: 40 weeks 
 Safety Follow-Up Period: a SFU Visit is planned 20 weeks after the final dose of IMP (for 
subjects not enrolling in the open-label study) 
After the 40-week Maintenance Treatment Period, subjects will be allowed to enroll in an open-
label study, in which case subjects will undergo the Week 56 study assessments before receiving 
their first open-label IMP dose. The SFU Visit will not be required for subjects who enroll in the 
open-label study. 
The end of the study is defined as the date of the last visit of the last subject in the study. 
5.4 
Planned number of subjects and site(s) 
Approximately 600 subjects will be screened in order to have 450 subjects randomized in the 
study. There will be approximately 150 subjects per treatment arm. The planned number of study 
sites is approximately 100. Every eligible subject who signs an ICF will be expected to be 
randomized. 
5.5 
Anticipated regions and countries 
The regions planned for study conduct are North America, Western Europe, Central/Eastern 
Europe, and Asia/Australia, with possible extension to other regions and countries. 
5.6 
Schedule of study assessments 
The schedule of study assessments for all subjects enrolled in the study is presented in 
Table 5‒1. At each visit, all study assessments should be performed prior to administration of 
IMP. 
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Table 5‒1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol 
activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Informed consentc 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Xd  
 
Inclusion/exclusion 
X X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
Demographic data 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Psoriasis history 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Significant past 
medical history and 
concomitant 
diseases 
X Xe 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical 
examinationf,g 
X X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Vital signsh 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and 
biochemistry 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
 
X 
 
X 
 
X 
X 
Urinalysis 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
ECG 
X  
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Pregnancy testingi 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
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Table 5‒1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol 
activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Hepatitis B and C 
testingj 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV testingk 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest x-rayl 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IGRA Tuberculosis 
test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
Tuberculosis 
questionnaire 
X X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
bimekizumab 
plasma 
concentrationsm 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
anti-bimekizumab 
antibodiesm 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample 
genomic, 
proteomic, and 
metabolomics, and 
candidate 
biomarker 
analysesc,m 
 
X 
X 
 
 
 
X 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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Table 5‒1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol 
activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Blood sample 
genetic/epigenetic 
analysesc,m 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PASI  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Percentage of BSA 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PHQ-9 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
eC-SSRS 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Patient Symptom 
Diary (daily)  
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
scalp IGA 
 
X 
Xn 
Xn 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn  
Xn  
Xn  
Xn  
Xn 
 
mNAPSI 
 
X 
 
 
Xo 
 
Xo 
 
Xo 
 
Xo 
 
 Xo 
 
Xo  
Xo  
Xo  
Xo  
Xo 
 
pp-IGA 
 
X 
 
 
Xp 
 
Xp 
 
Xp 
 
Xp 
 
 Xp 
 
Xp  
Xp  
Xp  
Xp  
Xp 
 
EQ-5D-3L 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
SF-36 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Patient global 
assessment of 
psoriasisq 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
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Table 5‒1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol 
activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
PASE  
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PGADAr 
 
X 
 
 
X 
 
 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
WPAI-SHP V2.0 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Concomitant 
medication 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Bimekizumab, 
adalimumab, or 
placebo 
administrations 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
BSA=Body Surface Area; CV=cardiovascular; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case Report Form; eC-SSRS=electronic 
Columbia Suicide Severity Rating Scale; EQ-5D-3L=Euro-Quality of Life 5-Dimensions 3 Levels; GI=gastrointestinal; HCV=hepatitis C virus; HIV=human immunodeficiency 
virus; ICF=Informed Consent Form; IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; IMP=investigational medicinal product; IRT=interactive 
response technology; mNAPSI=Modified Nail Psoriasis Severity Index Score; PASE=Psoriatic Arthritis Screening and Evaluation; PASI=psoriasis area severity index; 
PEOT=Premature End of Treatment Visit; PGADA=Patient Global Assessment of Disease Activity; PHQ-9=Patient Health Questionnaire-9; pp-IGA=palmoplantar Investigator’s 
Global Assessment; PsA=psoriatic arthritis; SF-36=Short Form 36-item Health Survey; SFU=Safety Follow-Up; scalp IGA=scalp-specific Investigator’s Global Assessment; 
TB=tuberculosis; WPAI-SHP=Work Productivity and Activity Impairment Questionnaire-specific health problem 
a Visit windows of ±3 days from the first dose to the Week 24 visit. Visit windows of ±7 days from the Week 28 visit to the Week 52 visit. The SFU Visit 
window is ±7 days from final dose. 
b The SFU Visit will occur 20 weeks after the final dose for subjects who do not enroll in the open-label study. 
c All genomic, proteomic, and metabolomics samples will be stored at -80°C at the central biorepository for up to 20 years. 
d A separate ICF is required to be completed for the open-label study. 
e Ensure no significant changes in medical history. 
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Table 5‒1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol 
activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
f Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
g The physical examination will be performed as per Section 12.3.5 . 
h Vital signs (sitting systolic and diastolic blood pressure, pulse rate, and body temperature) are to be measured prior to blood sampling, and prior to dosing, 
where applicable. 
i Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
j Subjects who have evidence of or test positive for hepatitis B by any of the following criteria: 1) positive for hepatitis B surface antigen (HBsAg+); 2) positive 
for anti-hepatitis B core antibody (HBcAb+) are excluded. A positive test for HCV is defined as: 1) positive for hepatitis C antibody (anti-HCV Ab), and 
2) positive via a confirmatory test for HCV (for example, HCV polymerase chain reaction) are also excluded. Subjects will also be tested for anti-hepatitis B 
surface antibody. 
k The HIV test results will not be recorded in the eCRF. 
l Screening chest x-ray must occur within 3 months prior to Screening Visit. 
m All blood samples taken prior to dosing. 
n The scalp IGA will only be assessed for those subjects with scalp involvement (scalp IGA score >0) at Baseline. 
o The mNAPSI will be assessed only in subjects with nail involvement (mNAPSI score >0) at Baseline. 
p The pp-IGA will only be assessed in subjects with palmoplantar involvement (pp-IGA score >0) at Baseline. 
q The Patient Global Assessment of psoriasis will be performed as part of the patient symptoms diary on a weekly basis from Screening through the Initial 
Treatment Period at the specified clinic visits. During the Maintenance Treatment Period this assessment will be completed at the specified clinic visits. 
r The PGADA is assessed for all subjects at Baseline  At all subsequent visits, the PGADA is only for subjects with PsA at Baseline (defined as a past medical 
history of PsA or PASE ≥47). 
s IMP administration is based on randomization. The dosing window is ±3 days relative to the scheduled dosing visit through Week 24. The dosing window is ±7 
days from Week 28 through the end of the study. 
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5.8 
Rationale for study design and selection of dose 
5.8.1 
Study design 
A randomized, active-controlled study design has been selected to demonstrate efficacy and 
safety of bimekizumab for regulatory approval. The study population will include adults with 
moderate to severe chronic plaque PSO and allow subjects who have received previous biologic 
treatment as well as those who are biologic treatment naïve. The primary efficacy outcome 
measures (based on PASI and IGA) and other efficacy assessments included in this study are 
consistent with those used for other PSO studies and are considered appropriate for establishing 
efficacy of bimekizumab. An Initial Treatment Period of 16 weeks will be used to demonstrate 
the efficacy of bimekizumab compared with adalimumab. The study duration extends beyond the 
Initial Treatment Period (to 56 weeks) to allow for collection of long-term safety and efficacy 
data. 
At Week 24, subjects on adalimumab treatment are re-allocated to treatment with bimekizumab 
320mg Q4W. This allows for a controlled evaluation of the safety and efficacy of switching from 
a product with one mechanism of action to another, which is known to occur in clinical practice 
due to either loss of response or access. In a recent PSO study in which subjects were switched 
from adalimumab to a treatment with a different mechanism of action, there was no evidence of 
an increased safety risk following the switch without washout (Reich et al, 2017). 
5.8.2 
Dose selection 
Bimekizumab doses ranging from 64mg to 480mg were evaluated in the Phase 2b multicenter, 
randomized, double-blind, placebo-controlled, parallel-group, dose-ranging study PS0010. 
Bimekizumab 320mg was found to have an acceptable safety profile, only required 2 injections 
per treatment administration, and achieved significant PASI responses at Week 12 (summarized 
in the IB). Furthermore, data from the Phase 2a multicenter, randomized, subject-blind, 
Investigator-blind study PS0016 and PK/PD modeling in this PSO population indicates improved 
responses through Week 16. Therefore, a bimekizumab dose of 320mg (Q4W initial and Q4W or 
Q8W maintenance) was selected for this study. 
6 
SELECTION AND WITHDRAWAL OF SUBJECTS 
6.1 
Inclusion criteria 
To be eligible to participate in this study, all of the following criteria must be met at Screening 
and at the Baseline Visit: 
1. Subject has provided informed consent.  
2. Subject is considered reliable and capable of adhering to the protocol (eg, able to understand 
and complete diaries), visit schedule, or medication intake according to the judgment of the 
Investigator. 
3. Male or female at least 18 years of age. 
4. Chronic plaque PSO for at least 6 months prior to the Screening Visit. 
5. PASI ≥12 and BSA affected by PSO ≥10% and IGA score ≥3 on a 5-point scale. 
6a. Subject is a candidate for systemic PSO therapy and/or phototherapy. 
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7. Subject must be considered, in the opinion of the Investigator, to be a suitable candidate for 
treatment with adalimumab per regional labeling and has no contraindications to receive 
adalimumab as per the local label. 
8. Female subjects must be: 
 Postmenopausal. Menopause is defined as 12 consecutive months of amenorrhea, for 
which there is no other obvious pathological or physiological cause. 
 Permanently sterilized (eg, tubal occlusion, hysterectomy, bilateral salpingectomy). 
 Or, if of childbearing potential (and engaged in sexual activity that could result in 
procreation), must be willing to use a highly effective method of contraception 
throughout the duration of the study until 20 weeks after last administration of IMP, and 
have a negative pregnancy test at Visit 1 (Screening) and immediately prior to first dose. 
The following methods are considered highly effective when used consistently and 
correctly: 
o Combined (estrogen and progestogen) hormonal contraception associated with 
inhibition of ovulation (oral, intravaginal, or transdermal)  
o Progestogen-only hormonal contraception associated with inhibition of ovulation 
(oral, injectable, implantable). 
o Intrauterine device. 
o Intrauterine hormone-releasing system  
o Vasectomised partner. 
o Abstinence as a form of birth control is generally not allowed in the study unless 
abstinence is in accordance with a subject’s preferred and common lifestyle. Study 
personnel must confirm the continued use of abstinence is still in accordance with the 
subject’s lifestyle at regular intervals during the study. 
9. Subject agrees not to change their usual sun exposure during the course of the study and to 
use ultraviolet A/ultraviolet B sunscreens if unavoidable exposure occurs. 
6.2 
Exclusion criteria 
Subjects are not permitted to enroll in the study if any of the following criteria are met: 
1. Female subject who is breastfeeding, pregnant, or plans to become pregnant during the study 
or within 20 weeks following the final dose of IMP. 
2. Subject has previously participated in a bimekizumab clinical study who received at least 
1 dose of the IMP (including placebo). 
3a  Subject is currently participating in another study of a medication (systemic) under 
investigation. Subject must be washed out of the medication for 12 weeks or at least 5 half-
lives prior to the Baseline Visit, whichever is greater. 
4a. Subject is currently participating in another study of a topical medication under investigation. 
Subject must be washed out of the medication for 4 weeks prior to the Baseline Visit. 
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5a. Subject is currently, or was within the 4 weeks prior to the Baseline Visit, participating in    
another study of a medical device under investigation. 
6. Subject has a known hypersensitivity to any excipients of bimekizumab or adalimumab. 
7. Subject has a form of PSO other than chronic plaque-type (eg, pustular, erythrodermic and 
guttate PSO, or drug-induced PSO). 
8. Subject has an active infection or history of infection(s) as follows: 
 Any active infection (except common cold) within 14 days prior to Baseline. 
 A serious infection, defined as requiring hospitalization or iv anti-infective(s) within 
2 months prior to the Baseline Visit. 
 A history of opportunistic, recurrent or chronic infections that, in the opinion of the 
Investigator, might cause this study to be detrimental to the subject. Opportunistic 
infections are infections caused by uncommon pathogens (eg, pneumocystis jirovicii, 
cryptococcosis) or unusually severe infections caused by common pathogens (eg, 
cytomegalovirus, herpes zoster). 
9. Subject has concurrent acute or chronic viral hepatitis B or C or human immunodeficiency 
virus (HIV) infection. Subjects who have evidence of, or tested positive for hepatitis B or 
hepatitis C are excluded. A positive test for the hepatitis B virus is defined as: 1) positive for 
hepatitis B surface antigen (HBsAg+) or 2) positive for anti-hepatitis B core antibody 
(HBcAb+). A positive test for the hepatitis C virus (HCV) is defined as: 1) positive for 
hepatitis C antibody (anti-HCV Ab) and 2) positive via a confirmatory test for HCV (for 
example, HCV polymerase chain reaction). 
10. Subject has received any live (includes attenuated) vaccination within the 8 weeks prior to 
the Baseline visit (eg, inactivated influenza and pneumococcal vaccines are allowed but nasal 
influenza vaccination is not permitted). 
11. Subject has received Bacillus Calmette-Guerin vaccinations within 1 year prior to the 
Baseline Visit. 
12. Subject has known tuberculosis (TB) infection, is at high risk of acquiring TB infection, or 
has current or history of nontuberculous mycobacterium (NTMB) infection. A subject with 
LTB (a positive interferon-gamma release assay [IGRA] and diagnosis confirmed by TB 
specialist) may be rescreened once and enrolled after receiving at least 8 weeks of 
appropriate LTB infection therapy and if no evidence of therapy-related hepatotoxicity has 
occurred prior to the first injection (alanine aminotransferase [ALT]/aspartate 
aminotransferase [AST] remain ≤3 times upper limit of normal [ULN]). 
     Subject has a past history of active TB involving any organ system unless adequately treated 
according to World Health Organization/Centers for Disease Control (CDC) therapeutic 
guidance and proven to be fully recovered upon consult with a TB specialist. 
Refer to Section 12.3.1 for details on determining full TB exclusion criteria. 
13. Subject has a history of a lymphoproliferative disorder including lymphoma or current signs 
and symptoms suggestive of lymphoproliferative disease. 
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14a. Subject has any active malignancy or history of malignancy within 5 years prior to the 
Screening Visit EXCEPT treated and considered cured cutaneous squamous or basal cell 
carcinoma, or in situ cervical cancer. 
15. Subject has a diagnosis of inflammatory conditions other than PSO or PsA, including but not 
limited to rheumatoid arthritis, sarcoidosis, or systemic lupus erythematosus. Subjects with a 
diagnosis of Crohn’s disease or ulcerative colitis are allowed as long as they have no active 
symptomatic disease at Screening or Baseline. 
16. Subject has had major surgery (including joint surgery) within the 3 months prior to the 
Baseline Visit, or has planned major surgery within 6 months after entering the study. 
17a.Subject has any systemic disease (ie, cardiovascular, neurological, renal, liver, metabolic, 
gastrointestinal, hematological, immunological, etc.) considered by the Investigator to be 
uncontrolled, unstable, or likely to progress to a clinically significant degree during the 
course of the study. 
18. Subject has had myocardial infarction or stroke within the 6 months prior to the Screening 
Visit. 
19. Subject has laboratory abnormalities at Screening, including any of the following: 
a. ≥3.0x ULN of any of the following: ALT, AST, alkaline phosphatase (ALP); or >ULN 
total bilirubin (≥1.5xULN total bilirubin if known Gilbert’s syndrome) 
b. White blood cell (WBC) count <3.00x103/μL 
c. Absolute neutrophil count <1.5x103/μL 
d. Lymphocyte count <500 cells/μL 
e. Hemoglobin <8.5g/dL 
f. Any other laboratory abnormality, which, in the opinion of the Investigator, will prevent 
the subject from completing the study or will interfere with the interpretation of the study 
results 
Individual screening tests for which the results are in error, borderline, or indeterminate for 
inclusion in the study can be repeated once for confirmation during the Screening Period. Upon 
retesting, subjects whose results remain outside this threshold should not be randomized. 
20. Subject has any other condition, including medical or psychiatric, which, in the Investigator's 
judgment, would make the subject unsuitable for inclusion in the study. 
21. Subject has had previous exposure to adalimumab. 
22. Criterion deleted 
23. Subject has experienced primary failure (no response within 12 weeks) to 1 or more IL-17 
biologic response modifier (eg, brodalumab, ixekizumab, secukinumab) OR more than 1 
biologic response modifier other than an IL-17. 
24. Subject is taking PsA medications other than stable doses (ie, stable for at least 1 week prior 
to the Screening Visit) of nonsteroidal anti-inflammatory drugs (NSAIDs) or analgesics (see 
Section 7.8.1.2). 
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25. Subject has a history of chronic alcohol or drug abuse within 6 months prior to Screening as 
evaluated by the Investigator based on medical history, site interview, and/or results of the 
specified urine drug screen. 
26. Presence of active suicidal ideation, or positive suicide behavior using the “Screening” 
version of the electronic Columbia Suicide Severity Rating Scale (eC-SSRS) and with either 
of the following criteria: 
 History of a suicide attempt within the 5 years prior to the Screening Visit. Subjects with 
a history of a suicide attempt more than 5 years ago should be evaluated by a mental 
healthcare practitioner (HCP) before enrolling into the study. 
 Suicidal ideation in the past month prior to the Screening Visit as indicated by a positive 
response (“Yes”) to either Question 4 or Question 5 of the “Screening” version of the 
eC-SSRS. 
27a. Subject has presence of moderately severe major depression or severe major depression, 
indicated by a score of ≥15 using the screening PHQ-9. Medication used to treat depression 
should be stable for 8 weeks prior to Baseline. 
28. Subject is a member of Investigator site personnel directly affiliated with this study and/or 
their immediate families. Immediate family is defined as a spouse, parent, child, or sibling, 
whether biological or legally adopted. 
29. Subject is a UCB employee or employee of third-party organizations involved in the study. 
30. Subject is taking or has taken prohibited psoriasis medications without meeting the 
mandatory washout period relative to the Baseline Visit (Table 7‒2). 
6.3 
Withdrawal criteria 
Subjects are free to withdraw from the study at any time, without prejudice to their continued 
care. Subjects who withdraw from the study should complete the PEOT Visit (see Section 8.4). 
Subjects should be withdrawn from the study and will be encouraged to come back for the SFU 
visit 20 weeks after final dose of IMP if the subject withdraws his/her consent or the Sponsor or 
a regulatory agency requests withdrawal of the subject. 
A subject should be withdrawn from IMP and will be asked to come back for the SFU visit 
20 weeks after final dose of IMP if any of the following events occur: 
1. Subject develops an illness that in the opinion of the Investigator would interfere with his/her 
continued participation if the risk of continuing IMP outweighs the potential benefit. 
2. Subject develops erythrodermic, guttate, or pustular form of PSO. 
3. Criterion deleted 
4. Subject is noncompliant with the study procedures or medications in the opinion of the 
Investigator. 
5. Subject uses prohibited concomitant medications, with the exception of topicals, as defined 
in this protocol (Section 7.8.2), that may present a risk to the safety of the subject or the 
integrity of the study data, in the opinion of the Investigator and/or the Medical Monitor. 
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6. Subject has a clinical laboratory value meeting any of the following criteria: 
a. Hepatotoxicity as described in Section 6.3.1 
b. A laboratory value meeting any of the following criteria: 
 Absolute neutrophil count <1.0x103/μL 
 Absolute lymphocyte count <0.2x103/μL 
Subjects may remain in the study if the result is transient. A retest is required within 1 to 2 weeks 
at a scheduled or unscheduled visit. If the repeat absolute neutrophil count or absolute 
lymphocyte count is still below the allowable values, the subject must be withdrawn. If the 
repeat absolute neutrophil count or absolute lymphocyte count is above the allowable values, the 
subject may continue in the study. 
7. The subject experiences a severe AE, an SAE, or a clinically significant change in a 
laboratory value that, in the opinion of the Investigator, merits the discontinuation of the IMP 
and appropriate measures being taken. 
8. At Week 28 and all following visits, subjects on continuous treatment with the same IMP for 
at least 12 weeks with a persistent IGA score ≥3 over at least a 4-week period are defined as 
nonresponders and should discontinue IMP. 
9. There is confirmation of a pregnancy during the study, as evidenced by a positive pregnancy 
test (see Section 12.1.4 for more information regarding pregnancies). 
10. A subject considered as having either a suspected new LTB infection or who develops active 
TB or NTMB infection during the study (including but not limited to, conversion 
demonstrated by IGRA or other diagnostic means) must be immediately discontinued from 
IMP and a PEOT Visit must be scheduled as soon as possible, but not later than the next 
regular visit. 
The subject must be permanently withdrawn if further examinations result in a diagnosis of 
active TB, or if the subject is diagnosed with latent TB infection (LTBI) with no initiation of 
prophylactic treatment, prematurely discontinues prophylactic treatment, or, in the opinion of 
the Investigator or Sponsor, is noncompliant with prophylactic TB therapy. 
Confirmed active TB is an SAE and must be captured on an SAE Report Form and provided 
to the Sponsor in accordance with SAE reporting requirements. As with all SAEs, periodic 
follow-up reports should be completed as per protocol requirements until such time as the TB 
infection resolves. 
Additional information on TB policies is provided in Section 12.3.1. 
11. Subjects with newly diagnosed inflammatory bowel disease (IBD) or with IBD flares during 
the study must: 
 Be referred, as appropriate, to a health care professional treating IBD, such as a 
gastroenterologist 
 Discontinue IMP and be followed-up until resolution of active IBD symptoms 
If IBD flares increase in severity or frequency during the study, the Investigator should use 
clinical judgement in deciding whether the subject should continue in the study and contact the 
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Medical Monitor and UCB study physician to confirm the subject’s suitability for continued 
participation in the study. 
12. Subjects must be referred immediately to a mental health care professional and may be 
withdrawn from the study based upon the Investigator’s judgment of benefit/risk for: 
 Active suicidal ideation as indicated by a positive response (“Yes”) to Question 4 of 
the “Since Last Visit” version of the eC-SSRS. 
 Moderately severe major depression as indicated by a PHQ-9 score of 15 to 19 if this 
represents an increase of 3 points compared to last visit. 
13. Subjects must be referred immediately to a mental healthcare professional and must be 
withdrawn in case of: 
 Active suicidal ideation as indicated by a positive response ("Yes") to Question 5 of the 
"Since Last Visit" version of the eC-SSRS  
 Any suicidal behavior since last visit. 
 Severe major depression as indicated by a PHQ-9 score ≥20. 
The mental health consultation must be recorded in source documentation. 
Investigators should attempt to obtain information on subjects in the case of withdrawal or 
discontinuation. For subjects considered as lost to follow-up, the Investigator should make an 
effort (at least 1 phone call and 1 written message to the subject), and document his/her effort 
(date and summary of the phone call and copy of the written message in the source documents), 
to complete the final evaluation. All results of these evaluations and observations, together with a 
narrative description of the reason(s) for removing the subject, must be recorded in the source 
documents. The electronic Case Report Form (eCRF) must document the primary reason for 
withdrawal or discontinuation. 
Investigators should contact the Medical Monitor, whenever possible, to discuss the withdrawal 
of a subject in advance. 
6.3.1 
Potential drug-induced liver injury IMP discontinuation criteria 
Subjects with potential drug-induced liver injury (PDILI) must be assessed to determine if IMP 
must be discontinued. In addition, all concomitant medications and herbal supplements that are 
not medically necessary should also be discontinued. 
The PDILI criteria below require immediate and permanent discontinuation of IMP for subjects 
with either of the following: 
 ALT or AST ≥8xULN 
 ALT or AST ≥3xULN and coexisting total bilirubin ≥2xULN 
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The PDILI criterion below requires immediate discontinuation of IMP for: 
 Subjects with ALT or AST ≥3xULN who exhibit temporally associated symptoms of 
hepatitis or hypersensitivity. Hepatitis symptoms include fatigue, nausea, vomiting, right 
upper quadrant pain or tenderness. Hypersensitivity symptoms include fever (without clear 
alternative cause), rash, or eosinophilia (ie, >5%). 
If a nondrug-related cause for the symptoms can be confirmed, these subjects may resume 
IMP administration after discussion with the responsible UCB physician, but only when the 
requirements for rechallenge with IMP as provided in Section 12.2.1.2.1 are followed. 
The PDILI criterion below allows for subjects to continue on IMP at the discretion of the 
Investigator. 
 Subjects with ALT or AST ≥5xULN and <8xULN, total bilirubin <2xULN, and no 
eosinophilia (ie, ≤5%), with no fever, rash, or symptoms of hepatitis (eg, fatigue, nausea, 
vomiting, right upper quadrant pain, or tenderness). 
Evaluation of PDILI must be initiated as described in Section 12.2.1 with repeat tests 
performed in 2 weeks. Upon re-test, if ALT or AST values have reduced to <5xULN, the 
subject can continue with the study. However, if ALT or AST remains ≥5xULN and 
<8xULN after re-test, IMP should be temporarily withheld and subject should undergo a 
repeat test in 2 weeks. If ALT or AST values remain ≥5xULN even after the second re-test, 
then the subject should be permanently withdrawn from the study and should be followed for 
possible drug-induced liver injury. 
If subjects are unable to comply with the applicable monitoring schedule, IMP must be 
discontinued immediately. 
Investigators should attempt to obtain information on subjects in the case of IMP discontinuation 
to complete the final evaluation. Subjects with PDILI should not be withdrawn from the study 
until investigation and monitoring are complete. All results of these evaluations and 
observations, as well as the reason(s) for IMP discontinuation and subject withdrawal (if 
applicable), must be recorded in the source documents. The eCRF must document the primary 
reason for IMP discontinuation. 
7 
STUDY TREATMENT(S) 
7.1 
Description of investigational medicinal product(s) 
The IMPs used in this study are bimekizumab, adalimumab, and placebo. 
 Bimekizumab will be supplied in a 1mL prefilled syringe (PFS) at a concentration of 
 for sc 
injection. 
 Adalimumab is commercially available and will be supplied as a PFS for sc injection (at a 
concentration of 40mg/0.8mL or 40mg/0.4mL depending on regional availability) in a single-
use syringe. 
 Placebo will be supplied as 0.9% sodium chloride aqueous solution (physiological saline, 
preservative-free) of pharmacopoeia (USP/Ph.Eur) quality in a 1mL PFS for sc injection. 
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Further details of the IMPs and their specifications are provided in the IMP Handling Manual. 
7.2 
Treatment(s) to be administered 
Unblinded study staff will be responsible for preparation of the clinical study material, including 
recording the administration information on source documents, and administration of the IMP as 
sc injections. The unblinded personnel will not be involved in the study in any way other than 
assuring the medication is taken from the correct kit and administering the IMP to the subjects. 
Suitable areas for sc injections are the lateral abdominal wall and upper outer thigh. During each 
dosing visit, each of the injections should be administered at a separate injection site. Injection 
sites should be rotated at each visit and injections should not be given into a PSO plaque or areas 
where the skin is tender, bruised, erythematous, or indurated. The injection should last 
approximately 10 to 15 seconds. 
An IMP Handling Manual will be provided to each site containing instructions regarding drug 
preparation and dosing.  
Eligible subjects will be randomized 1:1:1 to receive the following blinded study treatment 
regimens: bimekizumab 320mg Q4W throughout the study, bimekizumab 320mg Q4W until 
Week 16, or adalimumab. 
Because of differences in the dosing schedule between bimekizumab and adalimumab and in 
order to maintain blinding, all subjects will receive 2 injections sc on Weeks 0 (Baseline), 4, 8, 
12, 16, 20, and 24, and 1 injection sc in other weeks: 
 Subjects randomized to receive bimekizumab 320mg Q4W throughout the study will receive 
2 bimekizumab 160mg injections sc Q4W at Weeks 0 (Baseline), 4, 8, 12, 16, 20, 24, 28, 32, 
36, 40, 44, 48, and 52. These subjects will receive 1 placebo injection at Weeks 1, 3, 5, 7, 9, 
11, 13, 15, 17, 19, 21, and 23. 
 Subjects randomized to receive bimekizumab 320mg Q4W/Q8W will receive 2 bimekizumab 
160mg injections sc Q4W at Weeks 0 (Baseline), 4, 8, and 12. Subjects will then receive 
2 bimekizumab 160mg injections sc Q8W at Weeks 16, 24, 32, 40, and 48. These subjects 
will receive 1 placebo injection at Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23, and 
2 placebo injections at Weeks 20, 28, 36, 44, and 52. 
 Subjects randomized to receive adalimumab will receive 2 adalimumab 40mg injections sc at 
Week 0 (Baseline). At Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23, they will receive 
1 adalimumab 40mg injection sc. These subjects will receive 2 placebo injections at 
Weeks 4, 8, 12, 16, and 20. These subjects will then receive bimekizumab 320mg Q4W 
given as 2 bimekizumab 160mg injections sc Q4W at Weeks 24, 28, 32, 36, 40, 44, 48, and 
52. 
The dosing scheme is depicted in Table 7‒1.
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Table 7‒1: 
Dosing scheme 
Week 
Dose Assignment 
0 
1,  
3 
4 
5,  
7 
8 
9, 
11 
12 
13, 
15 
16 
17, 
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
bimekizumab 320mg 
Q4W/Q4W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
bimekizumab 320mg 
Q4W/Q8W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
 
○ 
 
○○ 
○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
adalimumab 
40mg/bimekizumab 
320mg Q4W 
▲▲ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
Q4W=every 4 weeks; Q8W=every 8 weeks 
Notes: A bimekizumab 160mg injection is depicted by a black circle (●). A placebo injection is depicted by a white circle (○). An adalimumab 40mg injection is 
depicted by a black triangle (▲).
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7.3 
Packaging 
Bimekizumab, adalimumab, and placebo will be packaged and labeled according to Good 
Manufacturing Practice (GMP) guidelines and applicable laws or regulations. They will be 
suitably packaged in such a way as to protect the product from deterioration during transport and 
storage. Further information regarding storage and transport conditions are provided in the IMP 
Handling Manual. 
7.4 
Labeling 
Bimekizumab, adalimumab, and placebo will be labeled in accordance with the current 
International Council for Harmonisation (ICH) guidelines on Good Clinical Practice (GCP) and 
GMP and will include any locally required statements. If necessary, labels will be translated into 
the local language. 
7.5 
Handling and storage requirements 
Refer to the IMP Handling Manual for the storage conditions of the IMP. 
The Investigator (or designee) is responsible for the safe and proper storage of IMP at the site. 
Investigational medicinal product stored by the Investigator is to be kept in a secured area with 
limited access according to the storage conditions mentioned on the label. 
Appropriate storage conditions must be ensured either by controlling the temperature (eg, room, 
refrigeration unit) or by completion of a temperature log in accordance with local requirements 
on a regular basis (eg, once a week), showing actual and minimum/maximum temperatures 
reached over the time interval. 
In case an out-of-range temperature is noted, it must be immediately reported as per instructions 
contained in the IMP Handling Manual. 
The IMP will be shipped to the study sites in temperature controlled containers. Out-of-range 
shipping or storage conditions must be brought to the attention of the Sponsor or designee, 
immediately. Authorization to use any out-of-range IMP must be documented and received prior 
to dispensing or administering the IMP at the study site. 
7.6 
Drug accountability 
A Drug Accountability Form will be used to record IMP dispensing and return information on a 
by subject basis and will serve as source documentation during the course of the study. Details of 
any IMP lost, damaged (eg, due to breakage or wastage), not used, partially used, disposed of at 
the study site, or returned to the Sponsor or designee must also be recorded on the appropriate 
forms. All supplies and pharmacy documentation must be made available throughout the study 
for UCB (or designee) to review. 
In order to maintain the blind, all IMP documentation (eg, shipping receipts, drug accountability 
logs, Interactive Response Technology (IRT) randomization materials) must be maintained and 
accessed by unblinded, trained site personnel only. Designated, unblinded site personnel must be 
appropriately trained and licensed (per country guidelines) to administer injections. 
Unblinded study staff will be delegated the responsibility to receive, inventory and destroy the 
used kits. The packaging identifies each kit by a unique number, but due to the commercial 
packaging of the comparator, the unblinded study staff will be responsible in order to maintain 
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the blind. Unblinded study staff will be responsible for preparation (breaking tamper proof 
sticker on kit, etc) of the clinical study material, including recording the administration 
information on source documents. 
The Investigator (or designee) is responsible for retaining all used, unused, and partially used 
containers of IMP until returned or destroyed. 
The Investigator may assign some of the Investigator’s duties for drug accountability at the study 
site to an appropriate pharmacist/designee. 
The Investigator must ensure that the IMP is used only in accordance with the protocol. 
Periodically, and/or after completion of the clinical phase of the study, all used (including empty 
containers)/partially used, unused, damaged, and/or expired IMP must be reconciled and either 
destroyed at the site according to local laws, regulations, and UCB Standard Operating 
Procedures (SOPs) or returned to UCB (or designee). Investigational medicinal product intended 
for the study cannot be used for any other purpose than that described in this protocol. 
7.7 
Procedures for monitoring subject compliance 
During the Treatment Period of this study, the IMP will be administered in the clinic and 
compliance will be determined at the visit by study personnel. Drug accountability must be 
recorded on the Drug Accountability Form. 
7.8 
Concomitant medication(s)/treatment(s) 
Any treatment administered from the time of informed consent to the final study visit will be 
considered concomitant medication. This includes medications that were started before the study 
and are ongoing during the study. 
7.8.1 
Permitted concomitant treatments (medications and therapies) 
7.8.1.1 
Topical medications 
Subjects may continue to use topical moisturizers or emollients, bath oils, or oatmeal bath 
preparations for skin conditions during the study, as needed. Over-the-counter shampoos for the 
treatment of PSO of the scalp are also permitted. 
Mild and low potency topical steroids will be permitted for use limited to the face, axilla, and/or 
genitalia, as needed. These topical medications should not be used within approximately 
24 hours prior to study visits requiring IGA and PASI measures. 
7.8.1.2 
Other medications 
Subjects who are already receiving an established NSAID regimen for PsA or symptoms of 
arthritis and have been on a stable dose for at least 1 week prior to the Screening Visit may 
continue their use during the study. However, initiation of, or increase in dosage of NSAIDs 
during the study (especially in subjects with a history of gastrointestinal (GI) intolerance to 
NSAIDs or a history of GI ulceration) should not occur prior to Week 24 and should not happen 
within 2 weeks of the Week 56 Visit. 
Subjects may take mild pain relievers (acetaminophen/paracetamol, mild opiates) as needed for 
arthritis pain but preferably not within 24 hours of the Baseline and Week 56 Visits. 
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Intra-articular steroid injections of any joint and hyaluronic acid injections are allowed after 
Week 24. 
Subjects who are receiving an established regimen for depression should remain on stable dosing 
prior to Baseline and throughout the study. 
7.8.2 
Prohibited concomitant treatments (medications and therapies) 
Table 7‒2 presents the list of prohibited medications. 
Table 7‒2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
Topicals except for those permitted (Section 7.8.1.1) 
2 weeks 
Systemic retinoids 
3 months  
Systemic treatment (nonbiological): 
systemic immunosuppressant agents (eg, 
methotrexate, cyclosporine, azathioprine, 
thioguanine) 
fumaric acid esters specifically used for the 
treatment of PSO 
systemic corticosteroids 
phototherapy  
1 month 
Anti-TNFs: 
adalimumab (including biosimilar) 
etanercept (including biosimilar) 
infliximab (including biosimilar), golimumab, 
certolizumab pegol 
 
