A Multicenter, 48-week, Open-label Extension Study to Assess the Long-term Safety, Tolerability, and Efficacy of Bimekizumab in Adult Subjects With Moderate to Severe Chronic Plaque Psoriasis.
Phase: PHASE2
Conditions: Chronic Plaque Psoriasis
Sponsor: UCB Biopharma SRL

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PROTOCOL PS0018 AMENDMENT 3
A MULTICENTER, 48-WEEK, OPEN-LABEL EXTENSION 
STUDY TO ASSESS THE LONG-TERM SAFETY, 
TOLERABILITY, AND EFFICACY OF BIMEKIZUMAB IN ADULT 
SUBJECTS WITH MODERATE TO SEVERE CHRONIC
PLAQUE PSORIASIS
PHASE 2
EudraCT Number: 2016-002934-57
IND Number: 128707
Sponsor:
UCB Biopharma SPRL
Allée de la Recherche 60
B-1070 Brussels
BELGIUM
Protocol/Amendment number
Date
Type of 
amendment
Final Protocol
01 Aug 2016
Not applicable
Protocol Amendment 1
06 Sep 2016
Nonsubstantial
Protocol Amendment 2
23 Sep 2016
Not applicable
Protocol Amendment 3
16 Feb 2018
Substantial
Confidential Material
Confidential
This document is the property of UCB and may not – in full or in part – be passed on, 
reproduced, published, or otherwise used without the express permission of UCB.
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STUDY CONTACT INFORMATION
Sponsor
UCB Biopharma SPRL, Allée de la Recherche 60, B-1070 Brussels, Belgium
Sponsor Study Physician
Name:
Address:
UCB, 208 Bath Rd, Slough, Berkshire, SL1 3WE, UK
Phone:
Clinical Project Manager
Name:
Address:
UCB Celltech, 208 Bath Rd, Slough, Berkshire, SL1 3WE, UK
Phone:
Fax:
Clinical Trial Biostatistician
Name:
Address:
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, NC 
27617
Phone:
Fax:
Clinical Monitoring Contract Research Organization
Name:
PAREXEL International (IRL) Limited
Address:
One Kilmainham Square; Inchicore Road; Kilmainham; 
Dublin 8; Ireland
Phone:
+35 314739500
Fax:
+35 314739501
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SERIOUS ADVERSE EVENT REPORTING
Serious adverse event reporting (24h)
Fax
Europe and Rest of the World: +32 2 386 24 21
USA and Canada: +1 800 880 6949
or +1 866 890 3175
Email
Global: DS_ICT@ucb.com 
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TABLE OF CONTENTS
LIST OF ABBREVIATIONS....................................................................................................9
1
SUMMARY.....................................................................................................................11
2
INTRODUCTION ...........................................................................................................11
2.1 Psoriasis ...........................................................................................................................11
2.1.1
Global epidemiology of psoriasis ........................................................................12
2.1.2
Current treatments for psoriasis...........................................................................12
2.2 Bimekizumab ...................................................................................................................13
2.2.1
Clinical.................................................................................................................14
2.2.2
Nonclinical...........................................................................................................15
3
STUDY OBJECTIVES....................................................................................................16
3.1 Primary objective.............................................................................................................16
3.2 Secondary objectives .......................................................................................................16
4
STUDY VARIABLES.....................................................................................................16
4.1 Safety variables................................................................................................................16
4.1.1
Primary safety variable........................................................................................16
4.1.2
Other safety variables ..........................................................................................16
4.2 Pharmacokinetic variables ...............................................................................................16
4.3 Immunological variables..................................................................................................17
4.4 Efficacy variables.............................................................................................................17
5
STUDY DESIGN.............................................................................................................17
5.1 Study description .............................................................................................................17
5.1.1
Study duration per subject ...................................................................................18
5.1.2
Planned number of subjects and sites ..................................................................18
5.1.3
Anticipated regions and countries .......................................................................18
5.2 Schedule of study assessments.........................................................................................18
5.3 Schematic diagram...........................................................................................................21
5.4 Rationale for study design and selection of dose.............................................................23
6
SELECTION AND WITHDRAWAL OF SUBJECTS...................................................23
6.1 Inclusion criteria ..............................................................................................................23
6.2 Exclusion criteria .............................................................................................................24
6.3 Withdrawal criteria ..........................................................................................................25
6.3.1
PDILI IMP discontinuation criteria.....................................................................27
6.4 Study stopping rules.........................................................................................................27
7
STUDY TREATMENT...................................................................................................28
7.1 Description of investigational medicinal product............................................................28
7.2 Treatments to be administered.........................................................................................28
7.3 Packaging.........................................................................................................................28
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7.4 Labeling ...........................................................................................................................29
7.5 Handling and storage requirements..................................................................................29
7.6 Drug accountability..........................................................................................................29
7.7 Procedures for monitoring subject compliance................................................................29
7.8 Concomitant medication(s)/treatment(s)..........................................................................30
7.8.1
Permitted concomitant treatments (medications and therapies) ..........................30
7.8.2
Prohibited concomitant treatments (medications and therapies).........................30
7.9 Blinding............................................................................................................................31
7.10 Randomization and numbering of subjects......................................................................31
8
STUDY PROCEDURES BY VISIT ...............................................................................32
8.1 Baseline Visit...................................................................................................................32
8.2 Week 4 (±3 days); and Week 28 (±3 days)......................................................................33
8.3 Week 8 (±3 days); Week 16 (±3 days); and Week 40 (±3 days).....................................33
8.4 Week 12 (±3 days)...........................................................................................................34
8.5 Week 20 (±3 days); and Week 44 (±3 days)....................................................................35
8.6 Week 24 (±3 days)...........................................................................................................35
8.7 Week 32 (±3 days)...........................................................................................................36
8.8 Week 36 (±3 days)...........................................................................................................36
8.9 Week 48 (±3 days) Study Exit/Early Withdrawal ...........................................................37
8.10 SFU Visit (20 weeks after the last dose; -3/+7 days).......................................................37
8.11 Early Withdrawal Visit ....................................................................................................38
8.12 Unscheduled Visit............................................................................................................38
9
ASSESSMENT OF SAFETY..........................................................................................39
9.1 Adverse events.................................................................................................................39
9.1.1
Definition of AE ..................................................................................................39
9.1.2
Procedures for reporting and recording AEs .......................................................39
9.1.3
Description of AEs ..............................................................................................39
9.1.4
Follow up of AEs.................................................................................................40
9.1.5
Rule for repetition of an AE ................................................................................40
9.1.6
Pregnancy ............................................................................................................40
9.1.7
Suspected transmission of an infectious agent via a medicinal product..............41
9.1.8
Overdose of investigational medicinal product ...................................................41
9.1.9
Safety signal detection.........................................................................................41
9.2 Serious adverse events .....................................................................................................42
9.2.1
Definition of SAE................................................................................................42
9.2.2
Procedures for reporting SAEs ............................................................................42
9.2.3
Follow up of SAEs...............................................................................................43
9.3 Immediate reporting of AEs.............................................................................................43
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9.4 Anticipated SAEs.............................................................................................................43
9.5 Adverse events of special interest....................................................................................44
9.6 Adverse events for special monitoring ............................................................................44
9.7 Laboratory measurements................................................................................................44
9.7.1
Evaluation of PDILI ............................................................................................45
9.7.1.1
Consultation with Medical Monitor and local hepatologist ......................49
9.7.1.2
Immediate action: determination of IMP discontinuation.........................49
9.7.1.3
Testing: identification/exclusion of alternative etiology...........................49
9.7.1.4
Follow-up evaluation.................................................................................51
9.8 Other safety measurements..............................................................................................51
9.8.1
Assessment and management of TB and TB risk factors....................................51
9.8.1.1
TB assessment by IGRA ...........................................................................53
9.8.1.2
Chest x-ray for TB.....................................................................................54
9.8.1.3
TB questionnaire .......................................................................................54
9.8.1.4
TB management ........................................................................................54
9.8.2
Pregnancy testing.................................................................................................55
9.8.3
Vital signs ............................................................................................................55
9.8.4
12-lead ECGs.......................................................................................................55
9.8.5
Physical examination...........................................................................................55
9.8.6
Assessment of suicidal ideation and behavior.....................................................55
9.8.7
Data Monitoring Committee................................................................................56
10
ASSESSMENT OF PHARMACOKINETIC VARIABLES...........................................56
11
ASSESSMENT OF IMMUNOLOGICAL VARIABLES...............................................56
12
ASSESSMENT OF EFFICACY......................................................................................56
12.1 Psoriasis Area and Severity Index ...................................................................................56
12.2 Investigator’s Global Assessment....................................................................................57
12.3 BSA affected by psoriasis................................................................................................58
12.4 Hospital Anxiety and Depression Scale...........................................................................58
13
STUDY MANAGEMENT AND ADMINISTRATION.................................................58
13.1 Adherence to protocol......................................................................................................58
13.2 Monitoring .......................................................................................................................58
13.2.1
Definition of source data .....................................................................................59
13.2.2
Source data verification .......................................................................................59
13.3 Data handling...................................................................................................................59
13.3.1
eCRF completion.................................................................................................59
13.3.2
Database entry and reconciliation........................................................................60
13.3.3
Subject Screening and Enrollment log/Subject Identification Code list..............60
13.4 Termination of the study..................................................................................................60
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13.5 Archiving and data retention............................................................................................60
13.6 Audit and inspection ........................................................................................................61
13.7 Good Clinical Practices....................................................................................................61
14
STATISTICS ...................................................................................................................61
14.1 Definition of analysis sets................................................................................................61
14.2 Planned safety analyses....................................................................................................61
14.2.1
Primary safety analysis........................................................................................62
14.2.2
Other safety analyses ...........................................................................................62
14.3 Planned PK analyses........................................................................................................63
14.4 Planned immunological analyses.....................................................................................63
14.5 Planned efficacy analyses ................................................................................................63
14.6 Planned interim analysis and data monitoring.................................................................64
14.7 Determination of sample size...........................................................................................64
15
ETHICS AND REGULATORY REQUIREMENTS......................................................64
15.1 Informed consent .............................................................................................................64
15.2 Subject identification cards..............................................................................................65
15.3 IRBs and IECs..................................................................................................................65
15.4 Subject privacy.................................................................................................................66
15.5 Protocol amendments.......................................................................................................66
16
FINANCE, INSURANCE, AND PUBLICATION.........................................................66
17
REFERENCES ................................................................................................................66
18
APPENDICES .................................................................................................................69
18.1 Protocol Amendment 1 ....................................................................................................69
18.2 Protocol Amendment 2 ....................................................................................................71
18.3 Protocol Amendment 3 ....................................................................................................75
19
DECLARATION AND SIGNATURE OF INVESTIGATOR .......................................77
20
SPONSOR DECLARATION ..........................................................................................78
LIST OF TABLES
Table 5‒1:
Schedule of study assessments.........................................................................19
Table 7‒1:
Prohibited psoriasis medications during PS0018.............................................31
Table 9‒1:
Anticipated SAEs for the population of subjects with moderate to severe 
chronic plaque psoriasis...................................................................................44
Table 9‒2:
Laboratory measurements................................................................................45
Table 9-3:
Required investigations and follow-up for PDILI ...........................................47
Table 9-4:
PDILI laboratory measurements......................................................................50
Table 9-5:
PDILI information to be collected...................................................................51
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Table 12‒1:
Body areas for calculation of percent BSA for PASI ......................................57
LIST OF FIGURES
Figure 5‒1:
Schematic diagram...........................................................................................22
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LIST OF ABBREVIATIONS
AE
adverse event
AESM
adverse event for special monitoring
ALP
alkaline phosphatase
ALT
alanine aminotransferase
AST
aspartate aminotransferase
BSA
body surface area (affected by psoriasis) 
cAMP
cyclic adenosine monophosphate
CRO
Contract Research Organization
C-SSRS
Columbia-Suicide Severity Rating Scale
CTCAE
Common Terminology Criteria for Adverse Events
DMC
Data Monitoring Committee
EAER
exposure adjusted event rate
EAIR
exposure adjusted incidence rate
ECG
electrocardiogram
eCRF
electronic Case Report Form
EDC
electronic data capture
FAS
Full Analysis Set
FDA
Food and Drug Administration
GCP
Good Clinical Practice
GI
gastrointestinal
GMP
Good Manufacturing Practice
HADS
Hospital Anxiety and Depression Scale
HADS-A
Hospital Anxiety and Depression Scale-Anxiety
HADS-D
Hospital Anxiety and Depression Scale-Depression
HLT
high level term
IB
Investigator’s Brochure
IBD
Inflammatory Bowel Disease
ICH
International Council for Harmonisation
IEC
Independent Ethics Committee
IGA
Investigator’s Global Assessment
IGRA
interferon gamma release assay  
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IL
interleukin
IMP
investigational medicinal product
IRB
Institutional Review Board
iv
intravenous
IXRS
interactive voice or web response system
LTB
latent tuberculosis
mAb
monoclonal antibody
NSAID
nonsteroidal anti-inflammatory drug
NTMB
nontuberculous mycobacterium
PASI
Psoriasis Area and Severity Index
PDE4
phosphodiesterase 4
PDILI
potential drug-induced liver injury
PK
pharmacokinetics
PK-PPS
Pharmacokinetics Per-Protocol Set
PS
Patient Safety
PT
preferred term
Q4W
every 4 weeks
QOL
quality of life
SAE
serious adverse event
SAP
statistical analysis plan
sc
subcutaneous(ly)
SFU
Safety Follow-Up
SOC
system organ class
SOP
Standard Operating Procedure
SS
Safety Set
TB
tuberculosis
TEAE
treatment-emergent adverse event
TNF
tumor necrosis factor
ULN
upper limit of normal
VAS
visual analog scale
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1
SUMMARY
PS0018 is a multicenter, 48-week, open-label extension study to assess the long-term safety, 
tolerability, and efficacy of bimekizumab in eligible adult subjects with moderate to severe 
chronic plaque psoriasis who participated in PS0016. 
During the Open-Label Treatment Period, subjects will attend study visits at the site every 
4 weeks (Q4W) for study assessments and administration of bimekizumab (if applicable) by 
study site staff through Week 48. Following completion or early withdrawal from the 48-week 
Open-Label Treatment Period, subjects will return for a Safety Follow-Up (SFU) Visit at 
20 weeks after their last dose of bimekizumab. Subjects withdrawing early from the study will 
undergo the Early Withdrawal Visit assessments and will enter the SFU Period.
Bimekizumab will initially be administered at a dose of 160mg Q4W subcutaneously (sc) during
the 48-week Open-Label Treatment Period. There will be an option to increase the dose to 
320mg Q4W at the discretion of the Investigator if the subject’s Psoriasis Area and Severity 
Index (PASI) response is ≥50% to <75% reduction from the Baseline of PS0016 at Week 12 or 
later. If the subject’s disease is adequately controlled on the 320mg Q4W dose, they may return 
to 160mg Q4W at the discretion of the Investigator. The decision to return to 160mg Q4W
dosing should be based upon treatment response, tolerability, and Investigator discretion, with 
the aim to use the dosing regimen that achieves the optimal benefit-risk for each subject. If a 
subject does not achieve a PASI50 at Week 12 or later then they will be withdrawn from the 
study.
Up to 45 subjects are anticipated to enroll in PS0018 at approximately 15 sites in Europe and 
North America, with possible extension to other regions and countries as required in PS0016.
The primary objective of the study is to assess the long-term safety and tolerability of 
bimekizumab. Secondary objectives of the study are to assess the safety and tolerability of 
increasing the dose of bimekizumab from 160mg Q4W to 320mg Q4W; to assess the 
pharmacokinetics (PK) of bimekizumab; to assess the immunogenicity of bimekizumab; and to 
assess the efficacy of open-label bimekizumab 160mg Q4W administered over 48 weeks.
The primary safety variable is the incidence of treatment-emergent adverse events (TEAEs) 
adjusted by duration of subject exposure to treatment. The secondary safety variables are severity 
and frequency of TEAEs and change from Baseline of PS0016 in clinical laboratory values 
(chemistry, hematology, and urinalysis), vital signs, physical examination, and 12-lead 
electrocardiogram (ECG) results.
Pharmacokinetic variables are plasma concentrations of bimekizumab. The immunological 
variable is anti-bimekizumab antibody levels prior to and following study treatment. The 
efficacy assessments are PASI, Investigator’s Global Assessment (IGA), body surface area 
(BSA) affected by psoriasis, and the Hospital Anxiety and Depression Scale (HADS); a detailed 
list of efficacy variables is presented in Section 4.4.
2
INTRODUCTION
2.1
Psoriasis
Psoriasis is a common, chronic inflammatory disease characterized by a series of linked cellular 
changes in the skin: hyperplasia of epidermal keratinocytes, vascular hyperplasia and ectasia, and 
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infiltration of T lymphocytes, neutrophils, and other types of leukocytes in affected skin. Though 
the pathophysiology of psoriasis 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 (Kreuger and Ellis, 2005). 
There are a variety of forms including plaque, guttate, inverse, pustular, and erythrodermic. 
Plaque psoriasis is the most common, comprising approximately 80% to 90% of all cases. 
Approximately 17% of those with psoriasis have moderate to severe disease (Kurd et al, 2008).
In addition to the impact on skin, psoriasis has a multitude of psychosocial and emotional effects 
on patients, including increased self-consciousness, frustration, fatigue, depression, and suicidal 
ideation. As a result, patients frequently report sleeping problems, difficulties at work, problems 
interacting with family members, disrupted leisure activities, and sexual difficulties 
(Dowlatshahi et al, 2014; Gottlieb, 2005; Mukhtar et al, 2004; Ortonne, 2004; 
Krueger et al, 2001). 
A number of comorbidities have been associated with psoriasis, especially with more severe 
psoriasis. Psoriatic arthritis, cardiovascular disease, metabolic syndrome, chronic pulmonary 
disease, peptic ulcer disease, renal disease, and diabetes have all been demonstrated to have an 
increased prevalence in psoriasis patients (Yeung et al, 2013; Christophers et al, 2010; 
Gisondi et al, 2007; Gelfand et al, 2006).
2.1.1
Global epidemiology of psoriasis
Psoriasis affects approximately 3% of the adult US population (Rachakonda et al, 2014; 
Kurd and Gelfand, 2009) and its onset can begin at any age (Augustin et al, 2010; 
Icen et al, 2009). The reported worldwide incidence and prevalence of psoriasis varies greatly 
depending on age, gender, ethnicity, and geography primarily due to genetic and environmental 
factors. Estimates of incidence and prevalence include all types of psoriasis. Plaque psoriasis is 
the most common form of psoriasis therefore reported estimates of the magnitude of this 
condition are likely weighted heavily by this subtype. Both the incidence and prevalence of 
psoriasis are higher among Caucasians and those living in higher latitudes. Psoriasis affects 
approximately 2% to 4% of the population of western countries. Geographical differences are 
also influenced by case definition, study design, and the definition of prevalence 
(Parisi et al, 2013; Langley et al, 2005; Raychaudhuri and Gross, 2000).
2.1.2
Current treatments for psoriasis
Therapy for patients with psoriasis 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 chemophototherapy, methotrexate, the 
oral phosphodiesterase 4 (PDE4) inhibitor (apremilast), or biologic agents, such as tumor 
necrosis factor (TNF) antagonists, interleukin (IL) 12/23 inhibitors, and IL-17A inhibitors. The 
effectiveness of TNF inhibitors in the treatment of psoriasis has been demonstrated in many 
Phase 3 clinical studies and has led to the approval of multiple TNF inhibitors for use in patients 
with moderate to severe psoriasis. Interleukin inhibitors include secukinumab and ixekizumab, 
IL-17A inhibitors approved for treatment of moderate to severe psoriasis. Ustekinumab is an 
IL-12/23 antagonist approved for use in patients with moderate to severe psoriasis, and 
brodalumab, an IL-17 receptor antagonist, has completed pivotal Phase 3 studies in psoriasis. 
Standard therapies for psoriasis are listed below:
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
Topical steroids (eg, triamcinolone, mometasone, clobetasol, betamethasone, hydrocortisone) 
are generally used as first-line treatment of psoriasis. High-strength steroids are typically 
reserved for use on the arms and legs. Areas such as the face and skin folds (axillary, 
inguinal regions, etc) are usually treated with a low potency steroid. Chronic use of topical 
steroids can lead to corticosteroid-related side effects and is generally discouraged.

