Clinical trial NCT04115748
Conditions: Psoriatic Arthritis
Sponsor: Gilead Sciences
Start date: 2019-12-03; Completion date: 2021-05-11
Enrollment: 67 participants; Allocation: RANDOMIZED; Intervention model: PARALLEL

Brief summary:
The primary objective of this study is to evaluate the effect of filgotinib compared to placebo as assessed by the American College of Rheumatology 20% improvement (ACR20) response in participants with active psoriatic arthritis who are naive to biologic disease-modifying anti-rheumatic drug (DMARD) therapy. The study consists of two parts, the Main Study and the Long Term Extension (LTE).

Detailed description:

Arms: arm 1: Participants will receive filgotinib 200 mg + placebo to match (PTM) filgotinib 100 mg + PTM adalimumab injection for up to 16 weeks. arm 2: Participants will receive PTM filgotinib 200 mg + filgotinib 100 mg + PTM adalimumab for up to 16 weeks. arm 3: Participants will receive PTM filgotinib 200 mg + PTM filgotinib 100 mg + adalimumab 40 mg injection for up to 16 weeks. arm 4: Participants will receive PTM filgotinib 200 mg + PTM filgotinib 100 mg + PTM adalimumab injection for up to 16 weeks. arm 5: Participants will receive filgotinib 200 mg + PTM filgotinib 100 mg for up to 34 weeks. arm 6: Participants will receive PTM filgotinib 200 mg + filgotinib 100 mg for up to 34 weeks.
Interventions: intervention 1: Filgotinib intervention 2: Adalimumab intervention 3: Placebo to match filgotinib intervention 4: Placebo to match adalimumab
Intervention descriptions: intervention 1: Tablets administered orally once daily with or without food intervention 2: Injection administered subcutaneously once every 2 weeks intervention 3: Tablets administered orally once daily with or without food intervention 4: Injection administered subcutaneously once every 2 weeks

Protocol documents:
Prot_000.pdf: 
GILEAU Galapagos 
Study Title: 
Sponsor: 
IND Number: 
EudraCT Number: 
Clinical Trials.gov 
Identifier: 
Indication: 
Protocol ID: 
Gilead Clinical 
Operations: 
PD 
Protocol 
Version/Date: 
CLINICAL STUDY PROTOCOL 
A Phase 3, Randomized, Double-blind, Placebo and 
Adalimumab-controlled Study to Evaluate the Efficacy and Safety 
of Filgotinib in Subjects with Active Psoriatic Arthritis Who Are 
Nai"ve to Biologic DMARD Therapy 
Gilead Sciences, Inc. 
333 Lakeside Drive 
Foster City, CA 94404 
USA 
1155 10 
2019-001996-35 
NCT04115748 
Psoriatic Arthritis 
GS-US-43 1-4566 
Name: 
Telephone: 
Name: 
Telephone: 
Fax: 
Original: 
Amendment 1: 
VHP Amendment 1.1: 
Amendment 2: 
PPD 
PPD 
PPD 
PPD 
PPD 
16 May 2019 
07 August 2019 
11 December 2019 
17 April 2020 
This study wil I be conducted under US Food & Drug Administration IND regulations (21 CFR Part 312); 
however, sites located in the European Economic Area and Switzerland are not included under the IND 
and are considered non-IND sites. 
CONFIDENTIALITY STATEMENT 
The information contained in this document, particularly unpublished data, is the property or under 
control of Gilead Sciences, Inc., and is provided to you in confidence as an investigator, potential 
investigator, or consultant, for review by you, your staff, and an applicable Institutional Review 
Board or Independent Ethics Committee. The information is only to be used by you in connection 
with authorized clinical studies of the investigational drug described in the protocol. You will not 
disclose any of the information to others without written authorization from Gilead Sciences, Inc., 
except to the extent necessary to obtain informed consent from those persons to whom the drug 
may be administered. 