Any exposure to adalimumab 
1 month for etanercept 
3 months for infliximab (including biosimilar), 
golimumab, certolizumab pegol 
Other biologics and other systemic therapies, eg: 
 
apremilast, tofacitinib 
2 weeks for apremilast and tofacitinib 
alefacept, efalizumab, guselkumab 
3 months for alefacept, efalizumab, and 
guselkumab 
tildrakizumab, risankizumab 
5 months for tildrakizumab and risankizumab 
ustekinumab, briakinumab 
6 months for ustekinumab and briakinumab 
rituximab 
12 months for rituximab 
Anti-IL-17 therapy: 
brodalumab 
ixekizumab 
secukinumab 
3 months 
(bimekizumab is excluded per exclusion 
criteria) 
Any other antipsoriatic agent (systemic) under 
investigation (or approved after the protocol is 
approved) 
3 months or 5 half-lives, whichever is greater 
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Table 7‒2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
Any other antipsoriatic agent (topical) under 
investigation 
1 month 
IL-17=interleukin 17; PSO=psoriasis; TNF=tumor necrosis factor 
Subjects who take prohibited medications may be withdrawn from IMP but followed until the 
SFU Visit. The decision to withdraw a subject for taking prohibited medications should be made 
in consultation with the Medical Monitor. 
7.8.2.1 
Vaccines 
Administration of live (including attenuated) vaccines is not allowed during the conduct of the 
study and for 20 weeks after the final dose of the IMP (see Exclusion Criterion #10, Section 6.2). 
Administration of inactivated vaccines is allowed during the study at the discretion of the 
Investigator. 
7.9 
Blinding 
Due to differences in presentation between the bimekizumab and adalimumab, special 
precautions will be taken to ensure study blinding and study sites will have blinded and 
unblinded personnel. 
All Sponsor and Investigator site personnel involved in the study will be blinded to the 
randomized IMP assignment with the following exceptions: 
 Unblinded study staff will be responsible for preparation (breaking tamper proof sticker on 
kit, etc) of the clinical trial material, including recording the administration information on 
source documents, and administration of the IMP as sc injections. The unblinded personnel 
will not be involved in the study in any way other than assuring the medication is taken from 
the correct kit and administering the drug to the subjects. 
 Bioanalytical staff analyzing blood samples for bimekizumab and anti-bimekizumab 
antibody determination. 
During the study, the Sponsor will provide blinded and unblinded site monitors for the purposes 
of verifying safety, efficacy, and drug administration and documentation records. Unblinded 
study site personnel need to be available in order to resolve queries. Study monitors and study 
site personnel blinded to treatment assignment will not discuss or have access to any drug-related 
information. 
Study sites will be required to have a written blinding plan in place, signed by the Principal 
Investigator, which will detail the site’s steps for ensuring that the double-blind nature of the 
study is maintained. Sites will be instructed to keep study subjects blind to the IMP as detailed in 
the site blinding plan. 
Further details are provided in the study manual and site blinding plan. 
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7.9.1 
Procedures for maintaining and breaking the treatment blind 
7.9.1.1 
Maintenance of IMP blind 
All subject treatment details (bimekizumab or adalimumab) will be allocated and maintained by 
the IRT system. 
7.9.1.2 
Breaking the treatment blind in an emergency situation 
The integrity of this clinical study must be maintained by observing the treatment blind. In the 
event of an emergency for which the appropriate treatment for a subject cannot be made without 
knowing the treatment assignment, it will be possible to determine to which treatment arm and 
dose the subject has been allocated by contacting the IRT. All sites will be provided with details 
of how to contact the system for code breaking at the start of the study. The Medical Monitor or 
equivalent should be consulted prior to unblinding, whenever possible. 
The Clinical Project Manager (CPM) will be informed immediately via the IRT when a code is 
broken, but will remain blinded to specific treatment information. Any unblinding of the IMP 
performed by the Investigator must be recorded in the source documents and on the Study 
Termination eCRF page. 
7.10 
Randomization and numbering of subjects 
An IRT will be used for assigning eligible subjects to a treatment regimen based on a 
predetermined production randomization and/or packaging schedule provided by UCB (or 
designee). The randomization schedule will be produced by the IRT vendor. The IRT will 
generate individual assignments for subject kits of IMP, as appropriate, according to the visit 
schedule. Subject treatment assignment will be stratified by region (North America, Western 
Europe, Central/Eastern Europe and Asia/Australia) and prior biologic exposure (yes/no). The 
IRT will generate individual assignments for subject kits of IMP, as appropriate, according to the 
visit schedule. 
At Screening, each subject will be assigned a 5-digit number that serves as the subject identifier 
throughout the study. The subject number will be required in all communication between the 
Investigator or designee and the IRT regarding a particular subject. 
At the Baseline Visit, a subject will be randomized into the study. The Investigator or designee 
will use the IRT for randomization. The IRT will automatically inform the Investigator or 
designee of the subject’s identification number. The IRT will allocate kit numbers to the subject 
based on the subject number during the course of the study. The kits are blinded. 
Subject numbers and kit numbers will be tracked via the IRT. 
8 
STUDY PROCEDURES BY VISIT 
Table 5‒1 (Schedule of study assessments) provides a general overview of study assessments. A 
list of procedures to be completed at each visit is described below. 
 From the Week 1 Visit to the Week 24 Visit, visit windows of ±3 days on either side of the 
scheduled dosing are permitted; however, the Investigator should try to keep the subjects on 
the original dosing schedule. From the Week 28 Visit to the Week 52 Visit, visit windows are 
±7 days. Changes to the dosing schedule outside of the visit window must be discussed with 
the Medical Monitor. 
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 The dosing window is ±3 days relative to the scheduled dosing visit through Week 24. The 
dosing window is ±7 days relative to the scheduled dosing visit from Week 28 through the 
end of the study. 
 For the SFU Visit (20 weeks after the final dose), the visit window is ±7 days relative to the 
scheduled visit date. 
8.1 
Screening Visit (2 to 5 weeks) 
Prior to any study specific activities, subjects will be asked to read, sign, and date an ICF that has 
been approved by the Sponsor and an Institutional Review Board (IRB)/Independent Ethics 
Committee (IEC), and that complies with regulatory requirements. Subjects will be given 
adequate time to consider any information concerning the study given to them by the Investigator 
or designee. As part of the informed consent procedure, subjects will be given the opportunity to 
ask the Investigator any questions regarding potential risks and benefits of participation in the 
study. 
Where local regulations permit, subjects will also be given the option to participate in the 
genomics, genetics, and proteomics substudy. Subjects agreeing to participate in the substudy 
will be required to complete a separate ICF. The ICF must be signed prior to collecting any 
samples for the substudy. The substudy will only be conducted where ethically accepted and 
authorized by the regulatory agencies. Refusal to participate in the substudy will not affect a 
subject’s ability to participate in the main PS0008 study. 
The following procedures or assessments will be performed at the Screening Visit: 
 Obtain written informed consent 
 Assessment of inclusion and exclusion criteria 
 Urine drug screen 
 Demographic data (age, gender, race, and ethnicity [according to local regulations]) 
 Psoriasis history including the date of onset and past treatments 
 Significant past medical history including clinically relevant past or coexisting medical 
conditions and surgeries 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Vital signs (sitting systolic and diastolic blood pressure [BP], pulse rate, and body 
temperature) should be obtained prior to blood sampling 
 Collect blood and urine samples for the following clinical laboratory tests: 
 Hematology and biochemistry 
 Urinalysis 
 Serum pregnancy test for women of childbearing potential 
 Hepatitis B and Hepatitis C 
 HIV 
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 IGRA tuberculosis test; it is recommended that the QuantiFERON TB test be performed 
 Record 12-lead ECG 
 Chest x-ray (not necessary if performed within 3 months prior to Screening Visit and report 
is available) 
 TB questionnaire 
 PASI 
 IGA 
 Percentage of BSA 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Confirm subject eligibility and contact the IRT 
8.2 
Initial Treatment Period 
8.2.1 
Baseline Visit 
The following procedures or assessments will be performed/recorded at the Baseline Visit prior 
to administration of the IMP: 
 Re-assessment of inclusion and exclusion criteria 
 Significant past medical history and concomitant diseases to ensure no significant changes 
since screening 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Height 
 Body weight 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
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 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only)  
 Genetic/epigenetic analyses (participating subjects only) 
 TB questionnaire 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptoms Diary 
 scalp IGA 
 mNAPSI 
 pp-IGA 
 EQ-5D-3L 
 SF-36 
 PASE 
 PGADA  
 WPAI-SHP V2.0 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or 
adalimumab will occur. 
8.2.2 
Week 1 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Bimekizumab plasma concentrations 
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 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.2.3 
Week 3 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Bimekizumab plasma concentrations 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
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After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.2.4 
Week 4 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline  
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
 PGADA for subjects with PsA at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.2.5 
Week 5 and 7 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
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 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.2.6 
Week 8 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
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 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.2.7 
Week 9 and 11 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.2.8 
Week 12 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Body weight 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 Record 12-lead ECG 
 TB questionnaire 
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 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
 PGADA for subjects with PsA at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.2.9 
Week 13 and 15 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.2.10 
Week 16 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
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 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 Urinalysis 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
 PGADA  
 WPAI-SHP V2.0 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, the Maintenance Treatment Period will 
begin with administration of bimekizumab or placebo. 
8.3 
Dose-blind Maintenance Treatment Period 
8.3.1 
Week 17 and 19 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
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 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.3.2 
Week 20 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
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After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.3 
Week 21 and 23 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of adalimumab or placebo 
will occur. 
8.3.4 
Week 24 (±3 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Body weight 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 TB questionnaire 
 Record 12-lead ECG 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
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 PHQ-9 
 eC-SSRS 
 Daily Patient Symptom Diary 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
 Patient global assessment of PSO 
 PGADA  
 WPAI-SHP V2.0 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.5 
Week 28 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain urine sample for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urine pregnancy test 
 PASI 
 IGA 
 Percentage of BSA 
 PHQ-9 
 eC-SSRS 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
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After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.6 
Week 32 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 Patient global assessment of PSO 
 PGADA for subjects with PsA at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.7 
Week 36 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Body weight 
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 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 TB questionnaire 
 Record 12-lead ECG 
 PASI 
 IGA 
 Percentage of BSA 
 PHQ-9 
 eC-SSRS 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.8 
Week 40 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
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 pp-IGA for subjects with palmoplantar involvement at Baseline 
 PHQ-9 
 eC-SSRS 
 EQ-5D-3L 
 SF-36 
 Patient global assessment of PSO 
 PGADA for subjects with PsA at Baseline 
 WPAI-SHP V2.0 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.9 
Week 44 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain urine sample for the following analyses prior to dosing: 
 Urine pregnancy test 
 PASI 
 IGA 
 Percentage of BSA 
 PHQ-9 
 eC-SSRS 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.10 
Week 48 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
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 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Body weight 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 Record 12-lead ECG 
 TB questionnaire 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 PHQ-9 
 eC-SSRS 
 Patient global assessment of PSO 
 PGADA for subjects with PsA at Baseline 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.11 
Week 52 (±7 days) 
The following procedures or assessments will be performed/recorded prior to administration of 
the IMP: 
 Obtain informed consent for the open-label study 
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 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Urine pregnancy test 
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB test be performed  
 PASI 
 Percentage of BSA 
 IGA 
 PHQ-9 
 eC-SSRS 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
8.3.12 
Week 56 (±7 days) 
The following procedures or assessments will be performed/recorded: 
 Urine drug screen 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Body weight 
 Vital signs (sitting systolic and diastolic BP, pulse rate, and body temperature) should be 
obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 Genetic/epigenetic analyses (participating subjects only) 
 Record 12-lead ECG 
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 TB questionnaire 
 PASI 
 IGA 
 Percentage of BSA 
 DLQI 
 PHQ-9 
 eC-SSRS 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
 pp-IGA for subjects with palmoplantar involvement at Baseline 
 EQ-5D-3L 
 SF-36 
 Patient global assessment of PSO 
 PASE 
 PGADA for subjects with PsA at Baseline 
 WPAI-SHP V2.0 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
8.4 
Premature End of Treatment Visit 
If a subject is withdrawn from the study: 
 The subject will be withdrawn from IMP, will undergo the same assessments as the 
Week 56 visit (see Section 8.3.12), and will enter the SFU Period. 
 The subject will be encouraged to return for the SFU Visit (20 weeks after the last 
received dose; see Section 8.5). 
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8.5 
Safety Follow-Up Visit (20 weeks after final dose ±7 days) 
All subjects not continuing in the open-label study, including those withdrawn from study 
treatment, will have a SFU Visit 20 weeks after their final dose of IMP. The following 
procedures or assessments will be performed/recorded: 
 Physical examination, including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
 Vital signs (sitting systolic and diastolic blood pressure, pulse rate, and body temperature) 
should be obtained prior to blood sampling 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Hematology and biochemistry 
 Urinalysis 
 Urine pregnancy test 
 Bimekizumab plasma concentrations 
 Anti-bimekizumab antibodies 
 TB questionnaire 
 PASI 
 IGA 
 Percentage of BSA 
 eC-SSRS 
 Concomitant medications 
 Record AEs 
 Contact the IRT 
8.6 
Unscheduled Visit 
At the Investigator’s discretion, an Unscheduled Visit may be completed at any time during the 
study but prior to the SFU Visit, if deemed necessary for the subject’s safety and well-being. 
If an Unscheduled Visit is conducted due to safety or efficacy reasons, an eC-SSRS assessment 
will be performed with the subject during the visit. If an Unscheduled Visit is conducted for 
reasons other than safety or efficacy concerns (eg, repeated collection of a laboratory specimen 
due to collection or analysis issues), an eC-SSRS will not be required at these visits. 
At this visit, any assessment may be performed, as needed, depending on the reason for the visit. 
9 
ASSESSMENT OF EFFICACY 
The PASI, BSA, IGA, scalp IGA, mNAPSI, and pp-IGA should be performed by the 
Investigator, another delegated physician, or an appropriately qualified medical professional 
(based on local requirements) who has had documented training on how to perform these 
assessments correctly. The same assessor should evaluate the subject at each assessment. 
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9.1 
Psoriasis Area and Severity Index 
The PASI is the most commonly used and validated assessment for grading the severity of PSO 
in clinical studies (Feldman, 2004). The PASI quantifies the severity and extent of the disease 
and weighs these with the percentage of BSA involvement. 
The percent area of involvement (BSA%) is estimated across 4 body areas; head, upper 
extremities, trunk, and lower extremities. Assessors will enter the degree of involvement for a 
given region on a scale of 0 to 6 (0=none; 1=1% to <10% affected, 2=10% to <30% affected, 
3=30% to <50% affected, 4=50% to <70% affected, 5=70% to <90% affected, 6=90% to 100% 
affected) (Table 9‒3). 
The Investigator assesses the average redness, thickness, and scaliness of lesions in each body 
area (each on a 5-point scale); 0=none, 1=slight, 2=moderate, 3=marked, and 4=very marked. 
The PASI score ranges from 0 to 72 with a higher score indicating increased disease severity. 
Table 9‒3: 
Body areas for calculation of percent BSA for PASI 
Body area 
Details of area 
BSA 
Degree of 
involvement of 
body area
a 
Head 
Face, back of head 
10% 
0 to 6 
Upper extremities 
Left, right, upper lower, flexor 
surface, extensor surface 
20% 
0 to 6 
Trunk 
Front, back, groin 
30% 
0 to 6 
Lower extremities 
Left, right, upper lower, flexor 
surface, extensor surface, including 
buttocks 
40% 
0 to 6 
Total 
 
100% 
 
BSA=body surface area; PASI=Psoriasis Area and Severity Index 
a Where 0=none; 1=1% to <10% affected; 2=10% to <30% affected; 3=30% to <50% affected; 4=50% to <70% 
affected; 5=70% to <90% affected; 6=90% to 100% affected 
The PASI50, PASI75, PASI90, and PASI100 responses are based on at least 50%, 75%, 90%, 
and 100% improvement in the PASI score, respectively. 
The total BSA affected by PSO will be entered as a percentage from 0 to 100. 
The PASI will be completed at the visits specified in Table 5‒1. 
9.2 
Investigator’s Global Assessment 
A static IGA for PSO will be used to assess disease severity in all subjects during the study. The 
IGA will be completed at the visits specified in Table 5‒1. 
The Investigator will assess the overall severity of PSO using the following 5-point scale 
presented in Table 9‒4. 
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Table 9‒4: 
Five-point IGA 
Score 
Short Descriptor 
Detailed Descriptor 
0 
Clear 
No signs of PSO; post-inflammatory hyperpigmentation may be present 
1 
Almost clear 
No thickening; normal to pink coloration; no to minimal focal scaling 
2 
Mild 
Just detectable to mild thickening; pink to light red coloration; 
predominately fine scaling 
3 
Moderate 
Clearly distinguishable to moderate thickening; dull to bright red, 
moderate scaling 
4 
Severe 
Severe thickening with hard edges; bright to deep dark red coloration; 
severe/coarse scaling covering almost all or all lesions 
IGA=Investigator’s Global Assessment; PSO=psoriasis 
9.3 
Dermatology Life Quality Index 
The DLQI is a questionnaire designed for use in adult subjects with PSO. The DLQI is a skin 
disease-specific questionnaire aimed at the evaluation of how symptoms and treatment affect 
subjects’ health related QOL. This instrument asks subjects about symptoms and feelings, daily 
activities, leisure, work and school, personal relationships and treatment. It has been shown to be 
valid and reproducible in subjects with PSO. The DLQI score ranges from 0 to 30 with higher 
scores indicating lower health related QOL. A 4-point change in the DLQI score (DLQI 
response) has been reported to be meaningful for the subject (within-subject minimal important 
difference); while a DLQI absolute score of 0 or 1 indicates no or small impact of the disease on 
health related QOL. Subjects will be asked to complete the DLQI as outlined in the Schedule of 
Study Assessments (Table 5‒1). 
9.4 
Patient Health Questionnaire 9 
The PHQ-9 is a multipurpose instrument for screening, diagnosing, monitoring, and measuring 
the severity of depression (Kroenke et al, 2001). The PHQ-9 scores for depression range from 0 
to 27 with higher scores indicating worse state. A score of 5 to 9 is considered to be minimal 
symptoms of depression. A score of 10 to 14 is considered minor depression, dysthymia, or mild 
major depression. A score of 15 to 19 is considered to indicate moderately severe major 
depression, and a score ≥20 is considered to be severe major depression. 
The PHQ-9 will be assessed at the visits specified in Table 5‒1. 
Refer to Section 6.3 for PHQ-9-related withdrawal criteria. 
9.5 
Scalp IGA 
A static IGA for scalp PSO will be used to assess disease severity on the scalp. 
All subjects will complete the scalp IGA at Baseline. Only subjects with scalp involvement at 
Baseline will complete the scalp IGA at the other visits specified in Table 5‒1. Subjects with 
scalp involvement at Baseline are defined as those with a scalp IGA score >0 at Baseline. 
Scalp lesions will be assessed in terms of clinical signs of redness, thickness, and scaliness using 
a 5-point scale (Table 9‒5). 
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Table 9‒5: 
Scalp IGA 
Score 
Short Descriptor 
Detailed Descriptor 
0 
Clear 
Scalp has no signs of PSO; post-inflammatory hyperpigmentation may 
be present 
1 
Almost clear 
Scalp has no thickening; normal to pink coloration; no to minimal focal 
scaling 
2 
Mild 
Scalp has just detectable to mild thickening; pink to light red coloration; 
predominately fine scaling 
3 
Moderate 
Scalp has clearly distinguishable to moderate thickening; dull to bright 
red, moderate scaling 
4 
Severe 
Scalp has severe thickening with hard edges; bright to deep dark red 
coloration; severe/coarse scaling covering almost all or all lesions 
PSO=psoriasis; scalp IGA=scalp-specific Investigator’s Global Assessment 
9.6 
mNAPSI 
Nail PSO will be evaluated using the mNAPSI. All affected nails will be scored (0 to 3) for 
onycholysis/oil drop dyschromia, nail plate crumbling, and pitting and will be scored (0 for “no” 
or 1 for “yes”) for leukonychia, nail bed hyperkeratosis, splinter hemorrhages, and red spots in 
the lunula. The score for an individual nail ranges from 0 to 13 with higher scores indicative of 
more severe nail PSO. The total mNAPSI score is the sum of the scores for each individual nail. 
If a nail is unaffected, it will be recorded as such and will not contribute to the total mNAPSI 
score. Subjects with nail PSO at Baseline are defined as those with an mNAPSI score >0 at 
Baseline. 
The mNAPSI will be assessed at the visits specified in Table 5‒1. 
9.7 
pp-IGA 
A static IGA for palmoplantar PSO will be used to assess palmoplantar disease severity. 
All subjects will complete the pp-IGA at Baseline. Only subjects with palmoplantar involvement 
at Baseline will complete the pp-IGA at the other visits specified in Table 5‒1. Subjects with 
palmoplantar involvement at Baseline are defined as those with a pp-IGA score >0 at Baseline. 
Palmoplantar disease will be assessed in terms of clinical signs of redness, thickness, and 
scaliness using a 5-point scale (Table 9‒6). 
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Table 9‒6: 
pp-IGA 
Score 
Short Descriptor 
Detailed Descriptor 
0 
Clear 
Palmoplantar areas have no signs of PSO; post-inflammatory 
hyperpigmentation may be present 
1 
Almost clear 
Palmoplantar areas have no thickening; normal to pink coloration; no to 
minimal focal scaling 
2 
Mild 
Palmoplantar areas have just detectable to mild thickening; pink to light 
red coloration; predominately fine scaling 
3 
Moderate 
Palmoplantar areas have clearly distinguishable to moderate thickening; 
dull to bright red and clearly distinguishable coloration; moderate 
scaling 
4 
Severe 
Palmoplantar areas have severe thickening with hard edges; bright to 
deep dark red coloration; severe/coarse scaling covering almost all or 
all lesions; numerous fissures 
PSO=psoriasis; pp-IGA=palmoplantar-specific Investigator’s Global Assessment 
9.8 
Euro Quality of Life 5-Dimensions, 3-Level 
The EQ-5D-3L health questionnaire provides a descriptive profile and a single index value for 
health status. The instrument is comprised of a 5-item health status measure and a VAS. The 
EQ-5D-3L VAS records the respondent’s self-rated health status on a vertical 20cm scale, 
graduated from 0 to 100 (0=worst imaginable health status, 100=best imaginable health status). 
The EQ-5D-3L will be assessed at the visits specified in Table 5‒1. 
9.9 
Short Form 36-Item Health Survey 
The SF-36 (Version 2, standard recall) is a 36-item generic health related QOL instrument that 
uses a recall period of 4 weeks. Items are grouped into 8 domains as follows: Physical 
Functioning (10 items), Role Physical (4 items), Bodily Pain (2 items), General Health (5 items), 
Vitality (4 items), Social Functioning (2 items), Role Emotional (3 items), Mental Health 
(5 items), and 1 item for perceived stability or change in health (Health Transition) during the 
last year. The concepts represented by these domains contribute to physical, mental, and social 
aspects of health-related QOL. In addition to domain scores, the PCS and MCS scores are 
calculated from the 8 domains (excluding the Health Transition item). Component scores 
appreciate the impact of each domain on physical and mental health status (Maruish, 2011). Each 
of the 8 domain scores and the component summary scores range from 0 to 100, with a higher 
score indicating a better health status. The domains and the 2 component summary scores are 
standardized with a mean of 50 and a standard deviation (SD) of 10 in the general USA 
population. The minimally important differences (MIDs), in terms of T-score points at a group 
level, for SF-36 domains and component summaries are the following: PCS, 2; MCS, 3; Physical 
Functioning, 3; Role Physical, 3; Bodily Pain, 3; General Health, 2; Vitality, 2; Social 
Functioning, 3; Role Emotional, 4; and Mental Health, 3. 
The SF-36 will be completed by the subject the visits specified in Table 5‒1. 
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9.10 
Patient Global Assessment of psoriasis 
The Patient Global Assessment of PSO is a PSO-specific item in which the patient responds to 
the multiple-choice question, “How severe are your psoriasis-related symptoms right now?” 
Possible responses to the question are “no symptoms,” “mild symptoms,” “moderate symptoms,” 
“severe symptoms,” or “very severe symptoms.” 
The Patient Global Assessment of PSO will be performed as part of the patient symptoms diary 
from Screening through the Initial Treatment Period. 
During the double-blind Maintenance Treatment Period, this assessment will be completed at the 
visits specified in Table 5‒1. 
9.11 
Patient Symptom Diary responses 
UCB developed a new patient-reported outcome (PRO) measure that will be used to assess key 
symptoms relevant to patients with moderate to severe chronic plaque PSO. PS0010 used the 
draft PRO measure in selected countries to enable psychometric validation of the PRO. Site staff 
will train the participating subjects on the use of the electronic PRO (ePRO) diary at the 
Screening Visit, following which the device will be dispensed to the subject for home use until 
the Week 24 Visit. The ePRO diary will be administered on a daily basis from Screening to the 
Week 24 Visit. 
The ePRO diary will also administer the patient global assessment of PSO as noted above 
appropriate anchor items at the end of every study week  The ePRO diary software will be 
programmed such that the subjects will be given a window of opportunity to complete the ePRO 
diary. The data collected on the ePRO diary will be uploaded to a central server database and 
will be 21 CFR Part 11 compliant. Appropriate GCP procedures (including subject/site training 
and testing) will be performed at the study sites. 
9.12 
sPASE questionnaire 
The PASE questionnaire is a self-administered tool to screen for active PsA in patients with PSO 
(Husni et al, 2014). The questionnaire consists of 15 items that are divided into a 7-item 
symptoms subscale and an 8-item functions subscale. Standardized responses are based on 5 
categories relating to agreement (strongly agree [5], agree [4], no idea [3], disagree [2], and 
strongly disagree [1]). The total maximum score is 75 points (symptom score: 35 points and 
function score: 40 points). Psoriatic Arthritis Screening and Evaluation questionnaire scores 
≥47 points are indicative of active PsA. 
If a subject with a PASE score ≥47 points is referred to a rheumatologist, the referral will be 
recorded in the eCRF. Subjects with PsA, defined as a past medical history of PsA or PASE ≥47, 
are required to receive the additional PsA assessments as noted in Section 9.13. 
The PASE questionnaire will be completed at the visits in Table 5‒1. 
9.13 
PGADA for the arthritis visual analog scale 
The PGADA for the arthritis VAS will be used to provide an overall evaluation of arthritis 
disease symptoms. Subjects will respond to the question, “Considering all the ways your arthritis 
affects you, please mark a vertical line on the scale below to show how you are feeling today,” 
using a VAS where 0 is “very good, no symptoms” and 100 is “very poor, severe symptoms.” 
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All subjects will complete the PGADA at Baseline. Subjects with PsA at Baseline (defined as a 
past medical history of PsA or PASE ≥47) will complete the PGADA at the visits specified in 
Table 5‒1. 
9.14 
WPAI-SHP V2.0 
The WPAI-SHP V2.0 is a patient-reported questionnaire that assesses subject’s employment 
status, work absenteeism, work impairment while working (presenteeism), overall work, and 
daily activity impairment attributable to a specific health problem (WPAI-SHP) (Reilly et al, 
1993). It has been used in several clinical studies of biologic therapy in subjects with plaque PSO 
(Kimball et al, 2012; Vender et al, 2012). 
Five out of 6 items of the WPAI-SHP are regrouped into the 4 dimensions, with scores expressed 
as percentage, where higher numbers indicate greater impairment and less productivity, ie, worse 
outcomes, as described in the WPAI-SHP scoring rules. 
The WPAI-SHP V2.0 will be assessed at the visits specified in Table 5‒1. 
10 
ASSESSMENT OF PHARMACOKINETIC AND 
PHARMACOGENOMIC VARIABLE(S) 
10.1 
Pharmacokinetic variables 
Blood samples for measurement of PK assessments (Section 4.3.3) will be collected at the time 
points specified in the schedule of study assessments (Table 5‒1). 
At dosing visits, blood samples will be drawn prior to dosing, and will be drawn at the same time 
of the sampling for clinical laboratory tests. The time and date of collection will be recorded in 
the eCRF. 
Instructions pertaining to sample collection, processing, storage, labeling, and shipping are 
provided in the laboratory manual for this study. Detailed information on sample analysis will be 
provided in a bioanalytical report. 
Pharmacokinetic samples from subjects receiving adalimumab will not be analyzed, but stored 
for potential future PK analysis and anti-drug antibody determination. 
10.2 
Pharmacogenomic variables 
A separate ICF will be required for those subjects who agree to participate in the genomics, 
genetics, and proteomics substudy, and must be signed prior to collection of any samples for the 
substudy. The substudy will only be conducted where ethically accepted and authorized by the 
regulatory agencies. Refusal to participate in the substudy will not affect a subject’s ability to 
participate in the main study. 
These analyses will enable evaluation of biomarkers relative to disease biology and progression, 
drug treatment, and inflammatory and immune response processes. The nature and format of 
these tentative analyses will be determined at a later date. 
For individuals consenting to the genomics, genetics, and proteomics substudy, blood samples 
will be drawn for exploratory genetic/epigenetic, genomic, proteomic, and metabolomics 
analysis and for candidate exploratory biomarker analyses. Candidate exploratory biomarker 
evaluations may include, but are not limited to, IL-17A/IL-17F pathway signaling and PSO 
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biology (eg, IL-17A, IL-17F, IL-23, IL-6, tumor necrosis factor, dendritic cell-specific 
transmembrane protein, and circulating osteoclast precursors). 
Collection of these samples will occur at the time points specified in the schedule of study 
assessments (Table 5‒1). At dosing visits, blood samples will be drawn prior to dosing, and will 
be drawn at the same time of the sampling for clinical laboratory tests. The time and date of 
collection will be recorded in the eCRF. The samples will be stored at -80°C at the central 
biorepository for up to 20 years. 
Instructions pertaining to sample collection, processing, storage, labeling, and shipping are 
provided in the laboratory manual for this study. Detailed information on sample analysis will be 
provided in a bioanalytical report. 
11 
ASSESSMENT OF IMMUNOLOGICAL VARIABLE(S) 
Blood samples for measurement of antibodies to bimekizumab will be collected at the visits 
specified in Table 5‒1. The threshold for antibody positivity will be defined prior to analysis. 
At dosing visits, blood samples will be drawn prior to dosing, and will be drawn at the same time 
of the sampling for clinical laboratory tests. The time and date of collection will be recorded in 
the eCRF. 
Instructions pertaining to sample collection, processing, storage, labeling, and shipping are 
provided in the laboratory manual for this study. The presence of antibodies to bimekizumab will 
be determined using a validated bioanalytical method. Detailed information on sample analysis 
will be provided in a bioanalytical report. 
12 
ASSESSMENT OF SAFETY 
12.1 
Adverse events 
12.1.1 
Definitions 
12.1.1.1 
Adverse event 
An AE is any untoward medical occurrence in a patient or clinical investigation subject 
administered a pharmaceutical product that does not necessarily have a causal relationship with 
this treatment. An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease temporally associated with the use of a 
medicinal (investigational) product, whether or not related to the medicinal (investigational) 
product. 
In order to ensure complete safety data collection, all AEs occurring during the study (ie, after 
the signing of the ICF), including any pretreatment and posttreatment periods required by the 
protocol, must be reported in the eCRF even if no IMP was taken but specific study procedures 
were conducted. This includes all AEs not present prior to the initial visit and all AEs that 
recurred or worsened after the initial visit. 
Signs or symptoms of the condition/disease for which the IMP is being studied should be 
recorded as AEs only if their nature changes considerably or their frequency or intensity 
increases in a clinically significant manner as compared to the clinical profile known to the 
Investigator from the subject’s history or the Baseline Period. 
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12.1.1.2 
Serious adverse event 
Once it is determined that a subject experienced an AE, the seriousness of the AE must be 
determined. An SAE must meet 1 or more of the following criteria: 
 Death 
 Life-threatening 
(Life-threatening does not include a reaction that might have caused death had it occurred in 
a more severe form.) 
 Significant or persistent disability/incapacity 
 Congenital anomaly/birth defect (including that occurring in a fetus) 
 Important medical event that, based upon appropriate medical judgment, may jeopardize the 
patient or subject and may require medical or surgical intervention to prevent 1 of the other 
outcomes listed in the definition of serious 
(Important medical events may include, but are not limited to, potential Hy’s Law [see 
Section 12.1.1.3], allergic bronchospasm requiring intensive treatment in an emergency room 
or at home, blood dyscrasias that do not result in inpatient hospitalization, or the 
development of drug dependency or drug abuse.) 
 Initial inpatient hospitalization or prolongation of hospitalization 
(A patient admitted to a hospital, even if he/she is released on the same day, meets the 
criteria for the initial inpatient hospitalization. An emergency room visit that results in 
admission to the hospital would also qualify for the initial inpatient hospitalization criteria. 
However, emergency room visits that do not result in admission to the hospital would not 
qualify for this criteria and, instead, should be evaluated for 1 of the other criteria in the 
definition of serious [eg, life-threatening adverse experience, important medical event]. 
Hospitalizations for reasons not associated with the occurrence of an AE [eg, preplanned 
surgery or elective surgery for a pre-existing condition that has not worsened or manifested 
in an unusual or uncharacteristic manner] do not qualify for reporting. For example, if a 
subject has a condition recorded on his/her medical history and later has a preplanned surgery 
for this condition, it is not appropriate to record the surgery or hospitalization as an SAE, 
since there is no AE upon which to assess the serious criteria. Please note that, if the 
pre-existing condition has worsened or manifested in an unusual or uncharacteristic manner, 
this would then qualify as an AE and, if necessary, the seriousness of the event would need to 
be determined.) 
Confirmed active TB must be reported as an SAE. The Investigator is to complete and submit the 
TB Follow-Up Form provided. 
12.1.1.2.1 
Anticipated serious adverse events 
The following Anticipated SAEs are anticipated to occur in the population studied in this 
protocol at some frequency that is independent of drug exposure. 
This list does not change the Investigator’s obligation to report all SAEs (including Anticipated 
SAEs) as detailed in Section 12.1.2.3. 
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Table 12.1: Anticipated serious adverse events for the population of subjects 
with moderate to severe chronic plaque psoriasis 
MedDRA® system order class 
MedDRA preferred term 
Skin and subcutaneous tissue disorders 
Any psoriatic condition HLT 
Musculoskeletal and connective tissue disorders 
Psoriatic arthropathy 
HLT=High Level Term; MedDRA=Medical Dictionary for Regulatory Activities; SAE=serious adverse event 
Note: Exception: Listed events will not be regarded as anticipated SAEs if they are life threatening or if they result 
in the death of the study subject. 
12.1.1.3 
Adverse events of special interest 
An AE of special interest (AESI) is any AE that a regulatory authority has mandated be reported 
on an expedited basis, regardless of the seriousness, expectedness, or relatedness of the AE to the 
administration of a UCB product/compound. 
Potential Hy’s Law, defined as ≥3xULN ALT or AST with coexisting ≥2xULN total bilirubin in 
the absence of ≥2xULN ALP, with no alternative explanation for the biochemical abnormality, 
must ALWAYS be reported to UCB as an AESI (ie, without waiting for any additional etiologic 
investigations to have been concluded). Follow-up information should then be reported if an 
alternative etiology is identified during investigation and monitoring of the subject. 
12.1.1.4 
Other safety topics of interest 
Pre-specified safety topics of interest for the study are: infections (serious, opportunistic, fungal, 
and TB), neutropenia, hypersensitivity, suicidal ideation and behavior, depression, major 
cardiovascular events, liver function test changes/enzyme elevations, malignancies, and 
inflammatory bowel diseases (with gastroenterology referral, as appropriate). This is based on 
findings from the IMP clinical program to date, potential risks generally associated with biologic 
immunomodulators, or findings from other medicines with a related mechanism of action. There 
are no specific AE reporting requirements for these topics, however special monitoring, 
additional data collection activities, and/or enhanced signal detection activities (within UCB) are 
in place. 
12.1.2 
Procedures for reporting and recording adverse events 
The subject will be given the opportunity to report AEs spontaneously. A general prompt will 
also be given at each study visit to detect AEs. For example: 
“Did you notice anything unusual about your health (since your last visit)?” 
In addition, the Investigator should review any self-assessment procedures (eg, diary cards) 
employed in the study. 
12.1.2.1 
Description of adverse events 
When recording an AE, the Investigator should use the overall diagnosis or syndrome using 
standard medical terminology, rather than recording individual symptoms or signs. The eCRF 
and source documents should be consistent. Any discrepancies between the subject’s own words 
on his/her own records (eg, diary card) and the corresponding medical terminology should be 
clarified in the source documentation. 
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When recording the severity of an AE in the eCRF (ie, mild, moderate, or severe), the 
Investigator may refer to the Common Terminology Criteria for Adverse Events (CTCAE) 
Version 4.0 (http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm) for 
additional guidance as needed. Details for completion of the Adverse Event eCRF (including 
judgment of relationship to IMP) are described in the eCRF Completion Guidelines. 
12.1.2.2 
Rule for repetition of an adverse event 
An increase in the intensity of an AE should lead to the repetition of the AE being reported with: 
 The outcome date of the first AE that is not related to the natural course of the disease being 
the same as the start date of the repeated AE, and the outcome of “worsening” 
 The AE verbatim term being the same for the first and repeated AE, so that the repeated AE 
can be easily identified as the worsening of the first one 
12.1.2.3 
Additional procedures for reporting serious adverse events 
If an SAE is reported, UCB must be informed within 24 hours of receipt of this information by 
the site (see contact information for SAE reporting listed in the Serious Adverse Event Reporting 
section at the front of the protocol). The Investigator must forward to UCB (or its representative) 
a duly completed “Investigator SAE Report Form for Development Drug” (SAE report form) 
provided by UCB, even if the data are incomplete, or if it is obvious that more data will be 
needed in order to draw any conclusions. Information recorded on this form will be entered into 
the global safety database. 
An Investigator SAE Report Form will be provided to the Investigator. The Investigator SAE 
Report Form must be completed in English. 
It is important for the Investigator, when completing the SAE Report Form, to include the 
assessment as to a causal relationship between the SAE and the IMP administration. This insight 
from the Investigator is very important for UCB to consider in assessing the safety of the IMP 
and in determining whether the SAE requires reporting to the regulatory authorities in an 
expedited manner. 
Additional information (eg, autopsy or laboratory reports) received by the Investigator must be 
provided within 24 hours. All documents in the local language must be accompanied by a 
translation in English, or the relevant information included in the same document must be 
summarized in the Investigator SAE Report Form. 
The Investigator is specifically requested to collect and report to UCB (or its representative) any 
SAEs (even if the Investigator is certain that they are in no way associated with the IMP), up to 
30 days from the end of the study for each subject, and to also inform participating subjects of 
the need to inform the Investigator of any SAE within this period. Serious AEs that the 
Investigator thinks may be associated with the IMP must be reported to UCB regardless of the 
time between the event and the end of the study. 
Upon receipt of the SAE Report Form, UCB will perform an assessment of expectedness of the 
reported SAE. The assessment of the expectedness of the SAE is based on the IB. 
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12.1.3 
Follow up of adverse events 
An AE should be followed until it has resolved, has a stable sequelae, the Investigator 
determines that it is no longer clinically significant, or the subject is lost to follow up. This 
follow-up requirement applies to AEs, SAEs, and AESIs; further details regarding follow up of 
PDILI events is provided in Section 12.2.1.4. 
If an AE is ongoing at the end of the study for a subject, follow up should be provided until 
resolution/stable level of sequelae is achieved, or until the Investigator no longer deems that it is 
clinically significant, or until the subject is lost to follow up. If no follow up is provided, the 
Investigator must provide a justification. The follow up will usually be continued for 20 weeks 
after the subject has discontinued his/her IMP. 
Information on SAEs obtained after clinical database lock will be captured through the Patient 
Safety (PS) database without limitation of time. 
12.1.4 
Pregnancy 
If an Investigator is notified that a subject has become pregnant after the first intake of any IMP, 
the Investigator must immediately notify UCB’s PS department by providing the completed 
Pregnancy Report and Outcome Form (for contact details see Serious Adverse Event reporting 
information at the beginning of this protocol). The subject should be withdrawn from the study 
as soon as pregnancy is known (by positive pregnancy test), and the following should be 
completed: 
 The subject should return for an early discontinuation visit. 
 The subject should immediately stop the intake of the IMP. 
 A SFU Visit should be scheduled 20 weeks after the subject has discontinued her IMP. 
The Investigator must inform the subject of information currently known about potential risks 
and about available treatment alternatives. 
The pregnancy will be documented on the Pregnancy Report and Outcome Form provided to the 
Investigator. The progression of the pregnancy and the eventual birth (if applicable) must be 
followed up using the Pregnancy Report and Outcome Form in which the Investigator has to 
report on the health of the mother and of the child. Every reasonable attempt should be made to 
follow the health of the child for 30 days after birth for any significant medical issues. In certain 
circumstances, UCB may request that follow up is continued for a period longer than 30 days. If 
the subject is lost to follow up and/or refuses to give information, written documentation of 
attempts to contact the subject needs to be provided by the Investigator and filed at the site. 
UCB’s PS department is the primary contact for any questions related to the data collection for 
the pregnancy, eventual birth, and follow up. 
In cases where the partner of a male subject enrolled in a clinical study becomes pregnant, the 
Investigator or designee is asked to contact the subject to request consent of the partner via the 
Partner Pregnancy Consent form that has been approved by the responsible IRB/IEC and should 
be available in the Investigator site file. In case of questions about the consent process, the 
Investigator may contact the UCB/contract research organization (CRO) contract monitor for the 
study. The Investigator will complete the Pregnancy Report and Outcome form and send it to 
UCB’s PS department (for contact details see Serious Adverse Event reporting information at the 
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beginning of this protocol) only after the partner has agreed that additional information can be 
captured and has provided the signed Partner Pregnancy Consent form. UCB’s PS department is 
also the primary contact for any questions related to the data collection for the partner pregnancy, 
eventual birth, and follow-up. 
A pregnancy becomes an SAE in the following circumstances: miscarriage, elective abortion 
when medically indicated (e.g. when pregnancy is endangering life or health of woman or when 
fetus will be born with severe abnormalities), unintended pregnancy after hormonal 
contraceptive failure (if the hormonal contraceptive was correctly used), ectopic pregnancy, fetal 
demise, or any congenital anomaly/birth defect of the baby. Those SAEs must be additionally 
reported using the Investigator SAE Report Form. 
Should a subject become pregnant while participating in the study, the subject may be offered the 
option to enroll in a separate observational pregnancy follow-up study sponsored by UCB and 
conducted independently from study PS0008. If the study is available locally, the PS0008 
Investigator will be provided with locally approved information about the observational 
pregnancy follow-up study to inform the subject at the time the pregnancy is reported. 
Participation in this separate study will be voluntary and will not impact the therapeutic 
management of the subject nor interfere with termination and follow-up procedures as described 
in protocol PS0008. 
12.1.5 
Suspected transmission of an infectious agent via a medicinal 
product 
For the purposes of reporting, any suspected transmission of an infectious agent via a medicinal 
product should be considered as an SAE; such cases must be reported immediately, recorded in 
the AE module of the eCRF, and followed as any other SAE. Any organism, virus, or infectious 
particle (eg, prion protein transmitting transmissible spongiform encephalopathy), pathogenic or 
nonpathogenic, is considered an infectious agent. 
12.1.6 
Overdose of investigational medicinal product 
Excessive dosing (beyond that prescribed in the protocol and including overdose) should be 
recorded in the eCRF. Any SAE or nonserious AE associated with excessive dosing must be 
followed as any other SAE or nonserious AE. These events are only considered AEs or SAEs if 
there are associated clinical signs and symptoms or if the act of taking the excess medicine itself 
is an AE or SAE (eg, suicide attempt). 
12.1.7 
Safety signal detection 
Selected data from this study will be reviewed periodically to detect as early as possible any 
safety concern(s) related to the IMP so that Investigators, clinical study subjects, regulatory 
authorities, and IRBs/IECs will be informed appropriately and as early as possible. 
In addition, an independent Data Monitoring Committee (DMC) will periodically review and 
monitor safety data from this study and advise UCB. Details are provided in the DMC Charter. 
Cardiovascular and Neuropsychiatric Adjudication Committees will also periodically review and 
monitor safety data from this study and advise UCB. Details are provided in the Adjudication 
Committee Charters. 
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The Study Physician or medically qualified designee/equivalent will conduct an ongoing review 
of SAEs and perform ongoing SAE reconciliations in collaboration with the PS representative. 
As appropriate for the stage of development and accumulated experience with the IMP, 
medically qualified personnel at UCB may identify additional safety measures (eg, AEs, vital 
signs, laboratory or ECG results) for which data will be periodically reviewed during the course 
of the study. 
12.2 
Laboratory measurements 
Clinical laboratory assessments consist of serum chemistry, hematology, urinalysis, and urine 
drug screen. A centralized laboratory will be used to supply all laboratory test supplies and 
analyze all blood and urine samples for hematology, biochemistry, and urinalysis measurements. 
Any unscheduled laboratory testing should also be collected using the central laboratory. Testing 
to rule out hepatitis B, hepatitis C, and HIV (see Exclusion Criterion #9, Section 6.2) will be 
performed at Screening in addition to those measurements listed in Table 12‒2. 
Specific details regarding the handling and processing of serum chemistry, hematology, and 
urinalysis samples are provided in the study laboratory manuals. 
The following laboratory parameters will be measured: 
Table 12‒2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
Basophils  
Calcium  
pH 
Eosinophils  
Chloride  
Albumin (protein) 
Lymphocytes  
Magnesium 
Glucose 
Monocytes  
Potassium  
Blood 
Neutrophils  
Sodium  
Leukocyte esterase 
Hematocrit  
Glucose  
Nitrite 
Hemoglobin  
BUN  
Urine dipstick for pregnancy testingb 
MCH 
Creatinine 
Urine drug screenc 
MCHC 
ALP 
 