Vitamin D analogs (eg, calcipotriol and tacalcitol) are commonly used to treat mild to 
moderate psoriasis, and work best within the mild patients. They are safe but lack efficacy 
for many moderate to severe patients.

Chemophototherapy is a frequent option for moderate to severe patients, but the 
inconvenience of multiple treatment visits and varying efficacy limits its use in the market. 

Methotrexate is a systemic immunosuppressant and is used in moderate to severe patients. 
Toxicity concerns, particularly in older patients, are a major drawback.

Apremilast is an oral small-molecule inhibitor of PDE4 that is also approved for treatment of 
adults with moderate to severe plaque psoriasis. Phosphodiesterase 4 inhibitors work 
intracellularly to modulate a network of pro-inflammatory and anti-inflammatory mediators. 
Phosphodiesterase 4 is a cyclic adenosine monophosphate (cAMP)-specific PDE and the 
dominant PDE in inflammatory cells. Phosphodiesterase 4 inhibition elevates intracellular 
cAMP levels, which in turn down-regulates the inflammatory response by modulating the 
expression of TNFα, IL-23, IL-17, and other inflammatory cytokines.

Biologics, including TNFα inhibitors (adalimumab, etanercept, and infliximab), 
IL-12/23 inhibitors (ustekinumab), and IL-17A inhibitors are the treatment options of choice 
for patients with moderate to severe plaques psoriasis who are candidates for systemic 
therapy or phototherapy. These products are injected sc or delivered via intravenous (iv) 
infusion and while effective, TNFα inhibitors come with boxed warnings including the risk 
of serious infections and reports of lymphoma and malignancy in children and adolescent 
patients. The efficacy of TNFα inhibitors in treating psoriasis has been attributed to their 
inhibition of Th17-T cells. Different from the traditional systemic drugs that impact the entire 
immune system, biologics target specific parts of the immune system and offer reduced 
multi-organ toxicity and adverse effects associated with traditional treatments.
Secukinumab has been approved in the US and the EU for the treatment of moderate to 
severe plaque psoriasis in adult patients who are candidates for systemic therapy or 
phototherapy. Secukinumab is a monoclonal antibody (mAb) that inhibits the activity of the 
IL-17A isoform and is the first approved drug in its class. Clinical study results have shown 
that secukinumab achieves higher efficacy response levels than other drugs historically, 
demonstrating that IL-17 is a very effective target for the development of drugs for the 
treatment of psoriasis. 
2.2
Bimekizumab
Bimekizumab (also known as UCB4940) is an engineered, humanized, full-length 
immunoglobulin G1 mAb with high affinity for human IL-17A and IL-17F, important 
proinflammatory cytokines of the IL-17 family believed to play important roles in autoimmune 
and inflammatory diseases. Interleukin-17A has been shown to have a role in pathogenesis of 
several autoimmune disorders and IL-17F has been increasingly recognized to contribute to the 
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pathogenesis of a number of inflammatory diseases, including psoriasis, ulcerative colitis, 
asthma, ankylosing spondylitis, psoriatic arthritis, and rheumatoid arthritis. While anti-IL-17A 
antibodies have demonstrated efficacy in patients with psoriasis, psoriatic arthritis, and 
ankylosing spondylitis, as yet, no therapeutic approach is available that fully inhibits the activity 
of IL-17F. Bimekizumab selectively and potently inhibits the activity of both IL-17A and IL-17F 
isoforms in vitro. Therefore, it permits an evaluation of the potential for additional efficacy, that 
may be conferred by dual inhibition of both cytokines, in patients suffering from diseases in 
which both cytokines are active.
2.2.1
Clinical
Three clinical studies of bimekizumab have been completed: UP0008 in 39 subjects with mild to 
moderate plaque psoriasis, RA0124 in 30 healthy volunteers, and PA0007 in 53 subjects with 
psoriatic arthritis. Two studies (RA0123 and UP0031) are ongoing in subjects with moderate to 
severe rheumatoid arthritis and in healthy subjects, respectively. 
UP0008 was a Phase 1, single ascending dose study in adults with mild to moderate psoriasis 
affecting ≤5% BSA. In this blinded study, single doses of up to 640mg (approximately 8mg/kg 
in an 80kg adult) were evaluated without any safety concerns. A total of 26 subjects with 
psoriasis with less than 5% of body surface involvement were treated with a range of single iv 
doses from 8 to 640mg. There were no clinically relevant safety findings identified at any dose 
and all doses were well tolerated. The pre-specified exploratory assessment of disease activity 
showed clinically relevant and statistically significant improvements at the higher doses studied.
RA0124 was a Phase 1, open-label, parallel-group, single-dose study in healthy subjects. The 
primary objective of this study was to determine the absolute bioavailability of single sc doses of 
bimekizumab (80mg and 160mg). The secondary objectives were to evaluate the dose 
proportionality of bimekizumab 80mg and 160mg sc, and to evaluate the safety and tolerability 
of these sc doses and 160mg given by iv infusion. In RA0124, the absolute bioavailability was 
similar for the 2 doses tested (0.656 and 0.631 for the bimekizumab 80mg and 160mg sc doses, 
respectively). The PK of bimekizumab was linear in the tested dose range and the median t1/2
following sc administration was similar to that following iv administration (27.81 days and 
28.25 days for bimekizumab 160mg sc and 160mg iv, respectively).  
Bimekizumab has also been investigated in a Phase 1b, proof of concept, randomized, 
placebo-controlled, multiple dose study (PA0007). The primary objective of PA0007 was to 
assess the safety and PK of multiple dose administration of iv bimekizumab in subjects with 
psoriatic arthritis. Four active doses and a placebo were tested. Drug was administered as a 
loading dose at Week 0, and 2 additional doses were administered at Week 3 and Week 6. In 
each treatment group, subjects received a total of 3 doses of bimekizumab, administered every 
3 weeks as shown below:

80mg loading dose followed by 40mg at Weeks 3 and 6

160mg loading dose followed by 80mg at Weeks 3 and 6

240mg loading dose followed by 160 mg at Weeks 3 and 6

560mg loading dose followed by 320mg at Weeks 3 and 6
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The results of this study demonstrated that all doses of bimekizumab were well tolerated and 
there were no unexpected clinically relevant safety findings. 
Infections (mostly nasopharyngitis) were the most commonly reported events in both the active 
treatment and the placebo group. None of the infections were considered serious or required 
treatment with antibiotics. Two subjects in the active treatment group experienced 1 local 
candida infection each (oropharhyngitis and vulvovaginitis, respectively) that were nonserious 
and resolved with topical therapy. There was a reduction in mean neutrophil count in the active 
treatment group, although this drop was not clinically relevant and a clear relationship with dose 
or time was not evident. Some increases in liver function tests were reported, but none had a 
convincing relationship to exposure to study medication. The exploratory analysis showed 
clinically relevant improvement in activity of psoriatic arthritis and in skin involvement in those 
subjects with concomitant active psoriatic lesions.
Two additional studies of bimekizumab are ongoing. RA0123 is a Phase 2a, double-blind, 
randomized, placebo-controlled, multiple dose study to evaluate the safety, PK, 
pharmacodynamics, and efficacy of multiple doses of bimekizumab administered as add-on 
therapy to stable certolizumab pegol therapy in subjects with moderate to severe rheumatoid 
arthritis. UP0031 is a Phase 1 open-label, parallel-group, single-dose study to evaluate the 
relative bioavailability and tolerability of bimekizumab 160mg sc in healthy subjects.
Additional information on the clinical data for bimekizumab is available in the current version of 
the Investigator’s Brochure (IB).
The current study, PS0018, is a 48-week open-label extension study for eligible subjects who
participated in PS0016 (including subjects who relapse at Week 16 through 28 in PS0016), a 
Phase 2a, randomized, subject-blind, Investigator-blind study in adult subjects with moderate to 
severe chronic plaque psoriasis. In PS0016, subjects will be randomized 2:1 to receive the 
following study treatment regimens:

Treatment arm A: Bimekizumab 320mg administered sc at Baseline and Week 4, followed 
by placebo administration at Week 16

Treatment arm B: Bimekizumab 320mg administered sc at Baseline and Weeks 4 and 16
2.2.2
Nonclinical
Parallel inhibition of IL-17A and IL-17F has been shown to be efficacious in a variety of animal 
models of inflammatory disease. Intravenously administered bimekizumab was well tolerated in 
repeat dose toxicology studies in Cynomolgus monkeys with a no observed adverse effect level 
of 200mg/kg/week. The findings of note in toxicity studies were diarrhea related to infectious 
enteritis (observed in the single dose study) and asymptomatic mild colonic ulceration in a 
proportion of animals (in the repeat dose study); this latter finding was not associated with 
hematology abnormalities. Data suggest that bimekizumab has induced primary lesions to the 
mucosa-associated lymphoid tissue via a pharmacologically-related mechanism. In a second 
repeat-dose study, none of the minor apoptosis/necrosis findings observed in gut associated 
lymph nodes were revealed. In animals given the highest dose of bimekizumab in the study 
(20mg/kg/week), a slightly higher number of protozoa (Balantidium coli) was observed in the 
cecum and colon as compared to the control animals and low dose animals. Therefore gut 
associated lymph node lesions observed in the first study are considered to be accidental and/or 
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linked to exaggerated pharmacology and proliferation of Balantidium coli and is considered the 
consequence of a change in local mucosal immunity. To date, similar findings have not been 
seen in studies in humans.
Additional information on the nonclinical data for bimekizumab is available in the current 
version of the IB.
3
STUDY OBJECTIVES
3.1
Primary objective
The primary objective of the study is to assess the long-term safety and tolerability of 
bimekizumab.
3.2
Secondary objectives
Secondary objectives of the study are:

To assess the safety and tolerability of increasing the dose of bimekizumab from 160mg 
Q4W to 320mg Q4W for subjects with an inadequate response at Week 12

To assess PK of bimekizumab

To assess the immunogenicity of bimekizumab

To assess the efficacy of open-label bimekizumab 160mg Q4W administered over 48 weeks 
4
STUDY VARIABLES
4.1
Safety variables
4.1.1
Primary safety variable
The primary safety variable is the incidence of TEAEs adjusted by duration of subject exposure 
to treatment.
4.1.2
Other safety variables
Change from Baseline variables will be defined relative to the Baseline measurement from 
PS0016. 
The other safety variables are:

Severity and frequency of TEAEs 

Change from Baseline in clinical laboratory values (chemistry, hematology, and urinalysis) 

Change from Baseline in vital signs

Change from Baseline in physical examination

Change from Baseline in 12-lead ECG results
4.2
Pharmacokinetic variables
The PK variables are:

Plasma concentrations of bimekizumab
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4.3
Immunological variables
The immunological variable is anti-bimekizumab antibody levels prior to and following study 
treatment.
4.4
Efficacy variables
Change from Baseline variables will be defined relative to the Baseline measurement from 
PS0016.
The efficacy variables are listed below and will be evaluated at all scheduled visits in accordance 
with the schedule of assessments in Table 5‒1. 

PASI50, PASI75, PASI90, and PASI100 response

IGA response (Clear or Almost Clear with at least a 2 category improvement from Baseline
on a 5-point scale)

Absolute and percent change from Baseline in PASI score

Shift from Baseline in IGA score

Absolute and percent change from Baseline in the BSA affected by psoriasis

Change from Baseline in the HADS Anxiety (HADS-A) and Depression (HADS-D) scores

Percentage of subjects with scores below 8 in HADS-A and HADS-D (subjects with normal 
scores)
5
STUDY DESIGN
5.1
Study description
PS0018 is a multicenter, 48-week, open-label extension study to assess the long-term safety, 
tolerability, and efficacy of bimekizumab in eligible adult subjects with moderate to severe 
chronic plaque psoriasis who participated in PS0016. 
During the Open-Label Treatment Period, subjects will attend study visits at the site Q4W for 
study assessments and administration of bimekizumab by study site staff through Week 48. 
Following completion or early withdrawal from the 48-week Open-Label Treatment Period, 
subjects will return for a SFU Visit 20 weeks after their last dose of bimekizumab. Subjects 
withdrawing early from the study will undergo the Early Withdrawal Visit assessments and will 
enter the SFU Period.
Bimekizumab will initially be administered at a dose of 160mg Q4W subcutaneously (sc) during 
the 48 week Open Label Treatment Period. There will be an option to increase the dose to 320mg 
Q4W at the discretion of the Investigator if the subject’s PASI response is ≥50% to <75% 
reduction from the Baseline of PS0016 at Week 12 or later. If the subject’s disease is adequately 
controlled on the 320mg Q4W dose, they may return to 160mg Q4W at the discretion of the 
Investigator. The decision to return to 160mg Q4W dosing should be based upon treatment 
response, tolerability, and Investigator discretion, with the aim to use the dosing regimen that 
achieves the optimal benefit-risk for each subject. If a subject does not achieve a PASI50 at 
Week 12 or later then they will be withdrawn from the study.
A schedule of study assessments in presented in Table 5‒1.
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A study schematic diagram of PS0018 is presented in Figure 5‒1.
5.1.1
Study duration per subject
The study duration for each subject is estimated to be up to a maximum of 64 weeks:

Open-Label Treatment Period: up to 48 weeks

SFU Visit: 20 weeks after the last dose of bimekizumab
The end of the study is defined as the date of the last visit of the last subject in the study.
5.1.2
Planned number of subjects and sites
Up to 45 subjects are anticipated to enroll in PS0018 at approximately 15 sites.
5.1.3
Anticipated regions and countries
The regions planned for study conduct are Europe and North America, with possible extension to 
other regions and countries as required in PS0016.
5.2
Schedule of study assessments
A schedule of study assessments is presented in Table 5‒1.
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Table 5‒1:
Schedule of study assessments
Visit Week a
Protocol activity
PS0018
Baseline
Open-Label Treatment Period
Wk 
4
Wk 
8
Wk 
12
Wk 
16
Wk 
20
Wk 
24
Wk 
28
Wk 
32
Wk 
36
Wk 
40
Wk 
44
Wk 48/ 
WD
SFU b
Informed consent
X c
Inclusion/exclusion
X d
Physical exam e
X f
X
X
Body weight
X f
X
X
Vital signs g
X f
X
X
X
X
X
X
X
X
X
X
X
X
X
Hematology/biochemistry/urinalysish
X f
X
X
X
X
X
X
X
12-lead ECG
X f
X
X
X
Pregnancy testing i
X
X
X
X
X
X
X
X
X
X
X
X
X
X
C-SSRS
X f
X
X
X
X
X
X
X
X
X
X
X
X
X
IGRA TB test j
Xf
X
X
TB questionnaire
X f
X
X
X
X
Blood sample for bimekizumab plasma 
concentrations k
X f
X
X
X
X
X
X
X
X
Blood sample for anti-bimekizumab
antibodies k
X f
X
X
X
X
X
X
X
X
PASI
X f
X
X
X
X
X
X
X
X
X
X
X
X
X
IGA
X f
X
X
X
X
X
X
X
X
X
X
X
X
X
BSA
X f
X
X
X
X
X
X
X
X
X
X
X
X
HADS
X f
X
X
X
X
Concomitant medications
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Adverse events
X
X
X
X
X
X
X
X
X
X
X
X
X
X l
IXRS 
X
X
X
X
X
X
X
X
X
X
X
X
Bimekizumab administration m, n
X
X
X
X m
X m
X m
X m
X m
X m
X m
X m
X m
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Table 5‒1:
Schedule of study assessments
Visit Week a
Protocol activity
PS0018
Baseline
Open-Label Treatment Period
Wk 
4
Wk 
8
Wk 
12
Wk 
16
Wk 
20
Wk 
24
Wk 
28
Wk 
32
Wk 
36
Wk 
40
Wk 
44
Wk 48/ 
WD
SFU b
BSA=body surface area; C-SSRS=Columbia-Suicide Severity Rating Scale;ECG=electrocardiogram;  HADS=Hospital Anxiety and Depression Scale; 
IGA=Investigator’s Global Assessment; IGRA=interferon gamma release assay; IXRS=interactive voice or web response system; PASI=Psoriasis Area and 
Severity Index; Q4W=every 4 weeks; SFU=Safety Follow-Up; TB=tuberculosis; WD= withdrawal; Wk=week
a Visit windows of ±3 days from the first dose (Baseline) at all visits except SFU, which has a window of -3 and +7 days from scheduled visit date.
b The SFU Visit will occur 20 weeks after the last dose.
c Ensure that the informed consent for PS0018 was completed by the subject (must be done before any study assessments are performed for PS0018).
d To be performed prior to the first dose of open-label bimekizumab.
e Includes evaluation of signs and symptoms of active TB and risk for exposure to TB.
f The noted PS0018 Baseline assessments will be obtained at the final visit of PS0016 and do not need to be recorded on the case report form for this study.
g Vital signs (blood pressure, pulse rate, and temperature) are to be measured prior to blood sampling and prior to dosing, where applicable.
h  The FSH test should only be performed on postmenopausal females who have been postmenopausal for ≥1 year and last menstrual cycle occurred <2 year sago.
i Pregnancy testing will be urine testing at all visits except SFU, which will be a serum test.
j It is recommended that the QuantiFERON TB GOLD test be performed.
k All blood samples are to be taken prior to dosing.
l Including assessment for the development of different forms of psoriasis at the SFU visit.
m Bimekizumab will initially be administered at a dose of 160mg Q4W subcutaneously (sc) during the 48 week Open Label Treatment Period. There will be an 
option to increase the dose to 320mg Q4W at the discretion of the Investigator if the subject’s PASI response is ≥50% to <75% reduction from the Baseline of 
PS0016 at Week 12 or later. If the subject’s disease is adequately controlled on the 320mg Q4W dose, they may return to 160mg Q4W at the discretion of the 
Investigator. The decision to return to 160mg Q4W dosing should be based upon treatment response, tolerability, and Investigator discretion, with the aim to 
use the dosing regimen that achieves the optimal benefit-risk for each subject. If a subject does not achieve a PASI50 at Week 12 or later then they will be 
withdrawn from the study.
n Subjects should not receive their first dose in PS0018 until at least 4 weeks (+/-3 days) after their last dose in PS0016.
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5.3
Schematic diagram
A study schematic diagram of PS0018 is presented in Figure 5‒1.
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Figure 5‒1: Schematic diagram
BL=Baseline; PASI=Psoriasis Area and Severity Index; Q4W=every 4 weeks; sc=subcutaneously
a Bimekizumab will initially be administered at a dose of 160mg Q4W subcutaneously (sc) during the 48 week Open Label Treatment Period. There will be an 
option to increase the dose to 320mg Q4W at the discretion of the Investigator if the subject’s PASI response is ≥50% to <75% reduction from the Baseline of 
PS0016 at Week 12 or later. If the subject’s disease is adequately controlled on the 320mg Q4W dose, they may return to 160mg Q4W at the discretion of the 
Investigator. The decision to return to 160mg Q4W dosing should be based upon treatment response, tolerability, and Investigator discretion, with the aim to 
use the dosing regimen that achieves the optimal benefit-risk for each subject. If a subject does not achieve a PASI50 at Week 12 or later then they will be 
withdrawn from the study.
48-Week Open-Label 
Treatment Period
Eligible 
subjects 
who 
participated 
in PS0016
Week
PS0018
BL
4
24
8
12
16
20
Safety Follow-Up 
Visit
28
32
36
40
48
Bimekizumab 320mg Q4W sc
20 weeks after 
the last dose of 
bimekizumab
Dose increase to 320mg Q4W if ≥50% to
<PASI75 from PS0016 BL and at the 
Investigator’s discretion 
a
64 
Bimekizumab 160mg Q4W sc
44
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5.4
Rationale for study design and selection of dose
PS0018 is a 48-week open-label extension study for eligible subjects who participated in 
PS0016, a Phase 2a, randomized, subject-blind, Investigator-blind study in adult subjects with 
moderate to severe chronic plaque psoriasis. This study will allow the collection of further data 
on the long-term safety, tolerability, and efficacy of bimekizumab in this subject population and
will provide continued access to bimekizumab.
Bimekizumab will initially be administered at a dose of 160mg Q4W subcutaneously (sc) during 
the 48 week Open Label Treatment Period. There will be an option to increase the dose to 320mg 
Q4W at the discretion of the Investigator if the subject’s PASI response is ≥50% to <75% 
reduction from the Baseline of PS0016 at Week 12 or later. If the subject’s disease is adequately 
controlled on the 320mg Q4W dose, they may return to 160mg Q4W at the discretion of the 
Investigator. The decision to return to 160mg Q4W dosing should be based upon treatment 
response, tolerability, and Investigator discretion, with the aim to use the dosing regimen that 
achieves the optimal benefit-risk for each subject. If a subject does not achieve a PASI50 at 
Week 12 or later then they will be withdrawn from the study.
The rationale for the selection of the 160mg Q4W dose for this study is based on the following: 

The optimal therapeutic dose of bimekizumab will not yet be known at the time subjects 
begin entering PS0018 from PS0016.

The 160mg Q4W dose is within the range of doses that have already been explored by iv
administration. This dose was selected based on modeling using the currently available data 
and may be modified, if appropriate, as further data are collected on the optimal dose of 
bimekizumab.

The 160mg Q4W starting dose in PS0018 will provide data to evaluate the safety and 
efficacy of a dose reduction.
6
SELECTION AND WITHDRAWAL OF SUBJECTS
6.1
Inclusion criteria
To be eligible to participate in this study, all of the following criteria must be met:
1. An Institutional Review Board (IRB)/Independent Ethics Committee (IEC) approved written 
Informed Consent form is signed and dated by the subject. 
2. Subject is considered reliable and capable of adhering to the protocol and visit schedule 
according to the judgment of the Investigator.
3. Subject completes all dosing requirements in PS0016 without meeting any withdrawal 
criteria.
4. Female subjects must be postmenopausal (at least 1 year; to be confirmed hormonally at the 
PS0018 Baseline Visit, if less than 2 years since last menstrual period), permanently 
sterilized (eg, tubal occlusion, hysterectomy, bilateral salpingectomy) or, if of childbearing 
potential, must be willing to use a highly effective method of contraception up until 20 weeks 
after last administration of study medication (anticipated 5 half-lives), and have a negative 
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pregnancy test at Visit 1 (Baseline) and immediately prior to first dose. The following 
methods are considered highly effective when used consistently and correctly:

combined (estrogen and progestogen) hormonal contraception associated with inhibition 
of ovulation (oral, intravaginal, or transdermal) 

progestogen-only hormonal contraception associated with inhibition of ovulation (oral, 
injectable, or implantable)

intrauterine device 

intrauterine hormone-releasing system 

bilateral tubal occlusion

vasectomized partner 

sexual abstinence if it is in accordance with a subject’s preferred and common lifestyle. 
Subjects who use abstinence as a form of birth control must agree to abstain from 
heterosexual intercourse until 20 weeks after the last dose of study medication. Study 
personnel must confirm the continued use of abstinence is still in accordance with the 
subject’s lifestyle at regular intervals during the study.
Male subjects with a partner of childbearing potential must be willing to use a condom when 
sexually active, up till 20 weeks after the last administration of study medication (anticipated 
5 half-lives).
6.2
Exclusion criteria
Subjects are not permitted to enroll in the study if any of the following criteria are met:
1. Subject has previously participated in this study.
2. Female subjects who plan to become pregnant during the study or within 20 weeks following 
last dose of study medication. Male subjects who are planning a partner pregnancy during the 
study or within 20 weeks following the last dose.
3. Subject has any medical or psychiatric condition that, in the opinion of the Investigator, 
could jeopardize or would compromise the subject’s ability to participate in this study. Note: 
For any subject with an ongoing serious adverse event (SAE), or a history of serious 
infections (including herpes zoster or hospitalizations) in PS0016, the Medical Monitor must 
be consulted prior to the subject’s entry into PS0018.
4. Subject has any current sign or symptom that may indicate a medically significant infection.
5. Subject has current clinically active infection with Histoplasma, Coccidiodes, 
Paracoccidioides, Pneumocystis, tuberculosis (TB), nontuberculous mycobacteria (NTMB), 
Blastomyces, Aspergillus, or Candidiasis (systemic). Any subject diagnosed with 
Histoplasmosis, Coccidiodes, Paracoccidiodes, Pneumocystis, TB, NTMB, Blastomyces, 
Aspergillus, or Candidiasis (systemic) during PS0016 is excluded from PS0018 even if 
treatment has been completed.
6. Any subject who meets any withdrawal criteria in the feeder study (PS0016) is excluded 
from participating in the open-label extension study (PS0018).
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6.3
Withdrawal criteria
Subjects are free to withdraw from the study at any time, without prejudice to their continued 
care.
Subjects should be withdrawn from the study and will be asked to complete the Early 
Withdrawal Visit and SFU Visit (20 weeks after the last received dose) if any of the following 
events occur:
1. Subject withdraws his/her consent.
2. There is confirmation of a pregnancy in a female subject during the study, as evidenced by a 
positive pregnancy test.
3. The Sponsor or a regulatory agency requests withdrawal of the subject.
4. Subject 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. 
5. Subject develops erythrodermic, guttate, or pustular form of psoriasis.
6. Subjects considered to have either a suspected new latent tuberculosis (LTB) infection or 
who develop an active TB or NTMB infection during the study (including but not limited to, 
conversion demonstrated by interferon-gamma release assay [IGRA] or other diagnostic 
means) must be immediately discontinued from study medication; an Early Withdrawal Visit 
must be scheduled as soon as possible, but not later than the next regular visit.
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. 
7. Subject is noncompliant with the study procedures or medications in the opinion of the 
Investigator.
8. Subject uses prohibited concomitant medications that may present a risk to the safety of the 
subject in the opinion of the Investigator and/or the Medical Monitor.
9. Subject experiences an AE as described below:

Any Common Terminology Criteria for Adverse Events (CTCAE) Grade 3 and above AE 
that is assessed as related to study drug in the opinion of the Investigator.
◦
If the event is deemed to be not related to study drug by the Investigator, the subject 
may remain in the study after approval by the Medical Monitor. 

Any CTCAE Grade 2 event that is evaluated as related to study drug in the opinion of the 
Investigator, is persistent, and falls into any of the following system organ classes 
(SOCs): “Blood and lymphatic disorders,” “Cardiac disorders,” or “Vascular disorders.” 
◦
Persistent is defined as lasting 28 days or more, which spans at least 2 scheduled 
injections.
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10. Subject has a clinical laboratory value meeting the following criteria:

CTCAE Grade 3 and above: subjects must be withdrawn regardless of relationship to 
study drug or duration of event. 

CTCAE Grade 2
◦
Subjects may remain in the study if the event is transient. If a subject has a Grade 2 
laboratory abnormality, a retest is required within 1 to 2 weeks at a scheduled or 
unscheduled visit. If the repeat value is below Grade 2, the subject may receive the 
next scheduled study treatment. If the value on the repeat is still Grade 2 or above, a 
second repeat test must be performed and results made available prior to the next 
scheduled study treatment. If this second repeat value is still Grade 2 or above, the 
subject must be withdrawn.
11. Subject has active suicidal ideation as indicated by a positive response (“Yes”) to questions 4
or 5 or to the suicidal behavior questions of the “Since Last Visit” version of the self-rated 
Columbia-Suicide Severity Rating Scale (C-SSRS). The subject should be referred 
immediately to a Mental Healthcare Professional and must be withdrawn from the study.
12. Subjects with a HADS-D score ≥15 must be withdrawn. Any subject who develops a 
HADS-D score of >10 during the study should be referred immediately to a Mental 
Healthcare Professional for further evaluation and potential withdrawal by the Investigator.
13. Subject does not achieve a PASI50 at Week 12 or later following open-label treatment in 
PS0018.
14. Subjects with newly diagnosed Inflammatory Bowel Disease (IBD) or with IBD flares during 
the study must:
-
Be referred, as appropriate, to a healthcare professional treating IBD, such as a 
gastroenterologist
-
Discontinue the 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 judgment in deciding whether the subject should continue in the study and contact 
the Medical Monitor and UCB study physician to confirm the subject's suitability for 
continued participation in the study.
Investigators should attempt to obtain information on subjects in the case of withdrawal. For 
subjects considered as lost to follow-up, the Investigator should make an effort (at least 1 phone 
call and 1 written message to the subject), and document his/her effort (date and summary of the 
phone call and copy of the written message in the source documents), to complete the final 
evaluation. All results of these evaluations and observations, together with a narrative description 
of the reason(s) for removing the subject, must be recorded in the source documents. The eCRF 
must document the primary reason for withdrawal.
Investigators should contact the Medical Monitor, whenever possible, to discuss the withdrawal 
of a subject in advance.
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6.3.1
PDILI IMP discontinuation criteria
Subjects with potential drug-induced liver injury (PDILI) must be assessed to determine if 
investigational medicinal product (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: 

Subjects with either of the following:

ALT or AST ≥5xULN

ALT or AST ≥3xULN and coexisting total bilirubin ≥2xULN 

Subjects with ALT or AST ≥3xULN who exhibit temporally associated symptoms of 
hepatitis or hypersensitivity. Hepatitis symptoms include fatigue, nausea, vomiting, right 
upper quadrant pain or tenderness. Hypersensitivity symptoms include fever (without clear 
alternative cause), rash, or eosinophilia (ie, >5%).
The PDILI criterion below allows for subjects to continue on IMP at the discretion of the 
Investigator. 

Subjects with ALT or AST ≥3xULN (and ≥2x baseline) and <5xULN, total bilirubin 
<2xULN, and no eosinophilia (ie, ≤5%), with no fever, rash, or symptoms of hepatitis 
(eg, fatigue, nausea, vomiting, right upper quadrant pain or tenderness).
Evaluation of PDILI must be initiated as described in Section 9.7.1. If subjects are unable to 
comply with the applicable monitoring schedule, IMP must be discontinued immediately.
Investigators should attempt to obtain information on subjects in the case of IMP discontinuation 
to complete the final evaluation. Subjects with PDILI should not be withdrawn from the study 
until investigation and monitoring are complete. All results of these evaluations and 
observations, as well as the reason(s) for IMP discontinuation and subject withdrawal (if 
applicable), must be recorded in the source documents. The eCRF must document the primary 
reason for IMP discontinuation.
6.4
Study stopping rules
During the study, planned dosing and procedures may be discontinued or suspended for all 
subjects in any part of the study and appropriate follow up procedures established. Where it is 
possible to do so without threatening the safety of subjects, such discontinuation/suspension 
should be discussed with the UCB Study Physician prior to its implementation.
Possible reasons for discontinuation or suspension of the study include (but are not limited to):

A pattern of AEs occurs that contraindicates the further dosing of enrolled / additional 
subjects, including (but not limited to):

More than 1 subject meets any individual Withdrawal Criteria 6, 9, 10, 11 or 12 (as 
provided in Section 6.3), regardless of whether they met the same or different criteria.

Once a second subject meets any of those criteria, referral to the DMC may not be 
delayed while awaiting the outcome of either case.
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If the above criteria are reached, the DMC will meet as soon as possible to determine 
whether discontinuation or suspension of the study should occur, and to determine what 
investigations, analyses, procedural amendments, or other actions should occur, before 
making any recommendation regarding the possibility of recommencing the study.  Further 
details on the role of the DMC are provided in Section 9.8.7. 