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Protocol GS-US-431-4566 
Gilead Sciences, Inc. 
Final 
Amendment2 
TABLE OF CONTENTS 
TABLE OF CONTENTS .............................................................................................................................................. 2 
LIST OF IN-TEXTTABLES ........................................................................................................................................ 6 
LIST OF IN-TEXT FIGURES ...................................................................................................................................... 6 
PROTOCOL SYNOPSIS .............................................................................................................................................. 7 
GLOSSARY OF ABBREVIATIONS AND DEFCNITION OF TERMS .................................................................... 16 
I. 
INTRODUCTION .............................................................................................................................................. 20 
1.1. 
Background ............................................................................................................................................ 20 
1.2. 
Filgotinib ................................................................................................................................................ 21 
1.2.1. 
General Information ............................................................................................................. 21 
1.2.2. 
Preclinical Pharmacology and Toxicology ........................................................................... 22 
1.2.3. 
Clinical Trials of Filgotinib .................................................................................................. 24 
1.3. 
Information about Humira® (adalimumab) ........................................................................................... 25 
1.4. 
Rationale for This Study ........................................................................................................................ 26 
1.4.1. 
Rationale for Study Design .................................................................................................. 26 
1.4.2. 
Rationale for Dose Selection ................................................................................................ 28 
1.5. 
Risk / Benefit Assessment for the Study ................................................................................................ 29 
1.6. 
Compliance ............................................................................................................................................ 30 
2. 
OBJECTIVES ..................................................................................................................................................... 3 1 
3. 
STUDY DESIGN ................................................................................................................................................ 32 
3.1. 
3.2. 
3.3. 
3.4. 
3.5. 
3.6. 
3.7. 
3.9. -
Endpoints ............................................................................................................................................... 32 
3.1.1. 
Primary Endpoint ................................................................................................................. 32 
3.1.2. 
KeySecondaryE~
·························································································
32 
3.1.3. 
Other Secondary- - Endpoints ....................................................................... 32 
Study Design .......................................................................................................................................... 34 
Study Treatments ................................................................................................................................... 36 
Duration ofTreatment ............................................................................................................................ 37 
Discontinuation Criteria ......................................................................................................................... 37 
3.5.1. 
Study Dtug Interruption Considerations ............................................................................... 37 
3.5.2. 
Study Dtug Discontinuation Considerations ........................................................................ 37 
End of Study ........................................................................................................................................... 39 
Post Stud Care ...................................................................................................................................... 39 
4. 
SUBJECT POPULATION .................................................................................................................................. 42 
4.1. 
Number of Subjects and Subject Selection ............................................................................................ 42 
4.2. 
Inclusion Criteria .................................................................................................................................... 42 
4.3. 
Exclusion Criteria ................................................................................................................................... 44 
4.4. 
MRI Investigation Eligibility Criteria .................................................................................................... 48 
4.4.1. 
MRI Inclusion Criteria: ........................................................................................................ 48 
4.4.2. 
MRI Exclusion Criteria ........................................................................................................ 48 
4.5. 
Screen Failures ....................................................................................................................................... 48 
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5. 
STUDY DRUG ................................................................................................................................................... 50 
5.1. 
Randomization, Blinding and Treatment Codes .................................................................................... 50 
5.1.1. 
Procedures for Breaking Treatment Codes ........................................................................... 50 
5.2. 
Description and Handling of Filgotinib and PTM Filgotinib ................................................................. 51 
5.2.1. 
Formulation of Filgotinib and PTM Filgotinib ..................................................................... 51 
5.2.2. 
Packaging and Labeling of Filgotinib and PTM Filgotinib .................................................. 51 
5.2.3. 
Storage and Handling of Filgotinib and PTM Filgotinib ...................................................... 51 
5.2.4. 
Dosage and Administration ofFilgotinib and PTM Filgotinib ............................................. 52 
5.3. 
Description and Handling of Adalimumab and PTM Adalimumab ....................................................... 52 
5.3.1. 
Formulation of Adalimumab and PTM Adalimumab .......................................................... 52 
5.3.2. 
Packaging and Labeling of Adalimumab and PTM Adalimumab ........................................ 52 
5.3.3. 
Storage and Handling of Adalimumab and PTM Adalimumab ........................................... 53 
5.3.4. 
Dosage and Administration of Adalimumab and PTM Adalimumab .................................. 53 
5.4. 
Prior and Concomitant Medications ....................................................................................................... 53 
5.4.1. 
Concomitant Medications: PsA Related ............................................................................... 54 
5.4.2. 
Concomitant Medications: Non-PsA Related ....................................................................... 56 
5.4.3. 
Prohibited Concomitant Medications ................................................................................... 56 
5.4.4. 
Vaccine Guidelines .............................................................................................................. 57 
5.5. 
Accountability for Study Drugs ............................................................................................................. 57 
5.5. 1. 
Study Dmg Return or Disposal ............................................................................................ 58 
6. 
STUDY PROCEDURES .................................................................................................................................... 59 
6.1. 
Part I - Main Study (Screening through Week 16 Visit) ....................................................................... 59 
6.1.1. 
Screening Visit ..................................................................................................................... 59 
6.1.2. 
Day I Visit ........................................................................................................................... 59 
6.1.3. 
Week 2 Visit through Week 16 Visit ................................................................................... 60 
6.2. 
Part 2 - LTE (After the Week 16 Visit and up to 2 years) ...................................................................... 60 
6.3. 
Early Termination (ET) Visit ................................................................................................................. 60 
6.3.1. 
Main Study Early Termination Visit .................................................................................... 61 
6.3.2. 
LTE Early Termination Visit ............................................................................................... 61 
6.4. 
Completion Visit .................................................................................................................................... 61 
6.5. 
Safety Follow-up Visit ........................................................................................................................... 61 
6.6. 
Study Assessments ................................................................................................................................. 61 
6.6.1. 
Assessment Order ................................................................................................................. 61 
6.6.2. 
Demographics, Medical History, and Physical Exams ......................................................... 62 
6.6.3. 
Efficacy ................................................................................................................................ 62 
6.6.4. 
Safety Assessments .............................................................................................................. 64 
6.6.5. 
Laboratory Assessments ....................................................................................................... 64 
6.6.6. 
Imaging Assessments ........................................................................................................... 67 
7. 
ADVERSE EVENTS AND TOXICITY MANAGEMENT ............................................................................... 69 
7. I. 
Definitions of Adverse Events, Adverse Reactions, and Serious Adverse Events ................................. 69 
7. I. I. 
Adverse Events ..................................................................................................................... 69 
7 .1.2. 
Serious Adverse Events ........................................................................................................ 69 
7.1.3. 
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events ......................................................................... 70 
7.2. 
Assessment of Adverse Events and Serious Adverse Events ................................................................. 70 
7 .2.1. 
Assessment of Causality for Study Drugs and Procedures ................................................... 70 
7 .2.2. 
Assessment of Severity ........................................................................................................ 71 
