A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study to Evaluate the Efficacy and Safety of Bimekizumab in Adult Korean Study Participants With Moderate to Severe Plaque Psoriasis
Phase: PHASE3
Conditions: Moderate to Severe Plaque Psoriasis
Sponsor: UCB Biopharma SRL

UCB 
 
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Bimekizumab 
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A PHASE 3, MULTICENTER, RANDOMIZED, DOUBLE-BLIND, 
PLACEBO-CONTROLLED, PARALLEL GROUP STUDY TO 
EVALUATE THE EFFICACY AND SAFETY OF BIMEKIZUMAB 
IN ADULT KOREAN STUDY PARTICIPANTS WITH MODERATE 
TO SEVERE PLAQUE PSORIASIS 
PROTOCOL PS0032 AMENDMENT 3 
PHASE 3 
 
SHORT TITLE: 
A randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of 
bimekizumab in adult Korean study participants with moderate to severe plaque psoriasis 
Sponsor: 
UCB Biopharma SRL 
Allée de la Recherche 60 
1070 Brussels 
BELGIUM 
 
Regulatory agency identifying number: 
IND Number: 
128707 
 
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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PROTOCOL AMENDMENT SUMMARY OF CHANGES TABLE 
Document History 
Document 
Date 
Type of amendment 
Original Protocol 
17 Dec 2020 
Not applicable 
PS0032 Protocol Amendment 1 
24 Mar 2021 
Substantial 
PS0032 Protocol Amendment 2 
12 May 2021 
Substantial 
PS0032 Protocol Amendment 3 
16 Aug 2021 
Substantial 
 
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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 
Email 
Global: DS_ICT@ucb.com  
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PROTOCOL AMENDMENT SUMMARY OF CHANGES 
Amendment 3 (16 Aug 2021) 
Overall rationale for the amendment 
The purpose of this substantial amendment is to correct minor inconsistencies to be consistent 
within the protocol and across other psoriasis (PSO) studies in the development program. 
 
Section # and 
Name 
Description of Change 
Brief Rationale 
5.2 Exclusion 
criteria 
Revised exclusion criterion 6. 
Minor clarification for 
consistency with other PSO 
studies. 
Section 4.4 End of 
study definition 
Corrected the criteria for completion of the 
study. 
Minor clarification for 
consistency with other PSO 
studies. 
5.4 Screen failures 
Revised the text to state that study 
participants with latent tuberculosis diagnosed 
at Screening who then complete a full course 
of prophylaxis treatment can be rescreened 
after completion of 4 weeks of prophylaxis.   
Minor correction for 
consistency with Exclusion 
criterion #4.  
8.2.7.2 Assessments 
at Screening 
Revised the text to state that study 
participants with latent tuberculosis diagnosed 
at Screening who then complete a full course 
of prophylaxis treatment can be rescreened 
after completion of 4 weeks of prophylaxis.   
Minor correction for 
consistency with Exclusion 
criterion #4. 
8.2.7.2 Assessments 
at Screening 
Corrected the footnote under Figure 8-1 to 
state that study participants with latent 
tuberculosis diagnosed at Screening who then 
complete a full course of prophylaxis 
treatment can be rescreened after completion 
of 4 weeks of prophylaxis.   
Minor correction for 
consistency with Exclusion 
criterion #4. 
8.2.7.3.5 Latent TB 
 Revised the text to state that study 
participants with latent tuberculosis diagnosed 
at Screening who then complete a full course 
of prophylaxis treatment can be rescreened 
after completion of 4 weeks of prophylaxis.   
Minor correction for 
consistency with Exclusion 
criterion #4.  
 
 
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TABLE OF CONTENTS 
PROTOCOL AMENDMENT SUMMARY OF CHANGES .................................................... 4 
Amendment 3 (16 Aug 2021) .................................................................................................... 4 
Overall rationale for the amendment ..................................................................................... 4 
1 
PROTOCOL SUMMARY ............................................................................................... 10 
1.1 
Synopsis ....................................................................................................................... 10 
1.2 
Schema ......................................................................................................................... 15 
1.3 
Schedule of activities ................................................................................................... 16 
2 
INTRODUCTION ........................................................................................................... 19 
2.1 
Study rationale ............................................................................................................. 19 
2.2 
Background .................................................................................................................. 19 
2.3 
Benefit/risk assessment ................................................................................................ 20 
3 
OBJECTIVES AND ENDPOINTS ................................................................................. 21 
4 
STUDY DESIGN ............................................................................................................. 23 
4.1 
Overall design .............................................................................................................. 23 
4.2 
Scientific rationale for study design ............................................................................ 24 
4.3 
Justification for dose .................................................................................................... 24 
4.4 
End of study definition................................................................................................. 24 
5 
STUDY POPULATION .................................................................................................. 25 
5.1 
Inclusion criteria .......................................................................................................... 25 
5.2 
Exclusion criteria ......................................................................................................... 26 
5.3 
Lifestyle restrictions..................................................................................................... 29 
5.4 
Screen failures .............................................................................................................. 29 
6 
STUDY TREATMENTS ................................................................................................. 30 
6.1 
Treatments administered .............................................................................................. 30 
6.2 
Preparation, handling, storage, and accountability requirements ................................ 30 
6.2.1 
Drug accountability ............................................................................................. 31 
6.3 
Measures to minimize bias: randomization and blinding ............................................ 32 
6.3.1 
Procedures for maintaining and breaking the treatment blind ............................. 32 
6.3.1.1 
Maintenance of study treatment blind ....................................................... 32 
6.3.1.2 
Breaking the treatment blind in an emergency situation ........................... 32 
6.4 
Treatment compliance .................................................................................................. 33 
6.5 
Concomitant medications/treatments ........................................................................... 33 
6.5.1 
Permitted concomitant treatments (medications and therapies) .......................... 33 
6.5.2 
Prohibited concomitant treatments (medications and therapies) ......................... 34 
6.5.3 
Vaccines ............................................................................................................... 35 
6.5.4 
Rescue medication ............................................................................................... 35 
6.6 
Dose modification ........................................................................................................ 35 
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6.7 
Criteria for study hold or dosing stoppage ................................................................... 35 
6.8 
Treatment after the end of the study ............................................................................ 35 
7 
DISCONTINUATION OF IMP AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL ........................................................................ 35 
7.1 
Discontinuation of IMP................................................................................................ 35 
7.1.1 
Potential drug-induced liver injury IMP discontinuation criteria ........................ 37 
7.1.1.1 
Follow-up evaluation ................................................................................. 38 
7.1.2 
Clinical laboratory criteria ................................................................................... 38 
7.1.3 
Treatment interruptions/temporary discontinuation of IMP ................................ 38 
7.2 
Participant discontinuation/withdrawal from the study ............................................... 39 
7.3 
Lost to follow up .......................................................................................................... 39 
8 
STUDY ASSESSMENTS AND PROCEDURES ........................................................... 40 
8.1 
Efficacy assessments .................................................................................................... 40 
8.1.1 
PASI ..................................................................................................................... 40 
8.1.2 
IGA 41 
8.1.3 
DLQI .................................................................................................................... 42 
8.1.4 
Scalp IGA ............................................................................................................ 42 
8.1.5 
PSD (P-SIM) responses ....................................................................................... 43 
8.2 
Safety assessments ....................................................................................................... 43 
8.2.1 
Physical examination ........................................................................................... 43 
8.2.2 
Vital signs ............................................................................................................ 44 
8.2.3 
12-lead ECGs ....................................................................................................... 44 
8.2.4 
PHQ-9 .................................................................................................................. 44 
8.2.5 
Clinical safety laboratory assessments ................................................................ 44 
8.2.6 
Neuropsychiatric AE monitoring/suicidal risk monitoring ................................. 44 
8.2.7 
Assessment and management of TB and TB risk factors .................................... 45 
8.2.7.1 
Definitions ................................................................................................. 45 
8.2.7.2 
Assessments at Screening .......................................................................... 46 
8.2.7.3 
Assessment and reporting of TB and TB risk factors during the study..... 48 
8.2.8 
Adverse events and SAEs .................................................................................... 50 
8.2.8.1 
Time period and frequency for collecting AE and SAE information ........ 50 
8.2.8.2 
Method of detecting AEs and SAEs .......................................................... 50 
8.2.8.3 
Follow-up of AEs and SAEs ..................................................................... 51 
8.2.8.4 
Regulatory reporting requirements for SAEs ............................................ 51 
8.2.8.5 
Pregnancy .................................................................................................. 51 
8.2.8.6 
AEs of special interest ............................................................................... 51 
8.2.8.7 
Other safety topics of interest .................................................................... 52 
8.2.8.8 
Anticipated SAEs ...................................................................................... 52 
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8.3 
Safety signal detection ................................................................................................. 53 
8.4 
Treatment of overdose ................................................................................................. 53 
8.5 
Pharmacokinetics ......................................................................................................... 53 
8.6 
Genetics........................................................................................................................ 54 
8.7 
Pharmacodynamics ...................................................................................................... 54 
8.8 
Biomarkers ................................................................................................................... 54 
8.9 
Immunogenicity assessments ....................................................................................... 54 
8.10 
Health economics or medical resource utilization and health economics ................... 54 
9 
STATISTICAL CONSIDERATIONS ............................................................................. 54 
9.1 
Definition of analysis sets ............................................................................................ 54 
9.2 
General statistical considerations ................................................................................. 55 
9.3 
Planned efficacy/outcome analyses ............................................................................. 55 
9.3.1 
Efficacy estimands ............................................................................................... 55 
9.3.2 
Analysis of the primary efficacy/primary endpoint ............................................. 56 
9.3.3 
Secondary efficacy endpoint analyses ................................................................. 57 
9.3.4 
Tertiary efficacy endpoint analyses ..................................................................... 58 
9.4 
Planned safety and other analyses................................................................................ 58 
9.4.1 
Safety analyses ..................................................................................................... 58 
9.4.1.1 
AEs 58 
9.4.1.2 
Vital signs .................................................................................................. 59 
9.4.1.3 
Hematology/biochemistry ......................................................................... 59 
9.4.1.4 
Physical examination ................................................................................. 59 
9.4.1.5 
ECG ........................................................................................................... 59 
9.4.1.6 
PHQ-9 ........................................................................................................ 59 
9.4.1.7 
C-SSRS ...................................................................................................... 59 
9.4.2 
Pharmacokinetics and antidrug antibody analyses .............................................. 59 
9.5 
Handling of protocol deviations................................................................................... 60 
9.6 
Handling of dropouts or missing data .......................................................................... 60 
9.7 
Planned interim analysis and data monitoring ............................................................. 61 
9.8 
Determination of sample size ....................................................................................... 61 
10 SUPPORTING DOCUMENTATION AND OPERATIONAL CONSIDERATIONS... 61 
10.1 
Appendix 1: Regulatory, ethical, and study oversight considerations ......................... 61 
10.1.1 
Regulatory and ethical considerations ................................................................. 61 
10.1.2 
Financial disclosure ............................................................................................. 62 
10.1.3 
Informed consent process .................................................................................... 62 
10.1.4 
Data protection ..................................................................................................... 63 
10.1.5 
Committee structure ............................................................................................. 63 
10.1.6 
Data quality assurance ......................................................................................... 63 
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10.1.6.1 
eCRF completion ....................................................................................... 64 
10.1.6.2 
Apps ........................................................................................................... 64 
10.1.7 
Source documents ................................................................................................ 65 
10.1.8 
Study and site closure .......................................................................................... 65 
10.1.9 
Publication policy ................................................................................................ 65 
10.1.10 
Clinical trial registration and results disclosure ................................................... 66 
10.2 
Appendix 2: Clinical laboratory tests .......................................................................... 67 
10.3 
Appendix 3: AEs – definitions and procedures for recording, evaluating, follow up, 
and reporting ................................................................................................................ 70 
10.4 
Appendix 4: Contraceptive guidance and collection of pregnancy information ......... 75 
10.5 
Appendix 5: Genetics ................................................................................................... 78 
10.6 
Appendix 6: Liver safety – suggested actions and follow-up assessments ................. 79 
10.6.1 
Consultation with Medical Monitor and local hepatologist................................. 83 
10.6.2 
Immediate action: determination of IMP discontinuation ................................... 83 
10.6.2.1 
IMP restart/rechallenge ............................................................................. 83 
10.6.3 
Testing: identification/exclusion of alternative etiology ..................................... 84 
10.7 
Appendix 7: Medical device AEs, adverse device effects, SAEs, and device 
deficiencies: definition and procedures for recording, evaluating, follow up, and 
reporting ....................................................................................................................... 86 
10.8 
Appendix 8: Rapid alert procedures ............................................................................ 87 
10.9 
Appendix 9: Country-specific requirements ................................................................ 88 
10.10 Appendix 10: Abbreviations and trademarks .............................................................. 89 
10.11 Appendix 11: Protocol amendment history ................................................................. 92 
Amendment 1 (24 Mar 2021) .................................................................................................. 92 
Overall rationale for the amendment ................................................................................... 92 
Amendment 2 (12 May 2021) .................................................................................................. 93 
Overall rationale for the amendment ................................................................................... 93 
11 REFERENCES ................................................................................................................ 94 
SPONSOR DECLARATION .................................................................................................. 96 
 
LIST OF TABLES 
Table 1-1: 
Schedule of study assessments......................................................................... 16 
Table 6-1: 
Treatments administered .................................................................................. 30 
Table 8‒1: 
Body areas for calculation of percent BSA for PASI ...................................... 41 
Table 8-2: 
Five-point IGA ................................................................................................. 42 
Table 8-3: 
Scalp IGA......................................................................................................... 42 
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Table 8-4: 
Anticipated SAEs for study participants with moderate to severe plaque 
PSO .................................................................................................................. 52 
Table 10-1: 
Protocol-required safety laboratory assessments ............................................. 68 
Table 10-2: 
Required investigations and follow up for PDILI............................................ 80 
Table 10-3: 
PDILI laboratory measurements ...................................................................... 84 
Table 10-4: 
PDILI information to be collected ................................................................... 85 
 
LIST OF FIGURES 
Figure 1-1: 
Study schematic ............................................................................................... 15 
Figure 8-1: 
Decision tree for IGRA TB results at Screening ............................................. 47 
 