If the Sponsor or its designees judges it necessary for medical, safety, regulatory, or any 
other reasons consistent with applicable laws, regulations, and GCP.
7
STUDY TREATMENT
7.1
Description of investigational medicinal product
The IMP used in this study is bimekizumab. 
Bimekizumab will be supplied as a clear to opalescent, colorless to slightly brown, sterile, 
preservative free solution in 2mL Type I, colorless glass vials (1.0mL extractable volume) closed 
with a rubber stopper and sealed with an aluminum cap overseal. Each single-use dose vial 
contains 160mg/mL bimekizumab in 55mM sodium acetate, 220mM glycine and 0.04% (w/v) 
polysorbate 80 at pH 5.0.
Further details of the study medication and specifications are provided in the IMP Handling 
Manual.
7.2
Treatments to be administered
During the Treatment Period, all subjects will receive bimekizumab 160mg Q4W sc 
administered for up to 48 weeks in an open-label manner. Subjects should not receive their first 
dose in PS0018 until at least 4 weeks (+/-3 days) after their last dose in PS0016. At the discretion 
of the Investigator, and if the subject does not achieve a PASI75 response (75% reduction in the 
PASI score from the Baseline of PS0016) at Week 12, the bimekizumab dose in PS0018 may be 
increased to 320mg Q4W sc. If the subject’s disease is adequately controlled on the 320mg Q4W 
dose, they may return to 160mg Q4W. The decision to return to 160mg Q4W dosing should be 
based upon treatment response, tolerability, and Investigator discretion, with the aim to use the 
dosing regimen that achieves the optimal benefit-risk for each subject.
The study medication is to be administered in the clinic by study site staff as 1 sc injection for 
the 160mg dose or 2 sc injections for the 320mg dose. Suitable areas for sc injections are the 
lateral abdominal wall and upper outer thigh. Injection sites should be rotated and injections 
should not be given into areas where the skin is tender, bruised, red, or hard. 
The minimum time between doses should be no less than 24 days and no more than 32 days for 
Q4W dosing.
An IMP Handling Manual will be provided to each site containing instructions regarding drug 
preparation and dosing.
7.3
Packaging
Bimekizumab will be packaged and labeled according to Good Manufacturing Practice (GMP) 
guidelines and applicable laws or regulations. It will be suitably packaged in such a way as to 
protect the product from deterioration during transport and storage. Further information 
regarding storage and transport conditions are provided in the IMP Handling Manual.
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7.4
Labeling
Clinical drug supplies will be labeled in accordance with the current International Council for
Harmonisation (ICH) guidelines on Good Clinical Practice (GCP) and GMP and will include any 
locally required statements. If necessary, labels will be translated into the local language.
7.5
Handling and storage requirements
The IMP must be stored under refrigerated conditions (2ºC to 8ºC) and protected from light. The 
study drug must not be frozen. 
The Investigator (or designee) is responsible for the safe and proper storage of IMP at the site. 
Investigational medicinal product stored by the Investigator is to be kept in a secured area with 
limited access according to the storage conditions mentioned on the label.
Appropriate storage conditions must be ensured by controlling the temperature (eg, room, 
refrigeration unit) and by completion of a temperature log in accordance with local requirements 
on a regular basis per study manuals, showing actual and minimum/maximum temperatures
reached over the time interval.
Study drug will be shipped to the study sites in temperature controlled containers. Out-of-range 
shipping or storage conditions must be brought to the attention of the Sponsor or designee, as per 
instructions contained in the IMP Handling Manual. Authorization to use any out-of-range IMP 
must be documented and received prior to dispensing or administering the IMP at the study site.
7.6
Drug accountability
A Drug Accountability form will be used to record IMP dispensing and return information on a 
by-subject basis and will serve as source documentation during the course of the study. Details of 
any IMP lost, damaged (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.
The Investigator (or designee) is responsible for retaining all used, unused, and partially used 
containers of IMP until returned or destroyed.
The Investigator may assign some of the Investigator’s duties for drug accountability at the study 
site to an appropriate pharmacist/designee.
The Investigator must ensure that the IMP is used only in accordance with the protocol.
Periodically, and/or after completion of the clinical phase of the study, all used (including empty 
containers), partially used, unused, damaged, and/or expired IMP must be reconciled and either 
destroyed at the site according to local laws, regulations, and UCB SOPs or returned to UCB (or 
designee). Onsite destruction of used kits only may be allowed with prior approval from the 
Sponsor or designee after reconciliation. Investigational medicinal product intended for the study 
cannot be used for any other purpose than that described in this protocol.
7.7
Procedures for monitoring subject compliance
During the treatment period of this study, study medication 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.
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7.8
Concomitant medication(s)/treatment(s)
All concomitant medications, including over the counter products, herbal, traditional remedies, 
vitamin/mineral supplements, other dietary supplements, “nutraceuticals,” and hormones must be 
recorded in the subject’s source documentation (eg, clinical chart) and on the eCRF. This record 
should include the name of the drug, the dose, the route and date(s) of administration, and the 
indication for use.
The Investigator should examine the acceptability of all concomitant procedures, medications, 
topical preparations, and dietary supplements not explicitly prohibited in this study, and if 
necessary, discuss with the Medical Monitor. 
In order to ensure that appropriate concomitant therapy is administered, subjects will be 
instructed to consult with the Investigator prior to taking any medication (either 
self-administered nonprescription drugs or prescription therapy prescribed by another physician).
7.8.1
Permitted concomitant treatments (medications and therapies)
Topical medications
Subjects may continue to use topical moisturizers or emollients, bath oils, or oatmeal bath 
preparations for skin conditions during the study, as needed. Over-the-counter shampoos for the 
treatment of psoriasis of the scalp are also permitted. 
Subjects will be allowed to use topical medications (corticosteroids, retinoids, Vitamin D analogs 
coal tar, etc) as needed during this open-label extension. 
Other medications
Subjects who were already receiving an established nonsteroidal anti-inflammatory drug 
(NSAID) regimen during PS0016 may continue their use during this study. However, initiation 
of, or increase in dosage of, NSAIDs during the study (especially in subjects with a history of 
gastrointestinal [GI] intolerance to NSAIDs or a history of GI ulceration) should be done with 
caution. Intra-articular injections for arthritis of the knee are allowed.
Subjects who were already receiving an established anti-depressant regimen during PS0016 may 
continue their use during this study.
7.8.2
Prohibited concomitant treatments (medications and therapies)
The list of prohibited concomitant medications is provided Table 7‒1.
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Table 7‒1:
Prohibited psoriasis medications during PS0018
Drug
Systemic retinoids
Systemic treatment (non-biological):
systemic immunosuppressant agents (eg, methotrexate, cyclosporine, azathioprine, thioguanine)
systemic fumarate
systemic corticosteroids
phototherapy or chemophototherapy
Anti-TNFs:
infliximab (including biosimilar), golimumab
etanercept (including biosimilar)
certolizumab pegol
adalimumab (including biosimilar)
Other biologics and other systemic therapies:
apremilast
ustekinumab
Anti-IL-17 therapy
Any other antipsoriatic agent (systemic)
Any other antipsoriatic agent (topical) under investigation
IL=interleukin; TNF=tumor necrosis factor
Subjects who take prohibited medications may be withdrawn from study treatment but followed 
until the SFU Visit. The decision to withdraw a subject for taking prohibited medications should 
be made in consultation with the Medical Monitor. 
Vaccines
Administration of live (including attenuated) vaccines is not allowed during the conduct of the 
study or for 20 weeks after the last dose of study drug. Administration of inactivated vaccines is 
allowed during the study at the discretion of the Investigator.
7.9
Blinding
This is an open-label extension study and no blinding will be performed. All subjects’ treatment 
assignments during PS0016 will remain blinded until database lock of PS0016.
7.10
Randomization and numbering of subjects
This is an open-label extension study and no randomization will be performed. All subjects will 
receive bimekizumab 160mg Q4W sc with an option to increase the dose to 320mg Q4W at the 
discretion of the Investigator (see Section 7.2 for further details).
Subjects will continue with the 5-digit subject numbers assigned by the interactive voice or web 
response system (IXRS) in the preceding study.
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8
STUDY PROCEDURES BY VISIT
Table 5‒1 (schedule of study assessments) provides a general overview of study assessments. A 
list of procedures to be completed at each visit is provided in the sections that follow. 

Visit windows of ±3 days on either side of the scheduled dosing are permitted for all visits 
other than the SFU Visit (see below); however, the Investigator should try to keep the 
subjects on the original dosing schedule. The window of ±3 days is relative to the first dose 
(Baseline) and applicable for all subsequent visits. Changes to the dosing schedule outside of 
the 3-day window must be discussed with the Medical Monitor.

The minimum time between doses should be no less than 24 days and no more than 32 days 
for Q4W dosing.

For the SFU Visit (20 weeks after the last dose), the visit should occur no more than 3 days
prior to the scheduled visit date and within 7 days after the scheduled visit date 
(-3 days/+7 days).
8.1
Baseline Visit
The Baseline assessments noted with an * will be obtained at the final visit of PS0016 and do not 
need to be recorded on the eCRF for this study.
All procedures or assessments will be performed prior to administration of study drug, unless 
otherwise noted. The following procedures or assessments will be performed:

Ensure that a separate Informed Consent Form was completed by the subject for PS0018
(must be done prior to any PS0018 study procedures)

Confirm that a TB test (IGRA) was performed at the final visit of PS0016 and the results 
were negative

Assessment of inclusion/exclusion criteria

Vital signs (blood pressure, pulse rate, and temperature)*

Body weight*

Physical examination*

Record 12-lead ECG*

C-SSRS*

TB questionnaire*

PASI*

IGA*

BSA*

HADS*

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)*
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
Bimekizumab plasma concentration*

Anti-bimekizumab antibodies*

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)*

Urine pregnancy test for women of childbearing potential*

Concomitant medications

Record adverse events (AEs)

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.2
Week 4 (±3 days); and Week 28 (±3 days)
All procedures or assessments will be performed prior to administration of study drug, unless 
otherwise noted. The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

PASI

IGA

BSA

Obtain blood samples for:

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine sample for: 

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.3
Week 8 (±3 days); Week 16 (±3 days); and Week 40 (±3 days)
All procedures or assessments will be performed prior to administration of study drug (if 
applicable), unless otherwise noted. The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

PASI
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
IGA

BSA

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.4
Week 12 (±3 days)
The following procedures or assessments will be performed prior to administration of study drug
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain blood samples for:

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine sample for: 

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS
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
Study medication administration (after all other visit assessments are completed)
8.5
Week 20 (±3 days); and Week 44 (±3 days)
The following procedures or assessments will be performed prior to administration of study drug 
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

PASI

IGA

BSA

Obtain urine sample for: 

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.6
Week 24 (±3 days)
The following procedures or assessments will be performed prior to administration of study drug 
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

Record 12-lead ECG

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Obtain urine samples for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications
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
Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.7
Week 32 (±3 days)
All procedures or assessments will be performed prior to administration of study drug (if 
applicable), unless otherwise noted. The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

PASI

IGA

BSA

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.8
Week 36 (±3 days)
The following procedures or assessments will be performed prior to administration of study drug 
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain urine sample for: 

Urine pregnancy test for women of childbearing potential
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
Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
8.9
Week 48 (±3 days) Study Exit/Early Withdrawal
The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

Body weight

Physical examination

Record 12-lead ECG

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain blood samples for:

TB test (IGRA; QuantiFERON TB GOLD test is recommended)

Standard safety laboratory tests (hematology and biochemistry)

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs
8.10
SFU Visit (20 weeks after the last dose; -3/+7 days)
The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

Body weight

Physical examination
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
C-SSRS

Record 12-lead ECG

PASI

IGA

Obtain blood samples for:

TB test (IGRA; QuantiFERON TB GOLD test is recommended)

Standard safety laboratory tests (hematology and biochemistry)

Serum pregnancy test for women of childbearing potential

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)

Concomitant medications

Record AEs (including assessment for development of other forms of psoriasis)
8.11
Early Withdrawal Visit
Subjects withdrawing early from the study (see Section 6.3) will undergo the same assessments 
as the Week 48 Visit (see Section 8.9) and will enter the SFU Period.
8.12
Unscheduled Visit
At the Investigator’s discretion, an Unscheduled Visit may be completed at any time during the 
study, but prior to the SFU Visit, if deemed necessary for the subject’s safety and well-being.
If an additional visit (or 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 additional visit (or 
unscheduled visit) is conducted for reasons other than safety or efficacy concerns 
(eg, replacement of lost medication, repeated collection of a laboratory specimen due to 
collection or analysis issues), a C-SSRS will not be required at these visits.
At this visit, any of the following assessments may be performed, depending on the reason for 
the visit:

Vital signs

Physical examination

Record 12-lead ECG 

C-SSRS

If medically indicated, obtain blood sample(s) for:

Standard safety laboratory tests (hematology and biochemistry) 

The blood sample may also be used for PK assessments, if needed
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
Obtain urine sample for standard safety laboratory tests (urinalysis; including urine 
pregnancy test)

Concomitant medications

Record AEs
9
ASSESSMENT OF SAFETY
9.1
Adverse events
9.1.1
Definition of AE
An AE is any untoward medical occurrence in a patient or clinical investigation subject 
administered a pharmaceutical product that does not necessarily have a causal relationship with 
this treatment. An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease temporally associated with the use of a 
medicinal (investigational) product, whether or not related to the medicinal (investigational) 
product.
In order to ensure complete safety data collection, all AEs occurring during the study (ie, after 
the signing of the Informed Consent form), including any pretreatment and posttreatment periods 
required by the protocol, must be reported in the eCRF even if no IMP was taken but specific 
study procedures were conducted. This includes all AEs not present prior to the initial visit and 
all AEs that recurred or worsened after the initial visit.
Signs or symptoms of the condition/disease for which the IMP is being studied should be 
recorded as AEs only if their nature changes considerably or their frequency or intensity 
increases in a clinically significant manner as compared to the clinical profile known to the 
Investigator from the subject’s history or the Baseline Period.
9.1.2
Procedures for reporting and recording AEs
The subject will be given the opportunity to report AEs spontaneously. A general prompt will 
also be given at each study visit to detect AEs. For example:
“Did you notice anything unusual about your health (since your last visit)?”
In addition, the Investigator should review any self-assessment procedures employed in the 
study.
9.1.3
Description of AEs
When recording an AE, the Investigator should use the overall diagnosis or syndrome using 
standard medical terminology, rather than recording individual symptoms or signs. The eCRF 
and source documents should be consistent. Any discrepancies between the subject’s own words 
on his/her own records and the corresponding medical terminology should be clarified in the 
source documentation.
When recording the severity of an AE in the CRF (ie, mild, moderate, or severe), the Investigator 
must refer to the CTCAE Version 4 
(http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm). Details for 
completion of the AE eCRF (including judgment of severity and relationship to IMP) are 
described in the eCRF Completion Guidelines.
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9.1.4
Follow up of AEs
An AE should be followed until it has resolved, has a stable sequelae, the Investigator
determines that it is no longer clinically significant, or the subject is lost to follow up. Further 
details regarding follow up of PDILI events are provided in Section 9.7.1.4.
If an AE is ongoing at the end of the study for a subject, follow up should be provided until 
resolution/stable level of sequelae is achieved, or until the Investigator no longer deems that it is 
clinically significant, or until the subject is lost to follow up. If no follow up is provided, the 
Investigator must provide a justification. The follow up will usually be continued for 20 weeks
after the subject has discontinued his/her IMP.
9.1.5
Rule for repetition of an AE
An increase in the intensity of an AE should lead to the repetition of the AE being reported with:

The outcome date of the first AE that is not related to the natural course of the disease being 
the same as the start date of the repeated AE, and the outcome of “worsening”

The AE verbatim term being the same for the first and repeated AE, so that the repeated AE 
can be easily identified as the worsening of the first one
9.1.6
Pregnancy
If an Investigator is notified that a subject has become pregnant after the first intake of any IMP, 
the Investigator must immediately notify UCB’s Patient Safety (PS) department by providing the 
completed Pregnancy Report and Outcome form (for contact details see SAE reporting
information at the beginning of this protocol). The subject should be withdrawn from the study 
as soon as pregnancy is known (by positive pregnancy test), and the following should be 
completed:

The subject should return for an Early Withdrawal Visit.

The subject should immediately stop the intake of the IMP. 

A SFU Visit should be scheduled 20 weeks after the subject has discontinued her IMP.
The Investigator must inform the subject of information currently known about potential risks 
and about available treatment alternatives.
The pregnancy will be documented on the Pregnancy Report and Outcome form provided to the 
Investigator. The progression of the pregnancy and the eventual birth (if applicable) must be 
followed up using the Pregnancy Report and Outcome form in which the Investigator has to 
report on the health of the mother and of the child. Every reasonable attempt should be made to 
follow the health of the child for 30 days after birth for any significant medical issues. In certain 
circumstances, UCB may request that follow up is continued for a period longer than 30 days. If 
the subject is lost to follow up and/or refuses to give information, written documentation of 
attempts to contact the subject needs to be provided by the Investigator and filed at the site. 
UCB’s PS department is the primary contact for any questions related to the data collection for 
the pregnancy, eventual birth, and follow up.
In cases where the partner of a male subject enrolled in a clinical study becomes pregnant, the 
Investigator or designee is asked to contact the subject to request consent of the partner via the 
Partner Pregnancy Consent form that has been approved by the responsible IRB/IEC and should 
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be available in the Investigator site file. In case of questions about the consent process, the 
Investigator may contact the UCB/Contract Research Organization (CRO) contract monitor for 
the study. The Investigator will complete the Pregnancy Report and Outcome form and send it to 
UCB’s PS department (for contact details see SAE reporting information at the beginning of this 
protocol) only after the partner has agreed that additional information can be captured and has 
provided the signed Partner Pregnancy Consent form. UCB’s PS department is also the primary 
contact for any questions related to the data collection for the partner pregnancy, eventual birth, 
and follow up.
A pregnancy becomes an SAE in the following circumstances: miscarriage, abortion (elective or 
spontaneous), unintended pregnancy after hormonal contraceptive failure (if the hormonal 
contraceptive was correctly used), ectopic pregnancy, fetal demise, or any congenital 
anomaly/birth defect of the baby. Those SAEs must be additionally reported using the 
Investigator SAE Report form.
9.1.7
Suspected transmission of an infectious agent via a medicinal 
product
For the purposes of reporting, any suspected transmission of an infectious agent via a medicinal 
product should be considered as an SAE; such cases must be reported immediately, recorded in 
the AE module of the eCRF, and followed as any other SAE. Any organism, virus, or infectious 
particle (eg, prion protein transmitting transmissible spongiform encephalopathy), pathogenic or 
nonpathogenic, is considered an infectious agent.
9.1.8
Overdose of investigational medicinal product
Excessive dosing (beyond that prescribed in the protocol and including overdose) should be 
recorded in the eCRF. Any SAE or nonserious AE associated with excessive dosing must be 
followed as any other SAE or nonserious AE. These events are only considered AEs or SAEs if 
there are associated clinical signs and symptoms or if the act of taking the excess medicine itself 
is an AE or SAE (eg, suicide attempt).
9.1.9
Safety signal detection
Selected data from this study will be reviewed periodically to detect as early as possible any 
safety concern(s) related to the IMP so that Investigators, clinical study subjects, regulatory 
authorities, and IRBs/IECs will be informed appropriately and as early as possible.
In addition, an independent Data Monitoring Committee (DMC) will periodically review and 
monitor the safety data from this study and advise UCB. Details are provided in the DMC 
Charter. A Cardiovascular Adjudication Committee will also periodically review and monitor the 
safety data from this study and advise UCB. Details are provided in the Cardiovascular
Adjudication Committee Charter.
The Study Physician or medically qualified designee/equivalent will conduct an ongoing review 
of SAEs and perform ongoing SAE reconciliations in collaboration with the PS representative.
As appropriate for the stage of development and accumulated experience with the IMP, 
medically qualified personnel at UCB may identify additional safety measures (eg, AEs, vital 
signs, laboratory, or ECG results) for which data will be periodically reviewed during the course 
of the study.
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9.2
Serious adverse events
9.2.1
Definition of SAE
Once it is determined that a subject experienced an AE, the seriousness of the AE must be 
determined. An SAE must meet 1 or more of the following criteria:

Death

Life-threatening
(Life-threatening does not include a reaction that might have caused death had it occurred in 
a more severe form.)