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7.3. 
Investigator Requirements and Instructions for Reporting Adverse Events and Serious 
Adverse Events to Gilead ....................................................................................................................... 72 
7.4. 
Gilead Reporting Requirements ............................................................................................................. 74 
7.5. 
Clinical Laboratory Abnormalities and Other Abnormal Assessments as Adverse Events or 
Serious Adverse Events .......................................................................................................................... 74 
7.5.1. 
Grades I and 2 Laboratory Abnormality or Clinical Event... ............................................... 75 
7.5.2. 
Grades 3 Laboratory Abnormality or Clinical Event ........................................................... 75 
7.5.3. 
Grades 4 Laboratory Abnormality or Clinical Event ........................................................... 75 
7.6. 
Toxicity Management ............................................................................................................................ 76 
7.6.1. 
Thromboembolic Events ...................................................................................................... 76 
7.7. 
Special Situations Reports ...................................................................................................................... 76 
7.7.1. 
Definitions of Special Situations .......................................................................................... 76 
7.7.2. 
Insttuctions for Reporting Special Situations ....................................................................... 77 
8. 
STA TIS TI CAL CONSIDERATIONS ................................................................................................................ 79 
8.1. 
8.2. 
8.3. 
8.4. 
8.5. 
8.6. 
I 
8.10. 
8.11. 
8.12. 
8.13. 
Analysis Objectives and Endpoints ........................................................................................................ 79 
8.1.1. 
Analysis Objectives .............................................................................................................. 79 
8.1.2. 
Primary Endpoint ................................................................................................................. 79 
8.1.3. 
Secondary Endpoints ............................................................................................................ 79 
Analysis Conventions ............................................................................................................................. 79 
8.2.1. 
Analysis Sets ........................................................................................................................ 79 
Data Handling Conventions ................................................................................................................... 80 
Demographic Data and Baseline Characteristics ................................................................................... 80 
Efficacy Analysis ................................................................................................................................... 80 
8.5.1. 
Primary Analysis .................................................................................................................. 80 
8.5.2. 
Secondary Analyses ............................................................................................................. 81 
8.5.3. 
Hypothesis Testing Strategy ................................................................................................. 82 
Safety Analysis ....................................................................................................................................... 82 
8.6.1. 
Extent of Exposure ............................................................................................................... 83 
8.6.2. 
Adverse Events ..................................................................................................................... 83 
8.6.3. 
Laborator Evaluations ........................................................................................................ 83 
amp e 1ze ............................................................................................................................................ 4 
Data Monitoring Committee .................................................................................................................. 84 
Event Adjudication Committee for Major Adverse Cardiovascular Events and 
Thromboembolic Events ........................................................................................................................ 85 
Week 16 Analysis .................................................................................................................................. 85 
Interim Analysis in L TE ......................................................................................................................... 85 
9. 
RES PONSIBILITIES .......................................................................................................................................... 86 
9.1. 
Investigator Responsibilities .................................................................................................................. 86 
9.1.1. 
Good Clinical Practice .......................................................................................................... 86 
9 .1.2. 
Financial Disclosure ............................................................................................................. 86 
9.1.3. 
Institutional Review Board (IRB) / Independent Ethics Committee (IEC) 
Review and Approval ........................................................................................................... 86 
9.1.4. 
Informed Consent ................................................................................................................. 86 
9.1.5. 
Confidentiality ...................................................................................................................... 87 
9.1.6. 
Study Files and Retention of Records .................................................................................. 87 
9. I. 7. 
Case Report Forms ............................................................................................................... 88 
9.1.8. 
Study Dtug Accountability and Return ................................................................................ 89 
9.1.9. 
Inspections ............................................................................................................................ 89 
9. I. I 0. 
Protocol Comp I iance ............................................................................................................ 89 
9.2. 
Sponsor Responsibilities ........................................................................................................................ 89 
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9 .2.1. 
Protocol Modifications ......................................................................................................... 89 
9.2.2. 
Study Report and Publications ............................................................................................. 90 
9.3. 
Joint Investigator / Sponsor Responsibilities ......................................................................................... 90 
9.3.1. 
Payment Reporting ............................................................................................................... 90 
9 .3 .2. 
Access to Information for Monitoring .................................................................................. 90 
9.3.3. 
Access to Information for Auditing or Inspections .............................................................. 91 
9.3.4. 
Study Discontinuation .......................................................................................................... 91 
10. REFERENCES ................................................................................................................................................... 92 
11 . APP ENDICES .................................................................................................................................................... 94 
Appendix I. 
Appendix 2. 
Appendix 3. 
Appendix 4. 
Appendix 5. 
Appendix 6. 
Appendix 7. 
Appendix 8. 
Appendix 9. 
Appendix I 0. 
Appendix 11 . 
A 
endix 12. 
Appen 1x 17. 
Appendix 18. 
Appendix 19. 
Appendix 20. 
Appendix 21. 
Appendix 22. 
Appendix 23. 
Appendix 24. 
Appendix 25. 
Appendix 26. 
CONFIDENTIAL 
Investigator Signature Page .................................................................................................... 95 
Study Procedures Table .......................................................................................................... 96 
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements ................................................................................................. I 03 
Management of Clinical and Laboratory Adverse Events .................................................... I 07 
Laboratory Assessment Table .............................................................................................. I 08 
Primmy and Key Secondary Null Hypotheses ..................................................................... 109 
Hypothesis Testing Strategy ................................................................................................. 111 
Protocol, Day Numbering ..................................................................................................... 112 
HAQ-DI: Health Assessment Questionnaire - Disability Index .......................................... 113 
F ACIT-Fatigue: Functional Assessment of Chronic Illness Therapy -Fatigue Scale ........... 115 
SF-36v2: 36-Item Short-Fotm Health Survey Version 2 ...................................................... I 16 
PsAlD-12: 12-item Psoriatic Arthritis Im act of Disease uestionnaire ............................. 122 
P ADA: Patient s 
o a Assessment o Disease Activity ................................................. I 
PGAPI: Patient's Global Assessment of Psoriatic Arthritis Pain Intensity ........................... 133 
CASPAR: Classification Criteria for Psoriatic Arthritis ...................................................... 134 
PASI including BSA: Psoriasis Area and Severity Index including Body Surface 
Area ...................................................................................................................................... 135 
mNAPSI: Modified Nail Psoriasis Severity Index ............................................................... 136 
PhGAP: Physician's Global Assessment of Psoriasis ........................................................... 138 
SPARCC Enthesitis Index and LEI: Spondyloarthritis Research Consortium of 
Canada Enthesitis Index and Leeds Enthesitis Index ........................................................... 139 
SJC66 I TJC68: Swollen and Tender Joint Count ................................................................ 140 
LOI: Leeds Dactyl itis Index ................................................................................................. 141 
PhGADA: Physician's Global Assessment of Disease Activity ........................................... 143 
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LIST OF IN-TEXT TABLES
Table 7-1.
Grading of Adverse Event Severity........................................................................................71
Table 7-2
Grading of Upper Respiratory Infection Severity...................................................................72
LIST OF IN-TEXT FIGURES
Figure 3-1.
Study Design ..........................................................................................................................36
Figure 6-1.
Tuberculosis Testing at the Screening Visit ...........................................................................65
Figure 6-2.
Tuberculosis Testing During the LTE....................................................................................66