 
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1 
PROTOCOL SUMMARY 
1.1 
Synopsis 
Protocol title: A phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel 
group study to evaluate the efficacy and safety of bimekizumab in adult Korean study 
participants with moderate to severe plaque psoriasis 
Short title: A randomized, double-blind, placebo-controlled study to evaluate the efficacy and 
safety of bimekizumab in adult Korean study participants with moderate to severe plaque 
psoriasis 
Rationale: The purpose of this study is to evaluate the efficacy and safety of bimekizumab in 
adult Korean study participants (aged at least 19 years) with moderate to severe plaque psoriasis 
(PSO). Following the completion of the pivotal global Phase 3 program of bimekizumab in 
moderate to severe PSO, the aim of this study is to bridge the existing evidence of efficacy and 
safety of bimekizumab from the Phase 3 program with limited Korean participation to a Korean 
population of study participants with moderate to severe PSO. 
Objectives and endpoints 
Objectives 
Endpoints 
Primary 
Co-Primary Endpoints 
To evaluate the efficacy of 
bimekizumab compared with placebo 
Co-Primary Endpoint 1: 
• 
Participant-level outcome: Psoriasis Area and Severity 
Index (PASI)90 response at Week 16 
Co-Primary Endpoint 2: 
• 
Participant-level outcome: Investigator’s Global 
Assessment (IGA) 0/1 (clear or almost clear with at least a 
2-category improvement from Baseline) response at 
Week 16 
Secondary 
To evaluate the efficacy of 
bimekizumab compared with placebo 
at achieving complete skin clearance 
(PASI100/IGA 0) 
• 
Participant-level outcome: PASI100 response at Week 16 
• 
Participant-level outcome: IGA 0 (clear with at least a 
2-category improvement from Baseline) response at 
Week 16 
To evaluate the efficacy of 
bimekizumab compared with placebo 
at achieving rapid response (PASI75) 
• 
Participant-level outcome: PASI75 response at Week 4 
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Objectives 
Endpoints 
To evaluate the efficacy of 
bimekizumab compared with placebo 
on itch, pain, and scaling 
Reported by study participants using the patient symptom 
diary (PSD) (also published as Patient Symptom and Impact 
Measure [P-SIM] [Gottlieb et al, 2020]): 
• 
Participant-level outcome: PSD (P-SIM) response for itch 
at Week 16 
• 
Participant-level outcome: PSD (P-SIM) response for pain 
at Week 16 
• 
Participant-level outcome: PSD (P-SIM) response for 
scaling at Week 16 
To evaluate the efficacy of 
bimekizumab compared with placebo 
on the change in psoriatic scalp 
disease in study participants with 
scalp psoriasis (PSO) at Baseline 
• 
Participant-level outcome: Scalp IGA 0/1 (clear or almost 
clear with at least a 2-category improvement from 
Baseline) response at Week 16 for study participants with 
scalp PSO at Baseline 
To assess the effect of bimekizumab 
compared with placebo on quality of 
life (QOL) 
• 
Participant-level outcome: Dermatology Life Quality 
Index (DLQI) 0/1 response at Week 16 
To evaluate the effect of 
bimekizumab compared with placebo 
on percent change from Baseline in 
body surface area (BSA) affected by 
PSO 
• 
Participant-level outcome: Percent change from Baseline 
in BSA affected by PSO at Week 16 
To evaluate the safety of 
bimekizumab 
• 
Incidence of treatment-emergent adverse events (TEAEs) 
throughout the study 
• 
Incidence of treatment-emergent serious adverse 
events (TE-SAEs) throughout the study 
• 
Incidence of TEAEs leading to permanent discontinuation 
of investigational medicinal product (IMP) throughout the 
study 
To assess the effect of bimekizumab 
on depression occurrence or 
worsening 
• 
Change from Baseline in Patient Health Questionnaire 
(PHQ)-9 at Week 16 
Tertiary 
To evaluate the pharmacokinetics 
(PK) of bimekizumab in study 
participants with moderate to severe 
PSO 
• 
Plasma bimekizumab concentrations over the study 
duration 
To evaluate the immunogenicity of 
bimekizumab 
• 
Anti-bimekizumab antibody status over the study duration 
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Objectives 
Endpoints 
To assess the efficacy of 
bimekizumab compared with placebo 
over time 
• 
PASI75 response over time 
• 
PASI90 response over time 
• 
PASI100 response over time 
• 
Absolute and percent change from Baseline in PASI score 
over time 
• 
Percentage of study participants with absolute PASI score 
≤1, ≤2, ≤3, and ≤5 over time 
• 
Time to PASI50, PASI75, PASI90, and PASI100 
response 
• 
IGA 0/1 response (with at least 2-category improvement 
from Baseline) over time 
• 
IGA 0 response (with at least 2-category improvement 
from Baseline) over time 
• 
Scalp-specific IGA (scalp IGA) 0/1 response (clear or 
almost clear with at least 2-category improvement from 
Baseline for participants with scalp PSO at Baseline) over 
time 
• 
Percentage of study participants with absolute BSA 
affected by PSO=0%, ≤1%, ≤3% and ≤5% over time 
• 
Percentage of study participants achieving a DLQI Total 
Score of 0 or 1 over time 
• 
Change from Baseline in DLQI Total Score over time 
• 
PSD (P-SIM) response rates over time 
• 
Change from Baseline in PSD (P-SIM) scores over time 
To further evaluate the safety of 
bimekizumab compared with placebo 
over time 
• 
Selected safety topics of interest TEAEs 
• 
Change from Baseline in laboratory variables 
(hematology and biochemistry) 
• 
Incidence of markedly abnormal laboratory values 
• 
Change from Baseline in vital signs 
• 
Incidence of markedly abnormal vital signs 
• 
Change from Baseline in electrocardiogram (ECG) 
parameters 
• 
ECG outliers 
• 
Change from Baseline in PHQ-9 
• 
Incidence of PHQ-9 scores ≥15 and ≥20 
• 
Incidence of suicidal ideation, suicidal behavior, or self-
injurious behavior without suicidal intent (from Columbia 
Suicide Severity Rating Scale [C-SSRS]) 
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Overall design 
PS0032 is a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel group 
study to evaluate the efficacy and safety of bimekizumab compared with placebo in adult Korean 
study participants with moderate to severe plaque PSO. 
The study population consists of adult Korean study participants (≥19 years of age) with a 
diagnosis of moderate to severe plaque PSO (Baseline PASI ≥12 and BSA affected by PSO 
≥10% and IGA score ≥3 on a 5-point scale) who are a candidate for systemic PSO therapy and/or 
phototherapy. 
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 the Screening Period, eligible study participants will be informed about the 
study and sign the Informed Consent Form (ICF). Following signed informed consent, all 
screening procedures and laboratory tests (hematology, urine, and biochemistry) will be 
performed per the Schedule of Activities (SoA) (Table 1-1). The Screening Period will also 
enable washout of any medications not permitted for use during the study. Study participants 
who require prophylaxis for latent tuberculosis (LTB) infection must be on treatment for at least 
4 weeks prior to the first dose of IMP. These study participants may be rescreened after receiving 
prophylaxis treatment. One rescreening may be allowed after consultation with the Medical 
Monitor. Further details are provided in Section 5.4. 
After completion of the Screening Period, eligible study participants will be allowed to enroll 
into the study. Approximately 45 adult Korean study participants will be randomized 2:1 to 
receive the following blinded IMP regimens during the Treatment Period: 
• Bimekizumab 320mg every 4 weeks (Q4W) administered subcutaneous (sc) injection 
(30 study participants) 
• Placebo Q4W administered sc injection (15 study participants) 
During the Treatment Period, IMP will be administered at the study site. 
All study participants choosing not to transition into a managed access program (MAP) (see 
Section 6.8) will have a Safety Follow-Up (SFU) Visit 20 weeks post last dose of IMP. Safety 
assessments will be made by ongoing monitoring and evaluation of adverse events (AEs) and 
other safety topics of interest specific to bimekizumab. 
Study participants withdrawing early from IMP will undergo the Premature End of Treatment 
(PEOT) Visit assessments and be asked to continue in the SFU Period. 
A study participant is considered to have completed the study if he/she has completed the 
Treatment Period of the study (Week 16) regardless of transfer into the MAP or completion of 
the SFU visit (see Section 6.8). 
The end of the study is defined as the date of the last study participant’s last visit (LPLV) in the 
study. 
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Number of participants 
Approximately 45 adult Korean study participants will be randomly assigned to IMP for an 
estimated total of 30 evaluable study participants in the bimekizumab 320mg group and 15 study 
participants in the placebo group. 
Treatment groups and duration 
Study participants will be randomized 2:1 to 2 dose groups; bimekizumab 320mg Q4W or 
placebo. This study will include 3 periods: Screening Period (2 to 5 weeks), Treatment Period 
(16 weeks), and SFU Period (20 weeks after the last dose of IMP). 
 
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1.2 
Schema 
Figure 1-1: Study schematic 
 
IGA= Investigator’s Global Assessment; IMP=investigational medicinal product; MAP=managed access program; PASI=Psoriasis Area and Severity Index; 
PEOT=Premature End of Treatment; Q4W=every 4 weeks; SFU=Safety Follow-Up; W=Week 
a If a participant completes Week16 and is provided the continued treatment with bimekizumab as part of the MAP, SFU is not required. 
 
Screening 
Treatment Period 
Placebo Q4W 
Bimekizumab 320mg Q4W 
SFU Visit 
20 Weeks after 
last dose of IMP  
for each study  
participant 
N=45 
N=15 
N=30 
Baseline/
W16
a 
Visit/Week 
Randomization 
Co-primary Endpoint: 
PASI90 Response and 
IGA Response 
W12 
W4 
W8 
IMP Administration 
X 
X 
X 
X 
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1.3 
Schedule of activities 
Table 1-1: 
Schedule of study assessments 
Visita/ 
Week 
 
Protocol activity 
Screeningb 
Treatment Period 
SFUc 
Baseline 
(W0) 
W1 
W2 
W4 
W8 
W12 
W16/ 
PEOT 
Informed consent 
X 
 
 
 
 
 
 
 
 
Inclusion/exclusion 
X 
X 
 
 
 
 
 
 
 
Urine drug screen 
X 
 
 
 
 
 
 
 
 
Demographic data 
X 
 
 
 
 
 
 
 
 
PSO history 
X 
 
 
 
 
 
 
 
 
Significant past medical history and concomitant 
diseases 
X 
Xd 
 
 
 
 
 
 
 
Physical examination e, f 
X 
X 
 
 
 
 
X 
X 
X 
Height 
 
X 
 
 
 
 
 
 
 
Body weight 
 
X 
 
 
 
 
 
X 
 
Vital signsg 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hematology and biochemistry  
X 
X 
X 
X 
X 
 
X 
X 
X 
Urinalysis 
X 
X 
 
 
 
 
 
X 
X 
ECG 
X 
 
 
 
 
 
 
X 
 
Pregnancy testingh 
X 
X 
 
 
X 
X 
X 
X 
X 
Hepatitis B and C testingi 
X 
 
 
 
 
 
 
 
 
HIV testingj 
X 
 
 
 
 
 
 
 
 
Chest x-rayk 
X 
 
 
 
 
 
 
 
 
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Table 1-1: 
Schedule of study assessments 
Visita/ 
Week 
 
Protocol activity 
Screeningb 
Treatment Period 
SFUc 
Baseline 
(W0) 
W1 
W2 
W4 
W8 
W12 
W16/ 
PEOT 
IGRA TB test 
X 
 
 
 
 
 
 
  
 
TB questionnairel 
X 
X 
 
 
 
 
Xl 
 
X 
PASI 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IGA 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Scalp IGAm 
 
X 
 
X 
X 
X 
X 
X 
X 
Percentage of BSA 
X 
X 
X 
X 
X 
X 
X 
X 
X 
DLQI 
 
X 
 
X 
X 
X 
X 
X 
 
PHQ-9 
X 
X 
 
 
X 
X 
X 
X 
X 
C-SSRS 
X 
X 
 
 
X 
X 
X 
X 
X 
PSD (P-SIM) (daily) 
X 
X 
X 
X 
X 
X 
X 
X 
 
Concomitant medication 
X 
X 
X 
X 
X 
X 
X 
X 
X 
AEs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
IRTn, o 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Blood sample for PK plasma BKZ concentrations 
and anti-BKZ antibodiesp 
 
X 
 
 
X 
X 
X 
X 
X 
BKZ or placebo administrationn,  o 
 
X 
 
 
X 
X 
X 
 
 
AEs=adverse events; BKZ=bimekizumab; BSA=body surface area; DLQI=Dermatology Life Quality Index; ECG=electrocardiogram; eCRF=electronic Case 
Report Form; C-SSRS=Columbia Suicide Severity Rating Scale; HBcAb+=positive for anti-hepatitis B core antibody; HBsAg+=positive for hepatitis B surface 
antigen; HCV=hepatitis C virus; HIV=human immunodeficiency virus; IGA=Investigator’s Global Assessment; IGRA=interferon-gamma release assay; 
IMP=investigational medicinal product; IRT=interactive response technology; MAP=Managed Access Program;  PASI=Psoriasis Area Severity Index; 
PEOT=Premature End of Treatment; PHQ-9=Patient Health Questionnaire-9; PK=pharmacokinetic; PSD=patient symptom diary; P-SIM=Patient Symptom 
and Impact Measure; PSO=psoriasis; SFU=Safety Follow-Up; TB=tuberculosis; W=Week 
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a Visit windows of ±3 days from the first dose (W0) to the Week 16 visit. The SFU Visit window is ±7 days from last dose. 
b 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. 
c For study participants not entering the MAP, the SFU Visit will occur 20 weeks after the final dose of IMP. No SFU will occur for study participants entering 
the MAP. 
d Ensure no significant changes in medical history. 
e Includes evaluation of signs and symptoms of active TB and risk for exposure to TB. 
f The physical examination will be performed as per protocol. 
g Vital signs (sitting systolic and diastolic blood pressure, pulse rate, and body temperature) are to be measured prior to blood sampling, and prior to IMP dosing, 
where applicable. 
h Pregnancy testing will consist of serum testing at Screening. A urine pregnancy test will be administered at all other visits. 
i Study participants who have evidence of or test positive for hepatitis B by any of the following criteria: 1) HBsAg+; 2) 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. Study participants will also be tested for antihepatitis B surface antibody. 
j The HIV test results will not be recorded in the eCRF. 
k Screening chest x-ray must occur within 3 months prior to the Screening Visit. 
l Tuberculosis questionnaire will be required at PEOT. 
m The scalp IGA will only be assessed for those study participants with scalp involvement (scalp IGA score >0) at Baseline. 
n IMP administration is based on randomization. 
o The dosing window is ±3 days relative to the scheduled dosing visit through Week 16. 
p 
Samples will be collected prior to any IMP dosing at a visit. 
q 
If an Unscheduled Visit is conducted due to safety or efficacy reasons, a C-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), a C-SSRS will not be required at these visits. 
 