MCV 
AST 
 
Platelet count 
ALT 
 
RBC count 
GGT 
 
WBC count 
Total bilirubin 
 
 
Serum pregnancy testinga 
 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea 
nitrogen; GGT=gamma-glutamyltransferase; MCH=mean corpuscular hemoglobin; MCHC=mean 
corpuscular hemoglobin concentration; MCV=mean corpuscular volume; PEOT=Premature End of 
Treatment; RBC=red blood cell; SFU=Safety Follow-Up; WBC=white blood cell 
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a A urine microscopic examination will be performed if the result for albumin (protein), leukocyte esterase, blood, 
or nitrite is abnormal. A urine microscopic examination will include: WBC, RBC, epithelial cells (squamous, 
transitional, and renal tubular), hyaline casts, WBC casts, RBC casts, waxy casts, granular casts, calcium oxalate 
crystals, uric acid crystals, triphosphate crystals, yeast, bacteria, amorphous urates, and amorphous phosphates. 
b Pregnancy testing will consist of serum testing at the Screening Visit. The pregnancy test will be urine at all other 
visits. 
c Urine drug screen will be performed at Screening Visit, and Week 56 or PEOT Visit. 
12.2.1 
Evaluation of PDILI 
The PDILI IMP discontinuation criteria for this study are provided in Section 6.3.1, with the 
accompanying required follow-up investigation and monitoring detailed below. All PDILI events 
must be reported as an AE and reported to the study site and Sponsor within 24 hours of learning 
of their occurrence. Any PDILI event that meets the criterion for potential Hy’s Law must be 
reported as an AESI (see Section 12.1.1.3), and, if applicable, also reported as an SAE (see 
Section 12.1.1.2). 
Evaluation of PDILI consists of the diagnostic testing and continued monitoring included in 
Table 12‒3 (specific tests dependent on laboratory results and corresponding symptoms) and 
consultation with a local hepatologist (if applicable; discussed in Section 12.2.1.1). The local 
hepatologist is the expert usually consulted by the treating physician for assessment and 
management of potential hepatic disease. This would usually be a hepatologist, but may be a 
gastroenterologist. Additional investigation and monitoring may be required and adapted based 
on the diagnosis after the cause of the liver injury/abnormality is confirmed (details in 
Section 12.2.1.4). 
The results of all monitoring, including laboratory testing and other testing, should be made 
available to the study site and Sponsor. 
All initial tests resulting in abnormal hepatic laboratory values need to be repeated, but 
appropriate medical action must not be delayed waiting for the repeat result. 
If tests are done locally for more rapid results, a concurrent sample should also be sent to the 
central laboratory whenever possible. Medical care decisions are to be made initially using the 
most rapidly available results and a conservative approach must be taken if the results from the 
2 laboratory tests are significantly different. Data from the local and central laboratory are to be 
recorded on the applicable eCRF pages. 
When IMP is discontinued, all concomitant medications and herbal supplements that are not 
medically necessary should also be discontinued. In these cases, the Investigator should also 
consider dose reduction for medically necessary concomitant medication and consider changing 
any medically required concomitant medication known to be hepatotoxic to a suitable 
alternative  
When IMP is stopped due to PDILI (as described in Section 6.3.1), IMP must be permanently 
discontinued unless a subsequent alternative diagnosis fully explains the hepatic findings. If a 
subsequent alternative diagnosis fully explains the hepatic findings, and the requirements 
provided in Section 12.2.1.2.1 are met, rechallenge with IMP may be appropriate. 
Table 12‒3 summarizes the approach to investigate PDILI.
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Table 12‒3: Required investigations and follow-up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or 
AST 
Total 
bilirubin 
Symptoms
a of 
hepatitis of 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
≥3xULN 
≥2xULN
b NA 
Hepatology consult
c 
Medical Monitor must 
be notified within 
24 hours (eg, by 
laboratory alert) and 
subject discussed with 
Medical Monitor 
ASAP. 
Immediate, 
permanent IMP 
discontinuation. 
 
 
 
Essential: Must have 
repeat liver 
chemistry values 
and additional 
testing completed 
ASAP (see 
Section 12.2.1.3); 
recommended to 
occur at the site with 
HCP. 
Monitoring of liver 
chemistry values at least 
twice per week until 
values normalize, 
stabilize, or return to 
within baseline values.d 
≥3xULN 
NA 
Yes 
≥8xULN 
NA 
NA 
Need for hepatology 
consult to be discussed 
(required if ALT or 
AST ≥8xULN). 
Medical Monitor must 
be notified within 
24 hours (eg, by 
laboratory alert) and 
subject discussed with 
Medical Monitor 
ASAP  
Immediate, 
permanent IMP 
discontinuation. 
 
 
 
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Table 12‒3: Required investigations and follow-up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or 
AST 
Total 
bilirubin 
Symptoms
a of 
hepatitis of 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
≥5xULN 
(and ≥2x 
baseline) 
and 
<8xULN  
<2xULN 
No 
Discussion with 
Medical Monitor 
required. 
Consider need for 
hepatology consult if 
there is no evidence of 
resolution (see Follow 
up requirements).c 
Further investigation 
– immediate IMP 
discontinuation not 
required (see 
Section 12.2.1.2). 
 
IMP discontinuation 
required if any of the 
following occur: 
 Subject cannot 
comply with 
monitoring 
schedule. 
 Liver chemistry 
values continue to 
increase. 
 Liver chemistry 
values remain 
≥5xULN (and 
≥2x baseline) after 
4 weeks of 
monitoring without 
evidence of 
resolution. 
Essential: Every 
attempt must be 
made to have repeat 
liver chemistry 
values and 
additional testing 
completed within 
48 hours at the site 
with HCP (see 
Section 12.2.1.3). 
Monitoring of liver 
chemistry values at least 
twice per week for 2 
weeks.d 
 
Immediate IMP 
discontinuation 
required if liver 
chemistry values 
continue to increase. 
After 2 weeks of 
monitoring liver 
chemistry values: 
 
ALT or AST remains 
≥5xULN <8xULN, 
IMP should be 
temporarily withheld 
and subject should 
undergo repeat test in 
2 weeks. 
 
Continue IMP if ALT 
or AST values 
<5xULN; continue to 
monitor at least twice 
per week until values 
normalize, stabilize, 
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Table 12‒3: Required investigations and follow-up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or 
AST 
Total 
bilirubin 
Symptoms
a of 
hepatitis of 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
or return to within 
baseline values. 
 
If ALT or AST 
remains ≥5xULN 
after second re-test, 
immediate, 
permanent IMP 
discontinuation 
required. 
Continue to monitor until 
values normalize, 
stabilize, or return to 
within baseline values.d 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; ASAP=as soon as possible; AST=aspartate aminotransferase; HCP=healthcare practitioner; 
IMP=investigational medicinal product; NA=not applicable; PDILI=potential drug-induced liver injury; ULN=upper limit of normal 
a Hepatitis symptoms include fatigue, nausea, vomiting, and right upper quadrant pain or tenderness; hypersensitivity symptoms include eosinophilia (>5%), 
rash, and fever (without clear alternative cause). 
b If the subject also has ≥2xULN ALP, the possibility of an indication of biliary obstruction should be discussed with the Medical Monitor. 
c Details provided in Section 12.2.1.1. The local hepatologist is the expert usually consulted by the treating physician for assessment and management of 
potential hepatic disease. This would usually be a hepatologist, but may be a gastroenterologist. 
d Unless an alternative monitoring schedule is agreed by the Investigator and UCB responsible physician. Determination of stabilization is at the discretion of the 
Investigator in consultation with the hepatologist (as applicable) and UCB responsible physician, as needed. 
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12.2.1.1 
Consultation with Medical Monitor and local hepatologist 
Potential drug-induced liver injury events require notification of the Medical Monitor within 
24 hours (eg, by laboratory alert), and the subject must be discussed with the Medical Monitor as 
soon as possible. If required, the subject must also be discussed with the local hepatologist. The 
local hepatologist is the expert usually consulted by the treating physician for assessment and 
management of potential hepatic disease. This would usually be a hepatologist, but may be a 
gastroenterologist. If determined necessary, this discussion should be followed by a full 
hepatology assessment (see Section 12.2.1.3) and SAE report (if applicable). 
12.2.1.2 
Immediate action: determination of IMP discontinuation 
All PDILI events require immediate action, testing, and monitoring. 
The immediate action is dependent on the laboratory values and symptoms of hepatitis or 
hypersensitivity and ranges from continuation of IMP (followed by immediate investigation) to 
immediate and permanent discontinuation (see Section 6.3.1 and Table 12‒3 for details). 
When IMP is discontinued, all concomitant medications and herbal supplements that are not 
medically necessary should also be discontinued. The Investigator should also consider dose 
reduction for medically necessary concomitant medication and consider changing any medically 
required concomitant medication known to be hepatotoxic to a suitable alternative. 
12.2.1.2.1 
IMP restart/rechallenge 
Rechallenge with IMP can occur only if ALL of the following requirements are met: 
 The results of additional testing and monitoring described in Section 12.2.1.3 and 
Section 12.2.1.4 confirm a nondrug-related cause for the abnormal hepatic laboratory 
parameters and any associated symptoms (ie, a subsequent alternative diagnosis fully 
explains the hepatic findings).  
 The subject has shown clear therapeutic benefit from the IMP. 
 Subject’s ALT or AST elevations do not exceed ≥5xULN. 
 Subject’s total bilirubin is <2xULN. 
 Subject has no signs or symptoms of hypersensitivity or hepatitis.  
 The rechallenge is approved by the UCB responsible physician, DMC, and a hepatologist. 
The hepatologist must be external to UCB but may be a member of the DMC. It is 
recommended that the hepatologist be a local hepatology expert or the hepatologist treating 
the subject. 
 Subject agrees to the Investigator-recommended monitoring plan. 
12.2.1.3 
Testing: identification/exclusion of alternative etiology 
The measurements and additional information required for the assessment of PDILI events when 
there is a reasonable possibility that they may have been caused by the IMP are detailed in 
Table 12‒4 (laboratory measurements) and Table 12‒5 (additional information). Results of the 
laboratory measurements and information collected are to be submitted to the Sponsor on the 
corresponding eCRF. If the medical history of the subject indicates a requirement for other 
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assessments not included below, these additional assessments should be completed and 
submitted, as applicable. 
All blood samples should be stored, if possible. If tests are done locally for more rapid results, a 
concurrent sample must also be sent to the central laboratory. 
The following measurements are to be assessed:  
Table 12‒4: PDILI laboratory measurements 
Virology-related 
Hepatitis A IgM antibody 
HBsAg 
Hepatitis E IgM antibody 
HBcAb-IgM 
Hepatitis C RNA 
Cytomegalovirus IgM antibody 
Epstein-Barr viral capsid antigen IgM antibody (if unavailable, obtain 
heterophile antibody or monospot testing) 
Immunology 
Anti-nuclear antibody (qualitative and quantitative) 
Anti-smooth muscle antibody (qualitative and quantitative) 
Type 1 anti-liver kidney microsomal antibodies (qualitative and quantitative) 
Hematology 
Eosinophil count 
Urinalysis 
Urine drug screena 
Chemistry 
Amylase 
Sodium, potassium, chloride, glucose, BUN, creatinine 
Total bilirubin, ALP, AST, ALT, GGT, total cholesterol, albumin 
If total bilirubin ≥1.5xULN, obtain fractionated bilirubin to obtain % direct 
bilirubin 
Serum CPK and LDH to evaluate possible muscle injury causing transaminase 
elevation 
Additional 
Prothrombin time/INRb 
Serum pregnancy testc 
PK  
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea 
nitrogen; CPK=creatine phosphokinase; GGT=gamma glutamyl transferase; HBcAb-IgM=hepatitis B core 
antibody-IgM; HBsAg=hepatitis B surface antigen; IgM=immunoglobulin M; INR=international normalized ratio; 
LDH=lactate dehydrogenase; PDILI=potential drug-induced liver injury; PK=pharmacokinetic; RNA=ribonucleic 
acid; ULN=upper limit of normal 
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Table 12‒4: PDILI laboratory measurements 
a Tests in addition to the specified analytes may be performed based on the Investigator’s medical judgment and 
subject history. 
b Measured only for subjects with ALT >8xULN, elevations in total bilirubin, and symptoms of hepatitis or 
hypersensitivity. Hepatitis symptoms include fatigue, nausea, vomiting, and right upper quadrant pain or 
tenderness; hypersensitivity symptoms include eosinophilia (>5%), rash, and fever (without clear alternative 
cause). 
c For women of childbearing potential. 
 
The following additional information is to be collected: 
Table 12‒5: PDILI information to be collected 
New or updated information 
Concomitant prescription and over-the-counter medications (eg, acetaminophen, herbal remedies, 
vitamins); dosages and dates should be included. 
Pertinent medical history, including the following: 
 
History of liver disease (eg, autoimmune hepatitis, nonalcoholic steatohepatitis or other “fatty 
liver disease”) 
 
Adverse reactions to drugs 
 
Allergies 
 
Relevant family history or inheritable disorders (eg, Gilbert’s syndrome, alpha-1 antitrypsin 
deficiency) 
 