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PROTOCOL SYNOPSIS
Gilead Sciences, Inc.
333 Lakeside Drive
Foster City, CA 94404
USA
Study Title: 
A Phase 3, Randomized, Double-blind, Placebo and 
Adalimumab-controlled Study to Evaluate the Efficacy and Safety of 
Filgotinib in Subjects with Active Psoriatic Arthritis Who Are Naïve 
to Biologic DMARD Therapy
IND Number:
EudraCT Number:
Clinical Trials.gov 
Identifier:
115510
2019-001996-35
NCT04115748
Study Sites 
Planned:
Approximately 430 sites
Objectives:
The primary objective of this study is:

To evaluate the effect of filgotinib compared to placebo in active 
psoriatic arthritis (PsA) as assessed by the American College of 
Rheumatology 20% improvement (ACR20) response at Week 12
Secondary objectives of this study are:

To evaluate the effect of filgotinib on core domains of PsA as 
assessed by Minimal Disease Activity (MDA) and Very Low 
Disease Activity (VLDA), ACR responses, Psoriasis Area and 
Severity Index including Body Surface Area (PASI including 
BSA) responses, Spondyloarthritis Research Consortium of 
Canada Enthesitis Index and Leeds Enthesitis Index (SPARCC 
Enthesitis Index and LEI), Leeds Dactylitis Index (LDI), Psoriatic 
Arthritis Disease Activity Score (PASDAS), Disease Activity 
Index for Psoriatic Arthritis (DAPSA), Modified Nail Psoriasis 
Severity Index (mNAPSI), and Physician’s Global Assessment of 
Psoriasis (PhGAP)

To evaluate the effect of filgotinib on physical function in active 
PsA as assessed by Health Assessment Questionnaire – Disability 
Index (HAQ-DI)


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
To evaluate the effect of filgotinib on fatigue and quality of life in 
active PsA as assessed by Functional Assessment of Chronic 
Illness Therapy – Fatigue Scale (FACIT-Fatigue), 36-item 
Short-Form Health Survey Version 2 (SF-36v2), and 12-item 
Psoriatic Arthritis Impact of Disease (PsAID-12)

To evaluate the efficacy of filgotinib versus adalimumab in active 
PsA as assessed by ACR20 response

To evaluate the safety and tolerability of filgotinib

See Section 2 for full list of study objectives
Study Design:
This is a randomized, double-blind, placebo- and active-controlled, 
Phase 3 study in adult male and female subjects with active PsA who 
have had an inadequate response or intolerance to 1 or more therapies 
for PsA, such as conventional synthetic disease-modifying 
anti-rheumatic drugs (csDMARDs), apremilast and / or non-steroidal 
anti-inflammatory drugs (NSAIDs), but have never received a biologic 
DMARD (bioDMARD) for PsA or psoriasis.
The study consists of two parts, the Main Study: Screening through 
Week 16 (inclusive) and the Long Term Extension (LTE): after 
Week 16 for 2 years.
After all subjects have completed the Week 16 Visit or have 
permanently discontinued the study prior to Week 16, the treatment 
assignments will be unblinded to the Sponsor only. The subjects and 
investigators will remain blinded to individual level treatment 
assignment.
Part 1 – Main Study (Screening through Week 16):
Approximately 854 subjects will be randomized in a 2:2:1:2 ratio to 
one of 4 dosing groups as outlined below.
Randomization will be stratified by geographic region and concurrent 
use of csDMARD(s) and / or apremilast at randomization (yes or no).
Subjects will be permitted, but are not required, to continue stable 
doses of background csDMARD(s), apremilast, and / or NSAIDs. 
Every effort should be made to maintain stable background therapy for 
PsA treatment through the completion of the Week 16 Visit. 
Instructions for rescue therapy are detailed in Section 5.4.