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2 
INTRODUCTION 
2.1 
Study rationale 
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. 
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 inhibitor apremilast, or biologic agents, such as tumor 
necrosis factor (TNF) antagonists, interleukin (IL)-12/23 inhibitors, IL-23p19 inhibitors, and 
IL-17A inhibitors. 
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). While antibodies targeting IL-17A cytokines 
have demonstrated efficacy in patients with PSO, psoriatic arthritis (PsA), and ankylosing 
spondylitis, as yet, no approved therapeutic approach selectively and potently inhibits the activity 
of both IL-17A and IL-17F (Krueger and Ellis, 2005). 
Bimekizumab is a humanized, full-length monoclonal antibody (mAb) of the immunoglobulin 
G1 (IgG1) subclass with 2 identical antigen binding regions that potently and selectively bind 
and neutralize IL-17A, IL-17F, and IL-17AF cytokines. This property makes bimekizumab 
distinct from other IL-17-targeting agents, like secukinumab and ixekizumab (selective 
anti-IL-17A cytokine-targeting mAbs) or brodalumab (an-IL-17 receptor-targeting mAb). 
Bimekizumab is being developed for the treatment of adults with moderate to severe plaque 
PSO. Parallel programs in the inflammatory diseases of PsA, axial spondyloarthritis, and 
hidradenitis suppurativa are ongoing. 
The purpose of this study is to evaluate the efficacy and safety of bimekizumab in adult Korean 
study participants with moderate to severe plaque PSO. Following the completion of the pivotal 
global Phase 3 program of bimekizumab in moderate to severe PSO, the aim of this study is to 
bridge the existing evidence of efficacy and safety of bimekizumab from the Phase 3 program 
with limited Korean participation to a Korean population of study participants with moderate to 
severe PSO. 
2.2 
Background 
Psoriasis is a common, chronic inflammatory disease characterized by inflammation and 
keratinocyte proliferation. Plaque PSO, the most common form of the disease, is typified by 
areas of red, inflamed skin, often covered with thick, micaceous, silver-colored scales on 
extensor surfaces. Plaques may be pruritic and painful as the skin cracks and bleeds. In severe 
cases, plaques grow and merge into one another, covering large areas. 
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 
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(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, 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). 
The reported prevalence of PSO in countries ranges between 0.09% and 11.43%, with at least 
100 million individuals affected worldwide (WHO report on psoriasis, 2016). There are a variety 
of forms of PSO, including plaque, guttate, inverse, pustular, and erythrodermic. Plaque PSO 
(PSO vulgaris) is the most common, comprising approximately 80% to 90% of all cases. It is 
estimated that approximately 80% of patients with plaque PSO have mild to moderate disease, 
while 20% of patients have more severe disease, which affects either greater than 5% of BSA or 
is located on high impact areas including the scalp, genitals, hands, and nails (Boehncke and 
Schön, 2015; Menter et al, 2008). 
Descriptions of nonclinical and clinical bimekizumab data, including the status of ongoing 
studies, are provided in the current version of the Investigator’s Brochure (IB). 
2.3 
Benefit/risk assessment 
Based on the limited data collected from Korean study participants in the completed Phase 3 
pivotal program, the benefits and risks of bimekizumab administration in adult Korean study 
participants are expected to be similar to results in adult study participants with PSO to date. 
In studies of bimekizumab in moderate to severe PSO, study participants achieved and 
maintained skin clearance across multiple efficacy variables, as assessed by PASI (change from 
Baseline and by various levels of response) and IGA responses, after up to 56 weeks of 
bimekizumab 320mg sc treatment administered Q4W or Q4W for an initial 16 weeks followed 
by every 8 weeks (Q8W) maintenance treatment. The observed safety data were as expected 
considering the mechanism of action of bimekizumab and the population under investigation. 
The vast majority of AEs were nonserious, mild to moderate, and did not lead to IMP 
discontinuation. The most commonly reported TEAEs in bimekizumab-treated study participants 
were nasopharyngitis, oral candidiasis, and upper respiratory tract infection. 
Prespecified safety topics of interest for the study are: infections (serious, opportunistic, fungal, 
and TB), neutropenia, hypersensitivity, suicidal ideation and behavior, major CV events, liver 
function test (LFT) changes/enzyme elevations, malignancies, and inflammatory bowel diseases 
(IBD). This is based on findings from the bimekizumab 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. 
More detailed information about the known and expected benefits and risks and reasonably 
expected AEs of bimekizumab may be found in the IB. 
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3 
OBJECTIVES AND ENDPOINTS 
Objectives 
Endpoints 
Primary 
Co-Primary Endpoints 
To evaluate the efficacy of 
bimekizumab compared with placebo 
Co-Primary Endpoint 1: 
• 
Participant-level outcome: PASI90 response at Week 16 
Co-Primary Endpoint 2: 
• 
Participant-level outcome: IGA 0/1 (clear or almost clear 
with at least a 2-category improvement from Baseline) 
response at Week 16 
Secondary 
To evaluate the efficacy of 
bimekizumab compared with placebo 
at achieving complete skin clearance 
(PASI100/IGA 0) 
• 
Participant-level outcome: PASI100 response at Week 16 
• 
Participant-level outcome: IGA 0 (clear with at least a 
2-category improvement from Baseline) response at 
Week 16 
To evaluate the efficacy of 
bimekizumab compared with placebo 
at achieving rapid response (PASI75) 
• 
Participant-level outcome: PASI75 response at Week 4 
To evaluate the efficacy of 
bimekizumab compared with placebo 
on itch, pain, and scaling 
Reported by study participants using the PSD (also published 
as P-SIM [Gottlieb et al, 2020]): 
• 
Participant-level outcome: PSD (P-SIM) response for itch 
at Week 16 
• 
Participant-level outcome: PSD (P-SIM) response for pain 
at Week 16 
• 
Participant-level outcome: PSD (P-SIM) response for 
scaling at Week 16 
To evaluate the efficacy of 
bimekizumab compared with placebo 
on the change in psoriatic scalp 
disease in study participants with 
scalp PSO at Baseline 
• 
Participant-level outcome: Scalp IGA 0/1 (clear or almost 
clear with at least a 2-category improvement from 
Baseline) response at Week 16 for study participants with 
scalp PSO at Baseline 
To assess the effect of bimekizumab 
compared with placebo on QOL 
• 
Participant-level outcome: DLQI 0/1 response at Week 16 
To evaluate the effect of 
bimekizumab compared with placebo 
on percent change from Baseline in 
BSA affected by PSO 
• 
Participant-level outcome: Percent change from Baseline 
in BSA affected by PSO at Week 16 
To evaluate the safety of 
bimekizumab 
• 
Incidence of TEAEs throughout the study 
• 
Incidence of TE-SAEs throughout the study 
• 
Incidence of TEAEs leading to permanent discontinuation 
of IMP throughout the study 
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Objectives 
Endpoints 
To assess the effect of bimekizumab 
on depression occurrence or 
worsening 
• 
Change from Baseline in PHQ-9 at Week 16 
Tertiary 
To evaluate the PK of bimekizumab 
in study participants with moderate to 
severe PSO 
• 
Plasma bimekizumab concentrations over the study 
duration 
To evaluate the immunogenicity of 
bimekizumab 
• 
Anti-bimekizumab antibody status over the study duration 
To assess the efficacy of 
bimekizumab compared with placebo 
over time 
• 
PASI75 response over time 
• 
PASI90 response over time 
• 
PASI100 response over time 
• 
Absolute and percent change from Baseline in PASI score 
over time 
• 
Percentage of study participants with absolute PASI score 
≤1, ≤2, ≤3, and ≤5 over time 
• 
Time to PASI50, PASI75, PASI90, and PASI100 
response 
• 
IGA 0/1 response (with at least 2-category improvement 
from Baseline) over time 
• 
IGA 0 response (with at least 2-category improvement 
from Baseline) over time 
• 
Scalp-specific IGA (scalp IGA) 0/1 response (clear or 
almost clear with at least 2-category improvement from 
Baseline for participants with scalp PSO at Baseline) over 
time 
• 
Percentage of study participants with absolute BSA 
affected by PSO=0%, ≤1%, ≤3% and ≤5% over time 
• 
Percentage of study participants achieving a DLQI Total 
Score of 0 or 1 over time 
• 
Change from Baseline in DLQI Total Score over time 
• 
PSD (P-SIM) response rates over time 
• 
Change from Baseline in PSD (P-SIM) scores over time 
To further evaluate the safety of 
bimekizumab compared with placebo 
over time 
• 
Selected safety topics of interest TEAEs 
• 
Change from Baseline in laboratory variables 
(hematology and biochemistry) 
• 
Incidence of markedly abnormal laboratory values 
• 
Change from Baseline in vital signs 
• 
Incidence of markedly abnormal vital signs 
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Objectives 
Endpoints 
• 
Change from Baseline in ECG parameters 
• 
ECG outliers 
• 
Change from Baseline in PHQ-9 
• 
Incidence of PHQ-9 scores ≥15 and ≥20 
• 
Incidence of suicidal ideation, suicidal behavior, or self-
injurious behavior without suicidal intent (from C-SSRS) 
4 
STUDY DESIGN 
4.1 
Overall design 
PS0032 is a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel group 
study to evaluate the efficacy and safety of bimekizumab compared with placebo in adult Korean 
study participants with moderate to severe plaque PSO. 
The study population consists of adult Korean study participants (≥19 years of age) with a 
diagnosis of moderate to severe plaque 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. 
This study will include 3 periods: Screening Period (2 to 5 weeks), Treatment Period (16 weeks), 
and SFU Period (20 weeks after the last dose of IMP [Figure 1-1]).  
Study participants who have completed the 16-week Treatment Period may choose to enter into a 
MAP to receive open-label treatment with bimekizumab or enter the SFU. 
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 the Screening Period, eligible study participants will be informed about the 
study and sign the ICF. Following signed informed consent, all screening procedures and 
laboratory tests (hematology, urine, and biochemistry) will be performed per the SoA 
(Table 1-1). The Screening Period will also enable washout of any medications not permitted for 
use during the study. Study participants who require prophylaxis for LTB infection must be on 
treatment for at least 4 weeks prior to the first dose of IMP. These study participants may be 
rescreened after receiving prophylaxis treatment. One rescreening may be allowed after 
consultation with the Medical Monitor. Further details are provided in Section 5.4. 
After completion of the Screening Period, eligible study participants will be allowed to enroll 
into the study. Approximately 45 adult Korean study participants will be randomized 2:1 to 
receive the following blinded IMP regimens during the Treatment Period: 
• Bimekizumab 320mg Q4W administered sc injection (30 study participants) 
• Placebo Q4W administered sc injection (15 study participants) 
During the Treatment Period, IMP will be administered at the study site. 
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All study participants choosing not to transition into a MAP (see Section 6.8) will have a SFU 
Visit 20 weeks post last dose of IMP. Safety assessments will be made by ongoing monitoring 
and evaluation of AEs and other safety topics of interest specific to bimekizumab. 
Study participants withdrawing early from IMP will undergo the PEOT Visit assessments and be 
asked to continue in the SFU Period. 
IMP administration and all assessments to be performed during the study are presented in the 
SoA (Table 1-1). 
4.2 
Scientific rationale for study design 
This bimekizumab Phase 3 local clinical study in Korean study participants with PSO is designed 
to support a bridging data submission package for approval of the PSO indication in Korea. 
Previously it was demonstrated in a dedicated Phase 1 PK study (UP0042) that the PK/PD 
profile of Caucasian and Asian study participants is largely comparable. In addition, subgroup 
analyses of the Phase 2 (PS0010 and PS0011) and Phase 3 (PS0009) PSO studies have indicated 
that results of the Asian population were comparable to those of the overall population. 
Population PK/PD analyses revealed a clear dose-response relationship and support the use of 
bimekizumab at an initial dose regimen of 320mg Q4W to ensure rapid and high skin clearance, 
followed by a less intense dose regimen (320mg Q8W) in the majority of study participants to 
maintain these initial responses beyond Week 16. 
The clinical response obtained in the global PSO development program (PS0008, PS0009, and 
PS0013) at Week 16 was consistently maintained through one year in study participants 
receiving either bimekizumab 320mg Q4W or bimekizumab 320mg Q8W, supporting the 
rationale for a 16-week study. This study aims to demonstrate the superiority of clinical response 
to bimekizumab over placebo in Korean study participants to those of the overall population 
during the initial Treatment Period of 16 weeks, allowing for adequate extrapolation of results in 
the maintenance period. 
4.3 
Justification for dose 
Bimekizumab 320mg Q4W treatment effects in the initial 16-week treatment period were rapid 
(PASI75 achieved after a single dose) and deep (complete PSO clearance demonstrated by 
PASI100 and IGA 0). Approximately 85% to 90% of study participants achieved a high level of 
response (PASI90) after 16 weeks of bimekizumab 320mg Q4W treatment. 
Study PS0032 has been designed to mimic the initial Treatment Period of the 3 global Phase 3 
studies (PS0008, PS0009, and PS0013) and evaluate the efficacy and safety of bimekizumab 
320mg, administered sc Q4W, in Korean study participants to allow bridging to the global 
Phase 3 data. 
4.4 
End of study definition 
A study participant is considered to have completed the study if he/she has completed the 
Treatment Period of the study (Week 16) regardless of transfer into the MAP or completion of 
the SFU visit (see Section 6.8). 
The end of the study is defined as the date of the LPLV in the study. 
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5 
STUDY POPULATION 
Prospective approval of protocol deviations to recruitment and enrollment criteria, also known as 
protocol waivers or exemptions, is not permitted. 
5.1 
Inclusion criteria 
Study participants are eligible to be included in the study only if all of the following criteria are 
met at Screening and reconfirmed at the Baseline Visit: 
Age 
1. Study participant must be at least 19 years of age at the time of signing the informed consent. 
Type of participant and disease characteristics 
2. Study participant must be a Korean adult with a diagnosis of moderate to severe PSO.  
3. Study participant must have had plaque PSO for at least 6 months prior to the Screening 
Visit. 
4. Study participant must have PASI ≥12 and BSA affected by PSO ≥10% and IGA score ≥3 on 
a 5-point scale. 
5. Study participant must be a candidate for systemic PSO therapy and/or phototherapy. 
6. Study participant 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. 
7. Study participant 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. 
Sex 
8. A female study participant is eligible to participate if she is not pregnant (see Section 10.4 
[Appendix 4]), not breastfeeding, and at least one of the following conditions applies: 
− Not a female of childbearing potential (FOCBP) as defined in Section 10.4 (Appendix 4) 
OR 
A FOCBP who agrees to follow the contraceptive guidance in Appendix 4 during the 
Treatment Period and for at least 20 weeks after the last dose of study treatment. 
Informed consent 
9. Study participant must be capable of giving signed informed consent as described in 
Section 10.1 (Appendix 1), which includes compliance with the requirements and restrictions 
listed in the ICF and in this protocol. 
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5.2 
Exclusion criteria 
Study participants are excluded from the study if any of the following criteria apply: 
Medical conditions 
1. Study participant has a form of PSO other than plaque-type (eg, pustular, erythrodermic and 
guttate PSO, or drug-induced PSO). 
2. Study participant has an active infection or history of infections as follows: 
− Any active infection (except common cold) within 14 days prior to Baseline. 
− A serious infection, defined as requiring hospitalization or intravenous anti-infectives 
within 2 months prior to the Baseline Visit. 
− A history of opportunistic, recurrent, or infections that, in the opinion of the Investigator, 
might cause this study to be detrimental to the study participants. Opportunistic infections 
are infections caused by uncommon pathogens (eg, pneumocystis jirovecii, 
cryptococcosis) or unusually severe infections caused by common pathogens (eg, 
cytomegalovirus, herpes zoster). 
3. Study participant has concurrent acute or chronic viral hepatitis B or C or human 
immunodeficiency virus (HIV) infection, or history of hepatitis B. Study participants who 
have evidence of, or tested positive for hepatitis B are excluded. A positive test for the 
hepatitis B virus (HBV) is defined as: 
− positive for hepatitis B surface antigen (HBsAg+) or 
− positive for anti-hepatitis B core antibody (HBcAb+). 
A positive test for the hepatitis C virus (HCV) is defined as: 
− positive for hepatitis C antibody (anti-HCV Ab) and 
− positive via a confirmatory test for HCV (eg, HCV polymerase chain reaction). 
4. Study participant has a known tuberculosis (TB) infection, is at high risk of acquiring a TB 
infection, or has a current or history of nontuberculous mycobacterium (NTMB) infection. A 
study participant with LTB (a positive interferon-gamma release assay [IGRA] and diagnosis 
confirmed by a TB specialist) may be rescreened once and enrolled after receiving at least 
4 weeks of appropriate LTB infection therapy and if no evidence of therapy-related 
hepatotoxicity has occurred prior to the first injection (alanine aminotransferase/aspartate 
aminotransferase [ALT/AST] remain ≤3×upper limit of normal [ULN]). 
Study participant has a past history of active TB involving any organ system unless 
adequately treated according to World Health Organization (WHO)/Centers for Disease 
Control (CDC) therapeutic guidance and proven to be fully recovered upon consult with a TB 
specialist. 
5. Study participant has a history of a lymphoproliferative disorder, including lymphoma, or 
current signs and symptoms suggestive of lymphoproliferative disease. 
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6. Study participant 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. 
7. Study participant has a diagnosis of inflammatory conditions other than PSO or PsA, 
including but not limited to rheumatoid arthritis, sarcoidosis, or systemic lupus 
erythematosus. Study participants 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. 
8. Study participant has any systemic disease (ie, CV, 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. 
9. Study participant has had myocardial infarction or stroke within the 6 months prior to the 
Screening Visit. 
10. Study participant 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. 
11. Study participant has a history of 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. 
12. Study participant has a presence of active suicidal ideation, or positive suicidal behavior 
using the Columbia Suicide Severity Rating Scale (C-SSRS) and with either of the following 
criteria: 
− History of a suicide attempt within the 5 years prior to the Screening Visit. Study 
participants 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 as indicated by a positive response ("Yes") to either 
Question 4 or Question 5 of the C-SSRS. 
13. Study participant has a presence of moderately severe major depression or severe major 
depression indicated by a score ≥15 using the Screening PHQ-9. Medication used to treat 
depression should be stable for 8 weeks prior to Baseline. 
14. Study participant has a known hypersensitivity to any excipients of bimekizumab. 
15. Study participant has any other condition, including medical or psychiatric, which, in the 
Investigator's judgment, would make the study participant unsuitable for inclusion in the 
study. 
Prior/concomitant therapy  
16. Study participant 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). Live vaccines are not allowed during the 
study, including the SFU Period (20 weeks after the final dose of IMP). 
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Administration of any other type of vaccine that is not a live or inactivated vaccine must be 
discussed with the study Medical Monitor or UCB Study Physician. 
17. Study participant has received Bacillus Calmette-Guerin vaccinations within 1 year prior to 
the Baseline visit. 
18. Study participant has had major surgery (including joint surgery) within the 3 months prior to 
the Baseline Visit or has planned major surgery within the duration of the study. 
19. Study participant is taking or has taken prohibited PSO medications (Section 6.5.2) without 
meeting the mandatory washout period relative to the Baseline Visit. 
Prior/concurrent clinical study experience 
20. Study participant previously participated in a bimekizumab clinical study and received at 
least 1 dose of the IMP (including placebo). 
21. Study participant 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. 
22. Study participant 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. 
23. Study participant 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. 
Diagnostic assessments 
24. Study participant has laboratory abnormalities at Screening, including any of the following: 
− ≥3×ULN of any of the following: ALT, AST, alkaline phosphatase (ALP); or >ULN total 
bilirubin (≥1.5×ULN total bilirubin if known Gilbert’s syndrome) 
− White blood cell (WBC) count <3.00×103/μL 
− Absolute neutrophil count <1.5×103/μL 
− Lymphocyte count <500cells/μL 
− Hemoglobin <8.5g/dL 
− Any other laboratory abnormality, which, in the opinion of the Investigator, will prevent 
the study participant 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, study participants whose results remain outside this threshold 
should not be randomized. 
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Other exclusions 
25. Study participant 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. 
26. Study participant is a UCB employee or an employee of third-party organizations involved in 
the study. 
5.3 
Lifestyle restrictions 
Study participant agrees not to change his/her usual sun exposure during the course of the study 
and to use ultraviolet A/ultraviolet B sunscreens if unavoidable exposure occurs. 
5.4 
Screen failures 
Screen failures are defined as study participants who consent to participate in the clinical study 
but are not subsequently randomized to study treatment. A minimal set of screen failure 
information is required to ensure transparent reporting of screen failure study participants to 
meet the Consolidated Standards of Reporting Trials (CONSORT) publishing requirements and 
to respond to queries from regulatory authorities. Minimal information includes demography, 
screen failure details, eligibility criteria, and any SAE. 
One rescreening may be allowed after consultation with the Medical Monitor. Rescreened study 
participants should be assigned a new study participant number. Reasons for rescreening include, 
but are not limited to, the following: 
• Study participant needs to complete a full course of antibiotic therapy for latent tuberculosis 
infection (LTBI) and can be rescreened after completion of 4 weeks of prophylaxis  prior to 
Baseline as described in the exclusion criteria (Section 5.2). 
• Individual laboratory screening tests for which the results are exclusionary can be retested. 
For example, tests that result in ALT, AST, or ALP up to 25% above the exclusion limit may 
be repeated once for confirmation; however, the Investigator will need to discuss with the 
Medical Monitor to help understand the elevation before the study participant can be 
enrolled. Tests can also be repeated during rescreening. Repetition of laboratory screening 
tests within the Screening Period for other than technical reasons (eg, frozen sample, expired 
laboratory kit) may not be performed without approval by Medical Monitor. 
• Eligibility assessments could not be completed as planned (eg, for technical reasons) within 
the defined Screening Period of 5 weeks without approval by Medical Monitor. 
• Participant does not meet the required washout period for concomitant medications 
(Section 6.5.2). 
For randomized study participants with a Baseline result >ULN for ALT, AST, ALP, or total 
bilirubin, a Baseline diagnosis and/or the cause of any clinically meaningful elevation must be 
understood and recorded in the electronic Case Report form (eCRF). 
If a participant has >ULN ALT, AST, or ALP that does not meet the exclusion limit at screening, 
repeat the tests, if possible, prior to dosing to ensure there is no further ongoing clinically 
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relevant increase. In case of a clinically relevant increase, inclusion of the study participant must 
be discussed with the Medical Monitor. 
6 
STUDY TREATMENTS 
6.1 
Treatments administered 
Eligible study participants will be randomized 2:1 to receive the blinded study treatment 
regimens: bimekizumab 320mg Q4W or placebo (Table 6-1). Suitable areas for sc injections are 
the lateral abdominal wall, upper arm, 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. 
Further details of the IMPs and their specifications are provided in the IMP Handling Manual. 
Table 6-1: 
Treatments administered 
ARM Name 
Bimekizumab 
Placebo 
IMP name 
Bimekizumab 320mg Q4W 
Placebo 
Type 
Biologic 
N/A 
Dose formulation 
1mL PFS 
1mL PFS 
Unit dose strength(s) 
160mg/mL 
0.9% sodium chloride aqueous 
solution (physiological saline, 
preservative-free) of pharmacopoeia 
(USP/Ph.Eur) quality 
Dosage level(s) 
320mg Q4W 
Placebo Q4W 
Route of 
administration 
sc injection 
sc injection 
Use 
Bimekizumab = active 
Placebo comparator 
IMP  
IMP 
IMP 
Sourcing 
Provided centrally by the Sponsor  
Provided centrally by the Sponsor 
Packaging and 
labeling 
Each PFS will be labeled as required 
by Korea. 
Each PFS will be labeled as required 
by Korea. 
Former name 
UCB4940 
N/A 
IMP=investigational medicinal product; N/A=not applicable; PFS=prefilled syringe; Ph.Eur=European 
Pharmacopoeia; Q4W=every 4 weeks; sc=subcutaneous; USP=United States Pharmacopoeia 
6.2 
Preparation, handling, storage, and accountability requirements 
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 
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assuring the medication is taken from the correct kit and administering the IMP to the study 
participants. 
Only study participants enrolled in the study may receive IMP, and only authorized site staff may 
supply or administer IMP. All IMP must be stored in a secure, environmentally controlled, and 
monitored (manual or automated) area in accordance with the labeled storage conditions, with 
access limited to the Investigator and authorized site staff. 
The Investigator, institution, or the head of the medical institution (where applicable) is 
responsible for IMP accountability, reconciliation, and record maintenance (ie, receipt, 
reconciliation, and final disposition records). 
The Investigator or designee must confirm appropriate temperature conditions have been 
maintained during transit for all IMP received and any discrepancies are reported and resolved 
before use of the IMP. 
In case an out-of-range temperature is noted, it must be immediately reported as per instructions 
contained in the IMP Handling Manual. 
Further guidance and information for the final disposition of unused IMP are provided in the 
IMP Handling Manual. 
6.2.1 
Drug accountability 
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. 
The Drug Accountability Form will be used to record IMP dispensing and return information on 
a by-participant basis and will serve as source documentation during the course of the study. 
Details of any IMP lost, damaged (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 open-label 
packaging, the unblinded study staff will be responsible in order to maintain 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 IMP 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. 
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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, or returned to UCB (or designee). IMP intended for the study cannot be used for any 
other purpose than that described in this protocol. 
6.3 
Measures to minimize bias: randomization and blinding 
An IRT will be used for assigning eligible study participants to a treatment regimen (as 
applicable) 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 kits of IMP, as appropriate, according 
to the visit schedule. 
At Screening, each study participant will be assigned a 5-digit number that serves as the study 
participant identifier throughout the study. The study participant number will be required in all 
communication between the Investigator or designee and the IRT regarding a particular 
participant. 
At the Baseline Visit, a study participant 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 study participant’s identification number. The IRT will allocate kit numbers to 
the study participant based on the study participant number during the course of the study. 
Study participant numbers and kit numbers will be tracked via the IRT. 
6.3.1 
Procedures for maintaining and breaking the treatment blind 
6.3.1.1 
Maintenance of study treatment blind 
All study participant treatment details (bimekizumab or placebo) will be allocated and 
maintained by the IRT system. 
In order to maintain the blind, all IMP documentation (eg, shipping receipts, drug accountability 
logs, 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 Korea guidelines) to administer injections. 
Unblinded study staff will be delegated the responsibility to receive, inventory, and destroy the 
used IMP. The packaging identifies each kit by a unique number. Unblinded study staff will be 
responsible for preparation (breaking tamper proof sticker on kit, etc.) of the IMP, including 
recording the administration information on source documents. 
6.3.1.2 
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 study participant cannot be 
made without knowing the treatment assignment, it will be possible to determine to which 
treatment arm and dose the study participant 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. 
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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. 
6.4 
Treatment 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. 
If a study participant is noncompliant with the study procedures or medications, in the opinion of 
the Investigator, then the study participant should be withdrawn as described in Section 7.2. 
6.5 
Concomitant medications/treatments 
Any medications/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. 
6.5.1 
Permitted concomitant treatments (medications and therapies) 
The following concomitant medications are permitted during the study: 
• Study participants may continue to use topical moisturizers or emollients, bath oils, or 
oatmeal bath preparations for skin conditions during the study, as needed (PRN). 
• Mild and low potency topical steroids will be permitted for use limited to the face, axilla, 
and/or genitalia, PRN. These topical medications should not be used within approximately 
24 hours prior to study visits requiring IGA and PASI measures. 
• Over-the-counter shampoos for the treatment of PSO of the scalp are permitted PRN. If this 
treatment contains a corticosteroid, it must adhere to the guidance for topical corticosteroids 
outlined in the above bullet. 
• Study participants who are receiving an established regimen for depression should remain on 
stable dosing prior to Baseline and throughout the study. Medication used to treat depression 
should be stable for 8 weeks prior to Baseline. 
• Study participants who are already receiving an established nonsteroidal anti-inflammatory 
drug (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 study 
participants with a history of gastrointestinal (GI) intolerance to NSAIDs or a history of GI 
ulceration) should not occur prior to Week 16. 
• Study participants may take mild pain relievers (acetaminophen/paracetamol, mild opiates) 
PRN for arthritis pain but preferably not within 24 hours of the Baseline Visit and the 
Week 16 Visit. 
• Intra-articular steroid injections of any joint and hyaluronic acid injections are allowed after 
Week 16. 
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6.5.2 
Prohibited concomitant treatments (medications and therapies) 
For prohibited prior medications, refer to the exclusion criteria (Section 5.2). 
The following concomitant medications and therapies are prohibited during the study: 
Drug 
Washout period relative to Baseline Visit 
Topicals, except for those permitted 
2 weeks 
Systemic retinoids 
1 month 
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: 
etanercept (including biosimilar) 
infliximab (including biosimilar), golimumab, 
certolizumab pegol, adalimumab 
 