Recent travel 
Progression of malignancy involving the liver (Note: Metastatic disease to the liver, by itself, should not 
be used as an explanation for significant AST and/or ALT elevations.) 
The appearance or worsening of clinical symptoms of hepatitis or hypersensitivity (eg, fatigue, nausea, 
vomiting, right upper quadrant pain or tenderness, decreased appetite, abdominal pain, jaundice, fever, or 
rash) 
Recent clinically significant hypotension or hypoxemia with compromised cardiopulmonary function 
Alcohol and illicit drug use 
Results of liver imaging or liver biopsy, if done 
Results of any specialist or hepatology consult, if done 
Any postmortem/pathology reports 
ALT=alanine aminotransferase; AST=aspartate aminotransferase; PDILI=potential drug-induced liver injury 
12.2.1.4 
Follow-up evaluation 
Potential drug-induced liver injury events require follow-up monitoring as described in 
Table 12‒3. Monitoring should continue until liver chemistry values normalize, stabilize, or 
return to Baseline. Determination of stabilization is at the discretion of the Investigator in 
consultation with the hepatologist (as applicable) and UCB responsible physician, as needed. 
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12.3 
Other safety measurements 
12.3.1 
Assessment and management of TB and TB risk factors 
All subjects will be assessed for TB at Screening and at the time points specified in the Schedule 
of Assessments (Table 5‒1) through physical examination for signs and symptoms of TB, chest 
x-ray (Section 12.3.1.2), laboratory testing (Section 12.3.1.1), and subject questionnaire 
(Section 12.3.1.3). 
At Screening, all subjects will have an IGRA test (QuantiFERON TB test is recommended), a 
chest x-ray (unless already performed within 3 months of Screening) and examination for signs 
and symptoms of TB. In addition, each subject will complete a TB questionnaire directed at 
potential exposure and symptoms of TB. 
For the purposes of this study, TB definitions are as follows: 
a. Known TB infection: 
 Active TB infection or clinical signs and symptoms suspicious for TB (pulmonary or 
extra-pulmonary). 
 History of active TB infection involving any organ system or findings in other organ 
systems consistent with TB infection, unless adequately treated and proven to be fully 
recovered upon consult with a TB specialist. 
 Any evidence by radiography or other imaging modalities consistent with previously 
active TB infection that is not reported in the subject’s medical history. 
b. High risk of acquiring TB infection: 
 Known close exposure to another person with active TB infection within the 3 months 
prior to Screening. 
 Time spent in a healthcare delivery setting or institution where individuals infected with 
TB are housed and where the risk of transmission of infection is high. 
c. Latent TB infection (unless appropriate prophylaxis is initiated at least 8 weeks prior to IMP 
dosing and continued to completion of prophylaxis): 
 The absence of signs, symptoms, or physical findings suggestive of TB infection with a 
positive IGRA test (or 2 indeterminate IGRA test results) and a chest x-ray (or other 
imaging) without evidence of TB infection. If the result of the IGRA test is 
indeterminate, the particular IGRA test previously performed may be repeated once; if 
positive or indeterminate on retest, the subject may not be randomized to IMP without 
further evaluation by a TB specialist and discussion with the Study Physician, if LTB 
infection is identified. The retest must be done during the protocol-defined Screening 
window. 
Note: If available, respiratory or other specimens must also be smear and culture negative for 
TB (CDC diagnosis of LTB infection) http://www.cdc.gov/TB/topic /testing/default.htm). 
d. NTMB infection is defined as a clinical infection caused by mycobacterial species other than 
those belonging to the Mycobacterium tuberculosis complex. 
e. Tuberculosis test conversion: 
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 A positive IGRA result for the current test when previous IGRA test results were 
negative. All subjects with TB test conversion must immediately stop IMP administration 
and be referred to a TB specialist for further evaluation. Confirmed TB test conversions 
should be classified as due to LTBI, active TB infection, or NTMB, and reported to the 
UCB PS function. 
Subject eligibility, retesting requirements, and treatment requirements are depicted in 
Figure 12-1. 
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12.3.1.1 
Tuberculosis assessment by IGRA 
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB test is 
recommended) will be performed as described in Table 5‒1 for all subjects. The test results will 
be reported as positive, negative, or indeterminate. Positive and indeterminate TB test results 
must be reported as an AE and appropriately updated once the final diagnosis is known (e.g. 
active TB, latent TB, or false positive TB test). UCB also recommends that a TB specialist be 
consulted where TB (latent or active) is suspected or if there are doubts regarding test results. If 
latent or active TB is identified, subject must undergo appropriate study-specified withdrawal 
procedures. The retest during Screening must be done during the protocol-defined Screening 
window. 
12.3.1.2 
Chest x-ray for tuberculosis 
A plain posteroanterior chest x-ray must be performed in the Screening Period unless one has 
been performed within 3 months prior to the Screening Visit. The chest x-ray (or, if done, 
Computed Axial Tomography [CAT] of the Chest) must be clear of signs of TB infection 
(previous or current) before first IMP administration. All chest imaging (particularly x-rays) 
should be available for review by the Investigator before randomization of the subject. The chest 
x-ray reading should be repeated if the TB test was confirmed positive. If the second read of the 
pretreatment chest x-ray is confirmed to be clear, the subject may be included in the study 8 
weeks after the start of the TB prophylactic treatment. If the pretreatment chest x-ray is not 
available for a re-read, it should be repeated after notification to the radiologist that this subject 
is IGRA positive, and confirmed to be clear for signs of TB. 
The chest imaging must be negative for any old or recent TB infection as determined by a 
qualified radiologist and/or pulmonary physician. Any new clinically significant findings post 
Baseline on chest x-ray must be documented in the source documents and the eCRF as an AE. 
12.3.1.3 
Tuberculosis questionnaire 
The questionnaire “Evaluation of signs and symptoms of tuberculosis” should be used as a 
source document. The questionnaire will be completed as described in Table 5‒1. The 
questionnaire will assist with the identification of subjects who may require therapy for TB. A 
subject who answers “Yes” to the question “Has the subject been in close contact with an 
individual with active TB, or an individual who has recently been treated for TB?” at Screening 
is excluded. A “Yes” response to any of the other questions within the questionnaire at Screening 
should trigger further careful assessment to determine if subject has LTB or active TB (see 
Exclusion Criterion #12 Section 6.2). A “Yes” response to any of the questions during the study 
should trigger further assessments to determine if the subject has either LTB or active TB 
infection. 
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12.3.1.4 
Tuberculosis management 
During the study, subjects who develop evidence of LTB infection or active TB must 
immediately stop further administration of IMP and will be referred to an appropriate TB 
specialist (pulmonologist or infectious disease specialist) for further evaluation. Evidence of 
LTB infection is defined as subject’s IGRA test converts to positive or indeterminate (and 
confirmed indeterminate on repeat), or the subject’s questionnaire or history and physical 
indicates that TB infection or exposure may have occurred. Evidence of active TB includes, in 
addition to the aforementioned tests, signs and symptoms of organ involvement. In either 
situation, the subject should be carefully assessed by a TB specialist for active TB. Subjects 
diagnosed with active TB should be withdrawn from the study and receive appropriate TB or 
prophylaxis therapy. 
If a TB specialist excludes an active TB infection the subject can proceed with the IMP no earlier 
than 4 weeks after the start of an appropriate prophylactic therapy. 
Any presumptive diagnosis or diagnosis of a TB infection is a reportable event. Confirmed active 
TB must be reported as an SAE. The Investigator is to complete and submit the TB Follow-Up 
Form provided. 
The subject should be transferred to the care of his/her physician and managed according to the 
best available standard of care. Subjects identified as having converted to active TB during the 
study must be withdrawn and scheduled to return for the PEOT Visit as soon as possible but no 
later than the next scheduled study visit and complete all PEOT Visit assessments. 
The subject should be encouraged to complete a SFU Visit (20 weeks after the final dose of 
IMP). 
If infection with NTMB is identified during the study, the same procedure as for active TB 
acquired during the study must be followed  
12.3.2 
Pregnancy testing 
Pregnancy testing will consist of serum testing at the Screening Visit. The pregnancy test will be 
urine at all other visits. 
The Screening Visit serum pregnancy testing results must be negative and received and reviewed 
prior to randomization. A negative urine pregnancy test result should be obtained immediately 
prior to each administration of IMP at the visits specified in Table 5‒1. Pregnancy tests should 
be administered to all female subjects of childbearing potential, regardless of their use of birth 
control. 
12.3.3 
Vital signs 
Vital signs will be collected at every visit and will include systolic and diastolic BP, pulse rate, 
and body temperature (oral, axillary, or otic). Subjects should be sitting for 5 minutes before and 
during vital signs assessments. 
Vital signs are to be measured prior to blood sampling, and prior to dosing, where applicable. 
12.3.4 
12-lead electrocardiograms 
Twelve-lead standard ECGs will be recorded at the visits specified in Table 5‒1, and read by a 
central ECG reader. 
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Full details of ECG recording will be provided in the ECG Manual. 
12.3.5 
Physical examination 
A physical examination will be performed at the visits specified in Table 5‒1. The physical 
examination will include general appearance; ear, nose, and throat; eyes, hair, and skin; 
respiratory; CV; GI; musculoskeletal; hepatic; neurological (including limb reflexes); and mental 
status. All physical examinations will also include evaluation of signs and symptoms of active 
TB and risk for exposure to TB. Findings considered clinically significant changes since the 
physical examination at the Screening Visit will be recorded as AEs. 
12.3.6 
Height and body weight 
Height will be measured at Baseline only. 
Body weight will be measured at the visits specified in Table 5‒1. 
12.3.7 
Assessment of suicidal ideation and behavior 
Suicidal ideation and behavior will be assessed by using the eC-SSRS; the questionnaire will be 
self-administered by the subject and assessed by trained study personnel. This scale will be used 
to assess suicidal ideation and behavior that may occur during the study. The visits at which the 
eC-SSRS assessments will be performed are specified in the schedule of study assessments 
(Table 5‒1). 
The eC-SSRS is a standardized and validated instrument developed for the assessment of the 
severity and frequency of suicidal ideation and behavior (Posner et al, 2011; Mundt et al, 2010). 
Subjects respond to standardized clinical questions that are presented in a uniform fashion. The 
eC-SSRS defines 5 subtypes of suicidal ideation and behavior in addition to self-injurious 
behavior with no suicidal intent. The eC SSRS takes approximately 3 to 10 minutes to complete. 
Refer to Section 6.3 for eC-SSRS-related withdrawal criteria. 
12.4 
Other study measurements 
12.4.1 
Demographic information 
Demographic information will be collected in all subjects and include age, gender, race, and 
ethnicity. Information on demographics will be collected according to local rules and regulations. 
Demographic information will be recorded in the eCRF. 
12.4.2 
Medical History 
A complete medical history will be collected as part of the Screening assessment and include all 
clinically relevant past or coexisting medical conditions and surgeries. Findings will be recorded 
in the eCRF. 
12.4.3 
Psoriasis History 
A detailed history of each subject’s PSO history will be collected and include the date of onset 
and past treatments for PSO. 
12.4.4 
Data Monitoring and Adjudication Committees 
The DMC membership includes experienced clinicians and a statistician, all of whom have 
expertise in clinical trials. Cardiovascular and Neuropsychiatric Adjudication Committees will 
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also periodically review data from this trial. Both Data Monitoring and Adjudication Committee 
members may not participate in the study as principal or co-Investigators, or as study subject 
care physicians. The duration of membership for the committees will be inclusive of planned 
analyses for PS0008. Detailed role, scope, responsibilities, and complete procedures, as well as 
the identity of members, are described in the separate committee charters. 
13 
STUDY MANAGEMENT AND ADMINISTRATION 
13.1 
Adherence to protocol 
The Investigator should not deviate from the protocol. However, the Investigator should take any 
measure necessary in deviation from or not defined by the protocol in order to protect clinical 
study subjects from any immediate hazard to their health and safety. In this case, this action 
should be taken immediately, without prior notification of the regulatory authority, IRB/IEC, or 
Sponsor. 
After implementation of such measure, the Investigator must notify the CPM of the Sponsor 
within 24 hours and follow any local regulatory requirements. 
13.2 
Monitoring 
UCB (or designee) will monitor the study to meet the Sponsor’s monitoring SOPs, ICH-GCP 
guideline, and applicable regulatory requirements, and to ensure that study initiation, conduct, 
and closure are adequate. Monitoring of the study may be delegated by UCB to a CRO or a 
contract monitor. 
The Investigator and his/her staff are expected to cooperate with UCB (or designee) and to be 
available during the monitoring visits to answer questions sufficiently and to provide any 
missing information. The Investigator(s)/institution(s) will permit direct access to source 
data/documents for study-related monitoring, audits, IRB/IEC review, and regulatory 
inspection(s). 
The Investigator will allow UCB (or designee) to periodically review all CRFs and 
corresponding source documents (eg, hospital and laboratory records for each subject). 
Monitoring visits will provide UCB (or designee) with the opportunity to evaluate the progress 
of the study, verify the accuracy and completeness of CRFs, ensure that all protocol 
requirements, applicable authorities regulations, and Investigator’s obligations are being 
fulfilled, and resolve any inconsistencies in the study records. 
13.2.1 
Definition of source data 
All source documents must be accurate, clear, unambiguous, permanent, and capable of being 
audited. Source documentation should be made using some permanent form of recording (ink, 
typing, printing, optical disc). They should not be obscured by correction fluid or have temporary 
attachments (such as removable self-stick notes). Photocopies and/or print-outs of e-CRFs are 
not considered acceptable source documents. 
Source documents are original records in which raw data are first recorded. These may include 
hospital/clinic/general practitioner records, charts, diaries, x-rays, laboratory results, printouts, 
pharmacy records, care records, ECG or other printouts, completed scales, or QOL 
questionnaires, for example. Source documents should be kept in a secure, limited access area. 
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Source documents that are computer-generated and stored electronically must be printed for 
review by the monitor (eg, ECG reports). Once printed, these copies should be signed and dated 
by the Investigator and become a permanent part of the subject’s source documents. The 
Investigator will facilitate the process for enabling the monitor to compare the content of the 
printout and the data stored in the computer to ensure all data are consistent. 
Electronic data records, such as Holter monitor records or electroencephalogram records, must 
be saved and stored as instructed by UCB (or designee). 
Patient-reported outcome measures (eg, DLQI, EQ-5D-3L, SF-36, Patient Global Assessment of 
PSO, and PGADA) and ePRO diary data will be entered electronically by the subject. 
The ePRO diary data will be entered into an electronic diary by the subject. The data collection 
and database management system will be supplied by a vendor and will be compliant with the 
US Food and Drug Administration (FDA) Part 11. The data collected on the ePRO diary will be 
uploaded to a central server database and will be sent electronically to UCB (or a designated 
CRO). 
13.2.2 
Source data verification 
Source data verification ensures accuracy and credibility of the data obtained. During monitoring 
visits, reported data are reviewed with regard to being accurate, complete, and verifiable from 
source documents (eg, subject files, recordings from automated instruments, tracings [ECG], 
x-ray films, laboratory notes). All data reported on the eCRF should be supported by source 
documents, unless otherwise specified in Section 13.2.1. 
13.3 
Data handling 
13.3.1 
Case Report Form completion 
The Investigator is responsible for prompt reporting of accurate, complete, and legible data in the 
eCRFs and in all required reports. 
Any change or correction to the eCRF after saving must be accompanied by a reason for the 
change. 
Corrections made after the Investigator’s review and approval (by means of a 
password/electronic signature) will be reapproved by the Investigator. 
The Investigator should maintain a list of personnel authorized to enter data into the eCRF. 
Detailed instructions will be provided in the eCRF Completion Guidelines. 
13.3.2 
Database entry and reconciliation 
Case Report forms/external electronic data will be entered/loaded into a validated electronic 
database using a clinical data management system (CDMS). Computerized data cleaning checks 
will be used in addition to manual review to check for discrepancies and to ensure consistency of 
the data. This study is performed using Electronic Data Capture: the data are entered into the 
eCRFs once and are subsequently verified. 
An electronic audit trail system will be maintained within the CDMS to track all data changes in 
the database once the data have been saved initially into the system or electronically loaded. 
Regular backups of the electronic data will be performed. 
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13.3.3 
Subject Screening and Enrollment log/Subject Identification Code list 
The subject’s screening and enrollment will be recorded in the Subject Screening and Enrollment 
Log. 
The Investigator will keep a Subject Identification Code list. This list remains with the 
Investigator and is used for unambiguous identification of each subject. 
The subject’s consent and enrollment in the study must be recorded in the subject’s medical 
record. These data should identify the study and document the dates of the subject’s 
participation. 
13.4 
Termination of the study 
UCB reserves the right to temporarily suspend or prematurely discontinue this study either at a 
single site, multiple sites, or at all sites at any time for reasons including, but not limited to, 
safety or ethical issues, inaccurate or incomplete data recording, noncompliance, or 
unsatisfactory enrollment with respect to quality or quantity. 
If the study is prematurely terminated or suspended, UCB (or its representative) will inform the 
Investigators/institutions and the regulatory authority(ies) of the termination or suspension and 
the reason(s) for the termination or suspension, in accordance with applicable regulatory 
requirement(s). The IRB/IEC should also be informed and provided with reason(s) for the 
termination or suspension by the Sponsor or by the Investigator/institution, as specified by the 
applicable regulatory requirement(s). In addition, arrangements will be made for the return of all 
unused IMP and other material in accordance with UCB procedures for the study. 
13.5 
Archiving and data retention 
The Investigator will maintain adequate records for the study, including CRFs, medical records, 
laboratory results, Informed Consent documents, drug dispensing and disposition records, safety 
reports, information regarding participants who discontinued, and other pertinent data. 
All essential documents are to be retained by the Investigator until at least 2 years after the last 
approval of a marketing application in an ICH region and until there are no pending or 
contemplated marketing applications in an ICH region, or at least 2 years have elapsed since the 
formal discontinuation of clinical development of the IMP. These documents should be retained 
for a longer period, however, if required by the applicable regulatory requirement(s) or by an 
agreement with UCB (Committee for Proprietary Medicinal Products [CPMP]/ICH/135/95, 2002 
[Section 4.9.5]). The Investigator will contact UCB for authorization prior to the destruction of 
any study records or in the event of accidental loss or destruction of any study records. The 
Investigator will also notify UCB should he/she relocate or move the study-related files to a 
location other than that specified in the Sponsor’s trial master file. 
13.6 
Audit and inspection 
The Investigator will permit study-related audits mandated by UCB, after reasonable notice, and 
inspections by domestic or foreign regulatory authorities. 
The main purposes of an audit or inspection are to confirm that the rights and well-being of the 
subjects enrolled have been protected, that enrolled subjects (ie, signing consent and undergoing 
study procedures) are appropriate for the study, and that all data relevant for the evaluation of the 
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IMP have been processed and reported in compliance with the planned arrangements, the 
protocol, investigational site, and IRB/IEC SOPs, ICH-GCP, and applicable regulatory 
requirements. 
The Investigator will provide direct access to all study documents, source records, and source 
data. If an inspection by a regulatory authority is announced, the Investigator will immediately 
inform UCB (or designee). 
13.7 
Good Clinical Practice 
Noncompliance with the protocol, ICH-GCP, or local regulatory requirements by the 
Investigator, institution, institution staff, or designees of the Sponsor will lead to prompt action 
by UCB to secure compliance. Continued noncompliance may result in the termination of the 
site’s involvement in the study. 
14 
STATISTICS 
A description of statistical methods follows and will be described in more detail in SAP. 
14.1 
Definition of analysis sets 
The Enrolled Set (ES) will consist of all subjects who have given informed consent. 
The Randomized Set (RS) will consist of all randomized subjects. 
The Safety Set (SS) will consist of all subjects that received at least 1 dose of the IMP. 
The Bimekizumab Set (BKZ Set) will consist of all subjects who have received at least 1 dose of 
bimekizumab in this study. 
The Full Analysis Set (FAS) will consist of all randomized subjects that receive at least 1 dose of 
the IMP and have a valid measurement for each of the co-primary efficacy variables at Baseline. 
The Per-Protocol Set (PPS) will consist of all subjects in the RS who had no important protocol 
deviations affecting the primary efficacy variable. Important protocol deviations will be 
predefined and subjects with important protocol deviations will be evaluated during ongoing data 
cleaning meetings prior to unblinding of the data. 
The Pharmacokinetics Per-Protocol Set (PK-PPS) consists of all randomized subjects who 
received at least 1 dose of the IMP and provided at least 1 quantifiable plasma concentration 
postdose without important protocol deviations that would affect the concentration. 
14.2 
General statistical considerations 
Summary statistics will consist of frequency tables for categorical variables. For continuous 
variables, summary statistics will consist of the number of available observations, arithmetic 
mean, SD, median, minimum, and maximum unless stated otherwise. 
The statistical analysis of the co-primary efficacy variables and selected secondary efficacy 
variables will account for multiplicity and control the familywise Type I error rate at a 2-sided 
alpha level of 0.05 by using a fixed sequence testing procedure. 
The hypotheses (H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11 and H12) comparing bimekizumab 
vs. adalimumab will be tested at a 2-sided alpha level of 0.05. 
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The first 2 hypotheses (H1 and H2) will test whether bimekizumab is noninferior to adalimumab 
for the co-primary efficacy variables, PASI90 response at Week 16 and IGA response at 
Week 16. This evaluation of noninferiority will be tested at a 1-sided alpha level of 0.025 and 
will be based on a 1-sided 97.5% CI and a noninferiority margin of 10%. If noninferiority is 
achieved, the alpha will be passed to the next test in the sequence, allowing the testing procedure 
to proceed. The co-primary efficacy variables of PASI90 response at Week 16 and IGA response 
at Week 16 will then be evaluated for superiority relative to adalimumab at a 2-sided alpha level 
of 0.05, and testing will proceed only if superiority is achieved for both endpoints. 
The hypotheses associated with the subsequent secondary efficacy endpoints are based on testing 
for superiority relative to adalimumab. See Figure 14-1for details on this procedure. 
Figure 14-1: Sequence of testing 
 