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Dosing groups in the Main Study:

Filgotinib 200 mg group: filgotinib 200 mg once daily + placebo 
to match (PTM) filgotinib 100 mg once daily + PTM adalimumab 
subcutaneous (SC) injection once every two weeks (q2w)

Filgotinib 100 mg group: PTM filgotinib 200 mg once 
daily + filgotinib 100 mg once daily + PTM adalimumab SC 
injection q2w

Active comparator group: PTM filgotinib 200 mg once 
daily + PTM filgotinib 100 mg once daily + adalimumab 40 mg 
SC injection q2w

Placebo control group: PTM filgotinib 200 mg once daily + PTM 
filgotinib 100 mg once daily + PTM adalimumab SC injection q2w
NOTE: All subjects will discontinue adalimumab / PTM injections by 
the Week 16 Visit (the last injections should be at approximately 
Week 14).
Part 2 – LTE (After the Week 16 Visit for 2 years):
After completion of the Main Study, subjects who have not 
permanently discontinued study drug will continue on to the LTE as 
follows:

Those who were assigned to the filgotinib groups will continue on 
the same study drug assignments

Those who were assigned to the placebo or active comparator 
groups will be reassigned 1:1 in a blinded fashion to filgotinib 
200 mg or 100 mg once daily
Dosing groups in the LTE:

Filgotinib 200 mg group: filgotinib 200 mg once daily + PTM 
filgotinib 100 mg once daily

Filgotinib 100 mg group: PTM filgotinib 200 mg once 
daily + filgotinib 100 mg once daily
Discontinuation of Study Drug:
For the first 16 weeks of study participation, subjects who temporarily 
interrupt or permanently discontinue study drug for any reason are to 
continue with study visits and assessments through the Week 16 Visit, 
per Section 3.5 unless the subject withdraws consent, is lost to 
follow-up, and / or continued participation in the study is medically 
contraindicated, per investigator’s judgment. Study drug interruption 
and discontinuation considerations are outlined in Section 3.5. All 
subjects who permanently discontinue study drug should continue to 
receive standard of care treatment for their PsA including additional 
therapies, if required.


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Discontinuation of Study Participation:
If a subject is unable to complete the study through the Week 16
Visit, and has received at least one dose of study drug, the subject 
will complete an Early Termination (ET) Visit at the time of study 
discontinuation. Subjects will also complete a post-study follow-up 
visit approximately 4 weeks later (Safety Follow-up Visit).
After the Week 16 Visit, subjects who permanently discontinue study 
drug for any reason are to discontinue the study. Subjects who exit 
the study early, regardless of dosing duration, are to complete an ET 
Visit and a Safety Follow-up Visit.
Number of Subjects 
Planned:
Approximately 854
Target Population:
Subjects with active PsA despite non-bioDMARD therapies: 
csDMARD(s), apremilast and / or NSAID(s)
Duration of 
Treatment:
Approximately 2.25 years
Diagnosis and Main 
Eligibility Criteria:
For a complete list of study inclusion and exclusion criteria, please 
refer to Section 4.2 and 4.3.
Key Eligibility Criteria
Key Inclusion Criteria:

Male or female subjects who are 18-75 years of age (19-75 years 
of age at sites in Republic of Korea, 20-75 years of age at sites in 
Japan and Taiwan) on the day of signing initial informed consent

Meet Classification Criteria for Psoriatic Arthritis (CASPAR) and 
have a history consistent with PsA ≥6 months at Screening
Part 1 : Main Study 
Part 2: Long Tenn Extension 
Screening 
(<28 days) 
Day 1 
Randomization 
(2:2:1:2) 
Week16 
FIL 100 mg 
Fil 100 mg 
Re-Randomization 
(1 :1) 
.... 2.25 years 


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
Have active PsA defined as ≥3 swollen joints (from a 66 swollen 
joint count [SJC]) and ≥3 tender joints (from a 68 tender joint 
count [TJC]) at Screening and Day 1; these may or may not be 
the same joints at Screening and Day 1

Must have a documented history or active signs of at least one of 
the following at Screening:
a) Plaque psoriasis
b) Nail changes attributed to psoriasis

Have had inadequate response or intolerance to ≥1 csDMARD, 
apremilast and / or NSAID, administered over the course of 
≥12 weeks for the treatment of PsA, as per local 
guidelines / standard of care

If continuing csDMARD(s) during the study, subjects are 
permitted to use only a maximum of 2 of the drugs as outlined 
in Section 4.2 and must have been on this treatment for 
≥12 consecutive weeks prior to Screening, with a stable dose and 
route of administration (defined as no change in prescription) for 
≥4 weeks prior to Day 1