1 month for etanercept 
3 months for infliximab (including biosimilar), 
golimumab, certolizumab pegol, adalimumab 
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 
Any other antipsoriatic agent (topical) under 
investigation 
1 month 
IL-17=interleukin 17; PSO=psoriasis; TNF=tumor necrosis factor 
Study participants who take prohibited medications may be withdrawn from IMP but followed 
until the SFU Visit. The decision to withdraw a study participant for taking prohibited 
medications should be made in consultation with the Medical Monitor. 
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6.5.3 
Vaccines 
Administration of live (including attenuated) vaccines is not allowed during the conduct of the 
study and for 20 weeks after the last dose of IMP. Administration of inactivated vaccines is 
allowed during the study at the discretion of the Investigator in consultation with the Medical 
Monitor or UCB Study Physician. 
Administration of any other type of vaccine that is not a live or inactivated vaccine must be 
discussed with the Medical Monitor or UCB Study Physician. 
6.5.4 
Rescue medication 
No rescue medication is planned. 
6.6 
Dose modification 
No dose modifications are allowed during the Treatment Period. 
6.7 
Criteria for study hold or dosing stoppage 
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 Institutional Review Board (IRB)/Independent Ethics Committee (IEC) 
should also be informed and provided with the 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 or destruction of all unused 
IMP and other material in accordance with UCB procedures for the study. 
6.8 
Treatment after the end of the study 
Study participants who have completed the 16-week Treatment Period may choose to enter into a 
MAP to receive open-label treatment with bimekizumab or enter the SFU. 
7 
DISCONTINUATION OF IMP AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL 
7.1 
Discontinuation of IMP 
A study participant should be withdrawn from IMP and will be asked to come back for the SFU 
Visit 20 weeks after last dose of IMP if any of the following events occur: 
1. Study participant develops an illness that in the opinion of the Investigator would interfere 
with his/her continued participation if the risk of continuing participation outweighs the 
potential benefit. 
2. Study participant develops erythrodermic, guttate, or pustular form of PSO. 
3. Study participant is noncompliant with the study procedures or medications in the opinion of 
the Investigator. 
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4. Study participant uses prohibited concomitant medications, with the exception of topicals, 
that may present a risk to the safety of the study participant or the integrity of the study data, 
in the opinion of the Investigator and/or the Medical Monitor. 
5. Study participant has a clinical laboratory value meeting any of the following criteria: 
− Hepatotoxicity as described in Section 7.1.1. 
− A laboratory value meeting any of the following criteria: 
◦ 
Absolute neutrophil count <1.0×103/μL 
◦ 
Absolute lymphocyte count <0.2×103/μL 
Study participants 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 study participant 
must be withdrawn. If the repeat absolute neutrophil count or absolute lymphocyte count is 
above the allowable values, the study participant may continue in the study. 
6. The study participant 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 IMP 
and appropriate measures being taken. 
7. There is confirmation of a pregnancy during the study, as evidenced by a positive pregnancy 
test. Study participants with confirmed pregnancy must discontinue IMP and should remain 
in the study for safety follow-up (see Section 8.2.8.5). 
8. A study participant considered as having either a suspected new LTBI or who develops an 
active TB or NTMB infection during the study 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 study participant must be permanently withdrawn if further examinations result in a 
diagnosis of active TB, or if the study participant is diagnosed with 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 8.2.7. 
9. Study participants with newly diagnosed IBD or 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 study participant should continue in the 
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study and contact the Medical Monitor and UCB Study Physician to confirm the study 
participant´s suitability for continued participation in the study. 
10. Study participants 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 C-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. 
11. Study participants must be referred immediately to a mental health care professional and 
must be withdrawn from the study in case of: 
− Active suicidal ideation as indicated by a positive response (“Yes”) to Question 5 of the 
“Since Last Visit” version of the C-SSRS. 
− Any suicidal behavior since last visit. 
− Severe major depression as indicated by a PHQ-9 score ≥20. 
Study participants must be referred immediately to a mental health care professional for further 
assessment of any suicidal ideation/behavior (SIB) and/or any evidence of major depression. 
Investigators should contact the Medical Monitor, whenever possible, to discuss the withdrawal 
of a study participant in advance. Withdrawal is mandatory for suicidal behavior and/or a 
confirmed diagnosis of severe major depression. Otherwise, a withdrawal decision will be based 
on the Investigator’s assessment of benefit/risk. The mental health consultation will be 
documented in source documentation. 
7.1.1 
Potential drug-induced liver injury IMP discontinuation criteria 
Study participants 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 study 
participants with either of the following: 
• ALT or AST ≥8×ULN 
• ALT or AST ≥3×ULN and coexisting total bilirubin ≥2×ULN 
The PDILI criterion below requires immediate discontinuation of IMP for: 
• Study participants with ALT or AST ≥3×ULN who exhibit temporally associated symptoms 
of hepatitis or hypersensitivity. Hepatitis symptoms include fatigue, nausea, vomiting, and 
right upper quadrant pain or tenderness. Hypersensitivity symptoms may include fever 
(without clear alternative cause), rash, or eosinophilia (ie, >5%). 
If a nondrug-related cause for the symptoms can be confirmed, these study participants may 
resume IMP administration after discussion with the responsible UCB Study Physician, but 
only when the requirements for rechallenge with IMP as provided in Section 10.6.2.1 are 
followed. 
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The PDILI criterion below allows for study participants to continue on IMP at the discretion of 
the Investigator. 
• Study participants with ALT or AST ≥5×ULN and <8×ULN, total bilirubin <2×ULN, 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 10.6.3, with repeat tests performed 
in 2 weeks. Upon retest, if ALT or AST values have reduced to <5×ULN, the study participant 
can continue with the study. However, if ALT or AST remains ≥5×ULN and <8×ULN after 
retest, IMP should be temporarily withheld and study participant should undergo a repeat test in 
two weeks. If ALT or AST values remain ≥5×ULN even after the second retest, then the study 
participant should be permanently withdrawn from the study and should be followed for possible 
drug-induced liver injury. 
If study participants are unable to comply with the applicable monitoring schedule, IMP must be 
discontinued immediately. 
Investigators should attempt to obtain information on study participants in the case of IMP 
discontinuation to complete the final evaluation. Study participants 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 study 
participant withdrawal (if applicable), must be recorded in the source documents. The eCRF 
must document the primary reason for IMP discontinuation. 
7.1.1.1 
Follow-up evaluation 
Potential drug-induced liver injury events require follow-up monitoring as described in 
Table 10-2. 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. 
7.1.2 
Clinical laboratory criteria 
Study participants should be monitored for absolute neutrophil count and/or absolute lymphocyte 
count as described in Section 7.1. 
7.1.3 
Treatment interruptions/temporary discontinuation of IMP 
Doses of IMP that were missed due to a reasonable interfering AE or exceptional circumstance, 
which do not allow administration of IMP due to safety reasons, will not result in the study 
participant being considered noncompliant. The AE or exceptional circumstance should be 
discussed immediately with the Medical Monitor. 
Any considerations related to restarting IMP should be discussed with the Medical Monitor. 
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 participants 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. 
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After implementation of such measure, the Investigator must notify the CPM of the Sponsor 
within 24 hours and follow any local regulatory requirements. 
Any participant who develops a clinically important infection or recurrent infection not 
responsive to standard therapy during the study must discontinue IMP until resolution of the 
infection. The Investigator should use clinical judgement in deciding whether the participant 
should restart IMP, and contact the Medical Monitor and UCB study physician to confirm the 
participant’s suitability for continued participation in the study.  
7.2 
Participant discontinuation/withdrawal from the study 
If a study participant is unable to attend a visit due to the COVID-19 pandemic, study specific 
contingencies will be followed and the study participant should not be withdrawn. 
Study participants are free to withdraw from the study at any time, without prejudice to their 
continued care. 
Study participants should be withdrawn from the study and will be encouraged to come back for 
the SFU Visit 20 weeks after last dose of IMP if the study participant withdraws his/her consent 
or the Sponsor or a regulatory agency requests withdrawal of the study participant. 
A study participant may withdraw from the study at any time at his/her own request, or may be 
withdrawn at any time at the discretion of the Investigator for safety, behavioral, compliance, or 
administrative reasons. 
If the study participant withdraws consent for disclosure of future information, the Sponsor may 
retain and continue to use any data collected before such a withdrawal of consent. 
If a study participant withdraws from the study, he/she may request destruction of any samples 
taken and not tested, and the Investigator must document this in the site study records. 
See the SoA for data to be collected at the time of study discontinuation, follow-up, and any 
further evaluations that need to be completed (Table 1-1). 
Refer to Section 7.1 for additional participant discontinuation/withdrawal criteria. 
7.3 
Lost to follow up 
A study participant will be considered lost to follow-up if he or she repeatedly fails to return for 
scheduled visits and is unable to be contacted by the study site. 
The following actions must be taken if a study participant fails to return to the clinic for a 
required study visit: 
• The site must attempt to contact the study participant and reschedule the missed visit as soon 
as possible, counsel the study participant on the importance of maintaining the assigned visit 
schedule, and ascertain whether or not the study participant wishes to and/or should continue 
in the study. 
• Before a study participant is deemed lost to follow up, the Investigator or designee must 
make every effort to regain contact with the study participant (at least 1 phone call and 
1 written message to the study participant), 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 
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description of the reason(s) for removing the study participant, must be recorded in the 
source documents. The eCRF must document the primary reason for withdrawal. 
Should the study participant continue to be unreachable, he/she will be considered to have 
withdrawn from the study with a primary reason of lost to follow up documented in the eCRF. 
8 
STUDY ASSESSMENTS AND PROCEDURES 
Study procedures and their timing are summarized in the SoA (Table 1-1). 
Some study-specific investigations may not be possible to be conducted according to the study 
protocol during a pandemic or other exceptional circumstances (eg, hurricanes) due to the need 
to implement safety measures and guidance from regulatory authorities. In such a situation, 
which may be accompanied by local or global containment or other measures, sites may need to 
prohibit access to study participants and study-related personnel. Study participants’ visits to the 
study site may be replaced by contingency measures. These measures are primarily established to 
ensure the continued safety of study participants during the course of the study and to maintain 
the study participants’ treatment schedule; if the Investigator considers it appropriate. The 
contingency measures will be described in a contingency plan which will be maintained by UCB 
for the respective study. The contingency measures are shared with the Investigator and the 
respective study-related personnel as soon as there are indications that it is necessary to 
implement any of the measures. 
Protocol waivers or exemptions are not allowed. 
Immediate safety concerns should be discussed with the Sponsor immediately upon occurrence 
or awareness to determine if the study participant should continue or discontinue IMP. 
Adherence to the study design requirements, including those specified in the SoA, is essential 
and required for study conduct. 
All screening evaluations must be completed and reviewed to confirm that potential study 
participants meet all eligibility criteria at the Baseline Visit for randomization. The Investigator 
will maintain a screening log to record details of all participants screened and to confirm 
eligibility or record reasons for screening failure, as applicable. 
Procedures conducted as part of the study participant’s routine clinical management (eg, blood 
count) and obtained before signing of the ICF may be utilized for Screening or Baseline purposes 
provided the procedures met the protocol-specified criteria and were performed within the time 
frame defined in the SoA (Table 1-1). 
Repeat or unscheduled samples may be taken for safety reasons or for technical issues with the 
samples. 
8.1 
Efficacy assessments 
8.1.1 
PASI 
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 PASI will be completed by the 
Investigator electronically at the visits specified in the SoA (Table 1-1). 
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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 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 8‒1). 
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 8‒1: 
Body areas for calculation of percent BSA for PASI 
Body area 
Details of area 
BSA 
Degree of 
involvement of 
body areaa 
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. 
8.1.2 
IGA 
A static IGA for PSO will be used to assess disease severity in all study participants during the 
study. The IGA will be completed at the visits specified in the SoA (Table 1-1). 
The Investigator will assess the overall severity of PSO using the following 5-point scale 
presented in Table 8-2 below. 
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Table 8-2: 
Five-point IGA 
Score 
Short descriptor 
Detailed descriptor 
0 
Clear 
No signs of PSO; postinflammatory 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 
8.1.3 
DLQI 
The DLQI is a questionnaire designed for use in adult study participants with PSO. The DLQI is 
a skin disease-specific questionnaire aimed at the evaluation of how symptoms and treatment 
affect study participants’ health related QOL. This instrument asks study participants about 
symptoms and feelings, daily activities, leisure, work and school, personal relationships, and 
treatment. It has been shown to be valid and reproducible in study participants 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 
study participant (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 (Basra et al, 2015; 
Hongbo et al, 2005). Study participants will be asked to complete the DLQI as outlined in the 
SoA (Table 1-1). 
8.1.4 
Scalp IGA 
A static IGA for scalp PSO will be used to assess disease severity on the scalp. 
The scalp IGA will be assessed for all study participants at Baseline. The scalp IGA will be 
completed by the Investigator electronically. Only study participants with a scalp IGA score >0 
at Baseline will have the scalp IGA assessed at later visits as specified in the SoA (Table 1-1). 
Scalp lesions will be assessed in terms of clinical signs of redness, thickness, and scaliness using 
a 5-point scale (Table 8-3). 
Table 8-3: 
Scalp IGA 
Score 
Short descriptor 
Detailed descriptor 
0 
Clear 
Scalp has no signs of PSO; postinflammatory 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 
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Table 8-3: 
Scalp IGA 
Score 
Short descriptor 
Detailed descriptor 
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 
8.1.5 
PSD (P-SIM) responses 
UCB developed a new electronic patient-reported outcome (ePRO) measure that will be used to 
assess key symptoms relevant to study participants with moderate to severe plaque PSO. PS0010 
used the draft ePRO measure in selected countries to enable psychometric validation of the 
ePRO. 
The PSD (P-SIM) consists of 14 items, measuring the following PSO-related signs, symptoms, 
and functional impacts: redness, scaling, cracking, lesions, thickening, itch, pain, burning, 
dryness, irritation, sensitivity, fatigue, embarrassment, and choice of clothing. Each item is 
assessed for severity/impact level over a recall period of the past 24 hours on a 0 to10 scale, 
where 0 means no symptoms or impact and 10 means very severe symptoms or worst impact. 
Site staff will train study participants on the use of the ePRO diary at the Screening Visit, 
following which the device will be dispensed to the study participant for home use until the 
Week 16 Visit. The ePRO diary will be completed on a daily basis from Screening to the 
Week 16 Visit. 
The ePRO diary software will be programmed such that the study participants 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 
Good Clinical Practice (GCP) procedures (including study participant/site training and testing) 
will be performed at the study sites. 
8.2 
Safety assessments 
Planned timepoints for all safety assessments are provided in the SoA (Table 1-1). 
8.2.1 
Physical examination 
A physical examination will be performed at the visits specified in the SoA (Table 1-1). 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 (Section 8.2.7.3). Findings considered clinically significant 
changes since the physical examination at the Screening Visit will be recorded as AEs. 
Investigators should pay special attention to clinical signs related to previous serious illnesses. 
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8.2.2 
Vital signs 
Vital signs will be collected at every visit and will include systolic and diastolic blood pressure 
(BP), pulse rate, and body temperature (oral, axillary, or otic). Study participants should be 
sitting for 5 minutes before and during vital signs assessments. 
Vital signs should be assessed prior to IMP administration and prior to any blood collection. 
8.2.3 
12-lead ECGs 
Twelve-lead standard ECGs will be recorded at the Screening and Week 16 visits and read by a 
central ECG reader. Full details of ECG recording will be provided in the ECG Manual. 
8.2.4 
PHQ-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 a 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. 
Refer to Section 7.1 for PHQ-9-related IMP discontinuation criteria. 
8.2.5 
Clinical safety laboratory assessments 
All protocol-required laboratory assessments, as defined in Section 10.2 , must be conducted in 
accordance with the laboratory manual and the SoA (Table 1-1 ). See Section 10.2 and the SoA 
for the list, timing, and frequency of clinical laboratory tests to be performed. 
The Investigator must review the laboratory report, document this review, and record any 
clinically significant changes occurring during the study in the AE section of the eCRF. The 
laboratory reports must be filed with the source documents. Clinically significant abnormal 
laboratory findings are those which are not associated with the underlying disease, unless judged 
by the Investigator to be more severe than expected for the study participant's condition. 
All laboratory tests with values considered clinically significantly abnormal during participation 
in the study or within 20 weeks after the last dose of IMP should be repeated until the values 
return to normal or Baseline or are no longer considered clinically significant by the Investigator 
or Medical Monitor. If such values do not return to normal/Baseline within a period of time 
judged reasonable by the Investigator, the etiology should be identified and the Sponsor notified. 
If laboratory values from nonprotocol specified laboratory assessments performed at the 
institution’s local laboratory require a change in study participant management or are considered 
clinically significant by the Investigator (eg, SAE or AE or dose modification), then the results 
must be recorded in the eCRF. 
8.2.6 
Neuropsychiatric AE monitoring/suicidal risk monitoring 
Suicidal ideation and behavior will be assessed by using the C-SSRS. The questionnaire will be 
administered 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 C-SSRS 
assessments will be performed are specified in the SoA (Table 1-1). 
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The C-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). 
Participants respond to standardized clinical questions that are presented in a uniform fashion. 
The C-SSRS defines 5 subtypes of suicidal ideation and behavior in addition to self-injurious 
behavior with no suicidal intent. The C-SSRS takes approximately 3 to 10 minutes to complete. 
Refer to Section 7.1 for C-SSRS-related IMP discontinuation. 
8.2.7 
Assessment and management of TB and TB risk factors 
All study participants will be assessed for TB through physical examination for signs and 
symptoms of TB (Section 8.2.7.3.1), laboratory testing (Section 8.2.5), chest x-ray 
(Section 8.2.7.3.2), and TB questionnaire (Section 8.2.7.3.3). 
8.2.7.1 
Definitions 
Study participants with known active TB disease, at high risk of acquiring TB infection, or with 
untreated LTBI (ie, pending anti-TB prophylactic course) or current or history of NTMB 
infection are excluded from the study. 
a. Known TB infection whether present or past is defined as: 
• Active TB disease or clinical signs and symptoms strongly suggestive of TB (pulmonary 
or extra pulmonary) 
• History of active TB disease involving any organ system or findings in other organ 
systems consistent with TB, 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 disease that is not reported in the study participant's medical history 
b. High risk of acquiring TB infection is defined as: 
• Known close exposure (eg, sleeping in the same room) to another person with active TB 
infection within 3 months prior to Screening 
• Time spent within 3 months prior to Screening in a health care delivery setting or 
institution where individuals infected with TB are housed or where the risk of 
transmission of infection is high 
c. Latent TB infection is defined as an infection by Mycobacterium tuberculosis with: 
• A positive IGRA (or 2 indeterminate IGRAs), AND 
• Chest imaging (or other imaging) negative for TB infection, AND 
• Absence of signs, symptoms (eg, evidence of organ-specific involvement), or physical 
findings suggestive of TB infection. 
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d. Pulmonary NTMB infection is defined as a group of lung or extrapulmonary infections 
caused by mycobacteria different from M. tuberculosis infections. 
8.2.7.2 
Assessments at Screening 
At Screening, all study participants will have an IGRA test (QuantiFERON Gold Plus TB test is 
recommended), a chest x-ray (unless already performed within 3 months of Screening, a 
computed axial tomography [CAT] scan of the chest at Screening or within 3 months prior to 
Screening is acceptable, if available), and examination for signs and symptoms of TB. In 
addition, each study participant will complete a TB questionnaire directed at potential exposure 
to TB and symptoms of TB. 
Study participants diagnosed with active TB during Screening will be excluded from the study. 
Study participants with LTBI diagnosed during Screening must complete a full course of 
prophylaxis and can be rescreened after completion of 4 weeks of prophylaxis prior to Baseline. 
Study participant eligibility, retesting requirements, and treatment requirements at Screening are 
shown in Figure 8-1. 
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Figure 8-1: Decision tree for IGRA TB results at Screening 
 