BKZ=bimekizumab; H=hypothesis; IGA=Investigator’s Global Assessment; PASI=Psoriasis Area Severity Index; 
Q4W=every 4 weeks 
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14.3 
Planned efficacy analyses 
14.3.1 
Analysis of the primary efficacy variable 
The co-primary efficacy variables for this study will be PASI90 response and IGA response at 
Week 16, and the corresponding analyses will be based on the RS. A subject will be classified as 
a PASI90 responder if the PASI score at Week 16 has improved at least 90% from Baseline, and 
an IGA responder will be any subject with a score of 0 or 1 (Clear or Almost Clear) with at least 
a 2-category improvement from Baseline in the IGA score. The primary analysis will be based 
on a stratified Cochran-Mantel-Haenszel (CMH) test where region and prior biologic exposure 
(yes/no) will be used as stratification variables. For the assessment of noninferiority, a 
noninferiority margin of 10% will be used and evaluated based on the confidence interval for the 
stratified Cochran Mantel-Haenszel risk difference between bimekizumab and adalimumab. A 
non-inferiority margin of 10% has been selected as this is considered to be a clinically relevant 
difference that could influence the choice of interventions used to treat chronic plaque PSO. 
Therefore, a difference within the 10% non-inferiority margin would suggest a similar impact on 
efficacy between the treatments. The evaluation of superiority will use pairwise treatment 
comparisons based on the CMH test using the p-value for the general association.  
Nonresponder imputation (NRI) will be used to account for missing data in the primary analysis. 
Specifically, any subject who withdraws from study treatment prior to Week 16 or who has 
missing data for the primary efficacy variable at the Week 16 time point will be considered a 
nonresponder. Based on previous studies of biologics in subjects with moderate to severe chronic 
plaque PSO, it is expected that the number of subjects who discontinue prior to Week 16 will be 
low. For the small percentage of subjects for whom primary endpoint data are unavailable at 
Week 16, this lack of data is suggestive of an ineffective study treatment, thereby supporting the 
imputation of nonresponse. Therefore, NRI is considered an appropriate method for handling 
missing data since achieving the clinical response and making it through 16 weeks of study 
treatment are both critical components of the primary outcome. 
14.3.1.1 
Sensitivity analyses 
The primary efficacy analysis described in Section 14.3 will be repeated based on the FAS and 
the PPS. 
As a sensitivity analysis to the primary analysis method, logistic regression based on the RS will 
be used. The odds ratio of the responder rates at Week 16 will be estimated and tested between 
treatment groups using a logistic regression model with factors of treatment group, region, and 
prior biologic exposure (yes/no). The odds ratio, associated CI, and p-value based on the Wald 
test will be presented. If the logistic regression model is unable to converge, then prior biologic 
exposure may be dropped from the model to facilitate convergence. If the model is still unable to 
converge, then region may be removed from the model as well. As with the primary analysis, 
missing data will be handled using NRI. 
The center-by-treatment interaction will be tested by replacing region with center in the logistic 
regression model described above and adding a center-by-treatment interaction term. In the 
model, center will be based on the original centers prior to pooling. However, if the model is 
unable to converge due to a low number of subjects at a given center, a pooling algorithm will be 
applied in order to allow the model to converge. 
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In order to obtain reasonable estimates of variability at a given center, a minimum of 15 subjects 
will be considered acceptable for a center to be included in the model without pooling. Given the 
1:1:1 randomization allocation scheme, this should provide a minimum of about 5 subjects in the 
bimekizumab Q4W arm, 5 subjects in the bimekizumab Q4W/Q8W arm, and 5 subjects in the 
adalimumab arm. Centers with fewer than 15 subjects will be eligible for pooling. 
The following center pooling algorithm will be used for each geographic region: 
 If a center has 15 or more subjects, then no pooling will be done for that center. 
 Centers with fewer than 15 subjects will be ordered from largest to smallest with pooling 
proceeding in the following manner: 
 Two or more centers will be combined until the cumulative subject total is at least 15. 
 Once a pooled center has at least 15 subjects, the process will continue in an iterative 
fashion for the subsequent centers in the ordered list, where a new pooled center begins 
each time at least 15 subjects has been reached in the previous pool. 
 If this iterative process reaches the end of the ordered list of centers where the final 
pooled center has fewer than 15 subjects, then the subjects from the centers in that pool 
will be combined with the pooled center formed in the previous iteration. 
This procedure is only to be performed within a geographic region – there will be no pooling of 
centers across regions. 
If the center-by-treatment interaction is not found to be significant (α=0.10), then no further 
analyses will be performed. On the other hand, if the interaction is significant, further analyses 
will be conducted to determine which center or centers may be the source of the interaction. This 
will be done by running the logistic regression model (including the interaction term) where each 
center will be systematically removed from the model. The impact of a given center will be 
based on the change in the interaction p-value when that center is removed. The center or centers 
that appear to be driving the significant interaction effect will then be removed from the model to 
verify that conclusions remain the same with or without the influential center(s). 
Additional sensitivity analyses to evaluate varying assumptions related to the handling of 
missing data will also be performed and are described in greater detail in Section 14.7. 
14.3.2 
Other efficacy analyses 
14.3.2.1 
Analysis of the secondary efficacy variables 
14.3.2.1.1 
Initial Treatment Period 
The secondary efficacy variables for time points during the Initial Treatment Period will be 
analyzed for all subjects in the RS. 
For comparisons with adalimumab at Week 16, the 2 bimekizumab arms will be pooled.  
For binary secondary efficacy variables, the stratified CMH test as specified for the primary 
analysis will be implemented to test for superiority of bimekizumab to adalimumab. As in the 
primary analysis, NRI will be used to account for missing data. 
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Sensitivity analyses for the handling of missing data will be performed for the secondary efficacy 
variables that are part of the fixed sequence testing procedures. These analyses are described in 
Section 14.7. 
14.3.2.1.2 
Maintenance Treatment Period 
The secondary efficacy variables in the Maintenance Treatment Period include PASI90, 
PASI100, and IGA at Week 24 and Week 56.  
In order to differentiate between subjects remaining on Q4W dosing from those switching to 
Q8W dosing at Week 16, the treatment comparisons at Week 24 for PASI100, PASI90 and IGA 
will be performed in 2 different ways using the following randomized treatment arms: 
1. Bimekizumab Q4W and bimekizumab  Q4W/Q8W combined vs adalimumab (testing H7, H8, 
and H9) 
2.  Bimekizumab Q4W only vs adalimumab (testing H10, H11, and H12) 
Since all subjects on adalimumab will be switched to bimekizumab at Week 24, the assessment 
of PASI90 and IGA at Week 56 will be for bimekizumab at the Q4W and Q8W dosing intervals. 
These summaries will include descriptive statistics by bimekizumab dose regimens at Week 24 
and Week 56 based on the RS. Subjects with missing data at Week 56 or who discontinue study 
treatment prior to Week 56 will be imputed via NRI. 
14.3.2.2 
Analysis of the other efficacy variables 
The other efficacy variables will be analyzed for all subjects in the RS.  
Binary (responder) variables will be summarized using frequency tables by treatment group for 
each visit. 
Continuous variables will be summarized using descriptive statistics by treatment group for each 
visit. 
Time to PASI50/75/90/100 response during the Initial Treatment Period will be estimated and 
presented using the Kaplan-Meier product-limit method for each treatment. Time to a given 
response will be defined as the length in days from the first dose of IMP until the first date when 
the response is achieved. Subjects who discontinue IMP prior to achieving a response will be 
censored at the date of IMP discontinuation. Subjects who reach the Week 24 Visit without 
achieving the given PASI response will be censored at the date of the Week 24 Visit. The median 
time to response, including the 2-sided 95% CI, will be calculated for each treatment. Between 
group differences will be analyzed with the log-rank statistic. 
All other efficacy variables will be summarized based on imputed data (NRI and multiple 
imputation for binary and continuous variables, respectively, unless otherwise specified in the 
SAP). In some cases, variables may also be summarized based on observed case data (ie, 
subjects with missing data or who have prematurely discontinued IMP are treated as missing). 
There may be cases where the multiple imputation model fails to converge. In such situations, 
the last observation carried forward (LOCF) approach will instead be used to impute the missing 
data. If LOCF is used instead of multiple imputation for this reason, this will be clearly specified 
in the corresponding table summary. Should there be no missing data for a study variable, then 
only observed case data will be presented. Note that for LOCF imputation, any missing data or 
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data collected following discontinuation of IMP will be imputed with the most recent previous 
value. See Section 14.7 for further details. 
14.4 
Subgroup analyses 
Subgroup analyses will be performed on the primary and secondary efficacy variables that are 
part of the fixed sequence testing procedure described in Section 14.3. The following variables 
for subgroup analyses will be defined: age, gender, disease duration, region, weight, body mass 
index (BMI), prior systemic chemotherapy or phototherapy, prior biologic exposure, prior 
systemic therapy of any kind, Baseline disease severity, and antibody positivity. These 
summaries will be based on imputed data (NRI) and will include descriptive statistics only  
14.5 
Planned safety and other analyses 
14.5.1 
Safety analyses 
Safety variables will be analyzed for all subjects in the SS. Additional summaries focusing on 
safety during the Maintenance Treatment Period will also be prepared and will be based on the 
RS. 
Adverse events will be coded according to the Medical Dictionary for Regulatory Activities 
(MedDRA®). Adverse events will be summarized descriptively by treatment group, primary 
system organ class, High Level Term (HLT), and preferred term. Additional tables will 
summarize AEs by intensity and relationship to IMP, AEs leading to withdrawal from the study, 
SAEs, and deaths. Specific safety topics of interest will be summarized and will be described in 
greater detail in the SAP. 
For subjects who switch treatment, AEs will be allocated to the treatment the subject was on the 
day the event occurred. If the event occurs on the day of the switch, it will be attributed to the 
initial treatment, unless the event has a HLT of “Injection Site Reactions”, in which case it will 
be attributed to the new treatment. Because the safety of switching from adalimumab to 
bimekizumab treatment is of particular interest, additional summaries to evaluate this will be 
specified in the SAP. 
Laboratory values (including markedly abnormal labs), urinary values, vital signs, and extent of 
exposure will be presented descriptively by treatment group. Definitions for markedly abnormal 
laboratory values will be provided in the SAP. 
14.5.2 
Pharmacokinetic analyses 
Pharmacokinetic variables will be analyzed for all subjects in the PK-PPS. Bimekizumab plasma 
concentrations will be summarized for each treatment at each scheduled visit. 
14.5.3 
Immunogenicity analyses 
Anti-bimekizumab antibodies will be assessed using a tiered approach: screening, confirmatory, 
and titer assays will be used. Anti-bimekizumab antibodies (including positivity) will be 
summarized by treatment at each scheduled visit at which samples are collected. 
14.6 
Handling of protocol deviations 
Important protocol deviations are deviations from the protocol which potentially could have a 
meaningful impact on study conduct, or on the primary efficacy, key safety, or PK outcomes for 
an individual subject. The criteria for identifying important protocol deviations will be defined 
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within the appropriate protocol-specific document at study start. Important protocol deviations 
will be reviewed as part of the ongoing data cleaning process and all important deviations will be 
identified and documented prior to unblinding to confirm exclusion from analysis sets. 
14.7 
Handling of dropouts or missing data 
Study variables with multiple components may have rules to account for partial missing data of 
1 or more components. Such rules will be defined in the SAP. The following rules are outlined 
for cases where variables are completely missing, including partial missing data where the data 
handling rules conclude that the variable should be treated as completely missing. 
The analysis of the co-primary efficacy variables will use NRI for handling of missing data. That 
is, subjects with missing data or who have discontinued IMP prior to Week 16 will be considered 
as nonresponders for the primary analysis. The following sensitivity analyses for the co-primary 
efficacy variables will be performed: 
1. Missing data will be addressed by using multiple imputation (Markov-Chain Monte Carlo 
[MCMC] method for intermittent missing data, followed by monotone regression for 
monotone missing data) to evaluate the effect of the method for handling missing data on the 
analysis. The actual PASI/IGA scores will be imputed and then dichotomized to obtain the 
response status. The treatment differences for each imputed data set will subsequently be 
evaluated using the stratified CMH test as used in the primary analysis. The results from each 
of the imputed data sets will be combined for overall inference using Rubin’s rules, which 
account for the uncertainty associated with the imputed values (Rubin, 1987). This will be 
done using SAS PROC MIANALYZE. This procedure assumes a missing at random (MAR) 
pattern of missingness and corresponds to an estimand of the difference in outcome 
improvement if all subjects tolerated or adhered to treatment (Mallinckrodt et al, 2012). This 
is an estimand of efficacy to evaluate the de jure hypothesis. 
2. Deviations from the MAR pattern assumed above will be evaluated. A sensitivity analysis 
will be performed in which, as with the above analysis, intermittent missing data will be 
imputed using multiple imputation (MI) based on the MCMC method. However, the 
remaining monotone missing data will be assumed to follow a missing not at random pattern. 
These data will be imputed using reference-based imputation. Typically, reference-based 
imputation uses an imputation model based on data from the placebo group, thereby 
assuming that monotone missing data follow a trajectory similar to the placebo group 
(Mallinckrodt et al, 2012). Since there is no placebo group in this study, and because it is 
assumed that bimekizumab is more efficacious than adalimumab, the adalimumab arm will 
be used as the reference arm. As specified in the previous procedure, actual PASI/IGA scores 
will be imputed and then dichotomized to get the response status. The treatment differences 
for each imputed data set will subsequently be evaluated using the stratified CMH test as 
used in the primary analysis. The estimand in this procedure is the difference in outcome 
improvement in all randomized subjects at the planned endpoint of the study attributable to 
the initially randomized medication (Mallinckrodt et al, 2012). This is an estimand of 
effectiveness to evaluate the de facto hypothesis. 
3. A final sensitivity analysis will be based on observed data at Week 16. Subjects with missing 
data or who have prematurely discontinued study treatment will be treated as missing. The 
same CMH test as in the primary efficacy analysis will be used. 
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Further details on the MI procedures will be provided in the SAP. 
Missing data for binary secondary variables during the Initial Treatment Period will be imputed 
using NRI. 
For the secondary endpoints evaluated at Week 56 (based on the RS), all subjects with missing 
data at Week 56 or who discontinue study treatment prior to Week 56 will be counted as 
nonresponders. 
For other continuous efficacy variables, MI will be used to impute missing data when possible. If 
the imputation model cannot converge, LOCF will be used. The MI procedure will be similar to 
sensitivity analysis #1 described above with the following differences: 1) the imputation model 
will use the change from Baseline (instead of actual) values by visit and no dichotomization will 
be necessary; 2) instead of using the stratified CMH test, the imputed data sets will be combined 
and simple means and standard errors will be calculated using Rubin’s rules (via SAS PROC 
MIANALYZE). For calculation of other descriptive statistics such as the median, min and max, 
Rubin's rules do not apply. Multiple imputation estimates will be computed by simply averaging 
the estimates from the multiple repetitions of the imputation algorithm. 
14.8 
Planned interim analysis and data monitoring 
After the final Week 56 visit, an interim analysis will be performed and a corresponding interim 
CSR may be written. A final analysis and updated final CSR will be prepared once all data 
(through the SFU visit) have been collected. 
14.9 
Determination of sample size 
A total of 450 subjects will be randomly assigned in a 1:1:1 ratio to the following treatment 
groups: 
 Bimekizumab 320mg Q4W throughout the study (150 subjects) 
 Bimekizumab 320mg Q4W/Q8W (ie, bimekizumab 320mg Q4W until Week 16, then 
bimekizumab 320mg Q8W from Week 16 through Week 52 (150 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg Q2W starting 1 week 
after the initial dose (ie, adalimumab will be administered according to the labeling 
recommendations) until Week 24, then bimekizumab 320mg Q4W from Week 24 to 
Week 52 (150 subjects) 
When comparing bimekizumab to adalimumab, the assumed responder rates for PASI90 and 
IGA at Week 16 for the bimekizumab group are 75% and 85%, respectively. These estimates are 
based on the results of the Phase 2b PS0010 study. The PASI90 responder rates at Week 16 for 
adalimumab from the VOYAGE-1 and VOYAGE-2 studies were 50% and 47%, respectively 
(Blauvelt et al, 2017; Reich et al, 2017). Additionally, the IGA responder rates at Week 16 for 
adalimumab in VOYAGE-1 and VOYAGE-2 were 66% and 68%, respectively. For the purposes 
of these sample size calculations at Week 16, we assume a PASI90 responder rate and IGA 
responder rate for adalimumab of 50% and 68%, respectively. 
The testing procedure described in Section 14.3 indicates that the first test will be to demonstrate 
noninferiority to adalimumab for the co-primary variables of PASI90 and IGA at Week 16. If 
non-inferiority for both tests is demonstrated, then superiority to adalimumab will be tested. 
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Because the superiority evaluation is the more stringent test, sample size calculations are based 
on the testing of superiority to adalimumab for PASI90 and IGA at Week 16. Given these 
assumptions and a sample size of 150 subjects in the adalimumab arm and 300 subjects in the 
pooled bimekizumab arms, the power to detect a statistically significant difference between 
bimekizumab and adalimumab is >99% for PASI90 response and 97% for IGA response. This 
assumes a 2-sided significance level of 0.05. Because both co-primary endpoints are highly 
powered independently, and because PASI and IGA response tend to be highly correlated, the 
overall power for achieving superiority on both co-primary endpoints is not calculated here. 
Note that the non-inferiority testing procedure will be based on a 1-sided significance level of 
0.025 and a non-inferiority margin of 10%. The power to demonstrate non-inferiority to 
adalimumab using the other assumptions described above is >99% for both PASI90 and IGA 
responses. 
15 
ETHICS AND REGULATORY REQUIREMENTS 
15.1 
Informed consent 
Subject’s informed consent must be obtained and documented in accordance with local 
regulations, ICH-GCP requirements, and the ethical principles that have their origin in the 
principles of the Declaration of Helsinki. 
Prior to obtaining informed consent, information should be given in a language and at a level of 
complexity understandable to the subject in both oral and written form by the Investigator (or 
designee). Each subject will have the opportunity to discuss the study and its alternatives with 
the Investigator. 
Prior to participation in the study, the ICF should be signed and personally dated by the subject 
and by the person who conducted the informed consent discussion (Investigator or designee). 
The subject must receive a copy of the signed and dated ICF. As part of the consent process, 
each subject must consent to direct access to his/her medical records for study-related 
monitoring, auditing, IRB/IEC review, and regulatory inspection. 
If the ICF is amended during the study, the Investigator (or the Sponsor, if applicable) must 
follow all applicable regulatory requirements pertaining to the approval of the amended ICF by 
the IRB/IEC and use of the amended form. 
All studies conducted at centers in the United States must include the use of a Health Insurance 
Portability and Accountability Act Authorization Form. 
The subject may withdraw his/her consent to participate in the study at any time. A subject is 
considered as enrolled in the study when he/she has signed the ICF. An eCRF must not be 
started, nor may any study-specific procedure be performed for a given subject, without having 
obtained his/her written consent to participate in the study. 
15.2 
Subject identification cards 
Upon signing the Informed Consent and Assent Form (as applicable), the subject will be 
provided with a subject identification card in the language of the subject. The Investigator will 
fill in the subject identifying information and medical emergency contact information. The 
Investigator will instruct the subject to keep the card with him/her at all times. 
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15.3 
Institutional Review Boards and Independent Ethics 
Committees 
The study will be conducted under the auspices of an IRB/IEC, as defined in local regulations, 
ICH-GCP, and in accordance with the ethical principles that have their origin in the Declaration 
of Helsinki. 
The Investigator/UCB will ensure that an appropriately constituted IRB/IEC that complies with 
the requirements of the current ICH-GCP version or applicable country-specific regulations will 
be responsible for the initial and continuing review and approval of the clinical study. Prior to 
initiation of the study, the Investigator/UCB will forward copies of the protocol, ICF, IB, 
Investigator’s curriculum vitae (if applicable), advertisement (if applicable), and all other 
subject-related documents to be used for the study to the IRB/IEC for its review and approval. 
Before initiating a study, the Investigator will have written and dated full approval from the 
responsible IRB/IEC for the protocol. 
The Investigator will also promptly report to the IRB/IEC all changes in the study, all 
unanticipated problems involving risks to human subjects or others, and any protocol deviations, 
to eliminate immediate hazards to subjects. 
The Investigator will not make any changes in the study or study conduct without IRB/IEC 
approval, except where necessary to eliminate apparent immediate hazards to the subjects. For 
minor changes to a previously approved protocol during the period covered by the original 
approval, it may be possible for the Investigator to obtain an expedited review by the IRB/IEC as 
allowed. 
As part of the IRB/IEC requirements for continuing review of approved studies, the Investigator 
will be responsible for submitting periodic progress reports to the IRB/IEC (based on IRB/IEC 
requirements), at intervals appropriate to the degree of subject risk involved, but no less than 
once per year. The Investigator should provide a final report to the IRB/IEC following study 
completion. 
UCB (or its representative) will communicate safety information to the appropriate regulatory 
authorities and all active Investigators in accordance with applicable regulatory requirements. 
The appropriate IRB/IEC will also be informed by the Investigator or the Sponsor, as specified 
by the applicable regulatory requirements in each concerned country. Where applicable, 
Investigators are to provide the Sponsor (or its representative) with evidence of such IRB/IEC 
notification. 
15.4 
Subject privacy 
UCB staff (or designee) will affirm and uphold the subject’s confidentiality. Throughout this 
study, all data forwarded to UCB (or designee) will be identified only by the subject number 
assigned at Screening. 
The Investigator agrees that representatives of UCB, its designee, representatives of the relevant 
IRB/IEC, or representatives of regulatory authorities will be allowed to review that portion of the 
subject’s primary medical records that directly concerns this study (including, but not limited to, 
laboratory test result reports, ECG reports, admission/discharge summaries for hospital 
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admissions occurring during a subject’s study participation, and autopsy reports for deaths 
occurring during the study). 
15.5 
Protocol amendments 
Protocol changes may affect the legal and ethical status of the study and may also affect the 
statistical evaluations of sample size and the likelihood of the study fulfilling its primary 
objective. 
Significant changes to the protocol will only be made as an amendment to the protocol and must 
be approved by UCB, the IRB/IEC, and the regulatory authorities (if required), prior to being 
implemented. 
16 
FINANCE, INSURANCE, AND PUBLICATION 
Insurance coverage will be handled according to local requirements. 
Finance, insurance, and publication rights are addressed in the Investigator and/or CRO 
agreements, as applicable. 
17 
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Parisi R, Symmons DP, Griffiths CE, Ashcroft DM, Identification and Management of Psoriasis 
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18 
APPENDICES 
18.1 
Protocol Amendment 1 
Rationale for the amendment 
The purpose of this amendment was the following:   
 Remove re-randomization at Week 24. Subjects in the bimekizumab groups will be allocated 
to bimekizumab 320mg Q4W throughout the study or bimekizumab 320mg Q4W through 
Week 16 and bimekizumab 320mg Q8W thereafter 
 Remove change in dose based on PASI90 response 
 Update the study design so subjects in the bimekizumab Q4W/Q8W arm switch at Week 16 
instead of Week 24 
 Add a new other efficacy variable (absolute and percent change from Baseline in the product 
of IGA and BSA [IGAxBSA]) 
 Add assessment of the Patient Symptom Diary (daily) to the Screening and Week 16 Visits 
 Clarify the dosing window 
 Add percentage of BSA as an assessments at all visits 
 Clarify that PGADA will be performed on all subjects at Baseline 
 Remove the criterion that excluded subjects exposed to more than 3 biologic response 
modifiers (including no more than 1 IL-17) 
 Clarify that subjects who experienced primary failure (no response within 12 weeks) to 1 or 
more IL-17 biologic response modifiers or more than 1 biologic response modifiers other 
than an IL-17 should be excluded from the study 
 Remove the withdrawal criterion that subjects who do not achieve a PASI50 response by 
Week 28 or later be withdrawn from the study 
 Corrected discrepancies between Section 8 Study procedures by visit and Table 5-1 Schedule 
of study assessments 
 Clarify that the same assessor should evaluate the subject at each efficacy assessment 
 Clarify in footnote c of Table 12-2 Laboratory measurements the visits in which the urine 
drug screen will be performed 
 Update the assessment and management of TB and TB risk factors 
 Update the sequence testing and analysis of secondary efficacy variables 
In addition, minor spelling, editorial, and formatting changes were made, and the List of 
abbreviations was updated. 
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Modifications and changes 
Specific changes 
Change #1  
Title page 
A PHASE 3, MULTICENTER, RANDOMIZED, DOUBLE-BLIND STUDY WITH A 24-
WEEK ACTIVE-CONTROLLED INITIAL TREATMENT PERIOD FOLLOWED BY A 32-
WEEK, DOSE-BLIND MAINTENANCE TREATMENT PERIOD TO EVALUATE THE 
EFFICACY AND SAFETY OF BIMEKIZUMAB IN ADULT SUBJECTS WITH 
MODERATE TO SEVERE CHRONIC PLAQUE PSORIASIS 
Has been changed to: 
A PHASE 3, MULTICENTER, RANDOMIZED, DOUBLE-BLIND STUDY WITH AN 24
WEEK ACTIVE-CONTROLLED INITIAL TREATMENT PERIOD FOLLOWED BY A 32
WEEK, DOSE-BLIND MAINTENANCE TREATMENT PERIOD TO EVALUATE THE 
EFFICACY AND SAFETY OF BIMEKIZUMAB IN ADULT SUBJECTS WITH 
MODERATE TO SEVERE CHRONIC PLAQUE PSORIASIS 
Change #2 
Section 1 Summary 
Approximately 540 subjects will be screened in order to have a total of 400 subjects randomized 
in the study. For each subject, the study will last a maximum of 76 weeks and will consist of 
4 periods, a Screening Period (2 to 4 weeks), a double-blind, active comparator-controlled Initial 
Treatment Period (24 weeks), a dose-blind Maintenance Treatment Period (32 weeks), and a 
Safety Follow-Up (SFU) Period (20 weeks after the last dose of the investigational medicinal 
product [IMP]). After completion of the 32-week Maintenance Treatment Period, eligible 
subjects will be allowed to enroll in an open-label study. 
During the Treatment Period, eligible subjects will be randomized 1:1 to receive the following 
blinded IMP regimens subcutaneously (sc): 
Double-blind Initial Treatment Period: 
 Bimekizumab 320mg administered Q4W (200 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg every 2 weeks (Q2W) 
starting 1 week after the initial dose (ie, adalimumab will be administered according to the 
labeling recommendations) (200 subjects) 
Dose-blind Maintenance Treatment Period: 
From Week 24 onwards, subjects will be treated as follows: 
 Subjects in the bimekizumab 320mg Q4W treatment arm who do not achieve a PASI90 
response at Week 24 will continue to receive bimekizumab 320mg Q4W. 
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 Subjects in the bimekizumab 320mg Q4W treatment arm who achieve a PASI90 response at 
Week 24 will be re-randomized 1:1 to receive bimekizumab 320mg Q4W or bimekizumab 
320mg Q8W. 
 Subjects in the adalimumab treatment arm will receive bimekizumab 320mg Q4W. 
Bimekizumab will be administered in the clinic at Baseline and Q4W or Q8W thereafter, through 
Week 52. An initial dose of the active comparator, adalimumab 80mg, will be administered at 
Baseline followed by adalimumab 40mg Q2W from Week 1 through Week 23. 
Subjects who do not have a PASI50 response at Week 36 or later will be withdrawn from the 
study. 
At Week 56, all subjects enrolling in the open-label study will undergo the Week 56 study 
assessments before receiving their first open-label study dose of IMP. All subjects not enrolling 
in the open-label study will have the Week 56 study assessments and will enter the 20-week 
SFU Period. 
Has been changed to: 
Approximately 600540 subjects will be screened in order to have a total of 450400 subjects 
randomized in the study. For each subject, the study will last a maximum of 76 weeks and will 
consist of 4 periods, a Screening Period (2 to 4 weeks), a double-blind, active comparator-
controlled Initial Treatment Period (1624 weeks), a dose-blind Maintenance Treatment Period 
(4032 weeks), and a Safety Follow-Up (SFU) Period (20 weeks after the last dose of the 
investigational medicinal product [IMP]). After completion of the 4032-week Maintenance 
Treatment Period, eligible subjects will be allowed to enroll in an open-label study. 
During the Treatment Period, eEligible subjects will be randomized 1:1:1 to receive the 
following blinded IMP regimens subcutaneously (sc): 
Double blind Initial Treatment Period: 
 Bimekizumab 320mg Q4W administered Q4Wthroughout the study (150200 subjects) 
 Bimekizumab 320mg Q4W/Q8W (ie, bimekizumab 320mg will be administered through 
Week 12, then bimekizumab 320mg Q8W from Week 16 through Week 52 
(150 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg every 2 weeks (Q2W) 
starting 1 week after the initial dose (ie, adalimumab will be administered according to the 
labeling recommendations) until Week 24, then bimekizumab Q4W from Week 24 to 
Week 52 (150200 subjects) 
Dose blind Maintenance Treatment Period: 
From Week 24 onwards, subjects will be treated as follows: 
 Subjects in the bimekizumab 320mg Q4W treatment arm who do not achieve a PASI90 
response at Week 24 will continue to receive bimekizumab 320mg Q4W. 
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 Subjects in the bimekizumab 320mg Q4W treatment arm who achieve a PASI90 
response at Week 24 will be re randomized 1:1 to receive bimekizumab 320mg Q4W or 
bimekizumab 320mg Q8W. 
 Subjects in the adalimumab treatment arm will receive bimekizumab 320mg Q4W. 
Bimekizumab will be administered in the clinic at Baseline and Q4W or Q8W thereafter, 
through Week 52. An initial dose of the active comparator, adalimumab 80mg, will be 
administered at Baseline followed by adalimumab 40mg Q2W from Week 1 through 
Week 23. 
Subjects who do not have a PASI50 response at Week 36 or later will be withdrawn from 
the study. 
Change #3  
Section 2.1.2 Current treatments for psoriasis 
 Brodalumab has been approved in the US for the treatment of moderate to severe plaque 
psoriasis in adult patients who are candidates for systemic therapy or phototherapy and 
have failed to respond or have lost response to other systemic therapies. Brodalumab is a 
human monoclonal IgG2 antibody that selectively binds to human IL-17RA and inhibits 
its interactions with cytokines IL-17A, IL-17F, IL-17C, IL-17A/F heterodimer and IL-25. 
Blocking IL 17RA inhibits IL-17 cytokine-induced responses including the release of 
pro-inflammatory cytokines and chemokines  Brodalumab has a black box warning 
regarding suicidal ideation and behavior  
Has been changed to: 
 Brodalumab has been approved in the US for the treatment of moderate to severe plaque 
psoriasis in adult patients who are candidates for systemic therapy or phototherapy and 
have failed to respond or have lost response to other systemic therapies. In the EU, 
brodalumab is indicated for the treatment of moderate to severe plaque PSO in 
adult patients who are candidates for systemic therapy. Brodalumab is a human 
monoclonal IgG2 antibody that selectively binds to human IL-17RA and inhibits its 
interactions with cytokines IL-17A, IL-17F, IL-17C, IL-17A/F heterodimer and IL-25. 
Blocking IL 17RA inhibits IL-17 cytokine-induced responses including the release of 
pro-inflammatory cytokines and chemokines. Brodalumab has a black box warning 
regarding suicidal ideation and behavior. 
Change #4  
Section 2.2.1.1 
Completed studies 
Four clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with mild to 
moderate plaque PSO, RA0124 in 30 healthy volunteers, PA0007 in 53 subjects with PsA, and 
UP0031 in 12 healthy volunteers. Three studies (RA0123, PS0010, and PS0016) are ongoing in 
subjects with moderate to severe rheumatoid arthritis (RA0123) and in subjects with moderate to 
severe PSO (PS0010 and PS0016). 
Has been changed to: 
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Four clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with mild to 
moderate plaque PSO, RA0124 in 30 healthy volunteers, PA0007 in 53 subjects with PsA, and 
UP0031 in 12 healthy volunteers. Three studies (RA0123, PS0010, and PS0016) are ongoing 
in subjects with moderate to severe rheumatoid arthritis (RA0123) and in subjects with 
moderate to severe PSO (PS0010 and PS0016). 
Change #5  
Section 2.2.1.2 
Ongoing studies 
Five additional studies of bimekizumab in the treatment of PSO are ongoing. 
Has been changed to: 
Four additional studies of bimekizumab in the treatment of PSO and 1 study in healthy 
volunteers are ongoing. Five additional studies of bimekizumab in the treatment of PSO 
are ongoing. 
Change #6  
Section 4.3.1 Other efficacy variables 
Change from Baseline variables evaluated during the Initial Treatment Period, are relative to the 
Baseline (first dose) Visit. For subjects who switch treatment at the Week 24 Visit, change from 
Baseline variables during the Maintenance Treatment Period may be evaluated relative to both 
the Baseline (first dose) Visit and the Week 24 Visit  
Has been changed to: 
Change from Baseline variables evaluated during the Initial Treatment Period, are relative to 
the Baseline (first dose) Visit. In addition, Ffor subjects who started with adalimumab and 
switch treatment at the Week 24 Visit, change from Baseline variables during the Maintenance 
Treatment Period may be evaluated relative to both the Baseline (first dose) Visit and the 
Week 24 Visit.  
Change #7  
Section 4.3.1 Other efficacy variables 
The following bullet has been added: 
 Absolute and percent change from Baseline in the product of IGA and BSA (IGAxBSA) 
Change #8 
Section 5.1 
Study description  
PS0008 is a Phase 3, multicenter study consisting of a 24-week, randomized, double-blind, 
parallel-group, active-comparator-controlled Initial Treatment Period followed by a 32-week, 
Maintenance Treatment Period to evaluate the efficacy and safety of bimekizumab in adult 
subjects with moderate to severe chronic plaque PSO. To be eligible to participate in this study, 
subjects must be adults with a diagnosis of moderate to severe PSO (Baseline PASI ≥12 and 
BSA affected by PSO ≥10% and IGA score ≥3 [on a 5-point scale]) who are candidates for 
systemic PSO therapy and/or phototherapy and/or photochemotherapy. Up to 30% of subjects 
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may have been previously exposed to a biologic therapy (see Exclusion Criteria #22 and #23, 
Section 6.2). 
Has been changed to: 
PS0008 is a Phase 3, multicenter study consisting of a 1624-week, randomized, double-blind, 
parallel-group, active-comparator-controlled Initial Treatment Period followed by a 4032-week, 
Maintenance Treatment Period to evaluate the efficacy and safety of bimekizumab in adult 
subjects with moderate to severe chronic plaque PSO. To be eligible to participate in this study, 
subjects must be adults with a diagnosis of moderate to severe PSO (Baseline PASI ≥12 and 
BSA affected by PSO ≥10% and IGA score ≥3 [on a 5-point scale]) who are candidates for 
systemic PSO therapy and/or phototherapy and/or photochemotherapy. Adalimumab will be 
administered per the local label. Up to 30% of subjects may have been previously exposed to a 
biologic therapy (see Exclusion Criterion #22 and #23, Section 6.2). 
Change #9 
Section 5.2 
Study periods 
This study will include 4 periods, a Screening Period (2 to 4 weeks), an Initial Treatment Period 
(24 weeks), a Maintenance Treatment Period (32 weeks), and a SFU Period (20 weeks after the 
last dose of IMP). After completion of the Maintenance Treatment Period, eligible subjects will 
be allowed to enroll in an open-label study. Subjects enrolling into the open-label study will not 
have the PS0008 SFU Visit. 
Has been changed to: 
This study will include 4 periods, a Screening Period (2 to 4 weeks), an Initial Treatment Period 
(1624 weeks), a Maintenance Treatment Period (4032 weeks), and a SFU Period (20 weeks after 
the last dose of IMP). After completion of the Maintenance Treatment Period, eligible subjects 
will be allowed to enroll in an open-label study. Subjects enrolling into the open-label study will 
not have the PS0008 SFU Visit. 
Change #10 
Section 5.2.2 Double-blind Initial Treatment Period 
During the active-controlled 24-week Initial Treatment Period, approximately 400 subjects will 
be randomized 1:1 to receive the following blinded IMP regimens: 
 Bimekizumab 320mg administered sc Q4W (200 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg every Q2W starting 
1 week after the initial dose (ie, adalimumab will be administered according to the labeling 
recommendations) (200 subjects) 
Has been changed to: 
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During the active-controlled 1624-week Initial Treatment Period, approximately 450400 subjects 
will be randomized 1:1:1 to receive the following blinded IMP regimens: 
 Bimekizumab 320mg administered sc Q4W throughout the study (150200 subjects) 
 Bimekizumab 320mg administered Q4W until Week 16 (150 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg every Q2W starting 
1 week after the initial dose (ie, adalimumab will be administered according to the labeling 
recommendations) until Week 24 (150200 subjects) 
Change #11 
Section 5.2.3 Dose-blind Maintenance Treatment Period 
After the 24-week Initial Treatment Period, subjects will enter the 32-week Maintenance 
Treatment Period. Treatment during the Maintenance Treatment Period will start at Week 24 and 
subjects will return to the clinic Q4W through Week 56. The IMP will be administered in the 
clinic by sc injection at the time points specified in the schedule of study assessments 
(Table 5-1). Treatment during the Maintenance Treatment Period will be based on initial 
treatment and response to treatment at Week 24, per the following rules: 
 Subjects in the bimekizumab 320mg Q4W treatment arm who do not achieve a PASI90 
response at Week 24 will continue to receive bimekizumab 320mg Q4W. 
 Subjects in the bimekizumab 320mg Q4W treatment arm who achieve a PASI90 response at 
Week 24 will be re-randomized 1:1 to receive bimekizumab 320mg Q4W or bimekizumab 
320mg Q8W. 
 Subjects in the adalimumab treatment arm will receive bimekizumab 320mg Q4W. 
Subjects may receive placebo injections at certain visits in order to blind the IMP (see 
Section 7.2). 
If a subject does not achieve a PASI50 response at Week 36 or later, the subject will be 
withdrawn from the study at the time point when the PASI50 response is not achieved. 
Has been changed to: 
After the 1624-week Initial Treatment Period, subjects will enter the 4032-week Maintenance 
Treatment Period. Treatment during the Maintenance Treatment Period will start at Week 1624 
and subjects will return to the clinic Q4W or Q8W through Week 56. The IMP will be 
administered in the clinic by sc injection at the time points specified in the schedule of study 
assessments (Table 5-1). Treatment during the Maintenance Treatment Period will be based on 
initial treatment and response to treatment at Week 24, per the following rules: 
 Subjects in the bimekizumab 320mg Q4W treatment arm who do not achieve a PASI90 
response at Week 24 will continue to receive bimekizumab 320mg Q4W. 
 Subjects in the bimekizumab 320mg Q4W treatment arm who achieve a PASI90 
response at Week 24 will be re randomized 1:1 to receive bimekizumab 320mg Q4W or 
bimekizumab 320mg Q8W. Subjects in the bimekizumab 320mg Q4W/Q8W treatment 
arm will receive bimekizumab Q8W from Week 16 through Week 52. 
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 Subjects in the adalimumab treatment arm will bimekizumab 320mg Q4W from Week 24 to 
Week 52. 
Subjects may receive placebo injections at certain visits in order to blind the IMP (see 
Section 7.2). 
If a subject does not achieve a PASI50 response at Week 36 or later, the subject will be 
withdrawn from the study at the time point when the PASI50 response is not achieved. 
Change #12 
Section 5.3 
Study duration per subject 
For each subject, the study will last a maximum of up to 76 weeks, as follows: 
 Screening Period: 2 to 4 weeks 
 Double-blind, active-controlled Initial Treatment Period: 24 weeks 
 Maintenance Treatment Period: 32 weeks 
 Safety Follow-Up Period: a SFU Visit is planned 20 weeks after the last dose of IMP (for 
subjects not enrolling in the open-label study) 
After the 32-week Maintenance Treatment Period, subjects will be allowed to enroll in an open-
label study, in which case subjects will undergo the Week 56 study assessments before receiving 
their first open-label IMP dose. The SFU Visit will not be required for subjects who enroll in the 
open-label study. 
Has been changed to: 
For each subject, the study will last a maximum of up to 76 weeks, as follows: 
 Screening Period: 2 to 4 weeks 
 Double-blind, active-controlled Initial Treatment Period: 1624 weeks 
 Maintenance Treatment Period: 4032 weeks 
 Safety Follow-Up Period  a SFU Visit is planned 20 weeks after the last dose of IMP (for 
subjects not enrolling in the open-label study) 
After the 4032-week Maintenance Treatment Period, subjects will be allowed to enroll in an 
open-label study, in which case subjects will undergo the Week 56 study assessments before 
receiving their first open-label IMP dose. The SFU Visit will not be required for subjects who 
enroll in the open-label study. 
Change #13 
Section 5.4 
Planned number of subjects and site(s) 
Approximately 540 subjects will be screened in order to have 400 subjects randomized in the 
study. There will be approximately 200 subjects per treatment arm. The planned number of study 
sites is approximately 100. Every eligible subject who signs an ICF will be expected to be 
randomized. 
Has been changed to: 
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Approximately 600540 subjects will be screened in order to have 450400 subjects randomized in 
the study. There will be approximately 150200 subjects per treatment arm. The planned number 
of study sites is approximately 100. Every eligible subject who signs an ICF will be expected to 
be randomized. 
Change #14 
Table 5-1 Schedule of study assessments
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
Dose-blind Maintenance Treatment 
Period 
(weeks after first dose) 
W56PEO
T 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Informed consentc 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Xd 
 
 
Inclusion/exclusion 
X 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
Demographic data 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Psoriasis history 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Significant past 
medical history and 
concomitant 
diseases 
X Xe 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical 
examinationf,g 
X  
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Vital signsh 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and 
biochemistry 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
Urinalysis 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
ECG 
X  
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Pregnancy testingi 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
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Page 120 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
Dose-blind Maintenance Treatment 
Period 
(weeks after first dose) 
W56PEO
T 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Hepatitis B and C 
testingj 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV testingk 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest x-rayl 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IGRA Tuberculosis 
test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
Tuberculosis 
questionnaire 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
X 
 
X 
X 
X 
Blood sample for 
bimekizumab 
plasma 
concentrationsm 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
anti-bimekizumab 
antibodiesm 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample 
genomic, 
proteomic, and 
metabolomics, and 
candidate 
biomarker 
analysesc,m 
 
X 
X 
 
 
 
X 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
Dose-blind Maintenance Treatment 
Period 
(weeks after first dose) 
W56PEO
T 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Blood sample 
genetic/epigenetic 
analysesc,m 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PASI  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PHQ-9 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
eC-SSRS 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Patient Symptom 
Diary (daily)  
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
 
scalp IGA 
 
X 
Xn 
Xn 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
  
 
Xn  
Xn  
Xn  
Xn  
Xn 
 
mNAPSI 
 
X 
 
 
Xo 
 
Xo 
 
Xo 
 
Xo 
 
 
 
Xo  
Xo  
Xo  
Xo  
Xo 
 
pp-IGA 
 
X 
Xp 
Xp 
Xp 
 
Xp 
 
Xp 
 
Xp 
 
 
 
Xp  
Xp  
Xp  
Xp  
Xp 
 
EQ-5D-3L 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
SF-36 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Patient global 
assessment of 
psoriasisq 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PASE  
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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PS0008 
 
 
 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
Dose-blind Maintenance Treatment 
Period 
(weeks after first dose) 
W56PEO
T 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
PGADAr 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
WPAI-SHP V2.0 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Concomitant 
medication 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTs,t 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Bimekizumab, 
adalimumab, or 
placebo 
administrations,t 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Xu X 
X 
X 
X 
X 
X 
X 
 
 
CV=cardiovascular; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case Report Form; eC-SSRS=electronic Columbia Suicide Severity 
Rating Scale; EQ-5D-3L=Euro-Quality of Life 5-Dimensions 3 Levels; GI=gastrointestinal HIV=human immunodeficiency virus; ICF=Informed Consent Form; 
IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; IMP=investigational medicinal product; IRT=interactive response technology; PASE=Psoriatic 
Arthritis Screening and Evaluation; PASI=psoriasis area severity index; PEOT=Premature End of Treatment Visit; PGADA=Patient Global Assessment of Disease Activity; PHQ-
9=Patient Health Questionnaire-9; PsA=psoriatic arthritis; SF-36=Short Form 36-item Health Survey; SFU=Safety Follow-Up; scalp IGA=scalp-specific Investigator’s Global 
Assessment; TB=tuberculosis; VAS=visual analog scale; WPAI-SHP=Work Productivity and Activity Impairment Questionnaire-specific health problem 
a Visit windows of ±3 days from the first dose at all visits except SFU. The SFU Visit window is -3 and +7 days from last dose. 
b The SFU Visit will occur 20 weeks after the last dose. 
c A separate ICF will be required for subjects who decide to participate in the genomics, genetics, and proteomics substudy. The ICF must be signed prior to 
collecting any samples for the substudy  The samples will be stored at -80°C at the central biorepository for up to 20 years. 
d A separate ICF is required to be completed for the open-label study. 
e Ensure no significant changes in medical history. 
f Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
g The physical examination will include examination of the following systems: eyes, hair, and skin; respiratory; CV; and GI. 
h Vital signs (blood pressures, pulse rate, and temperature) are to be measured prior to blood sampling, and prior to dosing, where applicable. 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
Dose-blind Maintenance Treatment 
Period 
(weeks after first dose) 
W56PEO
T 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
i Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
j Subjects who have evidence of or test positive for hepatitis B by any of the following criteria: 1) positive for hepatitis B surface antigen (HBsAg+); 2) positive 
for anti-hepatitis B core antibody (HBcAb+) are excluded. A positive test for HCV is defined as  1) positive for hepatitis C antibody (anti-HCV Ab), and 
2) positive via a confirmatory test for HCV (for example, HCV polymerase chain reaction) are also excluded. Subjects will also be tested for anti-hepatitis B 
surface antibody. 
k The HIV test results will not be recorded in the eCRF. 
l Screening chest x-ray must occur within 3 months prior to Screening Visit. 
m All blood samples taken prior to dosing. 
n The scalp IGA will only be assessed for those subjects with scalp involvement (scalp IGA score >0) at Baseline. 
o The mNAPSI will be assessed only in subjects with nail involvement (mNAPSI score >0) at Baseline. 
p The pp-IGA will only be assessed in subjects with palmoplantar involvement (pp-IGA score >0) at Baseline. 
q The Patient Global Assessment of psoriasis will be performed as part of the patient symptoms diary on a weekly basis from baseline through the initial 
treatment period with a +3 day completion window. During the maintenance period this assessment will be completed at each clinic visit specified with a 
±3 day completion window. 
r The PGADA is assessed only for subjects with PsA at Baseline (defined as a past medical history of PsA or PASE ≥47). 
s IMP administration is based on randomization. 
t For bimekizumab, the minimum time between doses should be no less than 24 days and no more than 32 days. 
u At Week 24 subjects will be re-allocated based on original treatment and response to treatment and will receive their first Maintenance Treatment Period dose. 
Has been changed to: 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
Informed consentc 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Xd  
 
Inclusion/exclusion 
X X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
Demographic data 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Psoriasis history 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Significant past 
medical history 
and concomitant 
diseases 
X Xe 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical 
examinationf,g 
X  
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Vital signsh 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and 
biochemistry 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
Urinalysis 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
ECG 
X  
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Pregnancy testingi 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
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Page 125 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
Hepatitis B and C 
testingj 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV testingk 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest x-rayl 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IGRA Tuberculosis 
test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
Tuberculosis 
questionnaire 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
X 
 
X 
X 
X 
Blood sample for 
bimekizumab 
plasma 
concentrationsm 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
anti-bimekizumab 
antibodiesm 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample 
genomic, 
proteomic, and 
metabolomics, and 
candidate 
biomarker 
analysesc,m 
 
X 
X 
 
 
 
X 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 126 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
Blood sample 
genetic/epigenetic 
analysesc,m 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PASI  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Percentage of 
BSA 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PHQ-9 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
eC-SSRS 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Patient Symptom 
Diary (daily)  
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
scalp IGA 
 
X 
Xn 
Xn 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn  
Xn  
Xn  
Xn  
Xn 
 
mNAPSI 
 
X 
 
 
Xo 
 
Xo 
 
Xo 
 
Xo 
 
 Xo 
 
Xo  
Xo  
Xo  
Xo  
Xo 
 
pp-IGA 
 
X 
Xp 
Xp 
Xp 
 
Xp 
 
Xp 
 
Xp 
 
 Xp  
Xp  
Xp  
Xp  
Xp  
Xp 
 
EQ-5D-3L 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
SF-36 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 127 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5, 7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
Patient global 
assessment of 
psoriasisq 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PASE  
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PGADAr 
 
X 
 
 
X 
 
 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
WPAI-SHP V2.0 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Concomitant 
medication 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTs,t 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Bimekizumab, 
adalimumab, or 
placebo 
administrations,t 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Xu X 
X 
X 
X 
X 
X 
X 
 
 
BSA=body surface area; CV=cardiovascular; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case Report Form; eC-SSRS=electronic 
Columbia Suicide Severity Rating Scale; EQ-5D-3L=Euro-Quality of Life 5-Dimensions 3 Levels; GI=gastrointestinal HIV=human immunodeficiency virus; ICF=Informed 
Consent Form; IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; IMP=investigational medicinal product; IRT=interactive response technology; 
PASE=Psoriatic Arthritis Screening and Evaluation; PASI=psoriasis area severity index; PEOT=Premature End of Treatment Visit; PGADA=Patient Global Assessment of 
Disease Activity; PHQ-9=Patient Health Questionnaire-9; PsA=psoriatic arthritis; SF-36=Short Form 36-item Health Survey; SFU=Safety Follow-Up; scalp IGA=scalp-specific 
Investigator’s Global Assessment; TB=tuberculosis; VAS=visual analog scale; WPAI-SHP=Work Productivity and Activity Impairment Questionnaire-specific health problem 
a Visit windows of ±3 days from the first dose at all visits except SFU. The SFU Visit window is -3 and +7 days from last dose. 
b The SFU Visit will occur 20 weeks after the last dose for subjects who do not enroll in the open-label study. 
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Clinical Study Protocol 
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c A separate ICF will be required for subjects who decide to participate in the genomics, genetics, and proteomics substudy. The ICF must be signed prior to 
collecting any samples for the substudy. The samples will be stored at -80°C at the central biorepository for up to 20 years. 
d A separate ICF is required to be completed for the open-label study. 
e Ensure no significant changes in medical history. 
f Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
g The physical examination will include examination of the following systems: eyes, hair, and skin; respiratory; CV; and GI. 
h Vital signs (blood pressures, pulse rate, and temperature) are to be measured prior to blood sampling, and prior to dosing, where applicable. 
i Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
j Subjects who have evidence of or test positive for hepatitis B by any of the following criteria: 1) positive for hepatitis B surface antigen (HBsAg+); 2) positive 
for anti-hepatitis B core antibody (HBcAb+) are excluded. A positive test for HCV is defined as: 1) positive for hepatitis C antibody (anti-HCV Ab), and 
2) positive via a confirmatory test for HCV (for example, HCV polymerase chain reaction) are also excluded  Subjects will also be tested for anti-hepatitis B 
surface antibody. 
k The HIV test results will not be recorded in the eCRF. 
l Screening chest x-ray must occur within 3 months prior to Screening Visit. 
m All blood samples taken prior to dosing. 
n The scalp IGA will only be assessed for those subjects with scalp involvement (scalp IGA score >0) at Baseline. 
o The mNAPSI will be assessed only in subjects with nail involvement (mNAPSI score >0) at Baseline. 
p The pp-IGA will only be assessed in subjects with palmoplantar involvement (pp-IGA score >0) at Baseline. 
q The Patient Global Assessment of psoriasis will be performed as part of the patient symptoms diary on a weekly basis from baselineScreening through the 
Initial Treatment Period with a +3 day completion window. During the Maintenance Treatment Period this assessment will be completed at each clinic visit 
specified with a ±3 day completion window. 
r The PGADA is assessed for all subjects at Baseline. At all subsequent visits, the PGADA is only for subjects with PsA at Baseline (defined as a past 
medical history of PsA or PASE ≥47). 
s IMP administration is based on randomization. 
t For bimekizumab, the minimum time between doses should be no less than 24 days and no more than 32 days. 
u At Week 24 subjects will be re allocated based on original treatment and response to treatment and will receive their first Maintenance Treatment 
Period  
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Bimekizumab 
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Change #16 
Section 5.8.1 Study design 
A randomized, active-controlled study design has been selected to demonstrate efficacy and 
safety of bimkizumab for regulatory approval. The study population will include adults with 
moderate to severe chronic plaque PSO and allow subjects who have received previous biologic 
treatment as well as those who are biologic treatment naïve. The primary efficacy outcome 
measures (based on PASI and IGA) and other efficacy assessments included in this study are 
consistent with those used for other PSO studies and are considered appropriate for establishing 
efficacy of bimekizumab. An initial treatment period of 24 weeks will be used to demonstrate the 
efficacy of bimekizumab compared with adalimumab. The study duration extends beyond the 
initial treatment period (to 56 weeks) to allow for collection of long-term safety and efficacy 
data. 
At Week 24, subjects on adalimumab treatment are re-allocated to treatment with bimekizumab 
320mg Q4W. This allows for a controlled evaluation of the safety and efficacy of switching from 
a product with one mechanism of action to another, which is known to occur in clinical practice 
due to either loss of response or access. In a recent PSO study in which subjects were switched 
from adalimumab to a treatment with a different mechanism of action there was no evidence of 
an increased safety risk following the switch (Reich et al, 2017)  
Has been changed to: 
A randomized, active-controlled study design has been selected to demonstrate efficacy and 
safety of bimkizumab for regulatory approval. The study population will include adults with 
moderate to severe chronic plaque PSO and allow subjects who have received previous biologic 
treatment as well as those who are biologic treatment naïve. The primary efficacy outcome 
measures (based on PASI and IGA) and other efficacy assessments included in this study are 
consistent with those used for other PSO studies and are considered appropriate for establishing 
efficacy of bimekizumab. An initial treatment period of 1624 weeks will be used to demonstrate 
the efficacy of bimekizumab compared with adalimumab. The study duration extends beyond the 
initial treatment period (to 56 weeks) to allow for collection of long-term safety and efficacy 
data. 
At Week 24, subjects on adalimumab treatment are re-allocated to treatment with bimekizumab 
320mg Q4W. This allows for a controlled evaluation of the safety and efficacy of switching from 
a product with one mechanism of action to another, which is known to occur in clinical practice 
due to either loss of response or access. In a recent PSO study in which subjects were switched 
from adalimumab to a treatment with a different mechanism of action, there was no evidence of 
an increased safety risk following the switch without washout (Reich et al, 2017). 
Change #17 
Section 5.8.1 Study design 
The following paragraph has been deleted: 
If subjects do not respond after a switch in treatment or if they lose response over time, the 
mandatory withdrawal criterion for subjects who do not achieve a PASI50 response at Week 36 
or later will ensure that subjects do not continue to receive prolonged exposure to study 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
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Page 132 of 190 
treatment that is providing a sub-optimal response, regardless of their initial randomized 
treatment. 
Change #18 
Section 6.2 
Exclusion criterion #22 
The following criterion has been deleted. 
1. Subject has been exposed to more than 3 biological response modifiers (including no more 
than 1 IL-17). 
Change #19 
Section 6.2 
Exclusion criterion #23 
2. Subject has experienced one primary failure to an IL-17 biological response modifier (no 
response within 12 weeks). 
Has been changed to: 
3. Subject has experienced one primary failure to an IL-17 biological response modifier (no 
response within 12 weeks) to 1 or more IL-17 biologic response modifier (eg, 
brodalumab, ixekizumab, secukinumab) OR more than 1 biologic response modifier 
other than an IL-17. 
Change #20 
Section 6.2 
Exclusion criterion #27 
27. Subject has presence of severe depression, indicated by a score ≥15 using the screening 
PHQ-9. Medication used to treat depression should be stable for 4 weeks prior to baseline. 
Has been changed to: 
27. Subject has presence of severe depression, indicated by a score ≥of 15 to 19 using the 
screening PHQ 9. Medication used to treat depression should be stable for 4 weeks prior to 
Baseline. 
Change #21 
Section 6.3 Withdrawal criterion #2 
2. Moderately severe depression as indicated by a PHQ-9 score ≥15 if this represents an 
increase of 3 points compared to last visit. 
Has been changed to: 
2. Moderately severe depression as indicated by a PHQ-9 score ≥of 15 to 19 if this represents 
an increase of 3 points compared to last visit. 
Change #22 
Section 6.3 
Withdrawal criterion #3  
The following criterion has been deleted: 
Subject does not achieve a PASI50 response at Week 26 or later.` 
 