Concomitant NSAIDs or corticosteroids are permitted as 
specified in Sections 4.2 and 4.3.
Key Exclusion Criteria

Prior PsA or psoriasis treatment with a bioDMARD

Prior exposure to a JAK inhibitor >2 doses

Any active / recent infection, as specified in Section 4.3

Any chronic and / or uncontrolled medical condition that would 
put the subject at increased risk during study participation or 
circumstances which may make a subject unlikely or unable to 
complete or comply with study procedures and requirements, per 
investigator judgement

Any moderately to severely active musculoskeletal or skin 
disorder other than PsA or plaque psoriasis that would interfere 
with assessment of study parameters, as per judgement of 
investigator
NOTE: Prior history of reactive arthritis or axial spondyloarthritis is 
permitted if there is documentation of change in diagnosis to PsA or 
additional diagnosis of PsA


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
Any history of an inflammatory arthropathy with onset before age 
16 years old

Active autoimmune disease that would interfere with assessment 
of study parameters or increase risk to the subject by participating 
in the study (e.g. uveitis, inflammatory bowel disease, 
uncontrolled thyroiditis, systemic vasculitis, transverse myelitis), 
per judgement of investigator

Presence of any extra-articular manifestations typically associated 
with rheumatoid arthritis (RA), such as rheumatoid nodules, 
rheumatoid lung, or other signs / symptoms, as per judgement of 
investigator

Pregnancy or nursing females

Active drug or alcohol abuse, as per judgement of investigator

Unwilling or unable to follow protocol requirements
Magnetic Resonance Imaging (MRI) Investigation Key Eligibility 
Criteria
Key MRI Inclusion Criteria:

Subject must fulfill criteria for entry to the Main Study

Subject must have PsA joint involvement at a minimum in one 
hand / wrist as confirmed by the investigator at Screening. The 
same hand / wrist (R or L) should be imaged at all subsequent 
MRIs, regardless of PsA activity.

Subject’s baseline MRI must fulfill at least one of the below 
criteria by central reading:
a) Definitive intra-articular MRI synovitis 
OR
b) Definitive MRI osteitis
Key MRI Exclusion Criteria
NOTE: Subject may still participate in the Main Study / LTE if 
ineligible for the MRI investigation. Reasons for ineligibility may 
include, but are not limited to:

Inability or medical contraindication for an MRI examination 
(e.g. presence of a pacemaker, defibrillator, or other 
contraindicated implanted metallic device, such as anterior 
interbody cages, aneurysm clip or pedicle screws, severe 
claustrophobia or weight >350 lbs./158 kg)

Metallic fragments embedded anywhere in the body OR 
pigment-containing tattoos in the area of examination


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• 
Known or potential risk of adverse reaction to gadolinium-based 
contrast agents, including but not limited to, allergy or 
compromised renal function, per investigator judgement 
• 
Very difficult peripheral intravascular access 
• 
Site or region was not selected by Sponsor to perfonn MRis 
Study Procedures/ 
Refer to Study Procedures Table Appendix 2. 
Frequency: 
Test Product, Dose, 
and Mode of 
Administration: 
Reference Therapy, 
Dose, and Mode of 
Administration: 
Criteria for 
Evaluation: 
Safety: 
Efficacy: 
CONFIDENTIAL 
200 mg filgotinib orally once daily 
100 mg filgotinib orally once daily 
Adalimmnab 40 mg SC injection (active comparator) or PTM SC q2w 
PTM filgotinib 200 mg orally once daily 
PTM filgotinib 100 mg orally once daily 
Safety will be assessed by the documentation of AEs, physical 
examinations, vital signs, and clinical laboratory parameters at 
specified time points during the study. 
The primary endpoint is the ACR20 response at Week 12. 
The key secondary endpoints include: 
• 
ACR50 response at Week 12 
• 
Change from Baseline in HAQ-DI at Week 12 
• 
Change from Baseline in SF-36v2 physical component smmnary 
(PCS) at Week 16 
• 
Change from Baseline in LEI at Week 16, in subjects with 
enthesitis at Baseline 
• 
Psoriasis Area and Severity Index 75% improvement (PASI75) 
response at Week 16, in subjects with psoriasis covering ~3% of 
the BSA at Baseline 
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• 
MDA response at Week 16 
• 
Change from Baseline in FACIT-Fatigue at Week 16 
Final 
Amendment2 
• 
Change from Baseline in LDI at Week 16, in subjects with 
dactylitis at Baseline 
Statistical Methods: 
The primary analysis set for efficacy analyses will be the Full 
Analysis Set, which includes all randomized subjects who received at 
least one dose of study drug. The primary analysis set for safety 
analyses will be the Safety Analysis Set, which includes all subjects 
who received at least one dose of study drug. 
CONFIDENTIAL 
All continuous efficacy endpoints will be summarized using an 
8-nmnber summary (n, mean, standard deviation [SD], 
median, P1quartile [Ql], 3rd quartile [Q3], minimum, maximum) by 
treatment group. All categorical efficacy endpoints will be 
summarized with the number and percentage of subjects who meet the 
endpoint or category definition by treatment group. 
Safety endpoints will be smmnarized with the nmnber and percentage 
of subjects with events or abnonnalities for categorical values or 
8-number smmnary (n, mean, SD, median, Q 1, Q3, minimum, 
maximum) for continuous data by treatment group. 
A pre-specified Week 16 analysis is planned after all randomized 
subjects have completed their Week 16 Visit (or prematurely 
discontinued from the study prior to Week 16). The time point of the 
primary efficacy endpoint is Week 12. The time points of the key 
secondary efficacy endpoints are either Week 12 or Week 16. 
The primary efficacy estimand corresponds to the treatment policy 
strategy. A logistic regression analysis with treatment groups and 
stratification factors in the model will be used to analyze the primary 
endpoint. 
The graphical approach to sequentially rejective multiple test 
procedures (Appendix 6 and Appendix 7) will be used to control a 
family-wise type I error rate at 5% (i.e. a = 0.05). Within each 
filgotinib dosing regimen, the primary hypothesis will be first tested 
at o/2. If the primary hypothesis is rejected, then the next secondary 
hypothesis in the same filgotinib dosing regimen will be tested at o/2. 
Testing of the hypotheses happens sequentially in the same filgotinib 
dosing regimen. Once all hypotheses within the same filgotinib 
dosing regimen are rejected, then the respective a/2 can be passed on 
to the other regimen's hypotheses, that is, all hypotheses in the other 
filgotinib dosing regimen will be tested at a level. 
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Two safety estimands, treatment policy and while on treatment, will 
be applied for the safety analysis.
Sample size is determined based on the non-inferiority test of each 
filgotinib group compared to the adalimumab group on the ACR20 
response rate at Week 12. When assuming the ACR20 response rate 
being 52% and 60% for the adalimumab and each filgotinib group, 
and 38.6% for the placebo group, 244 subjects in each filgotinib 
group and placebo group, and 122 subjects in the adalimumab group
are required to obtain 90% power at a two-sided 0.025 significance 
level to demonstrate that filgotinib group preserves more than 50% of 
the effect of adalimumab with respect to the ACR20 response rate at 
Week 12.  
A sample size of 244 subjects in each filgotinib group and the placebo 
group will provide over 95% power to detect a difference in ACR20 
response rate of 21.4% at Week 12 (38.6% and 60% for the placebo 
group and each filgotinib group, respectively) using a two-sided 
0.025 significance level superiority test.
In summary, the total sample size will be approximately 854 subjects.
This study will be conducted in accordance with the guidelines of Good Clinical Practice (GCP) 
including archiving of essential documents.