IGRA=interferon-gamma release assay; LTBI=latent tuberculosis infection; TB=tuberculosis 
a IGRA retest must be done during the protocol-defined Screening window. 
b Study participants with LTBI diagnosed during Screening must complete a course of prophylaxis. Study 
participants can be rescreened after completion of 4 weeks of prophylaxis  prior to Baseline. 
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8.2.7.3 
Assessment and reporting of TB and TB risk factors during the study 
8.2.7.3.1 
Physical examination 
The Investigator should consider all potential sites of infection when assessing for TB during the 
physical examination, and other evaluations, and based on the study participant’s medical or 
social history. 
The most common primary focus of TB is the lung. Other sites may include gastrointestinal 
system, bone/joints, lymph glands, and meninges, etc. However, in immune-compromised 
patients, study participants, and/or patients treated with biologics, especially TNF inhibitors, 
extra pulmonary manifestations of TB are common compared to the normal population. 
Some common symptoms that the study participant may present are dependent on the primary 
focus of infection and may include cough, blood in sputum, night sweats, lymphadenitis, joint 
pain/swelling, spinal deformity, headache/confusion, abdominal pain (mimicking IBD), etc. 
Unusual presentations should always be considered. 
8.2.7.3.2 
Chest x-ray for TB 
Chest radiographic imaging is performed at Screening and results must be available at Baseline 
before first IMP administration unless a chest x-ray or CAT scan is available within 3 months 
prior to Screening. 
Additional chest x-rays or other imaging tests should be performed when positive signs and 
symptoms indicate pulmonary infection, including potential TB infection, or when close 
exposure to persons with TB is documented. 
8.2.7.3.3 
TB 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 the SoA (Table 1-1). The 
questionnaire will assist with the identification of study participants who may require therapy for 
TB. A study participant who answers “Yes” to the question “Has the study participant 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 the study 
participant has LTB or active TB (see Section 8.2.7.1). A “Yes” response to any of the questions 
during the study should trigger further assessments to determine if the study participant has 
either LTB or active TB infection. 
8.2.7.3.4 
IGRA test conversion 
The IGRA is a whole blood testing methodology for diagnosing M. tuberculosis infection. It has 
become the gold standard, but does not help in differentiating LTBI from active TB disease. 
Tuberculosis test conversion is defined as a positive or indeterminate (and confirmed 
indeterminate on repeat) IGRA result for the current test when previous IGRA test results were 
negative. All study participants with positive or indeterminate IGRA test results must 
immediately stop IMP administration. In case of an IGRA test conversion, the study participant 
must be considered as having either a suspected new latent or an active TB infection and be 
promptly referred to an appropriate specialist (eg, pulmonologist, infectious disease specialist) 
for further evaluation. However, the IGRA test conversion will not be detected since the IGRA 
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will be done at the Screening Visit only in this study. Additional assessments (eg, blood tests or 
IGRA, chest X-rays, or other imaging) should be performed where medically relevant and 
documented. Such conversions should be reported as AEs as described in the protocol. The AE 
term should be updated with the final diagnosis once available. 
8.2.7.3.5 
Latent TB 
In case the evaluation by the appropriate specialist diagnoses a new LTBI, a TB prophylactic 
therapy in accordance with applicable clinical guidelines should be immediately initiated. 
Study participants who initiate treatment for LTBI during the Screening Period must repeat 
initial screening laboratory parameters, all physical examinations, and questionnaires prior to 
randomization in the study, and must continue the full course of TB prophylactic therapy. Study 
participants can be rescreened after completion of 4 weeks of prophylaxis prior to Baseline 
If no TB prophylactic therapy is initiated for the newly diagnosed LTBI during Screening, the 
study participant must not be enrolled into the study. Every related action should be discussed in 
advance with the Medical Monitor. 
Any study participant who develops LTBI during the study must discontinue further 
administration of IMP and a PEOT Visit must be scheduled as soon as possible, but not later than 
the next regular visit. The study participant must be permanently withdrawn if the study 
participant is diagnosed with 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. Once withdrawn, the PEOT Visit must be scheduled 
as soon as possible, and the study participant should be encouraged to keep the SFU Visit. Latent 
TB infection must be reported as an AE. Follow-up reports should be completed as per protocol 
requirement until such time as the LTBI resolves. 
8.2.7.3.6 
Active TB or nontuberculosis mycobacterium infection 
Study participants who develop active TB or NTMB infection during the study must be 
withdrawn from the study. The study participant must be immediately permanently discontinued 
from IMP and a PEOT Visit must be scheduled as soon as possible, but no later than the next 
scheduled visit. The study participant should be encouraged to keep the SFU Visit as specified 
by the protocol. Treatment for active TB or NTMB should be started immediately. 
Confirmed active TB is always considered an SAE. UCB’s process requires that these must be 
captured on an SAE Report Form and provided to the Sponsor in accordance with SAE reporting 
requirements (Section 10.3 [Appendix 3]). Follow-up reports should be completed as per 
protocol requirement until such time as the TB infection resolves. 
8.2.7.3.7 
Tuberculosis management of LTBI, active TB, or other NTMB 
infection identified during study 
During the study, study participants who develop evidence of LTBI, active TB, or NTMB 
infection must immediately stop further administration of IMP and will be referred to a TB 
specialist (pulmonologist or infectious disease specialist) for further evaluation. Study 
participants diagnosed with active TB or LTBI should receive appropriate TB or prophylaxis 
therapy. The study participant should be transferred to the care of his/her physician and managed 
according to the standard of care. 
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Study participants identified as having 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 assessments. The study participant should be encouraged to 
complete a SFU Visit 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 and compliant TB treatment shall be followed. 
Additional details on TB detection and management are provided in the UCB TB Detection 
Procedure Guideline. 
8.2.8 
Adverse events and SAEs 
Adverse events will be reported by the study participant. 
The Investigator and any designees are responsible for detecting, documenting, and recording 
events that meet the definition of an AE or SAE and remain responsible for following up AEs 
that are serious, considered related to the study treatment or study procedures, or that caused the 
study participant to discontinue the IMP or the study (Section 7). 
8.2.8.1 
Time period and frequency for collecting AE and SAE information 
All AEs and SAEs will be collected from the signing of the ICF until the SFU Visit at the time 
points specified in the SoA (Table 1-1). 
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 post-treatment periods required by the 
protocol, must be reported in the CRF even if no IMP was taken but specific study procedures 
were conducted. This includes all AEs not present prior to the Screening Visit and all AEs that 
recurred or worsened after the Screening visit. 
All SAEs will be recorded and reported to the Sponsor or designee within 24 hours, as indicated 
in Section 10.3. The Investigator will submit any updated SAE data to the Sponsor within 
24 hours of it being available. 
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 
20 weeks from the final dose of IMP for each study participant, and to also inform study 
participants 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. 
The method of recording, evaluating, and assessing causality of AEs, SAEs and the procedures 
for completing and transmitting SAE reports are provided in Section 10.3. 
8.2.8.2 
Method of detecting AEs and SAEs 
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
nonleading verbal questioning of the study participant is the preferred method to inquire about 
AE occurrences. 
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8.2.8.3 
Follow-up of AEs and SAEs 
After the initial AE/SAE report, the Investigator is required to proactively follow each 
participant at subsequent visits/contacts. All will be followed until resolution, stabilization, the 
Investigator determines that it is no longer clinically significant, the event is otherwise explained, 
or the participant is lost to follow up (as defined in Section 7.3). Further information on 
follow-up procedures is given in Appendix 3 (Section 10.3). 
8.2.8.4 
Regulatory reporting requirements for SAEs 
Prompt notification by the Investigator to the Sponsor of a SAE is essential so that legal 
obligations and ethical responsibilities towards the safety of study participants and the safety of a 
IMP under clinical investigation are met. 
The Sponsor has a legal responsibility to notify both the local regulatory authority and other 
regulatory agencies about the safety of IMP under clinical investigation. The Sponsor will 
comply with Korean regulatory requirements relating to safety reporting to the regulatory 
authority, IRB/IEC, and Investigators. 
Investigator safety reports must be prepared for suspected unexpected serious adverse reactions 
(SUSAR) according to local regulatory requirements and Sponsor policy, and forwarded to 
Investigators as necessary. 
An Investigator who receives an Investigator safety report describing a SAE or other specific 
safety information (eg, summary or listing of SAEs) from the Sponsor will review and then file it 
along with the IB, and will notify the IRB/IEC, if appropriate according to local requirements. 
8.2.8.5 
Pregnancy 
Details of all pregnancies in female study participants and female partners of male study 
participants will be collected after the start of study treatment and until the SFU Visit. 
If a pregnancy is reported, the Investigator must immediately inform the Sponsor within 24 hours 
of learning of the pregnancy and should follow the procedures outlined in Appendix 4 
(Section 10.4). 
The female study participant should be discontinued from the IMP as soon as pregnancy is 
known (by positive pregnancy test), and the following should be completed: 
• The study participant should return for a PEOT Visit. 
• The study participant should immediately stop the intake of the IMP. 
• A SFU Visit should be scheduled 20 weeks after the study participant has discontinued IMP. 
Abnormal pregnancy outcomes (eg, spontaneous abortion, fetal death, stillbirth, congenital 
anomalies, ectopic pregnancy) are considered SAEs. 
8.2.8.6 
AEs of special interest 
An adverse event 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.For bimekizumab, the following 
events require immediate reporting (within 24 hours regardless of seriousness) to UCB: 
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• Hy’s Law 
− Potential Hy’s Law, defined as ALT or AST ≥3×ULN with coexisting total bilirubin 
≥2×ULN in the absence of ALP ≥2×ULN, with no alternative explanation for the 
biochemical abnormality (ie, without waiting for any additional etiologic investigations 
to have been concluded). Follow-up information should be reported if an alternative 
etiology is identified during investigation and monitoring of the study participant. 
8.2.8.7 
Other safety topics of interest 
Prespecified safety topics of interest for the study are: infections (serious, opportunistic, fungal, 
and TB), neutropenia, hypersensitivity, injection site reactions, neuropsychiatric AEs (including 
SIB-related AEs), depression, major CV events, LFT changes/enzyme elevations, malignancies, 
and IBD. 
These are based on findings from the bimekizumab 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. 
The reporting requirements for events relating to TB are as follows: 
• The IGRA test conversions defined as a positive or indeterminate (and confirmed 
indeterminate on repeat) should be reported as AEs. The AE term would need to be updated 
with final diagnosis once available. 
• Latent TB infection must be reported as an AE. Follow-up reports should be completed as 
per protocol requirement until the LTBI resolves. 
• Confirmed active TB is always considered an SAE and must be reported per SAE reporting 
instructions in the study protocol. Follow-up reports should be completed as per protocol 
requirement until the TB infection resolves. 
8.2.8.8 
Anticipated SAEs 
The following Anticipated SAEs are anticipated to occur in the population studied in this 
protocol at some frequency that is independent of drug exposure (Table 8-4). 
This list does not change the Investigator’s obligation to report all SAEs (including Anticipated 
SAEs) as detailed in Section 10.3. 
 Table 8-4: Anticipated SAEs for study participants with moderate to severe 
plaque PSO 
MedDRA system organ 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 participant. 
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8.3 
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, study participants, regulatory 
authorities, and IRBs/IECs will be informed appropriately and as early as possible. 
The Study Physician or medically qualified designee/equivalent will conduct an ongoing review 
of SAEs and perform ongoing SAE reconciliations in collaboration with the Patient Safety (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 results) for which data will be periodically reviewed during the course of the 
study. 
8.4 
Treatment of overdose 
For this study, any dose of bimekizumab greater than that prescribed in the protocol will be 
considered an overdose. Overdose events are only considered AEs or SAEs if there are 
associated clinical signs and symptoms or if the act of taking the excess IMP itself is an AE or 
SAE (eg, suicide attempt). 
UCB does not recommend specific treatment for an overdose. Any signs or symptoms of adverse 
reactions should be treated symptomatically as per standard care by the Investigator. 
In the event of an overdose, the Investigator should: 
1. Contact the Medical Monitor immediately 
2. Closely monitor the study participant for any AE/SAE and laboratory abnormalities until 
bimekizumab can no longer be detected systemically (at least 90 days) 
3. Obtain a plasma sample for PK analysis as soon as possible after the final dose of IMP if 
requested by the Medical Monitor (determined on a case-by-case basis) 
4. Document the quantity of the excess dose as well as the duration of the overdose in the eCRF 
8.5 
Pharmacokinetics 
Blood samples will be collected prior to dosing for measurement of plasma concentrations of 
bimekizumab at all timepoints described in Table 1-1. 
Instructions for the collection and handling of biological samples will be provided by the 
Sponsor. The actual date and time (24-hour clock time) of each sample will be recorded. 
Samples will be used to evaluate the PK of bimekizumab. Samples collected for analyses of 
bimekizumab plasma concentration may also be used to evaluate safety or efficacy aspects 
related to concerns arising during or after the study. 
Study participant confidentiality will be maintained. At visits during which blood samples for the 
determination of plasma concentrations of bimekizumab will be taken, 1 sample of sufficient 
volume can be used. 
Drug concentration information that may unblind the study will not be reported to any blinded 
study personnel as long as the study remains blinded. 
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8.6 
Genetics 
Genetics are not evaluated in this study. 
8.7 
Pharmacodynamics 
Pharmacodynamic parameters are not evaluated in this study. 
8.8 
Biomarkers 
Biomarkers are not evaluated in this study. 
8.9 
Immunogenicity assessments 
Antibodies to bimekizumab will be evaluated in plasma samples collected from all study 
participants according to the SoA (Table 1-1). Additionally, plasma samples should also be 
collected at the final visit from study participants who discontinued IMP or withdrew from the 
study. These samples will be tested by the Sponsor or Sponsor's designee. 
A tier-based approach will be used, consisting of consecutive screening, confirmatory and 
titration methods. Plasma samples will be screened for antibodies binding to bimekizumab and 
the titer of confirmed positive samples will be reported. Other analyses may be performed to 
verify the stability of antibodies to bimekizumab and/or further characterize the immunogenicity 
of bimekizumab. 
The detection and characterization of antibodies to bimekizumab will be performed using 
validated assay methods by or under the supervision of the Sponsor. The procedures for sample 
analysis and the relevant validation results will be described in a separate bioanalytical report. 
All samples collected for detection of antibodies to IMP will also be evaluated for bimekizumab 
plasma concentration to enable interpretation of the antibody data. Confirmed positive antibody 
samples will be further characterized for their ability to neutralize the activity of 
bimekizumab. Samples may be stored for a maximum of 20 years (or according to local 
regulations) following the LPLV for the study at a facility selected by the Sponsor, to enable 
further analysis of immune responses to bimekizumab. 
8.10 
Health economics or medical resource utilization and health 
economics 
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study. 
9 
STATISTICAL CONSIDERATIONS 
A description of statistical methods is provided below and will be described in more detail in the 
Statistical Analysis Plan (SAP). 
9.1 
Definition of analysis sets 
The Enrolled Set (ES) will consist of all study participants who have given informed consent. 
The Randomized Set (RS) will consist of all randomized study participants. 
The Safety Set (SS) will consist of all study participants that received at least 1 dose of the IMP. 
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The Full Analysis Set (FAS) will consist of all randomized study participants that received at 
least 1 dose of the IMP and have a valid measurement of the co-primary efficacy variables at 
Baseline. 
The Per-Protocol Set (PPS) will consist of all study participants in the RS who had no important 
protocol deviations affecting the co-primary efficacy variables. Important protocol deviations 
will be predefined, and study participants with important protocol deviations will be evaluated 
during ongoing data cleaning meetings prior to unblinding the data (see Section 9.5). 
The Pharmacokinetics Per-Protocol Set (PK-PPS) will consist of all randomized study 
participants 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. 
9.2 
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, standard deviation, median, minimum, and maximum, unless stated otherwise. 
All analyses will be performed using SAS® version 9.3 or later (SAS Institute, Cary, NC, US). 
The statistical analysis of the co-primary efficacy variables will be performed using a Type I 
error rate at a 2-sided alpha level of 0.05. 
9.3 
Planned efficacy/outcome analyses 
Efficacy variables will be analyzed for all study participants in the RS. 
9.3.1 
Efficacy estimands 
The following 4 attributes describe the estimands (International Council for Harmonisation 
[ICH] Addendum, 2019) that will be used to define the treatment effect of interest for the 
co-primary endpoints of study participant-level outcomes: 
PASI90 response at Week 16: 
1. Treatment: 320mg bimekizumab Q4W for 16 weeks. 
2. Target Population: adult Korean study participants meeting the protocol-specified 
inclusion/exclusion criteria. 
3. Intercurrent event handling: An intercurrent event is defined as discontinuation of IMP prior 
to Week 16. A composite strategy will be implemented in which a positive clinical outcome 
is defined as achieving PASI90 response at Week 16 and not discontinuing IMP through 
Week 16. 
4. Study participant-level summary measure: Odds ratio comparing bimekizumab to placebo. 
Any missing data not associated with discontinuation of IMP will also be imputed as a 
nonresponse. 
IGA 0/1 (clear or almost clear with at least a 2-category improvement from Baseline) response at 
Week 16: 
1. Treatment: 320mg bimekizumab Q4W for 16 weeks. 
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2. Target Population: adult Korean study participants meeting the protocol-specified 
inclusion/exclusion criteria. 
3. Intercurrent event handling: An intercurrent event is defined as discontinuation of IMP prior 
to Week 16. A composite strategy will be implemented in which a positive clinical outcome 
is defined as achieving IGA 0/1 response at Week 16 and not discontinuing IMP through 
Week 16. 
4. Study participant-level summary measure: Odds ratio comparing bimekizumab to placebo. 
Any missing data not associated with discontinuation of IMP will also be imputed as a 
nonresponse. 
The secondary efficacy binary endpoints (PASI100 response at Week 16, IGA 0 response at 
Week 16, PASI75 response at Week 4, PSD [P-SIM] [itch, pain, and scaling] response at 
Week 16, Scalp IGA 0/1 response at Week 16, and DLQI Total Score 0/1 response at Week 16) 
will have the same estimand structure as for the primary estimands. 
The following 4 attributes describe the estimand (ICH Addendum, 2019) that will be used to 
define the treatment effect of interest for the secondary efficacy endpoint percentage change 
from Baseline in BSA affected by PSO Week 16: 
1. Target population: Study participants meeting the protocol-defined inclusion/exclusion 
criteria. 
2. Study participant-level outcome: Percentage change from Baseline in BSA affected by PSO 
at Week 16 
3. Intercurrent event handling: A hypothetical strategy will be implemented in which the 
estimand targets the treatment difference in a scenario where an intercurrent event does not 
occur, such that outcomes for study participants without an intercurrent event are as 
observed, and outcomes for study participants with an intercurrent event are treated as though 
they had completed the randomized study treatment through Week 16 by imputing data 
following an intercurrent event using multiple imputation (MI). 
4. Study participant-level summary measure: Difference in the adjusted means between 
bimekizumab and placebo. 
Any missing data not associated with discontinuation of IMP will also be imputed using MI. 
9.3.2 
Analysis of the primary efficacy/primary endpoint 
The co-primary efficacy variables for this study will be PASI90 response and IGA 0/1 response 
at Week 16.  
The primary analyses for these endpoints will be produced on the RS. In addition, sensitivity 
analyses for the co-primary endpoints will be produced on the FAS and PPS. Observed case 
summaries (excluding subjects with missing PASI/IGA data at Week 16) will also be provided. 
Estimands related to primary efficacy analyses are described in Section 9.3.1. 
An intercurrent event is defined as discontinuation of IMP prior to Week 16. A composite 
strategy will be implemented in which a positive clinical outcome is defined as achieving the 
primary endpoint (PASI90 or IGA 0/1) at Week 16 and not discontinuing IMP prior to Week 16. 