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Change #23 
Section 7.2 
Treatment(s) to be administered 
Double-blind Initial Treatment Period dosing 
During the Initial Treatment Period, subjects will be randomized 1:1 to receive the following 
blinded study treatment regimens: bimekizumab 320mg or adalimumab. 
Because of differences in the dosing schedule between bimekizumab and adalimumab, all 
subjects will receive 2 injections sc on Weeks 0 (Baseline), 4, 8, 12, 16, and 20, and 1 injection 
sc in other weeks based on the following dosing scheme: 
 Subjects randomized to receive bimekizumab 320mg Q4W will receive 2 bimekizumab 
160mg injections sc Q4W at Weeks 0 (Baseline), 4, 8, 12, 16, and 20. These subjects will 
receive 1 placebo injection at Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23. 
 Subjects randomized to receive adalimumab will receive 2 adalimumab 40mg injections sc at 
Week 0 (Baseline). At Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23 they will receive 1 
adalimumab 40mg injection sc. These subjects will receive 2 placebo injections at Weeks 4, 
8, 12, 16, and 20. 
Maintenance Treatment Period dosing 
Investigational medicinal product treatment during the Maintenance Treatment Period will be 
based on initial treatment and response to treatment at Week 24 as described in Section 5.2.3. 
 Subjects who receive bimekizumab 320mg Q4W will receive 2 bimekizumab 160mg 
injections sc Q4W at Weeks 24, 28, 32, 36, 40, 44, 48, and 52. Note: Subjects initially 
randomized to adalimumab who switch to bimekizumab 320mg Q4W at Week 24 will 
receive their first bimekizumab 320mg dose at Week 24. 
 Subjects who receive bimekizumab 320mg Q8W will receive 2 bimekizumab 160mg 
injections sc Q8W at Weeks 24, 32, 40, and 48. These subjects will receive 2 placebo 
injections at Weeks 28, 36, 44, and 52. 
The dosing scheme is depicted in Table 7-1.
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Bimekizumab 
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Page 134 of 190 
 
Table 7-1: 
Dosing Scheme 
 
Initial Treatment 
Maintenance 
Week 
Dose Assignment 
0 
1,  
3 
4 
5,  
7 
8 
9, 
11 
12 
13, 
15 
16 
17, 
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
bimekizumab 320mg 
Q4W/Q4W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
bimekizumab 320mg 
Q4W/Q8W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
adalimumab 40mg 
▲▲ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
NR=nonresponder; Q4W=every 4 weeks; Q8W=every 8 weeks 
Notes: A bimekizumab 160mg injection is depicted by a black circle (●). A placebo injection is depicted by a white circle (○). An adalimumab 40mg injection is 
depicted by a black triangle (▲). 
Has been changed to:
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Double blind Initial Treatment Period dosing 
During the Initial Treatment Period,Eligible subjects will be randomized 1:1:1 to receive the 
following blinded study treatment regimens: bimekizumab 320mg Q4W throughout the study, 
bimekizumab 320mg Q4W through Week 16, or adalimumab. 
Because of differences in the dosing schedule between bimekizumab and adalimumab and in 
order to maintain blinding, all subjects will receive 2 injections sc on Weeks 0 (Baseline), 4, 8, 
12, 16, and 20, and 24 and 1 injection sc in other weeks based on the following dosing scheme: 
 Subjects randomized to receive bimekizumab 320mg Q4W throughout the study will 
receive 2 bimekizumab 160mg injections sc Q4W at Weeks 0 (Baseline), 4, 8, 12, 16, and 
20, 24, 28, 32, 36, 40, 44, 48, and 52. These subjects will receive 1 placebo injection at 
Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23. 
 Subjects randomized to receive bimekizumab 320mg Q4W/Q8W will receive 2 bimekizumab 
160mg injections sc Q4W at Weeks 0 (Baseline), 4, 8, and 12. Subjects will then receive 
2 bimekizumab 160mg injections sc Q8W at Weeks 16, 24, 32, 40, and 48. These subjects 
will receive 1 placebo injection at Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23 , and 
2 placebo injections at Weeks 20, 28, 36, 44, and 52. 
 Subjects randomized to receive adalimumab will receive 2 adalimumab 40mg injections sc at 
Week 0 (Baseline). At Weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23, they will receive 
1 adalimumab 40mg injection sc. These subjects will receive 2 placebo injections at 
Weeks 4, 8, 12, 16, and 20. These subjects will then receive bimekizumab 320mg Q4W 
given as 2 bimekizumab 160mg injections sc Q4W at Weeks 24, 28, 32, 36, 40, 44, 48, 
and 52. 
Maintenance Treatment Period dosing 
Investigational medicinal product treatment during the Maintenance Treatment Period 
will be based on initial treatment and response to treatment at Week 24 as described in 
Section 5.2.3. 
 Subjects who receive bimekizumab 320mg Q4W will receive 2 bimekizumab 160mg 
injections sc Q4W at Weeks 24, 28, 32, 36, 40, 44, 48, and 52. Note: Subjects initially 
randomized to adalimumab who switch to bimekizumab 320mg Q4W at Week 24 will 
receive their first bimekizumab 320mg dose at Week 24. 
 Subjects who receive bimekizumab 320mg Q8W will receive 2 bimekizumab 160mg 
injections sc Q8W at Weeks 24, 32, 40, and 48. These subjects will receive 2 placebo 
injections at Weeks 28, 36, 44, and 52. 
The dosing scheme is depicted in Table 7-1.
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 136 of 190 
 
Table 7-1: 
Dosing Scheme 
 
Initial Treatment 
Maintenance Treatment 
Week 
Dose Assignment 
0 
1,  
3 
4 
5,  
7 
8 
9, 
11 
12 
13, 
15 
16 
17, 
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
bimekizumab 320mg 
Q4W/Q4W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
bimekizumab 320mg 
Q4W/Q8W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○○ 
○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
adalimumab 40mg 
▲▲ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
NR=nonresponder; Q4W=every 4 weeks; Q8W=every 8 weeks 
Notes: A bimekizumab 160mg injection is depicted by a black circle (●). A placebo injection is depicted by a white circle (○). An adalimumab 40mg injection is 
depicted by a black triangle (▲).
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Change #24 
Section 7.8.1 Permitted concomitant treatments (medications and therapies) 
The following was deleted: 
The following concomitant medications are permitted during the study. 
Change #25 
Table 7-2 
Prohibited psoriasis medications 
Other biologics and other systemic therapies: 
apremilast, tofacitinib  
alefacept, efalizumab, guselkimab 
 
ustekinumab, briakinumab 
rituximab 
 
2 weeks for apremilast and tofacitinib 
3 months for alefacept, efalizumab, and 
guselkimab 
6 months for ustekinumab and briakinumab 
12 months for rituximab 
Anti-IL-17 therapy 
 
3 months 
(bimekizumab is excluded per exclusion 
criteria) 
Has been changed to: 
Other biologics and other systemic therapies: 
apremilast, tofacitinib  
alefacept, efalizumab, guselkumab 
 
ustekinumab, briakinumab 
rituximab 
 
2 weeks for apremilast and tofacitinib 
3 months for alefacept, efalizumab, and 
guselkumab 
6 months for ustekinumab and briakinumab 
12 months for rituximab 
Anti-IL-17 therapy: 
brodalumab 
ixekizumab 
secukinumab 
3 months 
(bimekizumab is excluded per exclusion 
criteria) 
Change #26 
Section 7.10 Randomization and numbering of subjects 
An IRT will be used for assigning eligible subjects to a treatment regimen based on a 
predetermined production randomization and/or packaging schedule provided by UCB (or 
designee). The randomization schedule will be produced by the IRT vendor. The IRT will 
generate individual assignments for subject kits of IMP, as appropriate, according to the visit 
schedule. Subject treatment assignment will be stratified by region and prior biologic exposure 
(yes/no). The IRT will generate individual assignments for subject kits of IMP, as appropriate, 
according to the visit schedule. Efforts should be made to limit the enrollment of subjects with 
prior biologic exposure to approximately 30% of the total study population. 
Has been changed to: 
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An IRT will be used for assigning eligible subjects to a treatment regimen based on a 
predetermined production randomization and/or packaging schedule provided by UCB (or 
designee). The randomization schedule will be produced by the IRT vendor. The IRT will 
generate individual assignments for subject kits of IMP, as appropriate, according to the visit 
schedule. Subject treatment assignment will be stratified by region and prior biologic exposure 
(yes/no). The IRT will generate individual assignments for subject kits of IMP, as appropriate, 
according to the visit schedule. Efforts should be made to limit the enrollment of subjects 
with prior biologic exposure to approximately 30% of the total study population. 
Change #27 
Section 7.10 Randomization and numbering of subjects 
The following sentence has been deleted: 
At Week 24, subjects may be reallocated to a new treatment group based on their PASI response. 
Change #28 
Section 8 Study Procedures by Visit 
The following has been deleted from the bulleted list: 
 The minimum of time between doses should be no less than 21 days and no more than 
35 days. 
Change #29 
Sections 8.1 Screening Visit (2 to 4 weeks), 8.2.1 Baseline Visit, 8.2.2 Week 1 (±3 days), 8.2.3 
Week 3 (±3 days), 8.2.4 Week 4 (±3 days), 8.2.6 Week 8 (±3 days), 8.2.8 Week 12 (±3 days), 
8.2.10 Week 16 (±3 days), 8.3.2 Week 20 (±3 days), 8.3.4 Week 24 (±3 days), 8.3.5 Week 28 
(±3 days), 8.3.6 Week 32 (±3 days), 8.3.7 Week 36 (±3 days), 8.3.8 Week 40 (±3 days), 8.3.9 
Week 44 (±3 days), 8.3.10 Week 48 (±3 days), 8.3.11 Week 52 (±3 days), 8.3.12 Week 56 (±3 
days), and 8.5 Safety Follow-Up Visit (20 weeks after last dose -3/+7 days) 
The following has been added to the bulleted list: 
 Percentage of BSA  
Change #30 
Section 8.1 Screening Visit (2 to 4 weeks) and Section 8.3.4 Week 24 (±3 days) 
The following has been added to the bulleted list: 
 Daily Patient Symptom Diary  
Change #31 
Section 8.2.1 Baseline Visit, Section 8.2.10 Week 16 (±3 days), and Section 8.3.8 Week 40 
(±3 days) 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses  
 Genetic/epigenetic analyses (for subjects participating in the substudy) 
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 PGADA for subjects with PSA at Baseline 
Has been changed to: 
 Obtain blood and urine samples for the following analyses prior to dosing: 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
 Genetic/epigenetic analyses (for participating subjects only participating in the 
substudy) 
 PGADA for subjects with PSA at Baseline 
Change #32 
Section 8.2.1 Baseline Visit 
After completion of the above-mentioned procedures, administration of bimekizumab, 
adalimumab, or placebo will occur. 
Has been changed to: 
After completion of the above-mentioned procedures, administration of bimekizumab, or 
adalimumab, or placebo will occur. 
Change #33 
Section 8.2.2 Week 1 (±3 days) 
 Obtain blood samples for the following analyses prior to dosing: 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses  
Has been changed to: 
 Obtain blood samples for the following analyses prior to dosing: 
 Genomic, proteomic, metabolomics, and candidate biomarker analyses (participating 
subjects only) 
Change #34 
Section 8.2.6 Week 8 (±3 days) 
The following has been deleted from the bulleted list: 
 PGADA for subjects with PsA at Baseline 
Change #35 
Section 8.3.2 Week 16 (±3 days) 
After completion of the above-mentioned procedures, administration of bimekizumab or placebo 
will occur. 
Has been changed to: 
After completion of the above-mentioned procedures, the Maintenance Treatment Period will 
begin with administration of bimekizumab or placebo will occur. 
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Change #36 
The heading for Section 8.3 Dose-blind Maintenance Treatment Period has been moved to 
before Week 17 and 19 (±3 days), and the section was renumbered accordingly 
Change #37 
The following have been added to the bulleted list: 
 Scalp IGA for subjects with scalp involvement at Baseline 
 mNAPSI for subjects with nail involvement at Baseline 
pp-IGA for subjects with palmoplantar involvement at Baseline 
Change #38 
Section 8.3.10 Week 48 (±3 days) 
The following have been deleted from the bulleted list: 
 EQ-5D-3L  
 SF-36  
Change #39 
Section 8.3.11 Week 52 (±3 days) 
The following bullet has been added: 
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB GOLD test be 
performed  
Change #40 
Section 9 Assessment of Efficacy 
The following text has been added: 
The PASI, BSA, IGA, scalp IGA, mNAPSI, and pp-IGA should be performed by the 
Investigator, another delegated physician, or an appropriately qualified medical 
professional (based on local requirements) who has had documented training on how to 
perform these assessments correctly. Preferably the same assessor should evaluate the 
subject at each assessment. 
Change #41 
Section 9.1 Psoriasis Area and Severity Index 
The percent area of involvement (BSA%) is estimated across 4 body areas; head, upper 
extremities, trunk, and lower extremities. Assessors will enter the degree of involvement for a 
given region as a percentage (0-100%) which will then be mapped into a grade on a scale of 0-6 
(0=none; 1=1% to <10% affected, 2=10% to <30% affected, 3=30% to <50% affected, 4=50% to 
<70% affected, 5=70% to <90% affected, 6=90% to 100% affected) (Table 9-1). 
Has been changed to: 
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The percent area of involvement (BSA%) is estimated across 4 body areas; head, upper 
extremities, trunk, and lower extremities. Assessors will enter the degree of involvement for a 
given region as a percentage (0 100%) which will then be mapped into a grade on a scale of 
0 to 6 (0=none; 1=1% to <10% affected, 2=10% to <30% affected, 3=30% to <50% affected, 
4=50% to <70% affected, 5=70% to <90% affected, 6=90% to 100% affected) (Table 9-1). 
Change #42 
Section 9.1 Psoriasis Area and Severity Index 
The total BSA affected by PSO will be derived based on the regional BSA values provided when 
assessing the PASI score. 
Has been changed to: 
The total BSA affected by PSO will be entered as a percentage from 0 to 100derived based 
on the regional BSA values provided when assessing the PASI score. 
Change #43 
Section 9.11 Patient Symptom Diary responses 
UCB developed a new PRO measure that will be used to assess key symptoms relevant to 
patients with moderate to severe chronic plaque PSO. PS0010 used the draft PRO measure in 
selected countries to enable psychometric validation of the PRO. Site staff will train the 
participating subjects on the use of the electronic PRO (ePRO) diary at the Baseline Visit, 
following which the device will be dispensed to the subject for home use until the Week 16 Visit. 
The ePRO diary will be administered on a daily basis from Baseline to the Week 16 Visit. 
Has been changed to: 
UCB developed a new PRO measure that will be used to assess key symptoms relevant to 
patients with moderate to severe chronic plaque PSO. PS0010 used the draft PRO measure in 
selected countries to enable psychometric validation of the PRO. Site staff will train the 
participating subjects on the use of the electronic PRO (ePRO) diary at the ScreeningBaseline 
Visit, following which the device will be dispensed to the subject for home use until the Week 16 
Visit. The ePRO diary will be administered on a daily basis from ScreeningBaseline to the 
Week 16 Visit. 
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Change #44 
Section 12.1.1.4 Other safety topics of interest 
The following paragraph has been deleted: 
The following safety topics are prespecified as being of interest for this study, based on findings 
from the IMP clinical program to date, potential risks generally associated with biologic 
immunomodulators, or findings from other medicines belonging to the same class of drugs. 
There are no specific AE reporting requirements for these topics, however special monitoring, 
additional data collection activities, and/or enhanced signal detection activities (within UCB), are 
in place. 
Change #45 
Section 12.2 Laboratory measurements 
Clinical laboratory assessments consist of serum chemistry, hematology, and urinalysis. A 
centralized laboratory will be used to supply all laboratory test supplies and analyze all blood 
and urine samples for hematology, biochemistry, and urinalysis measurements. Any unscheduled 
laboratory testing should also be collected using the central laboratory. Testing to rule out 
hepatitis B, hepatitis C, and HIV (see Exclusion Criterion #9, Section 6.2) will be performed at 
Screening in addition to those measurements listed in Table 12-2. 
Specific details regarding the handling and processing of serum chemistry, hematology, and 
urinalysis samples are provided in the study laboratory manuals. 
The following laboratory parameters will be measured: 
Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipstick
a 
Basophils 
Calcium 
pH 
Eosinophils 
Chloride 
Albumin (protein) 
Lymphocytes 
Magnesium 
Glucose 
Atypical lymphocytes 
Potassium 
Blood 
Monocytes 
Sodium 
Leukocyte esterase 
Neutrophils 
Glucose 
Nitrite 
Hematocrit 
BUN 
Urine dipstick for pregnancy testing
b 
Hemoglobin 
Creatinine 
 
MCH 
ALP 
 
MCHC 
AST 
 
MCV 
ALT 
 
Platelet count 
GGT 
 
RBC count 
Total bilirubin 
 
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Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipstick
a 
WBC count 
LDH 
 
 
Serum pregnancy testingb 
 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea 
nitrogen; ; GGT=gamma glutamyltransferase; LDH=lactate dehydrogenase; MCH=mean corpuscular hemoglobin; 
MCHC=mean corpuscular hemoglobin concentration; MCV=mean corpuscular volume; RBC=red blood cell; 
WBC=white blood cell 
a A urine microscopic examination will be performed if the result for albumin (protein), leukocyte esterase, blood or 
nitrite is abnormal. A urine microscopic examination will include: WBC, RBC, epithelial cells (squamous, 
transitional and renal tubular), hyaline casts, WBC casts, RBC casts, waxy casts, granular casts, calcium oxalate 
crystals, uric acid crystals, triphosphate crystals, yeast, bacteria, amorphous urates, and amorphous phosphates. 
b Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
Has been changed to: 
Clinical laboratory assessments consist of serum chemistry, hematology, urinalysis, and urine 
drug screen. A centralized laboratory will be used to supply all laboratory test supplies and 
analyze all blood and urine samples for hematology, biochemistry, and urinalysis measurements. 
Any unscheduled laboratory testing should also be collected using the central laboratory. Testing 
to rule out hepatitis B, hepatitis C, and HIV (see Exclusion Criterion #9, Section 6.2) will be 
performed at Screening in addition to those measurements listed in Table 12-2. 
Specific details regarding the handling and processing of serum chemistry, hematology, and 
urinalysis samples are provided in the study laboratory manuals. 
The following laboratory parameters will be measured: 
Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
Basophils 
Calcium 
pH 
Eosinophils 
Chloride 
Albumin (protein) 
Lymphocytes 
Magnesium 
Glucose 
Atypical lymphocytes 
Potassium 
Blood 
Monocytes 
Sodium 
Leukocyte esterase 
Neutrophils 
Glucose 
Nitrite 
Hematocrit 
BUN 
Urine dipstick for pregnancy testingb 
Hemoglobin 
Creatinine 
Urine drug screenc 
MCH 
ALP 
 
MCHC 
AST 
 
MCV 
ALT 
 
Platelet count 
GGT 
 
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Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
RBC count 
Total bilirubin 
 
WBC count 
LDH 
 
 
Serum pregnancy testingb 
 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea 
nitrogen; ; GGT=gamma glutamyltransferase; LDH=lactate dehydrogenase; MCH=mean corpuscular hemoglobin; 
MCHC=mean corpuscular hemoglobin concentration; MCV=mean corpuscular volume; PEOT=Premature End of 
Treatment; RBC=red blood cell; WBC=white blood cell 
a A urine microscopic examination will be performed if the result for albumin (protein), leukocyte esterase, blood or 
nitrite is abnormal. A urine microscopic examination will include: WBC, RBC, epithelial cells (squamous, 
transitional and renal tubular), hyaline casts, WBC casts, RBC casts, waxy casts, granular casts, calcium oxalate 
crystals, uric acid crystals, triphosphate crystals, yeast, bacteria, amorphous urates, and amorphous phosphates. 
b Pregnancy testing will consist of serum testing at the Screening Visit. The pregnancy test will be urine at all other 
visits. 
c Urine drug screen will be performed at Screening Visit and PEOT Visit. 
 
Change #46 
Section 12.3.1 Assessment and management of TB and TB risk factors, Item d 
d. Current or history of NTMB infection despite prior or current therapy. 
Has been changed to: 
d. NTMB infection is defined as a clinical infection caused by mycobacterial species other 
than those belonging to the Mycobacterium tuberculosis complexCurrent or history of 
NTMB infection despite prior or current therapy. 
Change #47 
Section 12.3.1.1 Tuberculosis assessment by IGRA 
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB GOLD is 
recommended) will be performed as described in Table 5-1 for all subjects. The test results will 
be reported as positive, negative, or indeterminate. Positive TB test results must be reported as an 
adverse event and appropriately updated once the final diagnosis is known (e.g. active TB, latent 
TB, or false positive TB test). UCB also recommends that a TB specialist be consulted where TB 
(latent or active) is suspected or if there are doubts regarding test results. If latent or active TB is 
identified, subject must undergo appropriate study-specified withdrawal procedures. The retest 
during Screening must be done during the protocol-defined Screening window. 
Has been changed to: 
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB GOLD is 
recommended) will be performed as described in Table 5-1 for all subjects. The test results will 
be reported as positive, negative, or indeterminate. Positive and indeterminate TB test results 
must be reported as an adverse event and appropriately updated once the final diagnosis is 
known (eg, active TB, latent TB, or false positive TB test). UCB also recommends that a TB 
specialist be consulted where TB (latent or active) is suspected or if there are doubts regarding 
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test results. If latent or active TB is identified, subject must undergo appropriate study-specified 
withdrawal procedures. The retest during Screening must be done during the protocol-defined 
Screening window. 
Change #48 
Section 14.1 Definition of analysis sets 
The following paragraph has been deleted: 
The Maintenance Set (MS) will consist of all subjects who receive at least 1 dose of 
bimekizumab treatment at Week 24 or later. 
Change #49 
Figure 14-1: Sequence of testing 
 
Has been changed to: 
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Change #50 
Section 14.3.1.1 Sensitivity analyses 
In order to obtain reasonable estimates of variability at a given center, a minimum of 10 subjects 
will be considered acceptable for a center to be included in the model without pooling. Given the 
1:1 randomization allocation scheme, this should provide a minimum of about 5 subjects the 
bimekizumab arm and 5 subjects in the adalimumab arm. Centers with fewer than 10 subjects 
will be eligible for pooling. 
The following center pooling algorithm will be used for each geographic region: 
 If a center has 10 or more subjects, then no pooling will be done for that center. 
 Centers with fewer than 10 subjects will be ordered from largest to smallest with pooling 
proceeding in the following manner: 
 Two or more centers will be combined until the cumulative subject total is at least 10. 
 Once a pooled center has at least 10 subjects, the process will continue in an iterative 
fashion for the subsequent centers in the ordered list, where a new pooled center begins 
each time at least 10 subjects has been reached in the previous pool. 
 If this iterative process reaches the end of the ordered list of centers where the final 
pooled center has fewer than 10 subjects, then the subjects from the centers in that pool 
will be combined with the pooled center formed in the previous iteration. 
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Has been changed to: 
In order to obtain reasonable estimates of variability at a given center, a minimum of 150 
subjects will be considered acceptable for a center to be included in the model without pooling. 
Given the 1:1:1 randomization allocation scheme, this should provide a minimum of about 5 
subjects the bimekizumab Q4W arm, 5 subjects in the bimekizumab Q4W/Q8W arm, and 5 
subjects in the adalimumab arm. Centers with fewer than 150 subjects will be eligible for 
pooling. 
The following center pooling algorithm will be used for each geographic region: 
 If a center has 150 or more subjects, then no pooling will be done for that center. 
 Centers with fewer than 150 subjects will be ordered from largest to smallest with pooling 
proceeding in the following manner: 
 Two or more centers will be combined until the cumulative subject total is at least 150. 
 Once a pooled center has at least 150 subjects, the process will continue in an iterative 
fashion for the subsequent centers in the ordered list, where a new pooled center begins 
each time at least 150 subjects has been reached in the previous pool. 
 If this iterative process reaches the end of the ordered list of centers where the final 
pooled center has fewer than 150 subjects, then the subjects from the centers in that pool 
will be combined with the pooled center formed in the previous iteration. 
Change #51 
Section 14.3.2.1.1 Initial Treatment Period 
The secondary efficacy variables for time points during the Initial Treatment Period will be 
analyzed for all subjects in the RS. 
For binary secondary efficacy variables, the stratified CMH test as specified for the primary 
analysis will be implemented to test for superiority of bimekizumab to adalimumab. As in the 
primary analysis, NRI will be used to account for missing data. 
Has been changed to: 
The secondary efficacy variables for time points during the Initial Treatment Period will be 
analyzed for all subjects in the RS. 
For comparisons with adalimumab at Week 16, the 2 bimekizumab arms will be pooled.  
For binary secondary efficacy variables, the stratified CMH test as specified for the primary 
analysis will be implemented to test for superiority of bimekizumab to adalimumab. As in the 
primary analysis, NRI will be used to account for missing data. 
Change #52 
Section 14.3.2.1.2 Maintenance Treatment Period 
The only secondary efficacy variables in the Maintenance Treatment Period are PASI90 and IGA 
at Week 56. 
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Since all subjects on adalimumab will be switched to bimekizumab at Week 24, the assessment 
of PASI90 and IGA at Week 56 will be for bimekizumab at the Q4W and Q8W dosing intervals. 
These summaries will include descriptive statistics by bimekizumab dose regimen for the 
percentage of responders at Week 56 based on the MS. The summary of PASI90 at Week 56 will 
be based on subjects who were PASI90 responders at Week 24 (similarly, the summary of IGA 
responders at Week 56 will be based on Week 24 IGA responders). Subjects with missing data at 
Week 56 or who discontinue study treatment prior to Week 56 will be imputed via NRI. 
Has been changed to: 
The only secondary efficacy variables in the Maintenance Treatment Period includeare PASI90, 
PASI100, and IGA at Week 24 and Week 56. 
Since all subjects on adalimumab will be switched to bimekizumab at Week 24, the assessment 
of PASI90 and IGA at Week 56 will be for bimekizumab at the Q4W and Q8W dosing intervals. 
These summaries will include descriptive statistics by bimekizumab dose regimens for the 
percentage of responders at Week 24 and Week 56 based on the MRS. The summary of 
PASI90 at Week 56 will be based on subjects who were PASI90 responders at Week 24 
(similarly, the summary of IGA responders at Week 56 will be based on Week 24 IGA 
responders). Subjects with missing data at Week 56 or who discontinue study treatment prior to 
Week 56 will be imputed via NRI. 
Change #53 
Section 14.3.2.2 Analysis of other efficacy variables 
The other efficacy variables in the Initial Treatment Period will be analyzed for all subjects in the 
RS. For the Maintenance Treatment Period  summaries will be based on the MS. 
Has been changed to: 
The other efficacy variables in the Initial Treatment Period will be analyzed for all subjects in 
the RS. For the Maintenance Treatment Period, summaries will be based on the MS. 
Change #54 
Section 14.5.1 Safety analyses 
Safety variables will be analyzed for all subjects in the SS. Additional summaries focusing on 
safety during the Maintenance Treatment Period will also be prepared and will be based on the 
MS. 
Adverse events will be coded according to the Medical Dictionary for Regulatory Activities 
(MedDRA). Adverse events will be summarized descriptively by treatment group, primary 
system organ class, High Level Term (HLT), and preferred term. Additional tables will 
summarize AEs by intensity and relationship to IMP, AEs leading to withdrawal from the study, 
SAEs, and deaths. Adverse Events of Special Monitoring will be summarized and will be 
described in greater detail in the SAP. 
Has been changed to: 
Safety variables will be analyzed for all subjects in the SS. Additional summaries focusing on 
safety during the Maintenance Treatment Period will also be prepared and will be based on the 
MRS. 
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Adverse events will be coded according to the Medical Dictionary for Regulatory Activities 
(MedDRA). Adverse events will be summarized descriptively by treatment group, primary 
system organ class, High Level Term (HLT), and preferred term. Additional tables will 
summarize AEs by intensity and relationship to IMP, AEs leading to withdrawal from the study, 
SAEs, and deaths. Adverse Events of Special MonitoringSpecific safety topics of interest will 
be summarized and will be described in greater detail in the SAP. 
 