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GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS
Ab
antibody
ACR
American College of Rheumatology
ADA
adalimumab
ADL
Activities of Daily Living
ADME
absorption, distribution, metabolism, and excretion
AE
adverse event
ALT
alanine aminotransferase
anti-TNF
anti-tumor necrosis factor
ApoA1 / B
Apolipoprotein A1 / B
AST
aspartate aminotransferase
ATP
adenosine triphosphate
AUC
area under the curve
bioDMARD
biologic DMARD
BSA
body surface area
CASPAR
Classification Criteria for Psoriatic Arthritis
CD
Crohn’s disease
CES
carboxylesterases
CIA
collagen-induced arthritis
CK
creatine kinase
CNS
central nervous system
eCRF
electronic case report form
CRO
contract research organization
CRP
C-reactive protein
csDMARDs
conventional synthetic disease-modifying anti-rheumatic drugs
CSR
clinical study report
CTCAE
Common Terminology Criteria for Adverse Events
CVEAC
Cardiovascular Event Adjudication Committee
CYP
cytochrome P450
DAPSA
Disease Activity in Psoriatic Arthritis
DAS28
Disease Activity Score 28
DBP
diastolic blood pressure
DLQI
Dermatology Life Quality Index
DMC
Data Monitoring Committee
DSS
dextran sulphate sodium
ECG
electrocardiogram
EDC
Electronic Data Capture
EQ-5D-5L
EuroQol 5 Dimensions with 5 Levels
CCI-


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eSAE
Electronic Serious Adverse Event
ET
Early Termination
FACIT-Fatigue
Functional Assessment of Chronic Illness Therapy – Fatigue Scale
FAS
Full Analysis Set
FDA
Food and Drug Administration
GCP
Good Clinical Practice
GI
gastrointestinal
GSI
Gilead Sciences, Inc.
h
hours
HAQ-DI
Health Assessment Questionnaire - Disability Index 
HbA1c
Hemoglobin A1c
HBsAg
HBV surface antigen
HBV
hepatitis B virus
HCRU
Healthcare Resource Utilization Questionnaire
HCV
hepatitis C virus
HDL
high-density lipoprotein
HDPE
high density polyethylene
hERG
human ether-a-gogo related gene
HIV
human immunodeficiency virus
HLA-B27
Human Leukocyte Antigen B27
HLGT
High-Level Group Term
HLT
High-Level Term
HR
heart rate
IB
investigator’s brochure
IBD
inflammatory bowel disease
IC50
inhibitory concentration
ICF
Informed consent form
ICH
International Conference on Harmonization
IL
interleukin
IRB / IEC
Institutional Review Board or Independent Ethics Committee
IXRS
Interactive Voice / Web Response System
JAK
janus kinase
LDA
low disease activity
LDI 
Leeds Dactylitis Index 
LDL
low-density lipoprotein
LEF
leflunomide
LLT
Lower-Level Term 
LTE
Long Term Extension
MACEs
major adverse cardiovascular events
MCS
Mental Component Score