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The justification of this approach is that discontinuation of IMP for any reason is considered to 
be indicative of an ineffective response to the IMP. Therefore, a successful primary outcome 
depends both on achieving the response (PASI90 or IGA 0/1) and continuing study treatment 
through 16 weeks. 
A study participant will be classified as a PASI90 responder if the PASI score at Week 16 has 
improved at least 90% from Baseline and the study participant has not discontinued IMP prior to 
Week 16. 
A study participant will be classified as a IGA 0/1 responder if the IGA score at Week 16 is 0 or 
1 (clear or almost clear) with at least a 2-category improvement from Baseline in the IGA score 
and the study participant has not discontinued IMP prior to Week 16. 
The evaluation of superiority (bimekizumab vs placebo treatment comparison) will be based on 
the Cochran-Mantel-Haenszel (CMH) test. Odds ratios and 95% confidence intervals (CIs) based 
on the CMH method will also be presented. 
9.3.3 
Secondary efficacy endpoint analyses 
The secondary efficacy variables will be analyzed for all study participants in the RS. 
No formal statistical testing will be conducted for the secondary efficacy variables. Nominal 
p-values for the bimekizumab vs placebo treatment comparison will be described in the SAP. 
The secondary efficacy endpoints will be derived as follows: 
• PASI100 responder at Week 16: PASI score at Week 16 has improved by 100% from 
Baseline and the study participant has not discontinued IMP prior to Week 16. 
• IGA 0 responder at Week 16: IGA score at Week 16 is 0 (Clear) with at least a 2-category 
improvement from Baseline in the IGA score and the study participant has not discontinued 
IMP prior to Week 16. 
• PASI75 responder at Week 4: PASI score at Week 4 has improved by ≥75% from Baseline 
and the study participant has not discontinued IMP prior to Week 4. 
• PSD (P-SIM) itch responder at Week 16: Itch score has improved (decreased) by ≥4 points 
from Baseline to Week 16 (using weekly averages) and the study participant has not 
discontinued IMP prior to Week 16. This will be assessed only in study participants with a 
Baseline itch score ≥4. 
• PSD (P-SIM) pain responder at Week 16: Pain score has improved (decreased) by ≥4 points 
from Baseline to Week 16 (using weekly averages) and the study participant has not 
discontinued IMP prior to Week 16. This will be assessed only in study participants with a 
Baseline pain score ≥4. 
• PSD (P-SIM) scaling responder at Week 16: Scaling score has improved (decreased) by 
≥4 points from Baseline to Week 16 (using weekly averages) and the study participant has 
not discontinued IMP prior to Week 16. This will be assessed only in study participants with 
a Baseline scaling score ≥4. 
• Scalp IGA 0/1 responder at Week 16 for study participants with scalp involvement at 
Baseline: Scalp IGA score at Week 16 is 0/1 (clear or almost clear) with at least a 2-category 
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improvement from Baseline in the IGA score and the study participant has not discontinued 
IMP prior to Week 16. Only study participants with a Scalp IGA score ≥2 at Baseline will be 
included. 
• DLQI Total Score 0/1 at Week 16: DLQI Total score is equal to 0 or 1 at Week 16 and the 
study participant has not discontinued IMP prior to Week 16. 
For the binary secondary efficacy endpoints assessing the superiority of bimekizumab vs 
placebo, the estimand structure as specified for the primary analysis will be implemented. 
For the continuous change from Baseline efficacy endpoint, percent change from Baseline in 
BSA affected by PSO at Week 16, an analysis of covariance (ANCOVA) model will be used 
with fixed effects of treatment and Baseline value as a covariate. Missing data will be imputed 
via MI as outlined in the estimand structure (Section 9.3.1). If there are model convergence 
issues with MI, a last observation carried forward (LOCF) approach will be used. 
For all secondary efficacy endpoints, observed data summaries will also be presented. 
9.3.4 
Tertiary efficacy endpoint analyses 
The tertiary efficacy variables will be analyzed for all study participants in the RS. 
Binary (responder) variables will be summarized using frequency tables by treatment group for 
each visit; nonresponder imputation (NRI) and observed case results will be displayed. 
Continuous variables will be summarized using descriptive statistics by treatment group for each 
visit. No imputation will be applied to continuous variables, only observed data will be 
summarized. 
Time to PASI50, PASI75, PASI90, and PASI100 response will be estimated using the Kaplan-
Meier product-limit method for each treatment group. 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. 
Study participants who discontinue IMP prior to achieving a response will be censored at the 
date of the last observed PASI assessment on or prior to the date of IMP discontinuation. Study 
participants who complete the study without achieving the given response will be censored at the 
date of the last observed PASI assessment. 
Study participants will be censored at Baseline (Day 0) if there is no Baseline PASI assessment 
or no post-Baseline PASI assessment. 
The median time to response, including the 2-sided 95% CI, will be calculated for each treatment 
group. 
9.4 
Planned safety and other analyses 
Safety variables will be analyzed for all study participants in the SS.  
9.4.1 
Safety analyses 
9.4.1.1 
AEs 
Adverse events will be coded according to the Medical Dictionary for Regulatory Activities 
(MedDRA v19.0). Treatment-emergent AEs are defined as those AEs that have a start date on or 
following the first dose of IMP. 
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The frequency of all TEAEs will be presented for each treatment group separately by system 
organ class, high level term, and preferred term. The data will be displayed as number of study 
participants experiencing the TEAE, percentage of study participants, and number of TEAEs. 
Additional tables will summarize serious TEAEs, TEAEs leading to discontinuation, TEAEs by 
severity, and TEAEs categorized as safety topics of interest and AESIs. Definitions for 
categorizing TEAEs as safety topics of interest and AESIs will be provided in the SAP. 
Further details of TEAE summaries will be provided in the SAP. 
9.4.1.2 
Vital signs 
Vital signs will be summarized by visit. Absolute values and change from Baseline in systolic 
and diastolic BP and pulse rate will be presented descriptively by visit for each treatment group. 
Markedly abnormal vital signs will be summarized. Definitions of markedly abnormal vital signs 
will be given in the SAP. 
9.4.1.3 
Hematology/biochemistry 
Treatment-emergent markedly abnormal (TEMA) laboratory values are defined as those that 
have an assessment date on or following first dose of IMP. 
Laboratory assessments will be analyzed by visit. Absolute values and change from Baseline in 
each laboratory parameter will be presented descriptively for each treatment group. The 
incidence rate of TEMA laboratory values at the parameter level will also be presented 
descriptively for each treatment group. Definitions for markedly abnormal laboratory values will 
be provided in the SAP. 
9.4.1.4 
Physical examination 
Clinically significant changes from Baseline in physical examination findings will be reported as 
AEs and included in the TEAE summarization described in Section 9.4.1.1. 
9.4.1.5 
ECG 
Changes from Baseline in ECG parameters will be summarized by treatment group. ECG outliers 
will be summarized as defined in the SAP. 
9.4.1.6 
PHQ-9 
Change from Baseline in PHQ-9 score will be summarized over time by treatment group. The 
number of study participants with a PHQ-9 score ≥15 and ≥20 at any time will be summarized. 
9.4.1.7 
C-SSRS 
The incidence of study participants with suicidal ideation, suicidal behavior, suicidal ideation or 
behavior, and self-injurious behavior will be summarized by visit and treatment group. 
9.4.2 
Pharmacokinetics and antidrug antibody analyses 
Plasma bimekizumab concentrations will be summarized for the PK-PPS at each time point 
using descriptive statistics. In addition, PK model-based analyses may be performed and reported 
separately. 
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Antidrug antibody (ADAb) data will be evaluated for each study participant in the SS, and rates 
of ADAb-positive study participants will be calculated. Neutralizing antidrug antibody data will 
also be evaluated. Further details will be presented in the SAP. 
9.5 
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 study participant. The criteria for identifying important protocol deviations will be 
defined within the appropriate protocol-specific document at study start. Consistent with 
standard industry practice, the protocol deviation specification document may be refined during 
the study. 
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. 
Important protocol deviations may lead to exclusion from the PPS or PK-PPS, but will not lead 
to exclusion from the RS or FAS (see Section 9.1). 
In line with the studies that PS0032 will be bridged to, anticipated important protocol deviations 
will be categorized as follows:  
• Inclusion criteria deviation 
• Exclusion criteria deviation 
• Incorrect treatment or dose 
• Treatment noncompliance 
• Withdrawal criteria deviation 
• Procedural noncompliance 
• Prohibited concomitant medication use 
Deviations related to the Coronavirus Disease 2019 (COVID-19) global pandemic are 
unavoidable deviations from the protocol due to confirmed COVID-19 infection, suspected 
COVID-19 infection, general circumstances around COVID-19 without infection, or any other 
deviation from the protocol due to COVID-19. COVID-19 protocol deviations will be reviewed 
as part of the ongoing data cleaning process. 
Summaries of all important protocol deviations will be produced. Deviations due to COVID-19 
will also be summarized. 
9.6 
Handling of dropouts or missing data 
Pharmacokinetic analyses will be based on observed data; no imputation will be used. However, 
if plasma concentration measurements are below the level of quantification, then for calculation 
of the derived statistics the result will be set to half of the lower level of quantification. 
Study participants who prematurely discontinue IMP (intercurrent event) will have their data 
imputed under the estimand framework described in Section 9.3.1. 
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Missing data outside of an intercurrent event for the binary (responder) efficacy variables will be 
imputed; study participants with missing data will be considered as nonresponders for the 
respective time point. Missing data for the continuous secondary efficacy variable percentage 
change from Baseline in BSA affected by PSO will be imputed using MI. If the imputation 
model cannot converge, the LOCF method will be used. Further details will be provided in the 
SAP. 
9.7 
Planned interim analysis and data monitoring 
After all study participants complete the Week 16 visit, an interim analysis may be performed. A 
final analysis and final CSR will be prepared once all data (through the SFU visit for study 
participants not entering the MAP) have been collected. 
9.8 
Determination of sample size 
Sample size and power calculations are performed based on a total of 45 study participants being 
randomly assigned in a 2:1 ratio at Baseline to one of the following treatment groups: 
• Bimekizumab 320mg Q4W (30 study participants) 
• Placebo (15 study participants) 
The primary efficacy analysis is based on the comparison of bimekizumab to placebo for the 
co-primary efficacy endpoints of PASI90 and IGA 0/1 response at Week 16. The assumed 
responder rates for PASI90 at Week 16 are 70% and 13.3% for bimekizumab and placebo, 
respectively. Based on the number of study participants planned, this equates to 21 and 
2 responders in the bimekizumab and placebo treatment groups, respectively. In the global 
Phase 3 bimekizumab PSO program, the PASI90 responder rate ranged from 85% to 90%. The 
assumption here is relatively low to account for increased variability due to a small sample size 
and the possibility of missing data due to COVID-19. Additionally, the placebo PASI90 
responder rate assumption is higher than observed in the Phase 3 program to account for 
potential variability due to small sample size. These assumptions are conservative against a 
bimekizumab treatment effect. 
The power to show statistical superiority of bimekizumab relative to placebo at a 2-sided 
significance level of 0.05 under these assumptions is 95% for PASI90 at Week 16. As the 
Phase 3 studies demonstrated similar responder rates between PASI90 and IGA 0/1, this 
calculation is considered sufficient to justify the sample size. These calculations were performed 
using nQuery Advisor® 7.0 based on a two-group continuity corrected chi-square test of equal 
proportions (with unequal n). 
10 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS 
10.1 
Appendix 1: Regulatory, ethical, and study oversight 
considerations 
10.1.1 
Regulatory and ethical considerations 
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. 
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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 study 
participant-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 study participants or others, and any protocol 
deviations, to eliminate immediate hazards to study participants. 
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 study 
participants. 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 study participant 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. 
10.1.2 
Financial disclosure 
Insurance coverage will be handled according to local requirements. 
Finance and insurance are addressed in the Investigator and/or Contract Research Organization 
(CRO) agreements, as applicable. 
10.1.3 
Informed consent process 
Study participant’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 study participant in both oral and written form by the 
Investigator (or designee). Each study participant will have the opportunity to discuss the study 
and its alternatives with the Investigator. 
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Prior to participation in the study, the ICF should be signed and personally dated by the study 
participant and by the person who conducted the informed consent discussion (Investigator or 
designee). The study participant must receive a copy of the signed and dated ICF. As part of the 
consent process, each study participant 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. 
The study participant may withdraw consent to participate in the study at any time. A study 
participant 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 study participant, 
without having obtained written consent to participate in the study. 
10.1.4 
Data protection 
UCB staff (or designee) will affirm and uphold the study participant’s confidentiality. 
Throughout this study, all data forwarded to UCB (or designee) will be identified only by the 
study participant 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 
study participant’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 admissions occurring during a study participant’s study participation, and autopsy 
reports for deaths occurring during the study). 
The study participant must be informed that personal study-related data will be used by the 
Sponsor in accordance with local data protection law. The level of disclosure must also be 
explained to the study participant. 
The study participant must be informed that his/her medical records may be examined by 
Clinical Quality Assurance auditors or other authorized personnel appointed by the Sponsor, by 
appropriate IRB/IEC members, and by inspectors from regulatory authorities. 
10.1.5 
Committee structure 
Cardiovascular, Gastrointestinal, and Neuropsychiatric Adjudication Committees will 
periodically review data from this study. Details will be provided in the Cardiovascular, 
Gastrointestinal, and Neuropsychiatric Adjudication Committee charters. 
Adjudication Committee members may not participate in the study as principal or 
co-Investigators, or as study participant care physicians, and must not be members of the study 
team at UCB or the conducting CRO. The duration of membership for the committees will be 
inclusive of planned analyses for this study.  
10.1.6 
Data quality assurance 
All study participant data relating to the study will be recorded in the eCRF unless transmitted to 
the Sponsor or designee electronically (eg, laboratory data). The Investigator is responsible for 
verifying that data entries are accurate and correct by physically or electronically signing the 
eCRF. 
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The Investigator must maintain accurate documentation (source data) that supports the 
information entered in the eCRF. 
The Investigator must permit study-related monitoring, audits, IRB/IEC review, and regulatory 
agency inspections and provide direct access to source data documents. 
The Sponsor or designee is responsible for the data management of this study including quality 
checking of the data. 
Study monitors will perform ongoing source data verification to confirm that data entered into 
the eCRF by authorized site personnel are accurate, contemporaneous, original, and attributable 
from source documents; that the safety and rights of study participants are being protected; and 
that the study is being conducted in accordance with the currently approved protocol and any 
other study agreements, ICH-GCP, and all applicable regulatory requirements. 
All essential documents must be retained by the Investigator for the minimum retention period 
mandatory under the applicable local laws and regulations. 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. 
10.1.6.1 
eCRF completion 
The Investigator is responsible for prompt reporting of accurate and complete 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. 
10.1.6.2 
Apps 
Each study participant will be provided with a mobile phone with a preinstalled application 
(app). The study-specific app will collect data from each participant throughout the study. The 
app will support the participant to complete study-specific activities, as follows: 
• Receiving reminders and notifications 
• Scheduling visits with the Investigator and/or authorized site representative(s) 
• Completing PSD daily diary 
The Investigator and authorized site representative(s) will have access to a secure website portal 
via unique access credentials to access the study data from the completed activities noted above. 
Data will be reviewed by the Investigator via the website portal view of participant-entered data 
results. 
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Furthermore, this app is designed to only record data associated with the participant’s disease 
state, and therefore it is neither designed nor intended to be used to collect or report 
safety-related information about the participant. 
10.1.7 
Source documents 
All source documents must be accurate, clear, unambiguous, permanent, and capable of being 
audited. They 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 printouts of eCRFs 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, QOL questionnaires, 
or video, for example. Source documents should be kept in a secure, limited access area. 
Electronic PRO measures and the TB questionnaire will be completed by each study participant 
and will be collected via electronic device. 
Source documents that are computer generated and stored electronically must be printed for 
review by the monitor. Once printed, these copies should be signed and dated by the Investigator 
and become a permanent part of the study participant’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 must be saved and stored as instructed by UCB (or designee). 
10.1.8 
Study and site closure 
The Sponsor designee reserves the right to close the study site or terminate the study at any time 
for any reason at the sole discretion of the Sponsor. Study sites will be closed upon study 
completion. A study site is considered closed when all required documents and study supplies 
have been collected and a study-site closure visit has been performed. 
The Investigator may initiate study-site closure at any time, provided there is reasonable cause 
and sufficient notice is given in advance of the intended termination. 
Reasons for the early closure of a study site by the Sponsor or Investigator may include, but are 
not limited to: 
• Failure of the Investigator to comply with the protocol, the requirements of the IRB/IEC or 
local health authorities, the Sponsor's procedures, or GCP guidelines 
• Inadequate recruitment of study participants by the Investigator 
• Discontinuation of further study bimekizumab development 
10.1.9 
Publication policy 
The results of this study may be published or presented at scientific meetings. If this is foreseen, 
the Investigator agrees to submit all manuscripts or abstracts to the Sponsor before submission. 
This allows the Sponsor to protect proprietary information and to provide comments. 
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The Sponsor will comply with the requirements for publication of study results. In accordance 
with standard editorial and ethical practice, the Sponsor will generally support publication of 
multicenter studies only in their entirety and not as individual site data. In this case, a 
coordinating Investigator will be designated by mutual agreement. 
Authorship will be determined by mutual agreement and in line with International Committee of 
Medical Journal Editors authorship requirements. 
10.1.10 
Clinical trial registration and results disclosure 
To comply with applicable laws, regulations and guidance, and provide information on the 
clinical study to the public in a timely manner, the sponsor will register this study on 
ClinicalTrials.gov or other publicly accessible websites on or before the start of the study, as 
defined by sponsor policies and applicable laws and/or regulations . 
The sponsor will post the results of the study on ClinicalTrials.gov and other publicly accessible 
websites and registries as required by sponsor policies and applicable laws and/or regulations. 
For results disclosure on public registries (eg, ClinicalTrials.gov), TEAEs and TE-SAEs will be 
published. 
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10.2 
Appendix 2: Clinical laboratory tests 
• The tests detailed in the table below will be performed by the central laboratory, with the 
exception of urine dipsticks and urine pregnancy tests, which will be performed locally at the 
site. 
• Local laboratory results are only required in the event that the central laboratory results are 
not available in time for either IMP administration and/or response evaluation. If a local 
sample is required, it is important that the sample for central analysis is obtained at the same 
time. Additionally, if the local laboratory results are used to make either an IMP decision or 
response evaluation, the results must be entered into the eCRF. 
• Protocol-specific requirements for inclusion or exclusion of study participants are detailed in 
Section 5.1 and Section 5.2 of the protocol. 
• Additional tests may be performed at any time during the study as determined necessary by 
the Investigator or required by local regulations. 
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Table 10-1: Protocol-required safety laboratory assessments 
Laboratory 
assessments 
Parameters 
Hematology 
Platelet count  
RBC indices: 
MCV 
MCH 
MCHC 
WBC count with differential: 
Neutrophils 
Lymphocytes 
Monocytes 
Eosinophils 
Basophils 
RBC count 
Hemoglobin 
Hematocrit 
Clinical 
chemistry1 
BUN 
Potassium 
AST 
Total bilirubin 
 