Change #55 
Section 14.7 Handling of dropouts or missing data 
For the secondary endpoints evaluated at Week 56 (based on the MS), all subjects with missing 
data at Week 56 or who discontinue study treatment prior to Week 56 will be counted as 
nonresponders. 
Has been changed to: 
For the secondary endpoints evaluated at Week 56 (based on the MRS), all subjects with missing 
data at Week 56 or who discontinue study treatment prior to Week 56 will be counted as 
nonresponders. 
Change #56 
Section 14.9 Determination of sample size 
A total of 400 subjects will be randomly assigned in a 1:1 ratio to the following treatment 
groups: 
 Bimekizumab 320mg (200 subjects) 
 Adalimumab (200 subjects) 
When comparing bimekizumab to adalimumab, the assumed responder rates for PASI90 and 
IGA at Week 16 for the bimekizumab group are 75% and 85%, respectively. These estimates are 
based on the results of the Phase 2b PS0010 study. The PASI90 responder rates at Week 16 for 
adalimumab from the VOYAGE-1 and VOYAGE-2 studies were 50% and 47%, respectively 
(Blauvelt et al, 2017; Reich et al, 2017). Additionally, the IGA responder rates at Week 16 for 
adalimumab in VOYAGE-1 and VOYAGE-2 were 66% and 68%, respectively. For the purposes 
of these sample size calculations at Week 16, we assume a PASI90 responder rate and IGA 
responder rate for adalimumab of 50% and 68%, respectively. 
The testing procedure described in Section 14.3 indicates that the first test will be to demonstrate 
noninferiority to adalimumab for the co-primary variables of PASI90 and IGA at Week 16. If 
non-inferiority for both tests is demonstrated, then superiority to adalimumab will be tested. 
Because the superiority evaluation is the more stringent test, sample size calculations are based 
on the testing of superiority to adalimumab for PASI90 and IGA at Week 16. Given these 
assumptions and a sample size of 200 subjects per treatment group,the power to detect a 
statistically significant difference between bimekizumab and adalimumab is >99% for PASI90 
and 97% for IGA. This assumes a 2-sided significance level of 0.05. Because both co-primary 
endpoints are highly powered independently, and because PASI and IGA response tend to be 
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highly correlated, the overall power for achieving superiority on both co-primary endpoints is not 
calculated here as it is similar to the lower of the individual tests. 
Note that the non-inferiority testing procedure will be based on a 1-sided significance level of 
0.025 and a non-inferiority margin of 10%. The power to demonstrate non-inferiority to 
adalimumab using the other assumptions described above is >99% for both PASI90 and IGA 
responses. 
Has been changed to: 
A total of 450400 subjects will be randomly assigned in a 1:1:1 ratio to the following treatment 
groups: 
 Bimekizumab 320mg Q4W throughout the study (150200 subjects) 
 Bimekizumab 320mg Q4W/Q8W (ie, bimekizumab 320mg Q4W through Week 16, then 
bimekizumab 320mg Q8W from Week 16 through Week 52) (150200 subjects) 
 Adalimumab 80mg administered as an initial dose, followed by 40mg Q2W starting 
1 week after the initial dose (ie, adalimumab will be administered according to the 
labeling recommendations) until Week 24, then bimekizumab 320mg Q4W from 
Week 24 to Week 52 (150200 subjects) 
When comparing bimekizumab to adalimumab, the assumed responder rates for PASI90 and 
IGA at Week 16 for the bimekizumab group are 75% and 85%, respectively. These estimates are 
based on the results of the Phase 2b PS0010 study. The PASI90 responder rates at Week 16 for 
adalimumab from the VOYAGE-1 and VOYAGE-2 studies were 50% and 47%, respectively 
(Blauvelt et al, 2017; Reich et al, 2017). Additionally, the IGA responder rates at Week 16 for 
adalimumab in VOYAGE-1 and VOYAGE-2 were 66% and 68%, respectively. For the purposes 
of these sample size calculations at Week 16, we assume a PASI90 responder rate and IGA 
responder rate for adalimumab of 50% and 68%, respectively. 
The testing procedure described in Section 14.3 indicates that the first test will be to demonstrate 
noninferiority to adalimumab for the co-primary variables of PASI90 and IGA at Week 16. If 
non-inferiority for both tests is demonstrated, then superiority to adalimumab will be tested. 
Because the superiority evaluation is the more stringent test, sample size calculations are based 
on the testing of superiority to adalimumab for PASI90 and IGA at Week 16. Given these 
assumptions and a sample size of 150200 subjects per treatment group in the adalimumab 
arm and 300 subjects in the pooled bimekizumab arms, the power to detect a statistically 
significant difference between bimekizumab and adalimumab is >99% for PASI90 response and 
97%  for IGA response. This assumes a 2-sided significance level of 0.05. Because both co-
primary endpoints are highly powered independently, and because PASI and IGA response tend 
to be highly correlated, the overall power for achieving superiority on both co-primary endpoints 
is not calculated here as it is similar to the lower of the individual tests. 
Note that the non-inferiority testing procedure will be based on a 1-sided significance level of 
0.025 and a non-inferiority margin of 10%. The power to demonstrate non-inferiority to 
adalimumab using the other assumptions described above is >99% for both PASI90 and IGA 
responses. 
Change #57 
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Section 17 REFERENCES 
The following references have been deleted from the list: 
Blauvelt A, et al. Level of efficacy and safety of guselkumab, an anti-interleukin-23 monoclonal 
antibody, compared with adalimumab for the continuous treatment of moderate-to-severe 
psoriasis in the phase 3 VOYAGE 1 trial. Annual European Academy of Dermatology and 
Venereology (EADV 2016); 28 Sept–02 Oct, 2016; Vienna, Austria; VIE16LAT-0080. 
Bretz F, Maurer W, Brannath W, Posch M. A graphical approach to sequentially rejective 
multiple test procedure. Statistics in Medicine. 2009;28:586-604. 
Dauden E, Griffiths CE, Ortonne JP, Kragballe K, Molta CT, Robertson D, et al. Improvements 
in patient-reported outcomes in moderate-to-severe psoriasis patients receiving continuous or 
paused etanercept treatment over 54 weeks: the CRYSTEL study. J Eur Acad Dermatol 
Venereol. 2009;23(12):1374-82. 
International Menopause Society. Cornwall, UK: Menopause Terminology; c2015. 
http://www.imsociety.org/menopause_terminology.php. Accessed 05 Dec 2016. 
Langley RG, Feldman SR, Han C, Schenkel B, Szapary P, Hsu MC, et al. Ustekinumab 
significantly improves symptoms of anxiety, depression, and skin-related quality of life in 
patients with moderate-to-severe psoriasis: Results from a randomized, doubleblind, 
placebo-controlled phase III trial. J Am Acad Dermatol. 2010;63(3):457-65. 
Menter A, Tyring SK, Gordon K, Kimball AB, Leonardi CL, Langley RG, et al. Adalimumab 
therapy for moderate to severe psoriasis: A randomized, controlled phase III trial. J Am Acad 
Dermatol 2008;58:106-15. 
Saurat JH, Stingl G, Dubertret L, Papp K, Langley RG, Ortonne JP, et al. Efficacy and safety 
results from the randomized controlled comparative study of adalimumab vs. methotrexate vs. 
placebo in patients with psoriasis (CHAMPION). Brit J Dermatol. 2008;158:558–66. 
18.2 
Protocol Amendment 2 
Rationale for the amendment 
The purpose of this amendment was the following:   
 Extend the duration of the Screening Period, and therefore the overall study duration, by 
1 week 
 Update list of current treatment for PSO to reflect changes in labeling and approved countries 
 Update list of completed and ongoing bimekizumab studies to reflect completion of study 
UP0042 
 Clarify calculation of PASI responder rates 
 Remove references to PD assessments as they will not be conducted in this study 
 Update Schedule of study assessments to include a hematology and biochemistry sample at 
Week 28, and to modify the visits at which the TB questionnaire, body weight, physical 
examination, and ECG are assessed 
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 Clarify that all visits from first dose to Week 24 would have a ±3 day visit window, while all 
visits from Week 28 to end of study would have a ±7 day window 
 Clarify the dosing window 
 Modify exclusion criterion to clarify exclusion of subjects who have participated in other 
studies of bimekizumab, other medications (systemic or topical), or devices 
 Modify exclusion criteria to exclude use of prohibited psoriasis medications 
 Modify exclusion criteria pertaining to history of malignancy, systemic disease, and major 
depression 
 Add new withdrawal criteria for nonresponders and for subjects with newly diagnosed IBD 
 Clarify withdrawal criteria for subjects with depression or suicidal ideation or behavior 
 Correct information pertaining to how adalimumab is supplied 
 Update prohibited concomitant medications to include tildrakizumab and risankizumab 
 Corrected discrepancies between Section 8 Study procedures by visit and Table 5-1 Schedule 
of study assessments 
 Revise PASE questionnaire scoring 
 Clarify definition of abortion 
 Updated laboratory measurements to be performed 
 Provide additional details for requirements for IMP rechallenge in the event of PDILI 
 Defined a BKZ Set as an analysis population 
 Clarify regions for analyses 
 Update the sequence testing and analysis of secondary efficacy variables 
In addition, minor spelling, editorial, and formatting changes were made, and the List of 
abbreviations was updated. 
Change #1 
Section 1 Summary, second and third paragraphs 
The study population consists of adult subjects (≥18 years of age) with a diagnosis of moderate 
to severe chronic plaque PSO (Baseline Psoriasis Area and Severity Index [PASI] ≥12 and body 
surface area [BSA] affected by PSO ≥10% and Investigator’s Global Assessment [IGA] score ≥3 
[on a 5-point scale]) who are candidates for adalimumab or for systemic PSO therapy and/or 
phototherapy and/or photochemotherapy. 
Approximately 600 subjects will be screened in order to have a total of 450 subjects randomized 
in the study. For each subject, the study will last a maximum of 76 weeks and will consist of 
4 periods, a Screening Period (2 to 4 weeks), a double-blind, active comparator-controlled Initial 
Treatment Period (16 weeks), a dose-blind Maintenance Treatment Period (40 weeks), and a 
Safety Follow-Up (SFU) Period (20 weeks after the last dose of the investigational medicinal 
product [IMP]).  
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Has been changed to:  
The study population consists of adult subjects (≥18 years of age) with a diagnosis of moderate 
to severe chronic plaque PSO (Baseline Psoriasis Area and Severity Index [PASI] ≥12 and body 
surface area [BSA] affected by PSO ≥10% and Investigator’s Global Assessment [IGA] score ≥3 
[on a 5-point scale]) who are candidates for adalimumab or for systemic PSO therapy and/or 
phototherapy and/or photochemotherapy. 
Approximately 600 subjects will be screened in order to have a total of 450 subjects randomized 
in the study. For each subject, the study will last a maximum of 76 77 weeks and will consist of 
4 periods, a Screening Period (2 to 4 5 weeks), a double-blind, active comparator-controlled 
Initial Treatment Period (16 weeks), a dose-blind Maintenance Treatment Period (40 weeks), and 
a Safety Follow-Up (SFU) Period (20 weeks after the last final dose of the investigational 
medicinal product [IMP]).  
Change #2 
Section 2.1.2 Current treatments for psoriasis, 1st paragraph 
Therapy for patients with PSO varies according to the severity of disease. Limited or mild 
disease is often treated with topical therapies such as corticosteroids and vitamin D analogs. 
Patients with more severe disease are often treated with photochemotherapy, methotrexate, 
cyclosporine, the oral phosphodiesterase 4 (PDE4) inhibitor apremilast, or biologic agents, such 
as tumor necrosis factor (TNF) antagonists, interleukin (IL)-12/23 inhibitors, IL-23p19 inhibitors 
and IL-17A inhibitors. The effectiveness of TNF inhibitors in the treatment of PSO has been 
demonstrated in many Phase 3 clinical studies and has led to the approval of multiple TNF 
inhibitors for use in patients with moderate to severe PSO. Interleukin inhibitors approved for 
this indication include the IL-12/23 antagonist ustekinumab, the IL-23p19 antagonist 
guselkumab (in the US only) the IL-17A inhibitors secukinumab and ixekizumab, and the 
IL-17 receptor antagonist brodalumab.  
Has been changed to:  
Therapy for patients with PSO varies according to the severity of disease. Limited or mild 
disease is often treated with topical therapies such as corticosteroids and vitamin D analogs. 
Patients with more severe disease are often treated with photochemotherapy phototherapy, 
methotrexate, cyclosporine, the oral phosphodiesterase 4 (PDE4) inhibitor apremilast, or biologic 
agents, such as tumor necrosis factor (TNF) antagonists, interleukin (IL)-12/23 inhibitors, IL-
23p19 inhibitors and IL-17A inhibitors. The effectiveness of TNF inhibitors in the treatment of 
PSO has been demonstrated in many Phase 3 clinical studies and has led to the approval of 
multiple TNF inhibitors for use in patients with moderate to severe PSO. Interleukin inhibitors 
approved for this indication include the IL-12/23 antagonist ustekinumab, the IL-23p19 
antagonist guselkumab (in the US only), the IL-17A inhibitors secukinumab and ixekizumab, 
and the IL-17 receptor antagonist brodalumab.  
Change #3 
Section 2.1.2 Current treatments for psoriasis, third bullet 
 Chemophototherapy is a frequent option for moderate to severe patients, but the 
inconvenience of multiple treatment visits and varying efficacy limits its use in the market. 
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Has been changed to:  
 Phototherapy Chemophototherapy is a frequent option for moderate to severe patients, but 
the inconvenience of multiple treatment visits and varying efficacy limits its use in the 
market. 
Change #4 
Section 2.1.2 Current treatments for psoriasis, last bullet, second and fourth sub-bullets 
 Ustekinumab has been approved in the US and the EU for the treatment of adult patients 
with moderate to severe plaque PSO who are candidates for phototherapy or systemic 
therapy. Ustekinumab is a human immunoglobulin (Ig) G1κ monoclonal antibody that 
binds with specificity to the p40 protein subunit used by both the IL-12 and IL-23 
cytokines, naturally occurring cytokines that are involved in inflammatory and immune 
responses, such as natural killer cell activation and CD4+ T-cell differentiation and 
activation.  
 Guselkumab has been approved in the US for the treatment of adult patients with 
moderate to severe plaque PSO who are candidates for systemic therapy or phototherapy. 
It is a human monoclonal IgG1λ antibody that selectively binds to the p19 subunit of 
interleukin 23 (IL-23) and inhibits its interaction with the IL-23 receptor. IL-23 is a 
naturally occurring cytokine that is involved in normal inflammatory and immune 
responses. Guselkumab inhibits the release of proinflammatory cytokines and 
chemokines. 
Has been changed to:  
 Ustekinumab has been approved in the US and the EU for the treatment of adult patients 
with moderate to severe plaque PSO who are candidates for phototherapy or systemic 
therapy. Ustekinumab is a human immunoglobulin (Ig) G1κ monoclonal antibody that 
binds with specificity to the p40 protein subunit used by both the IL-12 and IL-23 
cytokines, naturally occurring cytokines that are involved in inflammatory and immune 
responses, such as natural killer cell activation and CD4+ T-cell differentiation and 
activation.  
 Guselkumab has been approved in the US and the EU for the treatment of adult patients 
with moderate to severe plaque PSO who are candidates for systemic therapy or 
phototherapy. It is a human monoclonal IgG1λ antibody that selectively binds to the p19 
subunit of interleukin 23 (IL-23) and inhibits its interaction with the IL-23 receptor. 
IL-23 is a naturally occurring cytokine that is involved in normal inflammatory and 
immune responses. Guselkumab inhibits the release of proinflammatory cytokines and 
chemokines. 
Change #5 
Section 2.2.1.1 Completed studies 
Four clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with mild to 
moderate plaque PSO, RA0124 in 30 healthy volunteers, PA0007 in 53 subjects with PsA, and 
UP0031 in 12 healthy volunteers.  
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Has been changed to: 
Four Five clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with 
mild to moderate plaque PSO, RA0124 in 30 healthy volunteers, PA0007 in 53 subjects with 
PsA, and UP0031 in 12 healthy volunteers, and UP0042 in 48 healthy volunteers.  
And the following paragraph has been added: 
UP0042 was a randomized double-blind, placebo-controlled, single-dose, parallel-group 
study to evaluate the safety, tolerability, and pharmacokinetics of bimekizumab 
administered as subcutaneous injection to Japanese and Caucasian healthy subjects. This 
study demonstrated that the PK profiles following single administration of 80mg, 160mg, 
and 320mg with sc injection were dose proportional with a linear elimination in both 
Japanese and Caucasian subjects and that the PK profiles of Japanese and Caucasian 
subjects were considered to be generally similar. A single dose of bimekizumab (80mg, 
160mg, or 320mg) administered as sc injection was generally safe and well tolerated in 
healthy Japanese and Caucasian subjects and no major differences in safety findings were 
observed between Japanese and Caucasian subjects. 
Change #6 
Section 2.2.1.2 Ongoing studies 
Four additional studies of bimekizumab in the treatment of PSO and 1 study in healthy 
volunteers are ongoing.  
 PS0010 is a Phase 2b, double-blind, placebo-controlled, dose ranging study to evaluate the 
safety, efficacy, PK, and pharmacodynamics (PD) of bimekizumab in adult subjects with 
moderate to severe chronic plaque PSO. 
 PS0011 is a long-term extension study for subjects who completed PS0010 to assess the 
long-term safety, tolerability, and efficacy of bimekizumab. 
 PS0016 is a Phase 2a, subject-blind, Investigator-blind study to evaluate the time course of 
PD response, safety, and PK of bimekizumab in adult subjects with moderate to severe 
chronic plaque PSO. 
 PS0018 is a long-term extension study for eligible subjects from PS0016 to assess the safety, 
tolerability, and efficacy of bimekizumab. 
 UP0042 is a Phase 1 study designed to evaluate the safety, tolerability, and PK of 
bimekizumab administered as an sc injection of 80mg, 160mg, or 320mg to Japanese and 
Caucasian healthy subjects. 
Has been changed to:  
Four additional studies of bimekizumab in the treatment of PSO and 1 study in healthy 
volunteers are ongoing.  
 PS0010 is a Phase 2b, double-blind, placebo-controlled, dose ranging study to evaluate the 
safety, efficacy, PK, and pharmacodynamics (PD) of bimekizumab in adult subjects with 
moderate to severe chronic plaque PSO. 
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 PS0011 is a long-term extension study for subjects who completed PS0010 to assess the 
long-term safety, tolerability, and efficacy of bimekizumab. 
 PS0016 is a Phase 2a, subject-blind, Investigator-blind study to evaluate the time course of 
PD response, safety, and PK of bimekizumab in adult subjects with moderate to severe 
chronic plaque PSO. 
 PS0018 is a long-term extension study for eligible subjects from PS0016 to assess the safety, 
tolerability, and efficacy of bimekizumab. 
 UP0042 is a Phase 1 study designed to evaluate the safety, tolerability, and PK of 
bimekizumab administered as an sc injection of 80mg, 160mg, or 320mg to Japanese 
and Caucasian healthy subjects. 
Change #7 
Section 4.3 Other variables 
The following text has been added: 
The other variables are listed below and will be evaluated according to the planned 
assessments Table 5-1. 
Change #8 
Section 4.3.1 Other efficacy variables, last sentence in second paragraph 
Note that PASI responder rates will always be calculated relative to the Baseline (first dose) 
Visit. 
Has been changed to:  
Note that Unless otherwise stated PASI responder rates will always be calculated relative to 
the Baseline (first dose) Visit. 
Change #9 
Section 4.4 Pharmacokinetic variable 
Section 4.5 Pharmacogenomic variables 
Section 4.6 Immunological variable 
Have been changed to:  
Section 4.4 4.3.3 Pharmacokinetic variable 
Section 4.5 4.3.4 Pharmacogenomic variables 
Section 4.6 4.3.5 Immunological variable 
Change #10 
Section 5.1 Study description 
PS0008 is a Phase 3, multicenter study consisting of a 16-week, randomized, double-blind, 
parallel-group, active-comparator-controlled Initial Treatment Period followed by a 40-week, 
Maintenance Treatment Period to evaluate the efficacy and safety of bimekizumab in adult 
subjects with moderate to severe chronic plaque PSO. To be eligible to participate in this study, 
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subjects must be adults with a diagnosis of moderate to severe PSO (Baseline PASI ≥12 and 
BSA affected by PSO ≥10% and IGA score ≥3 [on a 5-point scale]) who are candidates for 
systemic PSO therapy and/or phototherapy and/or photochemotherapy. Adalimumab will be 
administered per the local label. Up to 30% of subjects may have been previously exposed to a 
biologic therapy (see Exclusion Criterion #23, Section 6.2). 
Has been changed to:  
PS0008 is a Phase 3, multicenter study consisting of a 16-week, randomized, double-blind, 
parallel-group, active-comparator-controlled Initial Treatment Period followed by a 40-week, 
Maintenance Treatment Period to evaluate the efficacy and safety of bimekizumab in adult 
subjects with moderate to severe chronic plaque PSO. To be eligible to participate in this study, 
subjects must be adults with a diagnosis of moderate to severe PSO (Baseline PASI ≥12 and 
BSA affected by PSO ≥10% and IGA score ≥3 [on a 5-point scale]) who are candidates for 
systemic PSO therapy and/or phototherapy and/or photochemotherapy. Adalimumab will be 
administered per the local label. Up to 30% of subjects may have been previously exposed to a 
biologic therapy (see Exclusion Criterion #23, Section 6.2). 
Change #11 
Section 5.2 
Study periods 
This study will include 4 periods, a Screening Period (2 to 4 weeks), an Initial Treatment Period 
(16 weeks), a Maintenance Treatment Period (40 weeks), and a SFU Period (20 weeks after the 
last dose of IMP). 
Has been changed to:  
This study will include 4 periods, a Screening Period (2 to 4 5 weeks), an Initial Treatment 
Period (16 weeks), a Maintenance Treatment Period (40 weeks), and a SFU Period (20 weeks 
after the last final dose of IMP). 
Change #12 
Section 5.2.1 Screening Period 
The Screening Period will last 2 weeks, but can be extended up to a total of 4 weeks. 
Has been changed to:  
The Screening Period will last 2 weeks, but can be extended up to a total of 4 5 weeks in cases 
where a laboratory assessment needs to be repeated or to allow washout of prohibited 
medications. 
 
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Change #13 
Section 5.3 Study duration per subject 
For each subject, the study will last a maximum of up to 76 weeks, as follows: 
 Screening Period: 2 to 4 weeks 
Has been changed to:  
For each subject, the study will last a maximum of up to 76 77 weeks, as follows: 
 Screening Period: 2 to 4 5 weeks 
Change #14 
Section 5.5 Anticipated regions and countries 
 The regions planned for study conduct are Europe, Canada, and the US, with possible 
extension to other regions and countries.   
Has been changed to:  
The regions planned for study conduct are North America, Western Europe, Canada, and the 
US Central/Eastern Europe, and Asia/Australia, with possible extension to other regions and 
countries. 
Change #15 
Section 5.6 Schedule of study assessments  
The schedule of study assessments for all subjects enrolled in the study is presented in Table 5-1. 
Has been changed to: 
The schedule of study assessments for all subjects enrolled in the study is presented in Table 5-1. 
At each visit, all study assessments should be performed prior to administration of IMP. 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Informed consentc 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Xd  
 
Inclusion/exclusion 
X X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
Demographic data 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Psoriasis history 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Significant past 
medical history and 
concomitant 
diseases 
X Xe 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical 
examinationf,g 
X  
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Vital signsh 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and 
biochemistry 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
Urinalysis 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
ECG 
X  
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Pregnancy testingi 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Hepatitis B and C 
testingj 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV testingk 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest x-rayl 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IGRA Tuberculosis 
test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
Tuberculosis 
questionnaire 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
X 
 
X 
X 
X 
Blood sample for 
bimekizumab 
plasma 
concentrationsm 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
anti-bimekizumab 
antibodiesm 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample 
genomic, 
proteomic, and 
metabolomics, and 
candidate 
biomarker 
analysesc,m 
 
X 
X 
 
 
 
X 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Blood sample 
genetic/epigenetic 
analysesc,m 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PASI  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Percentage of BSA 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PHQ-9 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
eC-SSRS 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Patient Symptom 
Diary (daily)  
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
scalp IGA 
 
X 
Xn 
Xn 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn  
Xn  
Xn  
Xn  
Xn 
 
mNAPSI 
 
X 
 
 
Xo 
 
Xo 
 
Xo 
 
Xo 
 
 Xo 
 
Xo  
Xo  
Xo  
Xo  
Xo 
 
pp-IGA 
 
X 
 
 
Xp 
 
Xp 
 
Xp 
 
Xp 
 
 Xp 
 
Xp  
Xp  
Xp  
Xp  
Xp 
 
EQ-5D-3L 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
SF-36 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Patient global 
assessment of 
psoriasisq 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
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Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
PASE  
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PGADAr 
 
X 
 
 
X 
 
 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
WPAI-SHP V2.0 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Concomitant 
medication 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTs 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Bimekizumab, 
adalimumab, or 
placebo 
administrations 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
BSA=Body Surface Area; CV=cardiovascular; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case Report Form; eC-SSRS=electronic 
Columbia Suicide Severity Rating Scale; EQ-5D-3L=Euro-Quality of Life 5-Dimensions 3 Levels; GI=gastrointestinal; HCV=hepatitis C virus; HIV=human immunodeficiency 
virus; ICF=Informed Consent Form; IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; IMP=investigational medicinal product; IRT=interactive 
response technology; mNAPSI=Modified Nail Psoriasis Severity Index Score; PASE=Psoriatic Arthritis Screening and Evaluation; PASI=psoriasis area severity index; 
PD=pharmacodynamic; PEOT=Premature End of Treatment Visit; PGADA=Patient Global Assessment of Disease Activity; PHQ-9=Patient Health Questionnaire-9; 
pp-IGA=palmoplantar Investigator’s Global Assessment; PsA=psoriatic arthritis; SF-36=Short Form 36-item Health Survey; SFU=Safety Follow-Up; scalp IGA=scalp-specific 
Investigator’s Global Assessment; TB=tuberculosis; WPAI-SHP=Work Productivity and Activity Impairment Questionnaire-specific health problem 
a Visit windows of ±3 days from the first dose at all visits except SFU. The SFU Visit window is -3 and +7 days from last dose. 
b The SFU Visit will occur 20 weeks after the last dose for subjects who do not enroll in the open-label study. 
c A separate ICF will be required for subjects who decide to participate in the genomics, genetics, and proteomics substudy. The ICF must be signed prior to 
collecting any samples for the substudy. The samples will be stored at -80°C at the central biorepository for up to 20 years. 
d A separate ICF is required to be completed for the open-label study. 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 163 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
e Ensure no significant changes in medical history. 
f Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
g The physical examination will include examination of the following systems: eyes, hair,and skin; respiratory; CV; and GI. 
h Vital signs (sitting systolic and diastolic blood pressure, pulse rate, and body temperature) are to be measured prior to blood sampling, and prior to dosing, 
where applicable. 
i Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
j Subjects who have evidence of or test positive for hepatitis B by any of the following criteria: 1) positive for hepatitis B surface antigen (HBsAg+); 2) positive 
for anti-hepatitis B core antibody (HBcAb+) are excluded. A positive test for HCV is defined as: 1) positive for hepatitis C antibody (anti-HCV Ab), and 
2) positive via a confirmatory test for HCV (for example, HCV polymerase chain reaction) are also excluded. Subjects will also be tested for anti-hepatitis B 
surface antibody. 
k The HIV test results will not be recorded in the eCRF. 
l Screening chest x-ray must occur within 3 months prior to Screening Visit. 
m All blood samples taken prior to dosing. 
n The scalp IGA will only be assessed for those subjects with scalp involvement (scalp IGA score >0) at Baseline. 
o The mNAPSI will be assessed only in subjects with nail involvement (mNAPSI score >0) at Baseline. 
p The pp-IGA will only be assessed in subjects with palmoplantar involvement (pp-IGA score >0) at Baseline. 
q The Patient Global Assessment of psoriasis will be performed as part of the patient symptoms diary on a weekly basis from Screening through the Initial 
Treatment Period with a +3 day completion window. During the Maintenance Treatment Period this assessment will be completed at each clinic visit specified 
with a ±3 day completion window. 
r The PGADA is assessed for all subjects at Baseline. At all subsequent visits, the PGADA is only for subjects with PsA at Baseline (defined as a past medical 
history of PsA or PASE ≥47). 
s IMP administration is based on randomization.  
 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 164 of 190 
Has been changed to:  
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Informed consentc 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Xd  
 
Inclusion/exclusion 
X X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
Demographic data 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Psoriasis history 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Significant past 
medical history and 
concomitant 
diseases 
X Xe 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical 
examinationf,g 
X X 
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
Vital signsh 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and 
biochemistry 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
 
X 
 
X 
 
X 
X 
Urinalysis 
X X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
ECG 
X  
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
 
X 
 
X 
 
REDACTED COPY 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 165 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Pregnancy testingi 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hepatitis B and C 
testingj 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV testingk 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest x-rayl 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IGRA Tuberculosis 
test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
Tuberculosis 
questionnaire 
X X 
 
 
 
 
 
 
X 
 
X 
 
 
 
X 
 
 
X 
 
X 
X 
X 
X 
X 
Blood sample for 
bimekizumab 
plasma 
concentrationsm 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample for 
anti-bimekizumab 
antibodiesm 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
X 
 
 
X 
 
X 
X 
Blood sample 
genomic, 
proteomic, and 
metabolomics, and 
candidate 
biomarker 
analysesc,m 
 
X 
X 
 
 
 
X 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
 
 
X 
 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 166 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
Blood sample 
genetic/epigenetic 
analysesc,m 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PASI  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA  
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Percentage of BSA 
X X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
PHQ-9 
X X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
eC-SSRS 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Patient Symptom 
Diary (daily)  
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
scalp IGA 
 
X 
Xn 
Xn 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn 
 
Xn  
Xn  
Xn  
Xn  
Xn 
 
mNAPSI 
 
X 
 
 
Xo 
 
Xo 
 
Xo 
 
Xo 
 
 Xo 
 
Xo  
Xo  
Xo  
Xo  
Xo 
 
pp-IGA 
 
X 
 
 
Xp 
 
Xp 
 
Xp 
 
Xp 
 
 Xp 
 
Xp  
Xp  
Xp  
Xp  
Xp 
 
EQ-5D-3L 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
SF-36 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Patient global 
assessment of 
psoriasisq 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 167 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
PASE  
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
PGADAr 
 
X 
 
 
X 
 
 
 
X 
 
X 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
WPAI-SHP V2.0 
 
X 
 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
X 
 
Concomitant 
medication 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTs 
X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Bimekizumab, 
adalimumab, or 
placebo 
administrations 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
BSA=Body Surface Area; CV=cardiovascular; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case Report Form; eC-SSRS=electronic 
Columbia Suicide Severity Rating Scale; EQ-5D-3L=Euro-Quality of Life 5-Dimensions 3 Levels; GI=gastrointestinal; HCV=hepatitis C virus; HIV=human immunodeficiency 
virus; ICF=Informed Consent Form; IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; IMP=investigational medicinal product; IRT=interactive 
response technology; mNAPSI=Modified Nail Psoriasis Severity Index Score; PASE=Psoriatic Arthritis Screening and Evaluation; PASI=psoriasis area severity index; 
PD=pharmacodynamic; PEOT=Premature End of Treatment Visit; PGADA=Patient Global Assessment of Disease Activity; PHQ-9=Patient Health Questionnaire-9; 
pp-IGA=palmoplantar Investigator’s Global Assessment; PsA=psoriatic arthritis; SF-36=Short Form 36-item Health Survey; SFU=Safety Follow-Up; scalp IGA=scalp-specific 
Investigator’s Global Assessment; TB=tuberculosis; WPAI-SHP=Work Productivity and Activity Impairment Questionnaire-specific health problem 
a Visit windows of ±3 days from the first dose at all visits except SFU. Visit windows of ±3 days from the first dose to the Week 24 visit. Visit windows of 
±7 days from the Week 28 visit to the Week 52 visit. The SFU Visit window is 3 and +7 days ±7 days from last final dose. 
b The SFU Visit will occur 20 weeks after the last final dose for subjects who do not enroll in the open-label study. 
c A separate ICF will be required for subjects who decide to participate in the genomics, genetics, and proteomics substudy. The ICF must be signed 
prior to collecting any samples for the substudy. All genomic, proteomic, and metabolomics samples will be stored at -80°C at the central biorepository 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 168 of 190 
Table 5-1: 
Schedule of study assessments 
Visita / 
Week 
Screening 
Double-blind Initial Treatment Period 
(weeks after first dose) 
 
Dose-blind Maintenance Treatment Period 
(weeks after first dose) 
W56/PEOT 
SFUb 
Protocol activity 
 