Significant or persistent disability/incapacity

Congenital anomaly/birth defect (including that occurring in a fetus)

Important medical event that, based upon appropriate medical judgment, may jeopardize the 
patient or subject and may require medical or surgical intervention to prevent 1 of the other 
outcomes listed in the definition of serious
(Important medical events may include, but are not limited to, potential Hy’s Law [see 
Section 9.5], allergic bronchospasm requiring intensive treatment in an emergency room or at 
home, blood dyscrasias that do not result in inpatient hospitalization, or the development of 
drug dependency or drug abuse.)

Initial inpatient hospitalization or prolongation of hospitalization
(A patient admitted to a hospital, even if he/she is released on the same day, meets the 
criteria for the initial inpatient hospitalization. An emergency room visit that results in 
admission to the hospital would also qualify for the initial inpatient hospitalization criteria. 
However, emergency room visits that do not result in admission to the hospital would not 
qualify for this criteria and, instead, should be evaluated for 1 of the other criteria in the 
definition of serious [eg, life-threatening adverse experience, important medical event].
Hospitalizations for reasons not associated with the occurrence of an AE [eg, preplanned 
surgery or elective surgery for a pre-existing condition that has not worsened or manifested 
in an unusual or uncharacteristic manner] do not qualify for reporting. For example, if a 
subject has a condition recorded on his/her medical history and later has a preplanned surgery 
for this condition, it is not appropriate to record the surgery or hospitalization as an SAE, 
since there is no AE upon which to assess the serious criteria. Please note that, if the 
pre-existing condition has worsened or manifested in an unusual or uncharacteristic manner, 
this would then qualify as an AE and, if necessary, the seriousness of the event would need to 
be determined.)
Note: Confirmed active TB is always to be considered as an SAE and must be captured on an 
SAE Report Form and provided to the Sponsor in accordance with SAE reporting requirements.
9.2.2
Procedures for reporting SAEs
If an SAE is reported, UCB must be informed within 24 hours of receipt of this information by 
the site (see contact information for SAE reporting listed in the SAE Reporting section at the 
front of the protocol). The Investigator must forward to UCB (or its representative) a duly 
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completed “Investigator SAE Report Form for Development Drug” (SAE report form) provided 
by UCB, even if the data are incomplete, or if it is obvious that more data will be needed in order 
to draw any conclusions. Information recorded on this form will be entered into the global safety 
database.
An Investigator SAE report form will be provided to the Investigator. The Investigator SAE 
Report form must be completed in English. 
It is important for the Investigator, when completing the SAE report form, to include the 
assessment as to a causal relationship between the SAE and the IMP administration. This insight 
from the Investigator is very important for UCB to consider in assessing the safety of the IMP 
and in determining whether the SAE requires reporting to the regulatory authorities in an 
expedited manner.
Additional information (eg, autopsy or laboratory reports) received by the Investigator must be 
provided within 24 hours. All documents in the local language must be accompanied by a 
translation in English, or the relevant information included in the same document must be 
summarized in the Investigator SAE report form.
The Investigator is specifically requested to collect and report to UCB (or its representative) any 
SAEs (even if the Investigator is certain that they are in no way associated with the IMP), up to 
30 days from the end of the study for each subject, and to also inform participating subjects of 
the need to inform the Investigator of any SAE within this period. Serious AEs that the 
Investigator thinks may be associated with the IMP must be reported to UCB regardless of the 
time between the event and the end of the study.
Upon receipt of the SAE report form, UCB will perform an assessment of expectedness of the 
reported SAE. The assessment of the expectedness of the SAE is based on the IB.
9.2.3
Follow up of SAEs
An SAE should be followed until it has resolved, has a stable sequelae, the Investigator
determines that it is no longer clinically significant, or the subject is lost to follow up. Further 
details regarding follow up of PDILI events is provided in Section 9.7.1.4.
Information on SAEs obtained after clinical database lock will be captured through the PS
database without limitation of time.
9.3
Immediate reporting of AEs
The following AEs must be reported immediately:

SAE: AE that the Investigator classifies as serious by the definitions in Section 9.2.1
regardless of causality

Suspected transmission of an infectious agent via a medicinal product

AEs of special interest as defined in Section 9.5
9.4
Anticipated SAEs
The following Anticipated SAEs (Table 9‒1) are anticipated to occur in the population studied in 
this protocol at some frequency that is independent of drug exposure. This original list will 
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remain in effect for the duration of the protocol. Note that listed events will not be regarded as 
anticipated SAEs if they are life-threatening or if they result in the death of the study subject.
This list does not change the Investigator’s obligation to report all SAEs (including Anticipated 
SAEs) as detailed in Section 9.2.2.
Table 9‒1:
Anticipated SAEs for the population of subjects with moderate to 
severe chronic plaque psoriasis
MedDRA® system order class
MedDRA preferred term
Skin and subcutaneous tissue disorders
Any psoriatic condition HLT
Musculoskeletal and connective tissue disorders
Psoriatic arthropathy
HLT=high level term; MedDRA=Medical Dictionary for Regulatory Activities; SAE=serious adverse event
Note: Exception: Listed events will not be regarded as anticipated SAEs if they are life-threatening or if they result 
in the death of the study subject.
9.5
Adverse events of special interest
An AE of special interest is any AE that a regulatory authority has mandated be reported on an 
expedited basis, regardless of the seriousness, expectedness, or relatedness of the AE to the 
administration of a UCB product/compound.
Potential Hy’s Law, defined as ≥3xULN ALT or AST with coexisting ≥2xULN total bilirubin in 
the absence of ≥2xULN ALP, with no alternative explanation for the biochemical abnormality, 
must ALWAYS be reported to UCB as an AE of special interest (ie, without waiting for any 
additional etiologic investigations to have been concluded). Follow-up information should then 
be reported if an alternative etiology is identified during investigation and monitoring of the 
subject.
9.6
Adverse events for special monitoring
UCB has identified AEs for special monitoring (AESM). An AESM is an AE or safety topic for 
which special monitoring, additional data collection activities, and/or enhanced signal detection 
activities (within UCB), are considered appropriate. Identified AESM can be of particular 
interest based on findings from the IMP clinical program to date, potential risks generally 
associated with biologic immunomodulators, or comorbidities and risk factors prevalent in the 
study population.
Adverse events for special monitoring for this study include: serious infections (including 
opportunistic infections and TB; see Section 9.8.1), cytopenias, hypersensitivities, suicide 
ideation or behavior (assessed using the C-SSRS; see Section 9.8.6), depression and anxiety 
(assessed using the HADS; see Section 12.4), major cardiovascular events, and liver function test 
changes/enzyme elevations (ALT, AST, bilirubin; see Section 9.7.1), malignancies, and 
inflammatory bowel diseases.
9.7
Laboratory measurements
Clinical laboratory assessments consist of serum chemistry, hematology, and urinalysis. A 
centralized laboratory will be used to supply all laboratory test supplies and analyze all blood 
and urine samples for hematology, biochemistry, and urinalysis measurements. Any unscheduled 
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laboratory testing should also be collected using the central laboratory. Laboratory parameters to 
be measured are listed in Table 9‒2. 
Specific details regarding the handling and processing of serum chemistry, hematology, and 
urinalysis samples are provided in the study laboratory manuals.
Table 9‒2:
Laboratory measurements
Hematology
Chemistry
Urinalysis
Basophils
Calcium
Albumin
Eosinophils
Chloride
Bacteria
Lymphocytes
CRP
Crystals
Atypical lymphocytes
Magnesium
Glucose
Monocytes
Potassium
pH
Neutrophils
Sodium
RBC
Hematocrit
Glucose
WBC
Hemoglobin
BUN
Urine dipstick for pregnancy testinga
MCH
Creatinine
MCHC
ALP
MCV
AST
Platelet count
ALT
RBC count
GGT
WBC count
Total bilirubin
LDH
Total cholesterol
Serum pregnancy testing a
Serum FSHb (Screening)
ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BUN=blood urea 
nitrogen; CRP=C-reactive protein; FSH=follicle stimulating hormone; GGT=gamma glutamyltransferase; 
LDH=lactate dehydrogenase; MCH=mean corpuscular hemoglobin; MCHC=mean corpuscular hemoglobin 
concentration; MCV=mean corpuscular volume; RBC=red blood cell; WBC=white blood cell
a Pregnancy testing will consist of serum testing at the SFU Visit. The pregnancy test will be urine at all other visits 
and will be performed locally.
b The FSH test should only be performed on postmenopausal females who have been postmenopausal for ≥1 year 
and last menstrual cycle occurred <2 year sago.
Assessments of PK variables are described in Section 10. Assessments of immunological
variables are described in Section 11.
9.7.1
Evaluation of PDILI
The PDILI IMP discontinuation criteria for this study are provided in Section 6.3.1, with the 
accompanying required follow-up investigation and monitoring detailed below. All PDILI events 
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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 9.5), and, if applicable, also reported as an SAE 
(see Section 9.2.1). 
Evaluation of PDILI consists of the diagnostic testing and continued monitoring included in 
Table 9-3 (specific tests dependent on laboratory results and corresponding symptoms) and 
consultation with a local hepatologist (if applicable; discussed in Section 9.7.1.1). The local 
hepatologist is the expert usually consulted by the treating physician for assessment and 
management of potential hepatic disease. This would usually be a hepatologist, but may be a 
gastroenterologist. Additional investigation and monitoring may be required and adapted based 
on the diagnosis after the cause of the liver injury/abnormality is confirmed (details in 
Section 9.7.1.4). 
The results of all monitoring, including laboratory testing and other testing, should be made 
available to the study site and Sponsor.
All initial tests resulting in abnormal hepatic laboratory values need to be repeated, but 
appropriate medical action must not be delayed waiting for the repeat result.
If tests are done locally for more rapid results, a concurrent sample should also be sent to the 
central laboratory whenever possible. Medical care decisions are to be made initially using the 
most rapidly available results and a conservative approach must be taken if the results from the 
2 laboratory tests are significantly different. Data from the local and central laboratory are to be 
recorded on the applicable eCRF pages.
When IMP is discontinued, all concomitant medications and herbal supplements that are not 
medically necessary should also be discontinued. In these cases, the Investigator should also 
consider dose reduction for medically necessary concomitant medication and consider changing 
any medically required concomitant medication known to be hepatotoxic to a suitable 
alternative.
When IMP is stopped due to PDILI (as described in Section 6.3.1), IMP must be permanently 
discontinued even if a subsequent alternative diagnosis fully explains the hepatic findings. 
Rechallenge with a substance potentially causing drug-induced liver injury is dangerous, may be 
fatal, and must not occur.
Table 9-3 summarizes the approach to investigate PDILI.
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Table 9-3:
Required investigations and follow-up for PDILI
Laboratory value
Symptoms a of 
hepatitis or 
hypersensitivity
Immediate
Follow up
ALT or 
AST
Total 
bilirubin
Consultation 
requirements
Actions
Testing
Evaluation
≥3xULN
≥2xULN b
NA
Hepatology consult.c
Medical Monitor 
must be notified 
within 24 hours 
(eg, by laboratory 
alert) and subject 
discussed with 
Medical Monitor 
ASAP.
Immediate, permanent 
IMP discontinuation.
Essential: Must 
have repeat liver 
chemistry values 
and additional 
testing completed 
ASAP (see 
Section 9.7.1.3); 
recommended to 
occur at the site 
with HCP.
Monitoring of liver 
chemistry values at least 
twice per week until values 
normalize, stabilize, or 
return to within baseline 
values. d
≥3xULN
NA
Yes
≥5xULN
NA
NA
Need for hepatology 
consult to be 
discussed (required if 
ALT or AST 
≥8xULN).
Medical Monitor 
must be notified 
within 24 hours 
(eg, by laboratory 
alert) and subject 
discussed with 
Medical Monitor 
ASAP.
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Table 9-3:
Required investigations and follow-up for PDILI
Laboratory value
Symptoms a of 
hepatitis or 
hypersensitivity
Immediate
Follow up
ALT or 
AST
Total 
bilirubin
Consultation 
requirements
Actions
Testing
Evaluation
≥3xULN 
(and ≥2x 
baseline) 
and 
<5xULN
(and ≥2x 
baseline)
<2xULN
No
Discussion with 
Medical Monitor 
required.
Consider need for 
hepatology consult if 
there is no evidence 
of resolution (see 
Follow up 
requirements). c
Further investigation –
immediate IMP 
discontinuation not 
required (see 
Section 9.7.1.2).
IMP discontinuation 
required if any of the 
following occur:
Subject cannot comply 
with monitoring 
schedule.
Liver chemistry values 
continue to increase.
Liver chemistry values 
remain ≥3xULN (and 
≥2x baseline) after 
2 weeks of monitoring 
without evidence of 
resolution.
Essential: Every 
attempt must be 
made to have 
repeat liver 
chemistry values 
and additional 
testing completed 
within 48 hours at 
the site with HCP 
(see 
Section 9.7.1.3).
Monitoring of liver 
chemistry values at least 
twice per week for 
2 weeks. d
Immediate IMP 
discontinuation required if 
liver chemistry values 
continue to increase.
After 2 weeks of 
monitoring liver chemistry 
values:
Discontinue IMP if levels 
remain ≥3xULN (and 
≥2x baseline) without 
evidence of resolution d
Continue to monitor until 
values normalize, 
stabilize, or return to 
within baseline values. d
ALT=alanine aminotransferase; ASAP=as soon as possible; AST=aspartate aminotransferase; HCP=healthcare practitioner; IMP=investigational medicinal 
product; NA=not applicable; PDILI=potential drug-induced liver injury; ULN=upper limit of normal 
a Hepatitis symptoms include fatigue, nausea, vomiting, and right upper quadrant pain or tenderness; hypersensitivity symptoms include eosinophilia (>5%), 
rash, and fever (without clear alternative cause).
b If the subject also has ≥2xULN alkaline phosphatase, the possibility of an indication of biliary obstruction should be discussed with the Medical Monitor.
.c Details provided in Section 9.7.1.1. The local hepatologist is the expert usually consulted by the treating physician for assessment and management of potential 
hepatic disease. This would usually be a hepatologist, but may be a gastroenterologist.
d Unless an alternative monitoring schedule is agreed by the Investigator and UCB responsible physician. Determination of stabilization is at the discretion of the 
Investigator in consultation with the hepatologist (as applicable) and UCB responsible physician, as needed.
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9.7.1.1
Consultation with Medical Monitor and local hepatologist 
Potential drug-induced liver injury events require notification of the Medical Monitor within 
24 hours (eg, by laboratory alert), and the subject must be discussed with the Medical Monitor as 
soon as possible. If required, the subject must also be discussed with the local hepatologist. The 
local hepatologist is the expert usually consulted by the treating physician for assessment and 
management of potential hepatic disease. This would usually be a hepatologist, but may be a 
gastroenterologist. If determined necessary, this discussion should be followed by a full 
hepatology assessment (see Section 9.7.1.3) and SAE report (if applicable).
9.7.1.2
Immediate action: determination of IMP discontinuation
All PDILI events require immediate action, testing, and monitoring. 
The immediate action is dependent on the laboratory values and symptoms of hepatitis or 
hypersensitivity and ranges from continuation of IMP (followed by immediate investigation) to 
immediate and permanent discontinuation (see Section 6.3.1 and Table 9-3 for details).
When IMP is discontinued, all concomitant medications and herbal supplements that are not 
medically necessary should also be discontinued. The Investigator should also consider dose 
reduction for medically necessary concomitant medication and consider changing any medically 
required concomitant medication known to be hepatotoxic to a suitable alternative.
9.7.1.3
Testing: identification/exclusion of alternative etiology
The measurements and additional information required for the assessment of PDILI events when 
there is a reasonable possibility that they may have been caused by the IMP include, but are not 
limited to, those listed in Table 9-4 (laboratory measurements) and Table 9-5 (additional 
information). Results of the laboratory measurements and information collected are to be 
submitted to the Sponsor on the corresponding eCRF. If the medical history of the subject 
indicates a requirement for other assessments not included below, these additional assessments 
should be completed and submitted, as applicable.
All blood samples should be stored, if possible. If tests are done locally for more rapid results, a 
concurrent sample must also be sent to the central laboratory.
The laboratory measurements to be assessed are presented in Table 9-4.
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Table 9-4:
PDILI laboratory measurements
Virology-
related
Hepatitis A IgM antibody
HBsAg
Hepatitis E IgM antibody
HBcAb-IgM
Hepatitis C RNA
Cytomegalovirus IgM antibody
Epstein-Barr viral capsid antigen IgM antibody (if unavailable, obtain 
heterophile antibody or monospot testing)
Immunology
Anti-nuclear antibody (qualitative and quantitative)
Anti-smooth muscle antibody (qualitative and quantitative)
Type 1 anti-liver kidney microsomal antibodies (qualitative and/or quantitative)
Hematology
Eosinophil count
Urinalysis
Toxicology screena
Chemistry
Amylase
If total bilirubin ≥1.5xULN, obtain fractionated bilirubin to obtain % direct 
bilirubin
Serum CPK and LDH to evaluate possible muscle injury causing transaminase 
elevation
Additional
Prothrombin time/INRb
Serum pregnancy test
PK sample
ALT=alanine aminotransferase; CPK=creatine phosphokinase; HBcAb-IgM=hepatitis B core antibody-IgM; 
HBsAg=hepatitis B surface antigen; IgM=immunoglobulin M; INR=international normalized ratio; LDH=lactate 
dehydrogenase; PDILI=potential drug-induced liver injury; PK=pharmacokinetic; RNA=ribonucleic acid; 
ULN=upper limit of normal
a For detecting substances (ie, amphetamines, benzodiazepines, opioids, marijuana, cocaine, phencyclidine, and 
tricyclic antidepressants), additional tests may be performed based on the Investigator’s medical judgment and 
patient’s history.
b Measured only for subjects with ALT >8xULN, elevations in total bilirubin, and symptoms of hepatitis or 
hypersensitivity. Hepatitis symptoms include fatigue, nausea, vomiting, and right upper quadrant pain or 
tenderness; hypersensitivity symptoms include eosinophilia (>5%), rash, and fever (without clear alternative 
cause).
Additional information to be collected is presented in Table 9-5.
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Table 9-5:
PDILI information to be collected
New or updated information
Concomitant prescription and over-the-counter medications (eg, acetaminophen, herbal remedies, 
vitamins); dosages and dates should be included.
Pertinent medical history, including the following:

History of liver disease (eg, autoimmune hepatitis, nonalcoholic steatohepatitis or other “fatty liver 
disease”)

Adverse reactions to drugs

Allergies

Relevant family history or inheritable disorders (eg, Gilbert’s syndrome, alpha-1 antitrypsin 
deficiency)

Recent travel 

Progression of malignancy involving the liver (Note: Metastatic disease to the liver, by itself, should 
not be used as an explanation for significant AST and/or ALT elevations.)
The appearance or worsening of clinical symptoms of hepatitis or hypersensitivity (eg, fatigue, nausea, 
vomiting, right upper quadrant pain or tenderness, decreased appetite, abdominal pain, jaundice, fever, or 
rash)
Recent clinically significant hypotension or hypoxemia with compromised cardiopulmonary function
Alcohol and illicit drug use
Results of liver imaging or liver biopsy, if done
Results of any specialist or hepatology consult, if done
Any postmortem/pathology reports
ALT=alanine aminotransferase; AST=aspartate aminotransferase; PDILI=potential drug-induced liver injury
9.7.1.4
Follow-up evaluation
Potential drug-induced liver injury events require follow-up monitoring as described in 
Table 9-3. Monitoring should continue until liver chemistry values normalize, stabilize, or return 
to baseline. Determination of stabilization is at the discretion of the Investigator in consultation 
with the hepatologist (as applicable) and UCB responsible physician, as needed.
9.8
Other safety measurements
9.8.1
Assessment and management of TB and TB risk factors
All subjects will be assessed for TB through physical examination for signs and symptoms of 
TB, laboratory testing (Section 9.8.1.1), and subject questionnaire (Section 9.8.1.3). A chest 
x-ray can be performed in PS0018, if warranted, to confirm or exclude TB (Section 9.8.1.2).
At the Baseline Visit of PS0018, all subjects will undergo physical examination for signs and 
symptoms of TB and must be confirmed to have undergone an IGRA test (QuantiFERON TB 
GOLD is recommended) in PS0016 with negative results. In addition, each subject will complete 
a TB questionnaire with questions directed at symptoms of TB and potential exposure to TB. 
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Exclusion criteria at Baseline of PS0018
Subjects with known TB infection, at high risk of acquiring TB infection, or latent TB infection 
are excluded. 
a.
Known TB infection whether present or past is defined as:

Active TB infection or clinical signs and symptoms suspicious for TB (pulmonary or 
extra-pulmonary)

History of active TB infection involving any organ system or findings in other organ 
systems consistent with TB infection, unless adequately treated and proven to be fully 
recovered upon consult with a TB specialist

Any evidence by radiography or other imaging modalities consistent with previously 
active TB infection that is not reported in the subject’s medical history
b. High risk of acquiring TB infection is defined as:

Known exposure to another person with active TB infection within the 3 months prior to 
enrollment

Time spent in a healthcare delivery setting or institution where individuals infected with
TB are housed and where the risk of transmission of infection is high
c.
Latent TB infection is defined as:

The absence of signs, symptoms (ie, evidence of organ-specific involvement), or physical 
findings suggestive of TB infection with a positive IGRA test (or 2 indeterminate IGRA 
test results) and a chest x-ray (or other imaging) without evidence of TB infection. If the 
result of the IGRA test is indeterminate, the particular IGRA test previously performed 
may be repeated once; if positive or indeterminate on retest, the subject may not be 
enrolled in the study. The retest must be done prior to entry in PS0018.
Note: If available, respiratory or other specimens must also be smear and culture 
negative for TB (Centers for Disease Control diagnosis of LTB infection 
http://www.cdc.gov/TB/topic /testing/default.htm)
d. Current or history of NTMB infection
Signs and Symptoms
The Investigator should consider all potential sites of infection when assessing for TB during the 
physical examination and other evaluations, and based on the subject’s medical or social history. 
The most common primary focus of TB is the lung. Other sites may include GI system, 
bone/joints, lymph glands and meninges, etc. However, in immune compromised patients and/or 
patients treated with TNF inhibitors, extrapulmonary manifestations of TB are common 
compared to the normal population.
Some common symptoms that the subject 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 inflammatory 
bowel disease), etc. Unusual presentations should always be considered.
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Latent TB infection is defined in the “Exclusion Criteria” above. If the result of the IGRA is 
indeterminate, the particular IGRA previously performed may be repeated once; if positive or 
indeterminate on retest, the subject may not be enrolled in the study without further evaluation 
by a TB specialist. In the event of an indeterminate test result, the retest must be done prior to the 
next visit. If LTB infection or active TB is identified, subject must undergo appropriate study 
specified withdrawal procedures. Laboratory diagnosis should be undertaken via mycobacteria 
culture media (or if available by preferred nucleic acid amplification test such as the Xpert MTB 
RIF test) and the result must be negative for TB inducing pathogens.
Test Conversion
Tuberculosis test conversion is defined as a positive IGRA result for the current test when 
previous IGRA test results were negative. All subjects with TB test conversion must immediately 
stop study drug administration. In case of a TB test conversion, the subject 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. If 
test conversion indicates LTB infection, active TB, or NTMB then, per UCB TB working 
instructions, TB test conversion (confirmed) should be classified adequately, either as due to 
LTB infection, active TB infection, or NTMB, respectively. 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 to the UCB PS function.
LTB
In case the evaluation by the appropriate specialist indicates a new LTB infection during the 
study, a prophylactic TB treatment should be initiated and the subject must be withdrawn from 
the study. Every related action should be discussed in advance with the Medical Monitor. 
Once withdrawn from study treatment, subjects should return for the Week 48/Withdrawal Visit, 
complete all Early Withdrawal Visit assessments, and complete a SFU Visit (20 weeks after the 
last dose of study medication).
Active TB or NTMB infection 
Subjects who develop active TB or NTMB infection during the study must be withdrawn from 
the study. The subject must be immediately discontinued from study medication and an Early 
Withdrawal Visit must be scheduled as soon as possible, but no later than the next scheduled 
visit. The subject should be encouraged to keep the SFU Visit as specified by the protocol. 
Treatment should be started immediately.
Note that subjects with history of NTMB or active NTMB infection are excluded from the study 
regardless of prior or current therapy for this condition. 
9.8.1.1
TB assessment by IGRA
During conduct of the study, the TB assessment by IGRA (QuantiFERON TB GOLD is 
recommended) will be performed at the final visit of PS0016 and should be repeated at 
Week 48/Early Withdrawal Visit and the SFU visit for all subjects. The test results will be 
reported as positive, negative, or indeterminate. UCB also recommends that a TB specialist be 
consulted where TB (latent or active) is suspected or if there are doubts regarding test results. If 
latent or active TB is identified, the subject must undergo appropriate study-specified withdrawal 
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procedures. In the event of an indeterminate test result, the retest must be done prior to the next 
visit.
9.8.1.2
Chest x-ray for TB
Chest x-ray will be performed in PS0018 only when required to confirm or exclude TB. Any 
new clinically significant findings on chest x-ray must be documented in the source documents 
and the eCRF as an AE.
9.8.1.3
TB questionnaire 
The questionnaire “Evaluation of signs and symptoms of tuberculosis” should be used as a 
source document. The questionnaire will be completed at the Baseline Visit of PS0018, and at 
the Week 12, Week 24, Week 36, and Week 48/Withdrawal Visit. The questionnaire will assist 
with the identification of subjects who may require therapy for TB. A subject who answers 
“Yes” to the question
 
 or to any of the other questions within 
the questionnaire at any visit should trigger further careful assessment to determine if subject has 
LTB or active TB. 
Subjects with a latent or active TB infection must be withdrawn from the study.
9.8.1.4
TB management
LTB infection and active TB identified during study
During the study, subjects who develop evidence of LTB infection or active TB must 
immediately stop further administration of study medication and will be referred to an 
appropriate TB specialist (pulmonologist or infectious disease specialist) for further evaluation. 
Evidence of LTB infection is defined as the subject’s IGRA test converts to positive or 
indeterminate (and confirmed indeterminate on repeat), or the subject’s questionnaire or history 
and physical indicates that TB infection or exposure may have occurred. Evidence of active TB 
includes, in addition to the aforementioned tests, signs and symptoms of organ involvement. In 
either situation, the subject should be carefully assessed by a TB specialist for active TB. 
Subjects diagnosed with active TB or LTB infection should be withdrawn from the study and 
receive appropriate TB or prophylaxis therapy. 
Any presumptive diagnosis or diagnosis of a TB infection is a reportable event. Confirmed active 
TB must be reported as an SAE. The Investigator is to complete and submit the TB follow up 
form provided.
The subject should be transferred to the care of his/her physician and managed according to the 
best available standard of care. Subjects identified as having converted to active TB during the 
study must be withdrawn and scheduled to return for the Week 48/Withdrawal Visit as soon as 
possible, but no later than the next scheduled study visit, and complete all Week 48/Withdrawal 
Visit assessments. 
The subject should be encouraged to complete a SFU Visit (20 weeks after the last dose of study 
medication).
If infection with NTMB is identified during the study, the same procedure as for active TB 
acquired during the study must be followed.
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9.8.2
Pregnancy testing
Pregnancy testing will consist of serum testing at the SFU Visit and urine testing at all other 
visits. 
The Baseline Visit urine pregnancy test result must be negative prior to enrollment of the subject. 
A negative urine pregnancy test result should be obtained immediately prior to each 
administration of study drug and at all subsequent visits. Pregnancy tests should be administered 
to all female subjects of childbearing potential, regardless of their use of birth control.
9.8.3
Vital signs
Vital signs will be collected at every visit and will include systolic and diastolic blood pressure, 
pulse rate, and body temperature (oral, axillary, or otic). Subjects should be sitting for 5 minutes 
before and during vital signs assessments. 
Vital signs are to be measured prior to blood sampling, and prior to dosing, where applicable. 
Body weight will be measured at the time points specified in the schedule of study assessments 
(Table 5‒1).
9.8.4
12-lead ECGs
Standard 12-lead ECG will be recorded after 10 minutes of rest in the supine or semirecumbent 
position. The following ECG variables will be recorded: heart rate, PR interval, QRS duration, 
QT interval, Fridericia’s  QTc interval (QTcF), and the Investigator’s interpretation of the ECG 
profile.
9.8.5
Physical examination
The physical examination will include general appearance; ear, nose, and throat; eyes, hair, and 
skin; respiratory; cardiovascular; GI; musculoskeletal; hepatic; neurological (including limb 
reflexes); and mental status. Physical examination will be performed at the time points specified 
in the schedule of study assessments (Table 5‒1). Findings considered clinically significant 
changes since the physical examination at the Screening Visit of PS0016 will be recorded as 
AEs.
9.8.6
Assessment of suicidal ideation and behavior
Suicidal ideation and behavior will be assessed by trained study personnel using the C-SSRS. 
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 schedule of 
study assessments (Table 5‒1).
The C-SSRS is a standardized and validated instrument developed for the assessment of the 
severity and frequency of suicidal ideation and behavior (Mundt et al, 2010; Posner et al, 2011). 
Subjects respond to standardized clinical questions that are presented in a uniform fashion. The 
C-SSRS defines five 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 6.3 for C-SSRS-related withdrawal criteria.
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9.8.7
Data Monitoring Committee
The DMC membership includes clinicians knowledgeable about the disease or the treatment. The 
DMC will include a statistician, and at a minimum, specialists in dermatology and infectious 
disease. All members have experience and expertise in clinical trials. Board members may not 
participate in the study as principal or co-Investigators, or as study subject care physicians. The 
duration of membership for the DMC will be inclusive of planned analyses for PS0018. The 
DMC may also be asked to provide a review of final study results, as deemed appropriate.
The detailed role, scope, responsibilities, and complete procedures, as well as the identity of the 
DMC members, will be described in a separate charter document.
The DMC procedures will ensure that data remain blind to the study team and Investigators at all 
times throughout the conduct of the study.
A Cardiovascular Adjudication Committee will also periodically review the safety data from this 
study. Details will be described in a separate charter document.
10
ASSESSMENT OF PHARMACOKINETIC VARIABLES
Blood samples for measurement of PK (Section 4.2) will be collected at the time points specified 
in the schedule of study assessments (Table 5‒1). 
At dosing visits, blood samples will be drawn prior to dosing, and will be drawn at the same time 
of the sampling for clinical laboratory tests. The time and date of collection will be recorded in 
the eCRF. 
Instructions pertaining to sample collection, processing, storage, labeling, and shipping are 
provided in the laboratory manual for this study. Detailed information on sample analysis will be 
provided in a bioanalytical report.
11
ASSESSMENT OF IMMUNOLOGICAL VARIABLES
Blood samples for measurement of antibodies to bimekizumab will be collected at the visits 
specified in Table 5‒1. The threshold for antibody positivity will be defined prior to analysis.
At dosing visits, blood samples will be drawn prior to dosing, and will be drawn at the same time 
of the sampling for clinical laboratory tests. The time and date of collection will be recorded in 
the eCRF. 
Instructions pertaining to sample collection, processing, storage, labeling, and shipping are 
provided in the laboratory manual for this study. The presence of antibodies to bimekizumab will 
be determined using a validated bioanalytical method. Detailed information on sample analysis 
will be provided in a bioanalytical report.
12
ASSESSMENT OF EFFICACY
12.1
Psoriasis Area and Severity Index
The PASI is the most commonly used and validated assessment for grading the severity of 
psoriasis in clinical studies (Feldman, 2004). The PASI quantifies the severity and extent of the 
disease and weighs these with the percentage of BSA involvement. 
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The degree of involvement is estimated across 4 body areas; head, upper limbs, trunk, and lower 
limbs and then transferred into a grade (Table 12‒1). 
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 12‒1: Body areas for calculation of percent BSA for PASI
Body area
Details of area
BSA
Degree of involvement of 
body area a
Head
Face, back of head
10% 
0 to 6
Upper limbs 
Left, right, upper lower, flexor surface, 
extensor surface
20% 
0 to 6
Trunk
Front, back, groin
30% 
0 to 6
Lower limbs 
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. The improvement will be based on changes from the 
PASI score at the Baseline of PS0016.
The PASI will be completed at the visits specified in Table 5‒1.
12.2
Investigator’s Global Assessment
A static IGA for psoriasis will be used to assess disease severity in all subjects during the study. 
The IGA will be completed at the visits specified in Table 5‒1. 
The Investigator will assess the overall severity of psoriasis using the following 5-point scale:
5 point Investigator’s Global Assessment
Score
Short Descriptor
Detailed Descriptor
0
Clear
No signs of psoriasis; post-inflammatory hyperpigmentation may be 
present
1
Almost clear
No thickening; normal to pink coloration; no to minimal focal scaling
2
Mild
Just detectable to mild thickening; pink to light red coloration; 
predominately fine scaling
3
Moderate
Clearly distinguishable to moderate thickening; dull to bright red, 
clearly distinguishable to moderate thickening; moderate scaling
4
Severe
Severe thickening with hard edges; bright to deep dark red coloration; 
severe/coarse scaling covering almost all or all lesions
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12.3
BSA affected by psoriasis
The BSA palm method will be used for the evaluation of BSA as follows:
Body surface area estimation uses the palm (subject’s flat hand and thumb together, fingers 
included) as representing around 1% of the total BSA.