Creatinine 
Sodium 
ALT 
Glucose 
(nonfasting) 
 
Calcium 
Alkaline 
phosphatase 
Lipid panel 
Chloride 
 
GGT 
LDH  
Routine 
urinalysis 
• 
Specific gravity 
• 
pH, glucose, protein, blood, ketones, bilirubin, urobilinogen, nitrite, and 
leukocyte esterase by dipstick 
• 
Microscopic examination (if protein, blood, nitrite or leukocyte esterase is 
abnormal) 
Other Screening 
tests 
• 
Serum hCG pregnancy test (as needed for FOCBP) by central laboratory at 
Screening and urine pregnancy test locally for all assessments after Screening 
• 
IGRA testing 
• 
Urine drug screen 
• 
Serology (HIV antibody, HBsAg, and hepatitis C virus antibody) 
Specific details regarding the handling and processing of serum chemistry, 
hematology, and urinalysis samples are provided in the study laboratory manuals. 
ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea nitrogen; eCRF=electronic Case 
Report Form; HBsAg=hepatitis B surface antigen; hCG=human chorionic gonadotropin; GGT=gamma 
glutamyltransferase; HIV=human immunodeficiency virus; IGRA= interferon-gamma release assay; 
INR=international normalized ratio; LDH=lactate dehydrogenase; MCH=mean corpuscular hemoglobin; 
MCHC=mean corpuscular hemoglobin concentration; MCV=mean corpuscular volume; RBC=red blood cell 
count; ULN=upper limit of normal; WBC=white blood cell count 
a Details of liver chemistry stopping criteria and required actions and follow-up assessments after liver stopping or 
monitoring event are given in Section 7.1.1 and Appendix 6 (Section 10.6). All events of ALT 3×ULN and 
bilirubin 2×ULN (>35% direct bilirubin) or ALT 3×ULN and INR >1.5, if INR measured, may indicate severe 
liver injury (possible Hy’s Law) and must be reported as an SAE. 
Investigators must document their review of each laboratory safety report. 
 
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Laboratory/analyte results that could unblind the study will not be reported to investigative sites 
or other blinded personnel until the study has been unblinded. 
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10.3 
Appendix 3: AEs – definitions and procedures for recording, 
evaluating, follow up, and reporting 
Definition of AE 
AE definition 
• 
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally 
associated with the use of IMP, whether or not considered related to the IMP. 
• 
NOTE: An AE can therefore be any unfavorable and unintended sign (including an abnormal 
laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the 
use of IMP. 
 
Events meeting the AE definition 
• 
Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) or other 
safety assessments (eg, ECG, radiological scans, vital signs measurements), including those 
that worsen from Baseline, considered clinically significant in the medical and scientific 
judgment of the Investigator (ie, not related to progression of underlying disease). 
• 
Exacerbation of a chronic or intermittent preexisting condition including either an increase in 
frequency and/or intensity of the condition. 
• 
New conditions detected or diagnosed after IMP administration even though it may have been 
present before the start of the study. 
• 
Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction. 
• 
Signs, symptoms, or the clinical sequelae of a suspected overdose of either IMP or a 
concomitant medication. Overdose per se will not be reported as an AE/SAE unless it is an 
intentional overdose taken with possible suicidal/self-harming intent. Such overdoses should be 
reported regardless of sequelae. 
• 
"Lack of efficacy" or "failure of expected pharmacological action" per se will not be reported 
as an AE or SAE. Such instances will be captured in the efficacy assessments. However, the 
signs, symptoms, and/or clinical sequelae resulting from lack of efficacy will be reported as 
AE or SAE if they fulfill the definition of an AE or SAE. 
 
Events NOT meeting the AE definition 
• 
Any clinically significant abnormal laboratory findings or other abnormal safety assessments 
which are associated with the underlying disease, unless judged by the Investigator to be more 
severe than expected for the study participant’s condition. 
• 
The disease/disorder being studied or expected progression, signs, or symptoms of the 
disease/disorder being studied, unless more severe than expected for the study participant’s 
condition. 
• 
Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that leads to the 
procedure is the AE. 
• 
Situations in which an untoward medical occurrence did not occur (social and/or convenience 
admission to a hospital). 
• 
Anticipated day-to-day fluctuations of preexisting disease(s) or condition(s) present or detected 
at the start of the study that do not worsen. 
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Definition of SAE 
If an event is not an AE per definition above, then it cannot be an SAE even if serious conditions 
are met (eg, hospitalization for signs/symptoms of the disease under study, death due to 
progression of disease). 
A SAE is defined as any untoward medical occurrence that, at any dose: 
a. Results in death 
b. Is life-threatening 
The term ”life-threatening” in the definition of 'serious' refers to an event in which the study participant 
was at risk of death at the time of the event. It does not refer to an event, which hypothetically might 
have caused death, if it were more severe. 
c. Requires inpatient hospitalization or prolongation of existing hospitalization 
In general, hospitalization signifies that the study participant has been detained (usually involving at 
least an overnight stay) at the hospital or emergency ward for observation and/or treatment that would 
not have been appropriate in the physician’s office or outpatient setting. Complications that occur 
during hospitalization are AEs. If a complication prolongs hospitalization or fulfills any other serious 
criteria, the event is serious. When in doubt as to whether “hospitalization” occurred or was necessary, 
the AE should be considered serious. 
Hospitalization for elective treatment of a preexisting condition that did not worsen from Baseline is 
not considered an AE. 
d. Results in persistent disability/incapacity 
• 
The term disability means a substantial disruption of a person’s ability to conduct normal life 
functions. 
• 
This definition is not intended to include experiences of relatively minor medical significance 
such as uncomplicated headache, nausea, vomiting, diarrhea, influenza, and accidental trauma 
(eg, sprained ankle) which may interfere with or prevent everyday life functions but do not 
constitute a substantial disruption. 
e. Is a congenital anomaly/birth defect 
f. Important medical events: 
• 
Medical or scientific judgment should be exercised in deciding whether SAE reporting is 
appropriate in other situations such as, important medical events that may not be immediately 
life-threatening or result in death or hospitalization but may jeopardize the study participant or 
may require medical or surgical intervention to prevent one of the other outcomes listed in the 
above definition. These events should usually be considered serious. 
• 
Examples of such events include, but are not limited to, potential Hy’s law, invasive or 
malignant cancers, intensive treatment in an emergency room or at home for allergic 
bronchospasm, blood dyscrasias or convulsions that do not result in hospitalization, or 
development of drug dependency or drug abuse. 
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Recording and follow up of AE and/or SAE 
AE and SAE recording 
• 
When an AE/SAE occurs, it is the responsibility of the Investigator to review all 
documentation (eg, hospital progress notes, laboratory reports, and diagnostics reports) related 
to the event. 
• 
The Investigator will then record all relevant AE/SAE information in the eCRF. 
• 
It is not acceptable for the Investigator to send photocopies of the study participant’s medical 
records to UCB in lieu of completion of the AE/SAE eCRF page. 
• 
There may be instances when copies of medical records for certain cases are requested by 
UCB. In this case, all study participant identifiers, with the exception of the study participant 
number, will be redacted on the copies of the medical records before submission to UCB. 
• 
The Investigator will attempt to establish a diagnosis of the event based on signs, symptoms, 
and/or other clinical information. Whenever possible, the diagnosis (not the individual 
signs/symptoms) will be documented as the AE/SAE. 
Assessment of intensity 
The Investigator will make an assessment of intensity for each AE and SAE reported during the study 
and assign it to 1 of the following categories: 
• 
Mild: An event that is easily tolerated by the study participant, causing minimal discomfort and 
not interfering with everyday activities. 
• 
Moderate: An event that causes sufficient discomfort and interferes with normal everyday 
activities. 
• 
Severe: An event that prevents normal everyday activities. An AE that is assessed as severe 
should not be confused with a SAE. Severe is a category utilized for rating the intensity of an 
event; and both AEs and SAEs can be assessed as severe. 
• 
An event is defined as ‘serious’ when it meets at least 1 of the predefined outcomes as 
described in the definition of an SAE, NOT when it is rated as severe (eg, a severe AE may be 
either serious or not serious, depending on whether these criteria are also met). 
The National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) 
should be used as a supportive standardization instrument to evaluate AEs and SAEs, but the final 
intensity grading by the Investigator must be mild, moderate, or severe. 
 
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Assessment of causality 
• 
The Investigator is obligated to assess the relationship between IMP and each occurrence of 
each AE/SAE. 
• 
A "reasonable possibility" of a relationship conveys that there are facts, evidence, and/or 
arguments to suggest a causal relationship, rather than a relationship cannot be ruled out. 
• 
The Investigator will use clinical judgment to determine the relationship. 
• 
Alternative causes, such as underlying disease(s), concomitant therapy, and other risk factors, 
as well as the temporal relationship of the event to IMP administration will be considered and 
investigated. 
• 
The Investigator will also consult the IB and/or Product Information, for marketed products, in 
his/her assessment. 
• 
For each AE/SAE, the Investigator must document in the medical notes that he/she has 
reviewed the AE/SAE and has provided an assessment of causality. 
• 
There may be situations in which an SAE has occurred and the Investigator has minimal 
information to include in the initial report to UCB. However, it is very important that the 
Investigator always make an assessment of causality for every event before the initial 
transmission of the SAE data to UCB. 
• 
The Investigator may change his/her opinion of causality in light of follow-up information and 
send a SAE follow-up report with the updated causality assessment. 
• 
The causality assessment is one of the criteria used when determining regulatory reporting 
requirements. 
 