Baseline 
(first dose) 
1 
3 
4 
5,  
7 
8 
9, 
11 
12 
13,
15 
16 
17,
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
56 
 
for up to 20 years. 
d A separate ICF is required to be completed for the open-label study. 
e Ensure no significant changes in medical history. 
f Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
g The physical examination will include examination of the following systems: eyes, hair,and skin; respiratory; CV; and GI be performed as per Section 12.3.5 . 
h Vital signs (sitting systolic and diastolic blood pressure, pulse rate, and body temperature) are to be measured prior to blood sampling, and prior to dosing, 
where applicable. 
i Pregnancy testing will consist of serum testing at the Screening. The pregnancy test will be urine at all other visits. 
j Subjects who have evidence of or test positive for hepatitis B by any of the following criteria: 1) positive for hepatitis B surface antigen (HBsAg+); 2) positive 
for anti-hepatitis B core antibody (HBcAb+) are excluded. A positive test for HCV is defined as: 1) positive for hepatitis C antibody (anti-HCV Ab), and 
2) positive via a confirmatory test for HCV (for example, HCV polymerase chain reaction) are also excluded. Subjects will also be tested for anti-hepatitis B 
surface antibody. 
k The HIV test results will not be recorded in the eCRF. 
l Screening chest x-ray must occur within 3 months prior to Screening Visit. 
m All blood samples taken prior to dosing. 
n The scalp IGA will only be assessed for those subjects with scalp involvement (scalp IGA score >0) at Baseline. 
o The mNAPSI will be assessed only in subjects with nail involvement (mNAPSI score >0) at Baseline. 
p The pp-IGA will only be assessed in subjects with palmoplantar involvement (pp-IGA score >0) at Baseline. 
q The Patient Global Assessment of psoriasis will be performed as part of the patient symptoms diary on a weekly basis from Screening through the Initial 
Treatment Period with a +3 day completion window at the specified clinic visits. During the Maintenance Treatment Period this assessment will be 
completed at each clinic visit specified with a ±3 day completion window at the specified clinic visits. 
r The PGADA is assessed for all subjects at Baseline. At all subsequent visits, the PGADA is only for subjects with PsA at Baseline (defined as a past medical 
history of PsA or PASE ≥47). 
s IMP administration is based on randomization. The dosing window is ±3 days relative to the scheduled dosing visit through Week 24. The dosing window 
is ±7 days from Week 28 through the end of the study. 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 169 of 190 
Change #16 
Section 5.7 Schematic diagram 
The following footnote was added after Figure 5-1 Schematic diagram of PS0008:  
Note: At Week 28 and all following visits, subjects on continuous treatment with the same 
IMP for at least 12 weeks with a persistent IGA score ≥3 over at least a 4-week period 
are defined as nonresponders and should discontinue IMP. 
Change #17 
Section 6.1 
Inclusion criteria 
To be eligible to participate in this study, all of the following criteria must be met at Screening 
and be reconfirmed at the Baseline Visit: 
6. Subject is a candidate for systemic PSO therapy and/or phototherapy and/or 
photochemotherapy. 
Have been changed to: 
To be eligible to participate in this study, all of the following criteria must be met at Screening 
and be reconfirmed at the Baseline Visit: 
6a. Subject is a candidate for systemic PSO therapy and/or phototherapy and/or 
photochemotherapy. 
Change #18 
Section 6.2 
Exclusion criteria 
3. Subject previously participated in another study of a medication (systemic) under investigation 
within the 12 weeks or at least 5 half-lives prior to the Screening Visit, whichever is greater, 
or is currently participating in another study of a medication (systemic) under investigation. 
4. Subject previously participated in another study of a topical medication under investigation 
within the 4 weeks prior to the Screening Visit, or is currently participating in another study of 
a topical medication under investigation. 
5. Subject previously participated in another study of a medical device under investigation 
within the 4 weeks prior to the Screening Visit, or is currently participating in another study of 
a medical device under investigation. 
14. Subject has any active malignancy or history of malignancy within 5 years prior to the 
Screening Visit EXCEPT treated and considered cured cutaneous squamous or basal cell 
carcinoma, or in situ cervical cancer, or ductal carcinoma in situ of the breast. 
17. Subject has any systemic disease (eg, renal failure, heart failure, hypertension, liver disease, 
diabetes) considered by the Investigator to be uncontrolled, unstable, or likely to progress to 
a clinically significant degree during the course of the study. 
27. Subject has presence of severe depression, indicated by a score of 15 to 19 using the 
screening PHQ-9. Medication used to treat depression should be stable for 4 weeks prior to 
Baseline. 
Have been changed to: 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
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Page 170 of 190 
3a. Subject previously participated in another study of a medication (systemic) under 
investigation within the 12 weeks or at least 5 half lives prior to the Screening Visit, 
whichever is greater, or is currently participating in another study of a medication 
(systemic) under investigation. Subject must be washed out of the medication for 12 
weeks or at least 5 half-lives prior to the Baseline Visit, whichever is greater. 
4a. Subject previously participated in another study of a topical medication under 
investigation within the 4 weeks prior to the Screening Visit, or is currently participating 
in another study of a topical medication under investigation. Subject must be washed out of 
the medication for 4 weeks prior to the Baseline Visit. 
5a. Subject previously participated in another study of a medical device under investigation 
within the 4 weeks prior to the Screening Visit, or is currently, or was within the 4 weeks 
prior to the Baseline Visit, participating in another study of a medical device under 
investigation. 
14a. 
Subject has any active malignancy or history of malignancy within 5 years prior to the 
Screening Visit EXCEPT treated and considered cured cutaneous squamous or basal cell 
carcinoma, or in situ cervical cancer, or ductal carcinoma in situ of the breast. 
17a. 
Subject has any systemic disease (eg, renal failure, heart failure, hypertension, liver 
disease, diabetes ie, cardiovascular, neurological, renal, liver, metabolic, gastrointestinal, 
hematological, immunological, etc.) considered by the Investigator to be uncontrolled, 
unstable, or likely to progress to a clinically significant degree during the course of the study. 
27a. 
Subject has presence of moderately severe major depression or severe major 
depression, indicated by a score of ≥15 using the screening PHQ-9. Medication used to treat 
depression should be stable for 4-8 weeks prior to Baseline. 
Change #19 
Section 6.2 
Exclusion criteria 
The following text has been added: 
30. 
Subject is taking or has taken prohibited psoriasis medications without meeting the 
mandatory washout period relative to the Baseline Visit (Table 7‒2). 
Change #20 
Section 6.3 Withdrawal criteria  
The following withdrawal criteria have been added, modified, and/or renumbered: 
8. 
At Week 28 and all following visits, subjects on continuous treatment with the same 
IMP for at least 12 weeks with a persistent IGA score ≥3 over at least a 4-week 
period are defined as nonresponders and should discontinue IMP. 
9.  There is confirmation of a pregnancy during the study, as evidenced by a positive pregnancy 
test (see Section 12.1.4 for more information regarding pregnancies). 
10. A subject considered as having either a suspected new LTB infection or who develops active 
TB or NTMB infection during the study (including but not limited to, conversion 
demonstrated by IGRA or other diagnostic means) must be immediately discontinued from 
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Clinical Study Protocol 
Bimekizumab 
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IMP and a PEOT Visit must be scheduled as soon as possible, but not later than the next 
regular visit. 
The subject must be permanently withdrawn if further examinations result in a diagnosis of 
active TB, or if the subject is diagnosed with latent TB infection (LTBI) with no initiation of 
prophylactic treatment, prematurely discontinues prophylactic treatment, or, in the opinion of the 
Investigator or Sponsor, is noncompliant with prophylactic TB therapy. 
Confirmed active TB is an SAE and must be captured on an SAE Report Form and provided to 
the Sponsor in accordance with SAE reporting requirements. As with all SAEs, periodic follow-
up reports should be completed as per protocol requirements until such time as the TB infection 
resolves. 
Additional information on TB policies is provided in Section 12.3.1. 
11.  
Subjects with newly diagnosed inflammatory bowel disease (IBD) or with IBD flares 
during the study must: 
 Be referred, as appropriate, to a health care professional treating IBD, such as a 
gastroenterologist 
 Discontinue IMP and be followed-up until resolution of active IBD symptoms 
If IBD flares increase in severity or frequency during the study, the Investigator should use 
clinical judgement in deciding whether the subject should continue in the study and contact 
the Medical Monitor and UCB study physician to confirm the subject’s suitability for 
continued participation in the study. 
12. Subjects must be referred immediately to a mental health care professional and may be 
withdrawn from the study based upon the Investigator’s judgment of benefit/risk for either 
of the following: 
 Active suicidal ideation as indicated by a positive response (“Yes”) to Questions 4 or 5 or to 
the suicidal behavior questions of the “Since Last Visit” version of the eC-SSRS. 
 Moderately severe major depression as indicated by a PHQ-9 score of 15 to 19 if this 
represents an increase of 3 points compared to last visit. 
13. Subjects must be referred immediately to a mental healthcare professional and must be 
withdrawn in case of: 
 Active suicidal ideation as indicated by a positive response ("Yes") to Question 5 of the 
"Since Last Visit" version of the eC-SSRS  
 Any suicidal behavior since last visit. 
 Severe major depression as indicated by a PHQ-9 score ≥20. 
The mental health consultation will be documented must be recorded in source 
documentation. 
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 172 of 190 
Change #21 
Section 7.1 Description of investigational medicinal product(s) 
 Adalimumab is commercially available and will be supplied in a 1mL PFS at a concentration 
of 40mg/0.8mL or 40mg/0.4mL for sc injection. 
Has been changed to:  
 Adalimumab is commercially available and will be supplied as a PFS for sc injection (at a 
concentration of 40mg/0.8mL or 40mg/0.4mL depending on regional availability) in a 
single-use syringein a 1mL PFS at a concentration of 40mg/0.8mL or 40mg/0.4mL for sc 
injection. 
Change #22 
Section 7.2 Treatment(s) to be administered
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Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 173 of 190 
 
Table 7-1: 
Dosing scheme 
 
Initial Treatment 
Maintenance Treatment 
Week 
Dose Assignment 
0 
1,  
3 
4 
5,  
7 
8 
9, 
11 
12 
13, 
15 
16 
17, 
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
bimekizumab 320mg 
Q4W/Q4W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
bimekizumab 320mg 
Q4W/Q8W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
 
○ 
 
○○ 
○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
adalimumab 40mg 
▲▲ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
Q4W=every 4 weeks; Q8W=every 8 weeks 
Notes: A bimekizumab 160mg injection is depicted by a black circle (●). A placebo injection is depicted by a white circle (○). An adalimumab 40mg injection is 
depicted by a black triangle (▲) 
Has been changed to:  
Table 7-1: 
Dosing scheme 
Week 
Dose Assignment 
0 
1,  
3 
4 
5,  
7 
8 
9, 
11 
12 
13, 
15 
16 
17, 
19 
20 
21, 
23 
24 
28 
32 
36 
40 
44 
48 
52 
bimekizumab 320mg 
Q4W/Q4W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
bimekizumab 320mg 
Q4W/Q8W 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
○ 
●● 
 
○ 
 
○○ 
○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
●● 
○○ 
adalimumab 
40mg/bimekizumab 
320mg Q4W 
▲▲ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
○○ 
▲ 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
●● 
Q4W=every 4 weeks; Q8W=every 8 weeks 
Notes: A bimekizumab 160mg injection is depicted by a black circle (●). A placebo injection is depicted by a white circle (○). An adalimumab 40mg injection is 
depicted by a black triangle (▲).
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Change #23 
Section 7.6 Drug Accountability 
Blinded study staff may be delegated the responsibility to receive, inventory, and destroy the 
used kits. The packaging identifies each kit by a unique number that does not correlate to the 
contents and therefore, does not unblind study site staff. Unblinded study staff will be 
responsible for preparation (breaking tamper proof sticker on kit, etc) of the clinical study 
material, including recording the administration information on source documents. 
Has been changed to:  
Unblinded study staff will be delegated the responsibility to receive, inventory and destroy 
the used kits. The packaging identifies each kit by a unique number, but due to the 
commercial packaging of the comparator, the unblinded study staff will be responsible in 
order to maintain the blind. Blinded study staff may be delegated the responsibility to receive, 
inventory, and destroy the used kits. The packaging identifies each kit by a unique number that 
does not correlate to the contents and therefore, does not unblind study site staff. Unblinded 
study staff will be responsible for preparation (breaking tamper proof sticker on kit, etc) of the 
clinical study material, including recording the administration information on source documents. 
Change #24 
Section 7.8.2 Prohibited concomitant treatments (medications and therapies), Table 7-2 
Table 7-2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
Topicals except for those permitted (Section 7.8 1.1) 
2 weeks 
Systemic retinoids 
3 months  
Systemic treatment (nonbiological): 
systemic immunosuppressant agents (eg, 
methotrexate, cyclosporine, azathioprine, 
thioguanine) 
fumaric acid esters specifically used for the 
treatment of PSO 
systemic corticosteroids 
phototherapy or photochemotherapy 
1 month 
Anti-TNFs: 
adalimumab (including biosimilar) 
etanercept (including biosimilar) 
infliximab (including biosimilar), golimumab, 
certolizumab pegol 
 
Any exposure to adalimumab 
1 month for etanercept 
3 months for infliximab (including biosimilar), 
golimumab, certolizumab pegol 
Other biologics and other systemic therapies, eg: 
 
apremilast, tofacitinib 
2 weeks for apremilast and tofacitinib 
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Table 7-2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
alefacept, efalizumab, guselkumab 
3 months for alefacept, efalizumab, and 
guselkumab 
ustekinumab, briakinumab 
6 months for ustekinumab and briakinumab 
rituximab 
12 months for rituximab 
Anti-IL-17 therapy: 
brodalumab 
ixekizumab 
secukinumab 
3 months 
(bimekizumab is excluded per exclusion 
criteria) 
Any other antipsoriatic agent (systemic) under 
investigation (or approved after the protocol is 
approved) 
3 months or 5 half-lives, whichever is greater 
Any other antipsoriatic agent (topical) under 
investigation 
1 month 
IL-17=interleukin 17; PSO=psoriasis; TNF=tumor necrosis factor 
Has been changed to:  
Table 7-2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
Topicals except for those permitted (Section 7.8.1.1) 
2 weeks 
Systemic retinoids 
3 months  
Systemic treatment (nonbiological): 
systemic immunosuppressant agents (eg, 
methotrexate, cyclosporine, azathioprine, 
thioguanine) 
fumaric acid esters specifically used for the 
treatment of PSO 
systemic corticosteroids 
phototherapy or photochemotherapy 
1 month 
Anti-TNFs: 
adalimumab (including biosimilar) 
etanercept (including biosimilar) 
infliximab (including biosimilar), golimumab, 
certolizumab pegol 
 
Any exposure to adalimumab 
1 month for etanercept 
3 months for infliximab (including biosimilar), 
golimumab, certolizumab pegol 
Other biologics and other systemic therapies, eg: 
 
apremilast, tofacitinib 
2 weeks for apremilast and tofacitinib 
alefacept, efalizumab, guselkumab 
3 months for alefacept, efalizumab, and 
guselkumab 
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Table 7-2: 
Prohibited psoriasis medications 
Drug 
Washout period relative to Baseline Visit 
tildrakizumab, risankizumab 
5 months for tildrakizumab and 
risankizumab 
ustekinumab, briakinumab 
6 months for ustekinumab and briakinumab 
rituximab 
12 months for rituximab 
Anti-IL-17 therapy: 
brodalumab 
ixekizumab 
secukinumab 
3 months 
(bimekizumab is excluded per exclusion 
criteria) 
Any other antipsoriatic agent (systemic) under 
investigation (or approved after the protocol is 
approved) 
3 months or 5 half-lives, whichever is greater 
Any other antipsoriatic agent (topical) under 
investigation 
1 month 
IL-17=interleukin 17; PSO=psoriasis; TNF=tumor necrosis factor 
Change #25 
Section 7.10 Randomization and numbering of subjects, first paragraph 
An IRT will be used for assigning eligible subjects to a treatment regimen based on a 
predetermined production randomization and/or packaging schedule provided by UCB (or 
designee). The randomization schedule will be produced by the IRT vendor. The IRT will 
generate individual assignments for subject kits of IMP, as appropriate, according to the visit 
schedule. Subject treatment assignment will be stratified by region and prior biologic exposure 
(yes/no). The IRT will generate individual assignments for subject kits of IMP, as appropriate, 
according to the visit schedule. 
Has been changed to:  
An IRT will be used for assigning eligible subjects to a treatment regimen based on a 
predetermined production randomization and/or packaging schedule provided by UCB (or 
designee). The randomization schedule will be produced by the IRT vendor. The IRT will 
generate individual assignments for subject kits of IMP, as appropriate, according to the visit 
schedule. Subject treatment assignment will be stratified by region (North America, Western 
Europe, Central/Eastern Europe and Asia/Australia) and prior biologic exposure (yes/no). 
The IRT will generate individual assignments for subject kits of IMP, as appropriate, according 
to the visit schedule. 
Change #26 
Section 8 STUDY PROCEDURES BY VISIT, first bullet 
 Visit windows of ±3 days on either side of the scheduled dosing are permitted; however, the 
Investigator should try to keep the subjects on the original dosing schedule. The window of 
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±3 days is relative to Baseline and applicable for all subsequent visits. Changes to the dosing 
schedule outside of the 3-day window must be discussed with the Medical Monitor. 
 For the SFU Visit (20 weeks after the last dose), the visit should occur no more than 3 days 
prior to the scheduled visit date and within 7 days after the scheduled visit date 
(-3 days/+7 days). 
Has been changed to: 
 From the Week 1 Visit to the Week 24 visit, Visit visit windows of ±3 days on either side 
of the scheduled dosing are permitted; however, the Investigator should try to keep the 
subjects on the original dosing schedule. The window of ±3 days is relative to Baseline and 
applicable for all subsequent visits. From the Week 28 visit to the Week 52 visit, visit 
windows are ±7 days. Changes to the dosing schedule outside of the visit window must be 
discussed with the Medical Monitor. 
 The dosing window is ±3 days relative to the scheduled dosing visit through Week 24. 
The dosing window is ±7 days relative to the scheduled dosing visit from Week 28 
through the end of the study. 
 For the SFU Visit (20 weeks after the last final dose), the visit window is ±7 days relative 
to the scheduled visit date. should occur no more than 3 days prior to the scheduled 
visit date and within 7 days after the scheduled visit date ( 3 days/+7 days). 
Change #27 
Section 8.1 Screening Visit (2 to 4 weeks) 
Has been changed to:  
Section 8.1 Screening Visit (2 to 4 5 weeks) 
Change #28 
Section 8.1 Screening Visit (2 to 4 weeks) 
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB GOLD test be 
performed 
Has been changed to:  
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB GOLD test be 
performed 
Change #29 
Sections 8.2.1 Baseline Visit  
The following has been added to the bulleted list: 
 Physical examination including evaluation of signs and symptoms of active TB and risk for 
exposure to TB 
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Change #30 
Sections 8.2.8 Week 12 (±3 days)  
The following have been added to the bulleted list: 
 Body weight 
 Record 12-lead ECG 
Change #31 
Sections 8.2.8 Week 12 (±3 days) and 8.3.10 Week 48 (±3 days) 
The following has been added to the bulleted list: 
 TB questionnaire 
Change #32 
Sections 8.2.10 Week 16 (±3 days) 
The following have been deleted from the bulleted list: 
 Body weight  
 Record 12-lead ECG 
Change #33 
Sections 8.2.10 Week 16 (±3 days), 8.3.9 Week 44 (±3 days), and 8.3.11 Week 52 (±3 days) 
The following has been deleted from the bulleted list: 
 TB questionnaire 
Change #34 
Section 8.3.5 Week 28 (±3 days) 
The following has been added to the bulleted list: 
Obtain urine sample for the following analysis prior to dosing: 
 Hematology and biochemistry 
Change #35 
Sections 8.3.5 Week 28 (±3 days), 8.3.6 Week 32 (±3 days), 8.3.7 Week 36 (±3 days), 8.3.8 
Week 40 (±3 days), 8.3.9 Week 44 (±3 days), 8.3.10 Week 48 (±3 days), 8.3.11 Week 52 (±3 
days), and 8.3.12 Week 56 (±3 days) 
Has been changed to:  
Sections 8.3.5 Week 28 (±3 ±7 days), 8.3.6 Week 32 (±3 ±7 days), 8.3.7 Week 36 (±3 ±7 
days), 8.3.8 Week 40 (±3±7 days), 8.3.9 Week 44 (±3 ±7 days), 8.3.10 Week 48 (±3 ±7 days), 
8.3.11 Week 52 (±3 ±7 days), and 8.3.12 Week 56 (±3 ±7 days) 
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Change #36 
Sections 8.3.11 Week 52 (±3 days) 
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB GOLD test be 
performed 
Has been changed to:  
 IGRA tuberculosis test; it is recommended that the QuantiFERON TB GOLD test be 
performed 
 
Change #37 
Section 8.5 Safety Follow Up Visit (20 weeks after last dose ±-3/+7 days) 
Has been changed to: 
Section 8.5 Safety Follow Up Visit (20 weeks after last final dose ± 3/+7 days ±7 days) 
Change #38 
Section 9 ASSESSMENT OF EFFICACY 
The PASI, BSA, IGA, scalp IGA, mNAPSI, and pp-IGA should be performed by the 
Investigator, another delegated physician, or an appropriately qualified medical professional 
(based on local requirements) who has had documented training on how to perform these 
assessments correctly. Preferably, the same assessor should evaluate the subject at each 
assessment. 
Has been changed to: 
The PASI, BSA, IGA, scalp IGA, mNAPSI, and pp-IGA should be performed by the 
Investigator, another delegated physician, or an appropriately qualified medical professional 
(based on local requirements) who has had documented training on how to perform these 
assessments correctly. Preferably, the The same assessor should evaluate the subject at each 
assessment. 
Change #39 
Section 9.10 Patient Global Assessment of psoriasis, second and third paragraphs 
The Patient Global Assessment of PSO will be performed as part of the patient symptoms diary 
from baseline through the Initial Treatment Period; the assessment is to completed within a +3 
day completion window at each of the visits specified in Table 5-1. 
During the double-blind Maintenance Treatment Period, this assessment will be completed 
within a +3 day completion window at the visits specified in Table 5-1. 
Has been changed to:  
The Patient Global Assessment of PSO will be performed as part of the patient symptoms diary 
from baseline Screening through the Initial Treatment Period; the assessment is to be 
completed within a +3 day completion window at each of the visits specified in Table 5 1. 
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During the double-blind Maintenance Treatment Period, this assessment will be completed 
within a +3 day completion window at the visits specified in Table 5-1. 
Change #40 
Section 9.11 Patient Symptom Diary responses, second paragraph 
The ePRO diary will also administer the patient global assessment of PSO as noted above 
appropriate anchor items at the end of every study week. The ePRO diary software will be 
programmed such that the subjects will be given a window of opportunity to complete the ePRO 
diaryeach evening. The data collected on the ePRO diary will be uploaded to a central server 
database and will be 21 CFR Part 11 compliant. Appropriate GCP procedures (including 
subject/site training and testing) will be performed at the study sites. 
Has been changed to:  
The ePRO diary will also administer the patient global assessment of PSO as noted above 
appropriate anchor items at the end of every study week. The ePRO diary software will be 
programmed such that the subjects will be given a window of opportunity to complete the ePRO 
diary each evening. The data collected on the ePRO diary will be uploaded to a central server 
database and will be 21 CFR Part 11 compliant. Appropriate GCP procedures (including 
subject/site training and testing) will be performed at the study sites. 
Change #41 
Section 9.12 PASE questionnaire 
Standardized responses are based on 5 categories relating to agreement (strongly agree [1], agree 
[2], no idea [3], disagree [4], and strongly disagree [5]). The total maximum score is 75 points 
(symptom score: 35 points and function score: 40 points).  
Has been changed to:  
Standardized responses are based on 5 categories relating to agreement (strongly agree [1 5], 
agree [2 4], no idea [3], disagree [4 2], and strongly disagree [5 1]). The total maximum score 
is 75 points (symptom score: 35 points and function score: 40 points).  
Change #42 
Section 12.1.4 Pregnancy 
A pregnancy becomes an SAE in the following circumstances: miscarriage, abortion (elective or 
spontaneous), unintended pregnancy after hormonal contraceptive failure (if the hormonal 
contraceptive was correctly used), ectopic pregnancy, fetal demise, or any congenital 
anomaly/birth defect of the baby.  
Has been changed to:  
A pregnancy becomes an SAE in the following circumstances: miscarriage, abortion (elective 
or spontaneousel elective abortion when medically indicated (e.g. when pregnancy is 
endangering life or health of woman or when fetus will be born with severe abnormalities), 
unintended pregnancy after hormonal contraceptive failure (if the hormonal contraceptive was 
correctly used), ectopic pregnancy, fetal demise, or any congenital anomaly/birth defect of the 
baby.  
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Change #43 
Section 12.2 Laboratory measurements 
Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
Basophils 
Calcium 
pH 
Eosinophils 
Chloride 
Albumin (protein) 
Lymphocytes 
Magnesium 
Glucose 
Atypical lymphocytes 
Potassium 
Blood 
Monocytes 
Sodium 
Leukocyte esterase 
Neutrophils 
Glucose 
Nitrite 
Hematocrit 
BUN 
Urine dipstick for pregnancy testingb 
Hemoglobin 
Creatinine 
Urine drug screend 
MCH 
ALP 
 
MCHC 
AST 
 
MCV 
ALT 
 
Platelet count 
GGT 
 
RBC count 
Total bilirubin 
 
WBC count 
LDH 
 
 
Serum pregnancy testingb 
 
Has been changed to:  
Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
Basophils 
Calcium 
pH 
Eosinophils 
Chloride 
Albumin (protein) 
Lymphocytes 
Magnesium 
Glucose 
Atypical lymphocytes 
Potassium 
Blood 
Monocytes 
Sodium 
Leukocyte esterase 
Neutrophils 
Glucose 
Nitrite 
Hematocrit 
BUN 
Urine dipstick for pregnancy testingb 
Hemoglobin 
Creatinine 
Urine drug screend 
MCH 
ALP 
 
MCHC 
AST 
 
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Table 12-2: Laboratory measurements 
Hematology 
Chemistry 
Urinalysis dipsticka 
MCV 
ALT 
 
Platelet count 
GGT 
 
RBC count 
Total bilirubin 
 
WBC count 
LDH 
 
 
Serum pregnancy testingb 
 
 
Change #44 
Section 12.2.1 Evaluation of PDILI 
Rechallenge with a substance potentially causing drug-induced liver injury is dangerous, may be 
fatal, and must not occur. 
Has been changed to:  
Rechallenge with a substance potentially causing drug induced liver injury is dangerous, 
may be fatal, and must not occur. 
Change #45 
Section 12.2.1.2.1 IMP restart/rechallenge (if applicable) 
Rechallenge with a substance potentially causing drug-induced liver injury is dangerous, may be 
fatal, and must not occur. 
Has been changed to:  
Section 12.2.1.2.1 IMP restart/rechallenge (if applicable) 
Rechallenge with a substance potentially causing drug induced liver injury is dangerous, 
may be fatal, and must not occur. Rechallenge with IMP can occur only if ALL of the 
following requirements are met: 
 The results of additional testing and monitoring described in Section 12.2.1.3 and 
Section 12.2.1.4 confirm a nondrug-related cause for the abnormal hepatic laboratory 
parameters and any associated symptoms (ie, a subsequent alternative diagnosis fully 
explains the hepatic findings).  
 The subject has shown clear therapeutic benefit from the IMP. 
 Subject’s ALT or AST elevations do not exceed ≥5xULN. 
 Subject’s total bilirubin is <2xULN. 
 Subject has no signs or symptoms of hypersensitivity or hepatitis.  
 The rechallenge is approved by the UCB responsible physician, DMC, and a 
hepatologist. The hepatologist must be external to UCB but may be a member of the 
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DMC. It is recommended that the hepatologist be a local hepatology expert or the 
hepatologist treating the subject. 
 Subject agrees to the Investigator-recommended monitoring plan. 
Change #46 
Section 12.3.1 Assessment and management of TB and TB risk factors 
At Screening, all subjects will have an IGRA test (QuantiFERON TB GOLD is recommended), a 
chest x-ray (unless already performed within 3 months of Screening) and examination for signs 
and symptoms of TB. 
Change #47 
Section 12.3.1 Assessment and management of TB and TB risk factors 
b. High risk of acquiring TB infection: 
 Known exposure to another person with active TB infection within the 3 months prior to 
Screening. 
Has been changed to: 
b. High risk of acquiring TB infection: 
 Known close exposure to another person with active TB infection within the 3 months 
prior to Screening. 
Has been changed to:  
At Screening, all subjects will have an IGRA test (QuantiFERON TB GOLD test is 
recommended), a chest x-ray (unless already performed within 3 months of Screening) and 
examination for signs and symptoms of TB. 
Change #48 
Section 12.3.1.1 Tuberculosis assessment by IGRA 
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB GOLD is 
recommended) will be performed as described in Table 5-1 for all subjects. 
Has been changed to:  
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB GOLD test is 
recommended) will be performed as described in Table 5-1 for all subjects. 
Change #49 
Section 12.3.1.3 Tuberculosis questionnaire, last paragraph 
Subjects with a latent or active TB infection must be withdrawn from the study. 
Has been deleted: 
Subjects with a latent or active TB infection must be withdrawn from the study. 
Change #50 
Section 12.3.1.4 Tuberculosis management, second paragraph 
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During the study, subjects who develop evidence of LTB infection or active TB must 
immediately stop further administration of IMP and will be referred to an appropriate TB 
specialist (pulmonologist or infectious disease specialist) for further evaluation. Evidence of 
LTB infection is defined as subject’s IGRA test converts to positive or indeterminate (and 
confirmed indeterminate on repeat), or the subject’s questionnaire or history and physical 
indicates that TB infection or exposure may have occurred. Evidence of active TB includes, in 
addition to the aforementioned tests, signs and symptoms of organ involvement. In either 
situation, the subject should be carefully assessed by a TB specialist for active TB. Subjects 
diagnosed with active TB or LTB infection should be withdrawn from the study and receive 
appropriate TB or prophylaxis therapy. 
Has been changed to: 
During the study, subjects who develop evidence of LTB infection or active TB must 
immediately stop further administration of IMP and will be referred to an appropriate TB 
specialist (pulmonologist or infectious disease specialist) for further evaluation. Evidence of 
LTB infection is defined as subject’s IGRA test converts to positive or indeterminate (and 
confirmed indeterminate on repeat), or the subject’s questionnaire or history and physical 
indicates that TB infection or exposure may have occurred. Evidence of active TB includes, in 
addition to the aforementioned tests, signs and symptoms of organ involvement. In either 
situation, the subject should be carefully assessed by a TB specialist for active TB. Subjects 
diagnosed with active TB or LTB infection should be withdrawn from the study and receive 
appropriate TB or prophylaxis therapy. 
Change #51 
Section 12.3.2 Pregnancy testing 
A negative urine pregnancy test result should be obtained immediately prior to each 
administration of IMP and at all subsequent postdosing visits. 
Has been changed to:  
A negative urine pregnancy test result should be obtained immediately prior to each 
administration of IMP and at all subsequent postdosing visitsat the visits specified in 
Table 5-1. 
Change #52 
Section 14.1 Definition of analysis sets 
The following analysis set has been added: 
The Bimekizumab Set (BKZ Set) will consist of all subjects who have received at least 1 
dose of bimekizumab in this study. 
Change #53 
Section 14.1 Definition of analysis sets 
The Full Analysis Set (FAS) will consist of all randomized subjects that receive at least 1 dose of 
the IMP and have a valid measurement of the primary efficacy variable at Baseline. 
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Has been changed to: 
The Full Analysis Set (FAS) will consist of all randomized subjects that receive at least 1 dose of 
the IMP and have a valid measurement for each of the co-primary efficacy variable variables at 
Baseline. 
Change #54 
Section 14.2 General statistical considerations, third paragraph 
The hypotheses (H1, H2, H3, H4, H5, H6, H7, H8, and H9) comparing bimekizumab vs. 
adalimumab will be tested at a 2-sided alpha level of 0.05. 
Has been changed to: 
The hypotheses (H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11 and H12) comparing bimekizumab 
vs. adalimumab will be tested at a 2-sided alpha level of 0.05. 
Change #55 
Section 14.2 General statistical considerations 
Figure 14-1: Sequence of testing 
 
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Has been changed to:  
Figure 14-1: Sequence of testing 
 
 
Change #56 
Section 14.3.2.1.2 Maintenance Treatment Period 
The secondary efficacy variables in the Maintenance Treatment Period include PASI90, 
PASI100, and IGA at Week 24 and Week 56.  
Has been changed to:  
The secondary efficacy variables in the Maintenance Treatment Period include PASI90, 
PASI100, and IGA at Week 24 and Week 56.  
In order to differentiate between subjects remaining on Q4W dosing from those switching 
to Q8W dosing at Week 16, the treatment comparisons at Week 24 for PASI100, PASI90 
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and IGA will be performed in 2 different ways using the following randomized treatment 
arms: 
1. Bimekizumab Q4W and bimekizumab  Q4W/Q8W combined vs adalimumab (testing 
H7, H8, and H9) 
2. Bimekizumab Q4W only vs adalimumab (testing H10, H11, and H12) 
Change #57 
Section 14.4 Subgroup analyses 
Subgroup analyses will be performed on the primary and secondary efficacy variables that are 
part of the fixed sequence testing procedure described in Section 14.3. The following variables 
for subgroup analyses will be defined: age, gender, disease duration, region, weight, body mass 
index (BMI), prior systemic chemotherapy or photochemotherapy, prior biologic exposure, prior 
systemic therapy of any kind, Baseline disease severity, and antibody positivity. These 
summaries will be based on imputed data (NRI) and will include descriptive statistics only. 
Has been changed to:  
Subgroup analyses will be performed on the primary and secondary efficacy variables that are 
part of the fixed sequence testing procedure described in Section 14.3. The following variables 
for subgroup analyses will be defined: age, gender, disease duration, region, weight, body mass 
index (BMI), prior systemic chemotherapy or photochemotherapy phototherapy, prior 
biologic exposure, prior systemic therapy of any kind, Baseline disease severity, and antibody 
positivity. These summaries will be based on imputed data (NRI) and will include descriptive 
statistics only. 
Change #58 
Section 14.5.2 Pharmacokinetic analyses 
The following text has been deleted: 
The relationship between efficacy response (PASI/IGA) and bimekizumab plasma 
concentration will be explored via graphical and a model based approach to quantify the 
time course of dose/exposure response. In addition, the relationship between safety and 
exposure will also be explored. The data will be combined with that from other 
bimekizumab trials in PSO for a pooled, cross trial analysis. The details of this analysis will 
be described in a data analysis plan, and the analysis itself will be reported separately from 
the Clinical Study Report (CSR). The details of the model and the approach will be 
specified in a data analysis plan. 
Change #59 
Section 14.6 Handling of protocol deviations 
Important protocol deviations are deviations from the protocol which potentially could have a 
meaningful impact on study conduct, or on the primary efficacy, key safety, or PK/PD outcomes 
for an individual subject. 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 188 of 190 
Has been changed to:  
Important protocol deviations are deviations from the protocol which potentially could have a 
meaningful impact on study conduct, or on the primary efficacy, key safety, or PK/PD outcomes 
for an individual subject. 
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UCB 
 
06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 189 of 190 
19 
DECLARATION AND SIGNATURE OF INVESTIGATOR 
I confirm that I have carefully read and understood this protocol and agree to conduct this 
clinical study as outlined in this protocol, according to current Good Clinical Practice and local 
laws and requirements. 
I will ensure that all subInvestigators and other staff members read and understand all aspects of 
this protocol. 
I have received and read all study-related information provided to me. 
The objectives and content of this protocol as well as the results deriving from it will be treated 
confidentially, and will not be made available to third parties without prior authorization by 
UCB. 
All rights of publication of the results reside with UCB, unless other agreements were made in a 
separate contract. 
Investigator: 
 
 
 
 
Printed name  
 
Date/Signature 
 
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06 Apr 2018 
Clinical Study Protocol 
Bimekizumab 
PS0008 
 
 
 
Confidential 
Page 190 of 190 
20 
SPONSOR DECLARATION 
I confirm that I have carefully read and understand this protocol and agree to conduct this 
clinical study as outlined in this protocol and according to current Good Clinical Practice. 
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Approval Signatures
Name:
ps0008-protocol-amend-2
Version:
1. 0
Document Number:
CLIN-000116785
Title:
PS0008 Protocol Amendment 2
Approved Date:
11 Apr 2018
Document Approvals
Approval
Verdict: Approved
Name: Christopher Cioffi
Capacity: Clinical
Date of Signature: 11-Apr-2018 12:41:40 GMT+0000
Approval
Verdict: Approved
Name: Nancy Cross
Capacity: Clinical
Date of Signature: 11-Apr-2018 12:57:27 GMT+0000
Approval
Verdict: Approved
Name: Jackie Thirlwell
Capacity: Clinical
Date of Signature: 11-Apr-2018 13:43:25 GMT+0000
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