Subject’s palm=1%

Head and neck=10% (10 palms)

Upper extremities=20% (20 palms)

Trunk=30% (30 palms)

Lower extremities=40% (40 palms) 

Total BSA=100%
Evaluation of BSA will be completed at the visits specified in Table 5‒1.
12.4
Hospital Anxiety and Depression Scale
The HADS was chosen for its well-established psychometric properties and its use in clinical 
research on biological therapy in subjects with chronic plaque psoriasis (Dauden et al, 2009; 
Langley et al, 2010). The HADS scores for anxiety and for depression range from 0 to 21 with 
higher scores indicating worse state. A score below 8 is considered to be normal 
(Snaith and Zigmond, 1994).
13
STUDY MANAGEMENT AND ADMINISTRATION 
13.1
Adherence to protocol
The Investigator should not deviate from the protocol. However, the Investigator should take any 
measure necessary in deviation from or not defined by the protocol in order to protect clinical 
study subjects from any immediate hazard to their health and safety. In this case, this action 
should be taken immediately, without prior notification of the regulatory authority, IRB/IEC, or 
Sponsor.
After implementation of such measure, the Investigator must notify the Clinical Project Manager 
of the Sponsor within 24 hours and follow any local regulatory requirements.
13.2
Monitoring
The CRO will monitor the study using their own monitoring Standard Operating Procedures
(SOPs), in line with ICH GCP guidelines and applicable regulatory requirements, and to ensure 
that study initiation, conduct, and closure are adequate.
The Investigator and his/her staff are expected to cooperate with UCB (or designee) and to be 
available during the monitoring visits to answer questions sufficiently and to provide any 
missing information. The Investigator(s)/institution(s) will permit direct access to source 
data/documents for study-related monitoring, audits, IRB/IEC review, and regulatory 
inspection(s).
The Investigator will allow UCB (or designee) to periodically review all eCRFs and 
corresponding source documents (eg, hospital and laboratory records for each study participant). 
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Monitoring visits will provide UCB (or designee) with the opportunity to evaluate the progress 
of the study, verify the accuracy and completeness of eCRFs, ensure that all protocol 
requirements, applicable authorities regulations, and Investigator’s obligations are being 
fulfilled, and resolve any inconsistencies in the study records.
13.2.1
Definition of source data 
All source documents must be accurate, clear, unambiguous, permanent, and capable of being 
audited. Source documentation should be made using some permanent form of recording (ink, 
typing, printing, optical disc). They should not be obscured by correction fluid or have temporary 
attachments (such as removable self-stick notes). Photocopies 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, or QOL questionnaires, for example. Source documents should be kept in a secure, 
limited access area.
The Sponsor or designee will review to ensure that computerized source documents produced by 
the site are compliant with Food and Drug Administration (FDA) Part 11 requirements and 
document appropriately. Source documents that are computer generated and stored electronically 
that are not FDA Part 11 compliant, must be printed for review by the monitor (eg, ECG reports). 
Once printed, these copies should be signed and dated by the Investigator and become a 
permanent part of the subject’s source documents. The Investigator will facilitate the process for 
enabling the monitor to compare the content of the printout and the data stored in the computer 
to ensure all data are consistent.
Electronic data records, such as PASI data, must be saved and stored as instructed by the 
Sponsor or designee. 
13.2.2
Source data verification
Source data verification ensures accuracy and credibility of the data obtained. During monitoring 
visits, reported data are reviewed with regard to being accurate, complete, and verifiable from 
source documents (eg, subject files, recordings from automated instruments, tracings [ECG], 
x-ray films, laboratory notes). All data reported on the eCRF should be supported by source 
documents, unless otherwise specified in Section 13.2.1.
13.3
Data handling
13.3.1
eCRF completion
This study will use electronic data capture (EDC); the Investigator is responsible for prompt 
reporting of accurate, complete, and legible data in the eCRF and in all required reports.
Serious AE reporting will be done using the SAE Form (see Section 9.2.2) while also entering 
the event in the appropriate eCRF section. The safety database and the clinical database will be 
reconciled during the study and discrepancies will be corrected as needed.
The Investigator should maintain a list of personnel authorized to enter data into the eCRF. 
Access to the EDC will be given after training has been received. A training certificate will be 
provided and filed.
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Detailed instructions on the use of the EDC will be provided in the eCRF Completion 
Guidelines.
Corrections made after the Investigator’s review and approval (by means of a 
password/electronic signature) will be re-approved by the Investigator. Any change or correction 
to the eCRF after saving must be accompanied by a reason for the change.
13.3.2
Database entry and reconciliation
Case Report Forms/external electronic data will be entered/loaded into a validated electronic 
database using a clinical data management system. Computerized data cleaning checks will be 
used in addition to manual review to check for discrepancies and to ensure consistency of the 
data. This study is performed using EDC: the data are entered into the eCRFs once and are 
subsequently verified.
An electronic audit trail system will be maintained to track all data changes in the database once 
the data have been saved initially into the system or electronically loaded. Regular backups of 
the electronic data will be performed.
13.3.3
Subject Screening and Enrollment log/Subject Identification Code list
The subject’s screening and enrollment will be recorded in the Subject Enrollment Log.
The Investigator will keep a Subject Identification Code list. This list remains with the 
Investigator and is used for unambiguous identification of each subject.
The subject’s consent and enrollment in the study must be recorded in the subject’s medical 
record. These data should identify the study and document the dates of the subject’s 
participation.
13.4
Termination of the study
UCB reserves the right to temporarily suspend or prematurely discontinue this study either at a 
single site, multiple sites, or at all sites at any time for reasons including, but not limited to, 
safety or ethical issues, inaccurate or incomplete data recording, noncompliance, or 
unsatisfactory enrollment with respect to quality or quantity.
If the study is prematurely terminated or suspended, UCB (or its representative) will inform the 
Investigators/institutions and the regulatory authority(ies) of the termination or suspension and 
the reason(s) for the termination or suspension, in accordance with applicable regulatory 
requirement(s). The IRB/IEC should also be informed and provided with reason(s) for the 
termination or suspension by the Sponsor or by the Investigator/institution, as specified by the 
applicable regulatory requirement(s). In addition, arrangements will be made for the return of all 
unused IMP and other material in accordance with UCB procedures for the study.
13.5
Archiving and data retention
The Investigator will maintain adequate records for the study, including eCRFs, medical records, 
laboratory results, Informed Consent documents, drug dispensing and disposition records, safety 
reports, information regarding participants who discontinued, and other pertinent data.
All essential documents are to be retained by the Investigator until at least 2 years after the last 
approval of a marketing application in an ICH region and until there are no pending or 
contemplated marketing applications in an ICH region, or at least 2 years have elapsed since the 
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formal discontinuation of clinical development of the IMP. These documents should be retained 
for a longer period, however, if required by the applicable regulatory requirement(s) or by an 
agreement with UCB (Committee for Proprietary Medicinal Products [CPMP]/ICH/135/95, 2002 
[Section 4.9.5]). The Investigator will contact UCB for authorization prior to the destruction of 
any study records or in the event of accidental loss or destruction of any study records. The 
Investigator will also notify UCB should he/she relocate or move the study-related files to a 
location other than that specified in the Sponsor’s study master file.
13.6
Audit and inspection
The Investigator will permit study-related audits mandated by UCB, after reasonable notice, and 
inspections by domestic or foreign regulatory authorities.
The main purposes of an audit or inspection are to confirm that the rights and well-being of the 
subjects enrolled have been protected, that enrolled subjects (ie, signing consent and undergoing 
study procedures) are appropriate for the study, and that all data relevant for the evaluation of the 
IMP have been processed and reported in compliance with the planned arrangements, the 
protocol, investigational site, and IRB/IEC SOPs, ICH GCP, and applicable regulatory 
requirements.
The Investigator will provide direct access to all study documents, source records, and source 
data. If an inspection by a regulatory authority is announced, the Investigator will immediately 
inform UCB (or designee).
13.7
Good Clinical Practices
Noncompliance with the protocol, ICH-GCP, or local regulatory requirements by the 
Investigator, institution, institution staff, or designees of the Sponsor will lead to prompt action 
by UCB to secure compliance. Continued noncompliance may result in the termination of the 
site’s involvement in the study.
14
STATISTICS
A description of statistical methods is presented below and will be described in more detail in the 
Statistical Analysis Plan (SAP).
14.1
Definition of analysis sets
The Enrolled Set (ES) will consist of all subjects who have given informed consent for PS0018.
The Safety Set (SS) will consist of all subjects who receive at least 1 dose of the study 
medication in PS0018.
The Full Analysis Set (FAS) will consist of all enrolled subjects who receive at least 1 dose of 
the study medication and have a valid efficacy measurement for PASI at Baseline of PS0018. 
The Pharmacokinetics Per-Protocol Set (PK-PPS) will consist of all enrolled subjects who 
receive at least 1 dose of the study medication and provide at least 1 quantifiable plasma 
concentration postdose in PS0018.
14.2
Planned safety analyses
Safety variables will be analyzed for all subjects in the SS.
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Adverse events will be coded according to the Medical Dictionary for Regulatory Activities 
(MedDRA®). Treatment-emergent AEs will be defined as events that have a start date on or 
following the first administration of study treatment in PS0018 through the final administration 
of study treatment +140 days (covering the 20-week SFU Period). Treatment-emergent AEs will 
be categorized to treatment group based on the dose being received at the time of onset of the 
event. Tables will include columns for bimekizumab 320mg Q4W, bimekizumab 160mg Q4W, 
and All bimekizumab (ie, either dose of bimekizumab). 
Change from Baseline safety variables will be defined relative to the Baseline measurement from 
PS0016.
14.2.1
Primary safety analysis
All TEAEs will be summarized descriptively by treatment group, primary system organ class 
(SOC), high level term (HLT), and preferred term (PT). This summary will include the exposure 
adjusted incidence rate (EAIR) with associated 95% confidence interval and the exposure 
adjusted event rate (EAER). 
For EAIR, the numerator will be the total number of subjects experiencing the AE. The
denominator will be 100 subject-years; that is, the total summation of individual subject-years at 
risk up to the first occurrence of the AE for subjects with that AE, and the total subject-years at 
risk for those subjects not experiencing that AE, divided by 100. Exposure adjusted incidence 
rates will be presented with a 95% exact confidence interval based upon the Chi-Square 
distribution (Ulm, 1990). 
For EAERs, the numerator will be the number of AEs including repeat occurrences in individual 
subjects; the denominator will be 100 subject-years. That is, the total summation of individual 
subject-years at risk divided by 100. No confidence interval will be computed for EAER. 
Subject exposure at risk in days will be defined as date of last administration of study medication 
– date of first administration of study medication +140 days (ie, the duration of the SFU Period). 
If a subject dies, patient exposure at risk is censored at the date of death. The sum of these 
exposure days at risk across subjects is converted to years for the EAIR and EAER calculations 
described above.
14.2.2
Other safety analyses
Additional tables will summarize TEAEs by intensity and relationship to study medication, 
TEAEs leading to withdrawal from the study, treatment-emergent SAEs, and deaths. 
In order to evaluate if there is any difference in the TEAE profile of subjects who have dose 
adjustments, additional summaries will be generated and are described further here. With respect 
to dose adjustments, subjects will be classified into 1 of the following 3 groups:

Nonadjusters – This group consists of subjects who do not experience a dose adjustment 
during the study.

Single adjusters – This group consists of subjects who experience just one dose adjustment 
during the study. Per the protocol, if just a single adjustment occurs, then that adjustment 
must be to go from bimekizumab 160mg Q4W to 320mg Q4W.