Follow up of AEs and SAEs 
• 
The Investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations as medically indicated or as requested by UCB to elucidate 
the nature and/or causality of the AE or SAE as fully as possible. This may include additional 
laboratory tests or investigations, histopathological examinations, or consultation with other 
health care professionals. 
• 
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 study participant is lost to follow up. 
This follow-up requirement applies to AEs, SAEs, and AEs of special interest. 
• 
If a study participant dies during participation in the study or during a recognized follow-up 
period, the Investigator will provide UCB with a copy of any postmortem findings including 
histopathology. 
• 
New or updated information will be recorded in the originally completed eCRF. 
• 
The Investigator will submit any updated SAE data to the UCB within 24 hours of receipt of 
the information. 
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Reporting of SAEs 
SAE reporting to UCB via an electronic data collection tool 
• 
The primary mechanism for reporting an SAE to UCB will be the electronic data collection 
tool. 
• 
If the electronic system is unavailable for more than 24 hours, then the site will use the paper 
SAE data collection tool (see next section). 
• 
The site will enter the SAE data into the electronic system as soon as it becomes available. 
• 
After the study is completed at a given site, the electronic data collection tool will be taken off-
line to prevent the entry of new data or changes to existing data. 
• 
If a site receives a report of a new SAE from a study participant or receives updated data on a 
previously reported SAE after the electronic data collection tool has been taken off-line, then 
the site can report this information on a paper SAE form (see next section) or to the UCB 
Study Physician by telephone. 
Contacts for SAE reporting can be found in SERIOUS ADVERSE EVENT REPORTING 
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10.4 
Appendix 4: Contraceptive guidance and collection of 
pregnancy information 
Definitions 
Female of childbearing potential (FOCBP) 
A woman is considered fertile following menarche and until becoming postmenopausal unless 
permanently sterile (see below). 
Women in the following categories are not considered FOCBP: 
1. Premenarchal 
2. Premenopausal female with 1 of the following: 
− Documented hysterectomy 
− Documented bilateral salpingectomy 
− Documented bilateral oophorectomy 
Note:  Documentation can come from the site personnel’s review of the study participant’s 
medical records, medical examination, or medical history interview. 
3. Postmenopausal female 
− A postmenopausal state is defined as no menses for 12 months without an alternative 
medical cause. A high follicle stimulating hormone (FSH) level in the postmenopausal 
range may be used to confirm a postmenopausal state in women not using hormonal 
contraception or hormonal replacement therapy (HRT). However, in the absence of 
12 months of amenorrhea, a single FSH measurement is insufficient. 
− Females on HRT and whose menopausal status is in doubt will be required to use one of 
the nonestrogen hormonal highly effective contraception methods if they wish to 
continue their HRT during the study. Otherwise, they must discontinue HRT to allow 
confirmation of postmenopausal status before study enrollment. 
Contraception guidance 
Female study participants 
FOCBPs are eligible to participate if they agree to use a highly effective method of contraception 
consistently and correctly as described in the table below. 
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Highly effective contraceptive methods a 
Highly effective contraceptive methods that are user dependent b 
Failure rate of <1% per year when used consistently and correctly.  
Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of 
ovulation c 
• 
Oral 
• 
Intravaginal 
• 
Transdermal 
Progestogen only hormonal contraception associated with inhibition of ovulation 
• 
Oral 
• 
Injectable 
Highly effective methods that are user independent c 
 
Implantable progestogen only hormonal contraception associated with inhibition of ovulation 
• 
Intrauterine device (IUD) 
• 
Intrauterine hormone-releasing system (IUS) 
• 
Bilateral tubal occlusion 
Vasectomized partner 
A vasectomized partner is a highly effective contraception method provided that the partner is the sole 
male sexual partner of the FOCBP and the absence of sperm has been confirmed. If not, an additional 
highly effective method of contraception should be used. 
Sexual abstinence 
Sexual abstinence is considered a highly effective method only if defined as refraining from heterosexual 
intercourse during the entire period of risk associated with the IMP. The reliability of sexual abstinence 
needs to be evaluated in relation to the duration of the study and the preferred and usual lifestyle of the 
study participant. 
a In case of newly started contraception pills/IUDs, Investigator should consider the correct timing of 
starting/applying such methods in relation to the menstrual cycle and the manufacturing instruction as when these 
newly started methods would become effective. 
b Typical use failure rates may differ from those when used consistently and correctly. Use should be consistent 
with local regulations regarding the use of contraceptive methods for study participants participating in clinical 
studies. 
c Hormonal contraception may be susceptible to interaction with the IMP, which may reduce the efficacy of the 
contraceptive method. In this case, two highly effective methods of contraception should be utilized during the 
treatment period and for at least 20 weeks after the final dose of IMP. 
• Woman of child bearing potential should only be included after a confirmed menstrual period 
and a negative highly sensitive serum pregnancy test. 
• Additional pregnancy testing should be performed as indicated in the SoA (Table 1-1) and as 
required locally. 
• Pregnancy testing will be performed whenever a menstrual cycle is missed or when 
pregnancy is otherwise suspected. 
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Male study participants with partners who become pregnant 
• The Investigator will attempt to collect pregnancy information on any male study 
participant’s female partner who becomes pregnant while the male study participant is in this 
study. This applies only to male study participants who receive IMP. If the study participant 
is later found to be on placebo, then pregnancy data collection can stop. 
• In cases where the partner of a male study participant enrolled in a clinical study becomes 
pregnant, the Investigator or designee is asked to contact the study participant 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/CRO contract monitor for 
the study. The Investigator will complete the information in the eCRF 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. 
• After obtaining the necessary signed Informed Consent from the pregnant female partner 
(and/or parent/legal representative), the Investigator will record pregnancy information on 
the appropriate form and submit it to the Sponsor within 1 working day of learning of the 
partner’s pregnancy. The female partner will also be followed to determine the outcome of 
the pregnancy. Information on the status of the mother and child will be forwarded to the 
Sponsor. Generally, the follow up will be 30 days after the delivery date. Any termination of 
the pregnancy will be reported regardless of fetal status (presence or absence of anomalies) 
or indication for the procedure. 
Female study participants who become pregnant 
• Any female study participant who becomes pregnant while participating in the study will 
discontinue IMP (see Section 8.2.8.5). 
• The Investigator will collect pregnancy information on any female study participant who 
becomes pregnant while participating in this study. Information will be recorded on the 
appropriate form and submitted to the Sponsor within 1 working day of learning of a study 
participant's pregnancy. The study participant will be followed to determine the outcome of 
the pregnancy. The Investigator will collect follow-up information on the study participant 
and the neonate and the information will be forwarded to the Sponsor. Generally, the follow 
up will be at least 30 days after the delivery date. Any termination of pregnancy will be 
reported, regardless of fetal status (presence or absence of anomalies) or indication for the 
procedure. 
• While pregnancy itself is not considered to be an AE or SAE, any pregnancy complication or 
elective termination of a pregnancy will be reported as an AE or SAE. A spontaneous 
abortion is always considered to be an SAE and will be reported as such. Any poststudy 
pregnancy-related SAE considered reasonably related to the IMP by the Investigator will be 
reported to the Sponsor as described in Section 8.2.8.5. While the Investigator is not 
obligated to actively seek this information in former study participants, he or she may learn 
of an SAE through spontaneous reporting. 
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10.5 
Appendix 5: Genetics 
Not applicable. 
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10.6 
Appendix 6: Liver safety – suggested actions and follow-up 
assessments 
The PDILI IMP discontinuation criteria for this study are provided in Section 7.1.1, 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 AE of special interest (see Section 8.2.8.6), and, if applicable, also reported as an 
SAE (see Section 8.2.8.4). 
Evaluation of PDILI consists of the diagnostic testing and continued monitoring included in 
Table 10-3 (specific tests dependent on laboratory results and corresponding symptoms) and 
consultation with a local hepatologist (if applicable; discussed in Section 10.6.1). 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 7.1.1.1). 
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 7.1.1), 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 10.6.2.1 are met, rechallenge with IMP may be appropriate. 
Table 10-2 summarizes the approach to investigate PDILI. 
 
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Table 10-2: Required investigations and follow up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or AST 
Total 
bilirubin 
Symptomsa of 
hepatitis or 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
≥3×ULN 
≥2×ULNb 
NA 
Hepatology consultc 
Medical Monitor 
must be notified 
within 24 hours 
(eg, by laboratory 
alert) and study 
participant discussed 
with Medical 
Monitor ASAP. 
Immediate IMP 
discontinuation.d 
Essential: Must have 
repeat liver chemistry 
values and additional 
testing completed 
ASAP (see 
Section 10.6.3); 
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.e 
≥3×ULN 
NA 
Yes 
≥8×ULN 
NA 
NA 
Need for hepatology 
consult to be 
discussed (required if 
ALT or AST 
≥8×ULN) 
Medical Monitor 
must be notified 
within 24 hours (eg, 
by laboratory alert) 
and study participant 
discussed with 
Medical Monitor 
ASAP. 
≥5×ULN 
(and ≥2× 
Baseline) and 
<8×ULN 
<2×ULN 
No 
Discussion with 
Medical Monitor 
required. 
Consider need for 
hepatology consult if 
there is no evidence 
of resolution (see 
Further investigation – 
immediate IMP 
discontinuation not 
required (see 
Section 10.6.2). 
 
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 10.6.3). 
Monitoring of liver 
chemistry values at least 
twice per week for 
2 weeks.e 
• Immediate IMP 
discontinuation 
required if liver 
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Table 10-2: Required investigations and follow up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or AST 
Total 
bilirubin 
Symptomsa of 
hepatitis or 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
follow-up 
requirements).c 
IMP discontinuation 
required if any of the 
following occur: 
• Study participant 
cannot comply with 
monitoring schedule. 
• Liver chemistry 
values continue to 
increase. 
• Liver chemistry 
values remain 
≥5×ULN (and 
≥2× Baseline) after 
4 weeks of 
monitoring without 
evidence of 
resolution. 
chemistry values 
continue to increase. 
After 2 weeks of 
monitoring liver 
chemistry values: 
• ALT or AST remains 
≥5×ULN <8×ULN, 
IMP should be 
temporarily withheld 
and study participant 
should undergo repeat 
test in 2 weeks. 
• Continue IMP if ALT 
or AST values 
<5×ULN; continue to 
monitor at least twice 
per week until values 
normalize, stabilize, or 
return to within 
Baseline values. 
• If ALT or AST remains 
≥5×ULN after second 
re-test, immediate IMP 
discontinuation 
required. 
• Continue to monitor 
until values normalize, 
stabilize, or return to 
within Baseline values.e 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; ASAP=as soon as possible; AST=aspartate aminotransferase; HCP=health care practitioner; 
IMP=investigational medicinal product; NA=not applicable; PDILI=potential drug-induced liver injury; ULN=upper limit of normal 
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Table 10-2: Required investigations and follow up for PDILI 
Laboratory value 
 
Immediate 
Follow up 
ALT or AST 
Total 
bilirubin 
Symptomsa of 
hepatitis or 
hypersensitivity 
Consultation 
requirements 
Actions 
Testing 
Evaluation 
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 study participant also has ≥2×ULN ALP, the possibility of an indication of biliary obstruction should be discussed with the Medical Monitor. 
c Details provided in Section 10.6.1. 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 Details are provided in Section 10.6.2. 
e 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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10.6.1 
Consultation with Medical Monitor and local hepatologist 
Potential drug-induced liver injury events require notification of the Medical Monitor or UCB 
Study Physician within 24 hours (eg, by laboratory alert), and the study participant must be 
discussed with the Medical Monitor or UCB Study Physician as soon as possible. If required, the 
study participant 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 10.6.3) and SAE report (if applicable). 
10.6.2 
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 7.1.1 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. 
10.6.2.1 
IMP restart/rechallenge 
Study participants who are immediately discontinued from IMP due to having met certain 
criteria for PDILI (as described in Section 7.1.1), but for whom an alternative diagnosis is 
confirmed, ie, DILI is excluded, can rarely restart IMP. Rechallenge with IMP can occur only if 
ALL of the following requirements are met: 
• The results of additional testing and monitoring described in Section 10.6.3 and 
Section 7.1.1.1 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). 
• No alternative treatment options are available to the study participant. 
• The study participant has shown clear therapeutic benefit from the IMP. 
• Study participant’s ALT or AST elevations do not exceed ≥5×ULN. 
• Study participant’s total bilirubin is <2×ULN. 
• Study participant has no signs or symptoms of hypersensitivity. 
• The rechallenge is approved by the UCB Study Physician and a hepatologist. The 
hepatologist must be external to UCB. It is recommended that the hepatologist be a local 
hepatology expert or the hepatologist treating the study participant. 
• Study participant agrees to the Investigator-recommended monitoring plan and understands 
his/her individual benefit/risk for restarting IMP and this is adequately documented. 
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10.6.3 
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 10-3 (laboratory measurements) and Table 10-4 (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 study participant indicates a requirement for 
other 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. 
Table 10-3: 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, blood urea nitrogen, creatinine 
Total bilirubin, ALP, AST, ALT, gamma-glutamyltransferase, total cholesterol, 
albumin 
If total bilirubin ≥1.5×ULN, obtain fractionated bilirubin to obtain % direct bilirubin 
Serum creatine phosphokinase and lactate dehydrogenase to evaluate possible muscle 
injury causing transaminase elevation 
Additional 
Prothrombin time/INRb 
Serum pregnancy testc 
PK sample 
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; FOCBP= female of 
childbearing potential; HBcAb-IgM=hepatitis B core antibody-IgM; HBsAg=hepatitis B surface antigen; 
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IgM=immunoglobulin M; INR=international normalized ratio; PDILI=potential drug-induced liver injury; 
PK=pharmacokinetics; RNA=ribonucleic acid; ULN=upper limit of normal 
a Tests in addition to the specified analytes may be performed based on the Investigator’s medical judgment and 
study participant history. 
b Measured only for study participants with ALT >8×ULN, 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 FOCBPs. 
The following additional information is to be collected: 
Table 10-4: PDILI information to be collected 
New or updated information 
• Concomitant prescriptions 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 
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10.7 
Appendix 7: Medical device AEs, adverse device effects, SAEs, 
and device deficiencies: definition and procedures for 
recording, evaluating, follow up, and reporting 
Not applicable. 
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10.8 
Appendix 8: Rapid alert procedures 
Not applicable. 
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10.9 
Appendix 9: Country-specific requirements 
Not applicable. 
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10.10 
Appendix 10: Abbreviations and trademarks 
ADAb 
antidrug antibodies 
AE 
adverse event 
AESI 
adverse event of special interest 
ALP 
alkaline phosphatase 
ALT 
alanine aminotransferase 
AST 
aspartate aminotransferase 
BP 
blood pressure 
BSA 
body surface area 
CAT 
computed axial tomography 
CI 
confidence interval 
CMH 
Cochran-Mantel-Haenszel 
CPM 
Clinical Project Manager 
CRO 
Contract Research Organization 
CTCAE 
Common Terminology Criteria for Adverse Events 
CV 
cardiovascular 
DLQI 
Dermatology Life Quality Index 
ECG 
electrocardiogram 
eCRF 
electronic Case Report Form 
C-SSRS 
Columbia Suicide Severity Rating Scale 
ePRO 
electronic patient-reported outcome 
FOCBP 
Female of child bearing potential 
GCP 
Good Clinical Practice 
GI 
gastrointestinal 
HBcAb 
anti-hepatitis B core antibody 
HBsAg 
hepatitis B surface antigen 
HCP 
healthcare practitioner 
HCV 
hepatitis C virus 
HIV 
human immunodeficiency virus 
IB 
Investigator’s Brochure 
IBD 
inflammatory bowel disease 
ICF 
Informed Consent Form 
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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 
LFT 
liver function test 
LOCF 
last observation carried forward 
LPLV 
last study participant’s last visit 
LTB 
latent tuberculosis 
LTBI 
latent tuberculosis infection 
mAb 
monoclonal antibody 
MAP 
Managed Access Program 
MI 
multiple imputation 
NSAID 
nonsteroidal anti-inflammatory drug 
NTMB 
nontuberculous mycobacterium 
PASI 
Psoriasis Area and Severity Index 
PDILI 
potential drug-induced liver injury 
PEOT 
Premature End of Treatment 
PHQ-9 
Patient Health Questionnaire 9 
PK 
pharmacokinetics 
PK-PPS 
Pharmacokinetics Per-Protocol Set 
PPS 
Per-Protocol Set 
PRN 
As needed, pro re nata 
PS 
Patient Safety 
PsA 
psoriatic arthritis 
P-SIM 
Patient Symptom and Impact Measure 
PSD 
patient symptom diary 
PSO 
psoriasis 
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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 
SFU 
Safety Follow-Up 
SIB 
suicidal ideation/behavior 
SoA 
Schedule of Activities 
SS 
Safety Set 
TB 
tuberculosis 
TEAE 
treatment-emergent adverse event 
TNF 
tumor necrosis factor 
ULN 
upper limit of normal 
WBC 
white blood cell 
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10.11 
Appendix 11: Protocol amendment history 
Amendment 1 (24 Mar 2021) 
Overall rationale for the amendment 
The purpose of this substantial amendment is to add text describing the option for participating 
in the Managed Access Program (MAP), add new withdrawal criterion for infections, revise 
wording for Pregnancy Followup Period, and to add text regarding adjudication committees.  
 
Section # and Name 
Description of Change 
Brief Rationale 
Section 1.1 Synopsis 
Figure 1.2 Schema 
Table 1.1 Schedule of Activities 
Section 4.1 Overall design 
Section 4.4 End of study definition 
Section 6.8 Treatment after the end 
of the study 
Added text to describe the option for 
a Managed Access Program 
Clarification 
Section 7.1.3 Treatment 
interuptions/temporary 
discontinued  
Added specific infection-related 
treatment interruptions to ensure that 
participants with serious or recurrent 
infections not responding to standard 
therapies are not exposed to 
immunomodulatory therapies until 
their infection is resolved. This is in 
line with most biologic therapies, 
including other anti-IL17s 
Clarification 
Section 9.7 Planned interim 
analysis and data monitoring 
Added text regarding interim 
analysis 
Clarification 
Section 10.1.5 Committee structure 
Added text regarding Adjudication 
Committees 
Clarification 
10.4 Appendix 4: Contraceptive 
guidance and collection of 
pregnancy information 
Changed the pregnancy follow up to 
30 days after the delivery date 
For consistency 
across other study 
related documents 
Throughout 
Minor editorial and document 
formatting revisions 
Minor and for clarity, 
therefore have not 
been summarized 
. 
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Amendment 2 (12 May 2021) 
Overall rationale for the amendment 
The purpose of this substantial amendment is in response to Korean Regulatory Authorities 
feedback regarding clarification of analysis sets and important protocol deviations. For 
consistency across other study related documents mean corpuscular hemoglobin concentrations 
(MCHC), chloride, gamma glutamyltransferase (GGT), lactate dehydrogenase (LDH), and lipid 
panel were added to the clinical chemistry assessments. 
The Managed Access Plan (MAP) is provided in this version of the protocol. The MAP was 
added in PS0032 Amendment 1 which was not submitted. 
Section # and Name 
Description of Change 
Brief Rationale 
Table 10-1: Protocol-required 
safety laboratory assessments 
Added, mean corpuscular 
hemoglobin concentrations 
(MCHC), chloride, gamma 
glutamyltransferase (GGT), lactate 
dehydrogenase (LDH), and lipid 
panel to clinical chemistry 
assessments 
For consistency 
across other study 
related documents 
Section 9.3.2 Analysis of the 
primary efficacy/primary endpoint 
Added more detail on the analysis 
sets to be used for primary 
endpoints. 
Updated per Agency 
feedback/request 
Section 9.3.3 Secondary efficacy 
endpoint analysis 
Added more detail on the analysis 
sets to be used for secondary 
endpoints. 
Updated per Agency 
feedback/request 
Section 9.5 Handling of protocol 
deviations 
Included detail of the process to be 
used to identify protocol deviations 
and exclusions from analysis sets. 
Added categories for the 
classification of important protocol 
deviations. 
Updated per Agency 
feedback/request 
Throughout 
Minor editorial and document 
formatting revisions 
Minor and for clarity, 
therefore have not 
been summarized 
 
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11 
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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:
ps0032-protocol-amend-3
Version:
1. 0
Document Number:
CLIN-000176898
Title:
PS0032 Protocol-Phase 3, placebo control, double-blind-Amendment 3
Approved Date:
20 Aug 2021
Document Approvals
Approval
Verdict: Approved
Name: 
Capacity: Clinical
Date of Signature: 20-Aug-2021 07:10:01 GMT+0000
Approval
Verdict: Approved
Name: 
Capacity: Clinical
Date of Signature: 20-Aug-2021 07:34:30 GMT+0000
Approval
Verdict: Approved
Name: 
Capacity: Clinical
Date of Signature: 20-Aug-2021 08:14:18 GMT+0000
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