Multiple adjusters – This group consists of subjects who experience more than 1 dose 
adjustment during the study. This means that the subjects in this group dose adjust from 
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bimekizumab 160mg Q4W to 320mg Q4W and then adjust back to 160mg Q4W (with 
further dose adjustments possible).
Summaries based on these 3 groups will be done by PS0016 randomized treatment group for the 
TEAE overview, incidence of TEAEs (by SOC, HLT, and PT), and incidence of treatment-
emergent SAEs.
Extent of exposure to study medication in PS0018 will be summarized using descriptive 
statistics. As with the primary summaries of TEAEs, extent of exposure will be presented with 
columns for bimekizumab 160mg Q4W, bimekizumab 320mg Q4W, and All bimekizumab. 
Change from Baseline in laboratory values, ECGs, and vital signs will be presented using 
descriptive statistics by PS0016 randomized treatment group and overall. As these variables are 
summarized over time and the initial values can be impacted by the randomized treatment in 
PS0016, the presentation by PS0016 randomized treatment group is intended to provide 
perspective on the change in these values starting with the initial PS0016 randomization through 
the 48-week Open-Label Treatment Period of PS0018. The table presentations will display 
descriptive statistics for the PS0016 Baseline and the observed and change from PS0016
Baseline results by scheduled visit for PS0018.
14.3
Planned PK analyses
Pharmacokinetic variables will be analyzed for all subjects in the PK-PPS. 
Bimekizumab plasma concentrations will be summarized for each treatment at each scheduled 
visit.
14.4
Planned immunological analyses
Immunological variables will be analyzed for all subjects in the PK-PPS. 
Anti-bimekizumab antibody data will be summarized for each treatment at each scheduled visit.
14.5
Planned efficacy analyses
Efficacy variables will be summarized based on the FAS. The summaries described in this 
section will provide data on maintenance of effect of open-label bimekizumab over 48 weeks. 
Additionally, it will allow an assessment of the impact of dose adjustments on efficacy results.
Responder efficacy variables (PASI50, PASI75, PASI90, PASI100, IGA score of 0 or 1, and 
HADS normal scores) will be summarized descriptively using counts and percentages by 
scheduled visit and PS0016 randomized treatment group and overall. The PASI responder 
variables are derived relative to the PS0016 Baseline. Missing data will be handled by using 
nonresponder imputation (NRI), meaning that subjects that discontinue early or who have 
missing data at a given time point are imputed as though they did not achieve the given response. 
Supportive summaries will be based on observed case data.
Continuous efficacy variables based on the change from Baseline (PASI, BSA, and HADS) will 
be summarized using descriptive statistics by scheduled visit and PS0016 randomized treatment 
group and overall. The table presentations will display descriptive statistics for the PS0016
Baseline and the observed and change from PS0016 Baseline results by scheduled visit for 
PS0018. Figures for selected variables will also be generated in order to demonstrate the kinetics 
of response over time. Missing data will be handled by using multiple imputation (MI) via the 
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Markov-Chain Monte Carlo (MCMC) method. Supportive summaries will be based on observed 
case data.
In addition to the summaries described above, the impact of dose adjustment on efficacy will be 
considered. This will be done primarily by summarizing efficacy variables by the 3 adjuster 
groups as defined in Section 14.2.2. Furthermore, a supportive analysis specifically for single 
adjusters will be performed in which PASI score will be summarized by visit, where Baseline is 
recalibrated for each individual subject and defined as the visit where the bimekizumab 
320mg Q4W dose is initiated. The visits summarized will be in weeks relative to when the 
320mg Q4W dose was started as opposed to the scheduled week of the PS0018 assessment.
These summaries will be based on observed data only.
14.6
Planned interim analysis and data monitoring
A DMC will review the safety data on a recurring basis as outlined in the DMC charter.
14.7
Determination of sample size
Up to 45 subjects are anticipated to enroll in PS0018. This number is based on the fact that 
45 subjects are planned to be randomized in the feeder study, PS0016. The calculations to reach 
that sample size are outlined in the PS0016 protocol. As the primary objective of this study is to 
assess the long-term safety and tolerability of bimekizumab 160mg Q4W, the number of subjects 
anticipated is based on the number of subjects completing PS0016 and meeting eligibility 
requirements for PS0018.
15
ETHICS AND REGULATORY REQUIREMENTS
15.1
Informed consent
Subject’s informed consent must be obtained and documented in accordance with local 
regulations, ICH-GCP requirements, and the ethical principles that have their origin in the 
principles of the Declaration of Helsinki.
Prior to obtaining informed consent, information should be given in a language and at a level of 
complexity understandable to the subject in both oral and written form by the Investigator (or 
designee). Each subject will have the opportunity to discuss the study and its alternatives with 
the Investigator.
Prior to participation in the study, the written Informed Consent Form should be signed and 
personally dated by the subject and by the person who conducted the informed consent 
discussion (Investigator or designee). The subject must receive a copy of the signed and dated 
Informed Consent Form. As part of the consent process, each subject must consent to direct 
access to his/her medical records for study-related monitoring, auditing, IRB/IEC review, and 
regulatory inspection.
If the Informed Consent Form 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 Informed Consent Form by the IRB/IEC and use of the amended form.
All studies conducted at centers in the United States must include the use of a Health Insurance 
Portability and Accountability Act Authorization form.
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The subject may withdraw his/her consent to participate in the study at any time. A subject is 
considered as enrolled in the study when he/she has signed the Informed Consent Form. An 
eCRF must not be started, nor may any study specific procedure be performed for a given 
subject, without having obtained his/her written consent to participate in the study.
15.2
Subject identification cards
Upon signing the Informed Consent, the subject will be provided with a subject identification 
card in the language of the subject. The Investigator will fill in the subject identifying 
information and medical emergency contact information. The Investigator will instruct the 
subject to keep the card with him/her at all times.
15.3
IRBs and IECs
The study will be conducted under the auspices of an IRB/IEC, as defined in local regulations, 
ICH-GCP, and in accordance with the ethical principles that have their origin in the Declaration 
of Helsinki.
The Investigator/UCB will ensure that an appropriately constituted IRB/IEC that complies with 
the requirements of the current ICH-GCP version or applicable country-specific regulations will 
be responsible for the initial and continuing review and approval of the clinical study. Prior to 
initiation of the study, the Investigator/UCB will forward copies of the protocol, Informed 
Consent Form, IB, Investigator’s curriculum vitae (if applicable), advertisement (if applicable), 
and all other subject-related documents to be used for the study to the IRB/IEC for its review and 
approval.
Before initiating a study, the Investigator will have written and dated full approval from the 
responsible IRB/IEC for the protocol.
The Investigator will also promptly report to the IRB/IEC all changes in the study, all 
unanticipated problems involving risks to human subjects or others, and any protocol deviations, 
to eliminate immediate hazards to subjects.
The Investigator will not make any changes in the study or study conduct without IRB/IEC 
approval, except where necessary to eliminate apparent immediate hazards to the subjects. For 
minor changes to a previously approved protocol during the period covered by the original 
approval, it may be possible for the Investigator to obtain an expedited review by the IRB/IEC as 
allowed.
As part of the IRB/IEC requirements for continuing review of approved studies, the Investigator 
will be responsible for submitting periodic progress reports to the IRB/IEC (based on IRB/IEC 
requirements), at intervals appropriate to the degree of subject risk involved, but no less than 
once per year. The Investigator should provide a final report to the IRB/IEC following study 
completion.
UCB (or its representative) will communicate safety information to the appropriate regulatory 
authorities and all active Investigators in accordance with applicable regulatory requirements. 
The appropriate IRB/IEC will also be informed by the Investigator or the Sponsor, as specified 
by the applicable regulatory requirements in each concerned country. Where applicable, 
Investigators are to provide the Sponsor (or its representative) with evidence of such IRB/IEC 
notification.
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15.4
Subject privacy
UCB staff (or designee) will affirm and uphold the subject’s confidentiality. Throughout this 
study, all data forwarded to UCB (or designee) will be identified only by the subject number 
assigned at Screening.
The Investigator agrees that representatives of UCB, its designee, representatives of the relevant 
IRB/IEC, or representatives of regulatory authorities will be allowed to review that portion of the 
subject’s primary medical records that directly concerns this study (including, but not limited to, 
laboratory test result reports, ECG reports, admission/discharge summaries for hospital 
admissions occurring during a subject’s study participation, and autopsy reports for deaths 
occurring during the study).
15.5
Protocol amendments
Protocol changes may affect the legal and ethical status of the study and may also affect the 
statistical evaluations of sample size and the likelihood of the study fulfilling its primary 
objective.
Significant changes to the protocol will only be made as an amendment to the protocol and must 
be approved by UCB, the IRB/IEC, and the regulatory authorities (if required), prior to being 
implemented.
16
FINANCE, INSURANCE, AND PUBLICATION
Insurance coverage will be handled according to local requirements.
Finance, insurance, and publication rights are addressed in the Investigator and/or CRO 
agreements, as applicable.
17
REFERENCES
Augustin M, Glaeske G, Radtke MA, Christophers E, Reich K, Schäfer I. Epidemiology and 
comorbidity of psoriasis in children. Br J Dermatol. 2010;162:633-6.
Christophers E, Barker JN, Griffiths CE, Daudén E, Milligan G, Molta C, et al. The risk of 
psoriatic arthritis remains constant following initial diagnosis of psoriasis among patients seen in 
European dermatology clinics. J Eur Acad Dermatol Venereol. 2010;24:548-54.
Common Terminology Criteria for Adverse Events (CTCAE), Version 4.0. National Institutes of 
Health, National Cancer Institute, Division of Cancer Treatment and Diagnosis. 
http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm. Updated 03 Mar 
2016.
CPMP/ICH/135/95 Note for guidance on Good Clinical Practice (EMEA) Jul 2002.
Dauden E, Griffiths CE, Ortonne JP, Kragballe K, Molta CT, Robertson D, et al. Improvements 
in patient-reported outcomes in moderate-to-severe psoriasis patients receiving continuous or 
paused etanercept treatment over 54 weeks: the CRYSTEL study. J Eur Acad Dermatol 
Venereol. 2009;23(12):1374-82.
Dowlatshahi EA, Wakkee M, Arends LR, Nijsten T. The prevalence and odds of depressive 
symptoms and clinical depression in psoriasis patients: a systematic review and meta-analysis. 
J Invest Dermatol. 2014;134:1542-51.
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Feldman SR. A quantitative definition of severe psoriasis for use in clinical trials. J Dermatolog 
Treat. 2004;15(1):27-9.
Gelfand JM, Neimann AL, Shin DB, Wang X, Margolis DJ, Troxel AB. Risk of myocardial 
infarction in patients with psoriasis. JAMA. 2006;296:1735-41.
Gisondi P, Tessari G, Conti A, Piaserico S, Schianchi S, Peserico A, et al. Prevalence of 
metabolic syndrome in patients with psoriasis: a hospital-based case-control study. 
Br J Dermatol. 2007;157:68-73.
Gottlieb AB. Psoriasis: Emerging therapeutic strategies. Nat Rev Drug Discov. 2005;4:19-34.
Icen M, Crowson CS, McEvoy MT, Dann FJ, Gabriel SE, Maradit Kremers H. Trends in 
incidence of adult-onset psoriasis over three decades: a population-based study. 
J Am Acad Dermatol. 2009;60:394-401.
Krueger G, Ellis CN. Psoriasis–recent advances in understanding its pathogenesis and treatment. 
J Am Acad Dermatol. 2005;53(1 Suppl 1):S94-100.
Krueger G, Koo J, Lebwohl M, Menter A, Stern RS, Rolstad T. The impact of psoriasis on 
quality of Life. Results of a 1998 National Psoriasis Foundation patient-membership survey. 
Arch Dermatol. 2001;137:280-4. 
Kurd SK, Smith N, VanVoorhees A, Troxel AB, Badmaev V, Seykora JT, et al. Oral curcumin 
in the treatment of moderate to severe psoriasis vulgaris: a prospective clinical trial. J Am Acad 
Dermatol. 2008;58:625-31.
Kurd SK, Gelfand JM. The prevalence of previously diagnosed and undiagnosed psoriasis in US 
adults: results from NHANES 2003-2004. J Am Acad Dermatol. 2009;60:218-24.
Langley RG, Krueger GG, Griffiths CEM. Psoriasis: epidemiology, clinical features, and quality 
of life. Ann Rheum Dis. 2005;64(Suppl II):ii18–ii23.
Langley RG, Feldman SR, Han C, Schenkel B, Szapary P, Hsu MC, et al. Ustekinumab 
significantly improves symptoms of anxiety, depression, and skin-related quality of life in 
patients with moderate-to-severe psoriasis: Results from a randomized, double-blind, 
placebo-controlled phase III trial. J Am Acad Dermatol. 2010;63(3):457-65.
Mukhtar R, Choi J, Koo JY. Quality of life issues in psoriasis. Dermatol Clin. 2004;22:389-95. 
Mundt JC, Greist JH, Gelenberg AJ, Katzelnick DJ, Jefferson JW, Model JG. Feasibility and 
validation of a computer-automated Columbia-Suicide Severity Rating Scale using Interactive 
Voice Response Technology. J Psychiatric Res. 2010;44:1224-1228.
Ortonne JP. Redefining clinical response in psoriasis: targeting the pathological basis of disease. 
J Drugs Dermatol. 2004;3:13-20.
Parisi R, Symmons DP, Griffiths CE, Ashcroft DM. Identification and Management of Psoriasis 
and Associated ComorbidiTy (IMPACT) project team. Global epidemiology of psoriasis: A 
systematic review of incidence and prevalence. J Invest Dermatol. 2013;133:377–385.
Posner K, Brown GK, Stanley B, Brent DA, Yershova KV, Oquendo MA, et al. The Columbia-
Suicide Severity Rating Scale: Initial validity and internal consistency findings from three 
multisite studies with adolescents and adults. Am J Psychiatry. 2011;168:1266-1277.
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Rachakonda TD, Schupp CW, Armstrong AW. Psoriasis prevalence among adults in the United 
States. J Am Acad Dermatol. 2014;70:512-6. 
Raychaudhuri SP, Gross J. A comparative study of pediatric onset psoriasis with adult onset 
psoriasis. Pediatric Dermatology. 2000;17(3):174–178.
Snaith RP, Zigmond AS. The Hospital Anxiety and Depression Scale Manual. NFER: Nelson, 
Windsor; 1994.
Ulm K. A simple method to calculate the confidence interval of a standardized mortality ratio. 
Am J Epidemiol. 1990;131(2):373-375.
Yeung H, Takeshita J, Mehta NN, Kimmel SE, Ogdie A, Margolis DJ, et al. Psoriasis severity 
and the prevalence of major medical comorbidity: a population-based study. JAMA Dermatol. 
2013;149:1173-9.
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18
APPENDICES
18.1
Protocol Amendment 1
Rationale for the amendment
The purpose of this amendment is to revise the following: 

Serious adverse event reporting contact information included the wrong fax number for 
Canada and this was corrected

The PtGADA assessment was removed from the protocol, as this assessment is not relevant 
for the study population of patients with psoriasis
Specific changes
Change #1 Serious adverse event reporting
Serious adverse event reporting (24h)
Fax
Europe and Rest of the World: +32 2 386 24 21
USA: +1 800 880 6949
or +1 866 890 3175
Canada: +1 877 582 8842
Email
Global: DS_ICT@ucb.com 
Has been changed to
Serious adverse event reporting (24h)
Fax
Europe and Rest of the World: +32 2 386 24 21
USA and Canada: +1 800 880 6949
or +1 866 890 3175
Canada: +1 877 582 8842
Email
Global: DS_ICT@ucb.com 
Change #2 List of Abbreviations
The table row with PtGADA and its definition was deleted
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Change #3 Section 1 Summary
Original text:
Pharmacokinetic variables are plasma concentrations of bimekizumab. The immunological 
variable is anti-bimekizumab antibody levels prior to and following study treatment. The 
efficacy assessments are PASI, Investigator’s Global Assessment (IGA), body surface area 
(BSA) affected by psoriasis, Patient’s Global Assessment of Disease Activity (PtGADA), and 
the Hospital Anxiety and Depression Scale (HADS); a detailed list of efficacy variables is 
presented in Section 4.4.
Has been changed to: 
Pharmacokinetic variables are plasma concentrations of bimekizumab. The immunological 
variable is anti-bimekizumab antibody levels prior to and following study treatment. The 
efficacy assessments are PASI, Investigator’s Global Assessment (IGA), body surface area 
(BSA) affected by psoriasis, Patient’s Global Assessment of Disease Activity (PtGADA), and 
the Hospital Anxiety and Depression Scale (HADS); a detailed list of efficacy variables is 
presented in Section 4.4.
Change #4 Section 4.4 Efficacy variables
The variable “Change from Baseline in the PtGADA for the arthritis visual analog scale (VAS)” 
was deleted.
Change #5 Table 5-1 Schedule of study assessments
The table row for the PtGADA assessment was deleted. 
The footnote with PtGADA abbreviation definition was deleted.
Change #6 Section 8.1 Baseline Visit
PtGADA assessment was deleted.
Change #7 Section 8.4 Week 12 (±3 days)
PtGADA assessment was deleted.
Change #8 Section 8.6 Week 24 (±3 days)
PtGADA assessment was deleted.
Change #9 Section 8.7 Week 36 (±3 days)
PtGADA assessment was deleted.
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Change #10 Section 8.8 Week 48 (±3 days)
PtGADA assessment was deleted.
Change #11 Section 12 Assessment of Efficacy
The subsection discussing the PtGADA (Section 12.4 PtGADA for the arthritis VAS) was 
deleted.
Change #12 Section 14.5 Planned efficacy analyses
Original text:
Continuous efficacy variables based on the change from Baseline (PASI, BSA, PtGADA, and 
HADS) will be summarized using descriptive statistics by scheduled visit and PS0016 
randomized treatment group and overall.
Has been changed to:
Continuous efficacy variables based on the change from Baseline (PASI, BSA, PtGADA, and 
HADS) will be summarized using descriptive statistics by scheduled visit and PS0016 
randomized treatment group and overall.
18.2
Protocol Amendment 2
Rationale for the amendment
The purpose of this amendment is the following:

Revise the timepoints for the blood sample for anti-bimekizumab antibodies assessment and 
blood sample for bimekizumab plasma concentrations assessment

Specify the study stopping rules
Specific changes
Change #1
Table 5-1 Schedule of study assessments
For the Blood sample for bimekizumab plasma concentrations assessment, the “X” in the Wk 24 
column and the “X” in the Wk 32 column were deleted. An “X” was added to the Wk 28 
column.
Change #2
Table 5-1 Schedule of study assessments
For the Blood sample for anti-bimekizumab antibodies assessment, the “X” in the Wk 24 column 
and the “X” in the Wk 32 column were deleted. An “X” was added to the Wk 28 column.
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Change #3
Section 6.4 Study stopping rules was added
6.4
Study stopping rules
During the study, planned dosing and procedures may be discontinued or suspended for all 
subjects in any part of the study and appropriate follow up procedures established. Where it is 
possible to do so without threatening the safety of subjects, such discontinuation/suspension 
should be discussed with the UCB Study Physician prior to its implementation.
Possible reasons for discontinuation or suspension of the study include (but are not limited to):

A pattern of AEs occurs that contraindicates the further dosing of enrolled / additional 
subjects, including (but not limited to):

More than 1 subject meets any individual Withdrawal Criteria 6, 9, 10, 11 or 12 (as 
provided in Section 6.3), regardless of whether they met the same or different criteria.

Once a second subject meets any of those criteria, referral to the DMC may not be 
delayed while awaiting the outcome of either case.
If the above criteria are reached, the DMC will meet as soon as possible to determine 
whether discontinuation or suspension of the study should occur, and to determine what 
investigations, analyses, procedural amendments, or other actions should occur, before 
making any recommendation regarding the possibility of recommencing the study.  Further 
details on the role of the DMC are provided in Section 9.8.7. 

If the Sponsor or its designees judges it necessary for medical, safety, regulatory, or any 
other reasons consistent with applicable laws, regulations, and GCP.
Change #4
The section heading
8.2
Week 4 (±3 days)
was changed to 
8.2
Week 4 (±3 days); and Week 28 (±3 days)
Change #5
The section heading
8.3
Week 8 (±3 days); Week 16 (±3 days); Week 32 (±3 days); and Week 40 
(±3 days)
was changed to 
8.3
Week 8 (±3 days); Week 16 (±3 days); and Week 40 (±3 days)
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Change #6
The section heading
8.5
Week 20 (±3 days); Week 28 (±3 days); and Week 44 (±3 days)
was changed to
8.5
Week 20 (±3 days); and Week 44 (±3 days)
Change #7
Section 8.6 Week 24 (±3 days)
The following procedures or assessments will be performed prior to administration of study drug
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

Record 12-lead ECG

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine samples for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
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was changed to
The following procedures or assessments will be performed prior to administration of study drug 
(if applicable):

Vital signs (blood pressure, pulse rate, and temperature)

Record 12-lead ECG

C-SSRS

TB questionnaire

PASI

IGA

BSA

HADS

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Bimekizumab plasma concentration

Anti-bimekizumab antibodies

Obtain urine samples for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
Change #8
Section 8.7 Week 32 (±3 days) was added:
8.7
Week 32 (±3 days)
All procedures or assessments will be performed prior to administration of study drug (if 
applicable), unless otherwise noted. The following procedures or assessments will be performed:

Vital signs (blood pressure, pulse rate, and temperature)

C-SSRS

PASI

IGA
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
BSA

Obtain blood samples for:

Standard safety laboratory tests (hematology and biochemistry)

Obtain urine sample for: 

Standard safety laboratory tests (urinalysis)

Urine pregnancy test for women of childbearing potential

Concomitant medications

Record AEs

Contact the IXRS

Study medication administration (after all other visit assessments are completed)
18.3
Protocol Amendment 3
Rationale for the amendment
The purpose of this amendment is to revise the withdrawal criteria to provide instructions for the 
management of subjects with newly diagnosed IBD or with IBD flares during the study. In 
addition, the study contact information was updated.
Modifications and changes
Specific changes
Change #1
Sponsor Study Physician
Name:
 MD, PhD, PharmMed
Address:
UCB Celltech, 208 Bath Rd, Slough, Berkshire, SL1 3WE, UK
Phone:
Was Changed to:
Name:
, MD
Address:
UCB, 208 Bath Rd, Slough, Berkshire, SL1 3WE, UK
Phone:
Change #2
Clinical Trial Biostatistician
Name:
Address:
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, NC 
27617
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Phone:
Fax:
Was changed to:
Name:
Address:
UCB Biosciences, 8010 Arco Corporation Drive, Raleigh, NC 
27617
Phone:
Fax:
Change #3
List of Abbreviations
Inflammatory Bowel Disease (IBD) was added to the list  
Change #4
Section 6.3 Withdrawal criteria
The following was added to the withdrawal criteria:
14. Subjects with newly diagnosed Inflammatory Bowel Disease (IBD) or with IBD flares during 
the study must:

Be referred, as appropriate, to a healthcare professional treating IBD, such as a 
gastroenterologist

Discontinue the 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 judgment in deciding whether the subject should continue in the study and contact 
the Medical Monitor and UCB study physician to confirm the subject's suitability for 
continued participation in the study.
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19
DECLARATION AND SIGNATURE OF INVESTIGATOR
I confirm that I have carefully read and understood this protocol and agree to conduct this 
clinical study as outlined in this protocol, according to current Good Clinical Practice and local 
laws and requirements.
I will ensure that all subinvestigators and other staff members read and understand all aspects of 
this protocol.
I have received and read all study-related information provided to me.
The objectives and content of this protocol as well as the results deriving from it will be treated 
confidentially, and will not be made available to third parties without prior authorization by 
UCB.
All rights of publication of the results reside with UCB, unless other agreements were made in a 
separate contract.
Investigator:
Printed name
Date/Signature
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20
SPONSOR DECLARATION
I confirm that I have carefully read and understand this protocol and agree to conduct this 
clinical study as outlined in this protocol and according to current Good Clinical Practice.
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ELECTRONIC SIGNATURES 
 
Signed by 
Meaning of Signature 
Server Approval Date 
(dd-mon-yyyy 
(HH:mm)) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
PS0018 Protocol Amendment 3 - Phase 2, open-label extension
Clinical Approval
26-Feb-2018 23:02 GMT+01
Clinical Approval
27-Feb-2018 09:06 GMT+01
Clinical Approval
27-Feb-2018 13:33 GMT+01
Clinical Approval
01-Mar-2018 10:00 GMT+01
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