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MDA
Minimal Disease Activity
MedDRA
Medical Dictionary for Regulatory Activities
MMRM
mixed-effect model repeated measures
mNAPSI
Modified Nail Psoriasis Severity Index
MSS
Medical Safety Science
MRI
Magnetic Resonance Imaging
MTX
methotrexate
NOELs
no-observed-effect-levels
NSAIDs
non-steroidal anti-inflammatory drugs
NYHA
New York Heart Association
OATs
organic anion transporters
PASDAS
Psoriatic Arthritis Disease Activity Score
PASI including BSA
Psoriasis Area and Severity Index including Body Surface Area
PASI75
Psoriasis Area and Severity Index 75% improvement
PCS
physical component summary
PD
pharmacodynamics
PDE4
phosphodiesterase 4
PEG
polyethylene glycol
PGADA
Patient’s Global Assessment of Disease Activity
PGAPI
Patient’s Global Assessment of PsA Pain Intensity
P-gp
P-glycoprotein
PhGADA
Physician’s Global Assessment of Disease Activity
PhGAP 
Physician’s Global Assessment of Psoriasis 
PK
Pharmacokinetic
PROs
Patient Reported Outcomes
PsA
psoriatic arthritis
PsAID-12
12-item Psoriatic Arthritis Impact of Disease
PsAMRIS
Psoriatic Arthritis Magnetic Resonance Imaging Score
PsARC
Psoriatic Arthritis Response Criteria
PT
Preferred Term
PTM
placebo to match
PVE
Pharmacovigilance and Epidemiology
Q1
1st quartile
q2w
Once every two weeks
Q3
3rd quartile
qd
Once daily
QFT
QuantiFERON® TB Gold Plus
RA
rheumatoid arthritis
SADRs
serious adverse drug reactions
SAE
Serious adverse events


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SAP
Statistical Analysis Plan
SBP
systolic blood pressure
SC
subcutaneous
SD
standard deviation
SF-36v2
36-item Short-Form Health Survey Version 2
SI
International System of Units
SJC66 / TJC68
Swollen and Tender Joint Count
SmPC
Summary of Product Characteristics
SOPs
Standard Operating Procedures
SPARCC Enthesitis 
Index and LEI
Spondyloarthritis Research Consortium of Canada Enthesitis Index and Leeds Enthesitis 
Index
SSZ
sulfasalazine
STAT
signal transducer and activator of transcription
SUSARs
suspected unexpected serious adverse reactions
TB
Tuberculosis
TBNK
T and B lymphocyte and natural killer
TDC
Tender dactylitis count
TEAEs
Treatment-Emergent Adverse Events
Tgras
transgenic
TNF-α
tumor necrosis factor α
TYKs
tyrosine kinases
UC
Ulcerative Colitis
UGTs
uridine 5’-disphosphate glucuronosyltransferases
ULN
upper limit of normal
vfPBMCs
viably frozen peripheral blood mononuclear cells
VHP
Voluntary Harmonisation Procedure
VL
Viral load
VLDA
Very Low Disease Activity
WPAI-PsA
Work Productivity and Activity Impairment for Psoriatic Arthritis


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1.
INTRODUCTION
1.1.
Background
Psoriatic arthritis (PsA) is an inflammatory joint disease associated with psoriasis and 
characterized by heterogeneous musculoskeletal phenotypes that involve multiple domains 
including the peripheral joints, axial skeleton, tendon and ligament insertion sites (enthesitis) and 
digits (dactylitis). PsA occurs in approximately 30% of psoriasis patients {Gladman 2005}. In 
the majority of cases (75%) psoriasis precedes joint disease, but in some cases (15%) the onset is 
synchronous and in 10% arthritis precedes psoriasis. In the latter, unrecognized psoriasis may be 
found or there may be a history of widespread guttate psoriasis in childhood or a strong family 
history {Ritchlin 2017}.
PsA occurs with equal frequency in males and females. The arthritis in PsA commonly involves 
distal joints and has the tendency to distribute in a ray pattern where all the joints of a single digit 
are more likely to be affected. The presence of erythema over affected peripheral joints, 
asymmetrical spinal involvement, and enthesitis are also typical features of PsA 
{Gladman 2005}. PsA belongs to the group of spondyloarthropathies with spondylitis being 
present in up to 40% of patients. The extra-articular features observed in PsA are similar to other 
spondyloarthropathies including mucous membrane lesions, iritis, urethritis, diarrhea and aortic 
root dilatation, and association with Human Leukocyte Antigen B27 (HLA-B27) 
{Gladman 2005}.
First-line treatment traditionally consists of NSAIDs and csDMARDs such as sulfasalazine 
(SSZ), methotrexate (MTX) and leflunomide (LEF). These drugs remain a mainstay of therapy 
where there is limited access to biological agents {Gossec 2012}. The arrival of anti-tumor 
necrosis factor (anti-TNF) agents over a decade ago dramatically increased the treatment 
armamentarium for PsA leading to improved outcomes for both skin and joint disease 
{Gladman 2007, Mease 2006}. Nevertheless, anti-TNF agents do not work in all patients and 
response may diminish over time, partly because of immunogenicity {Mease 2013}. Novel 
biologic agents with different mechanisms of action that target the interleukin(IL)-23 and 
IL-17 pathways that promote skin and joint inflammation as well as oral agents including janus 
kinase (JAK) inhibitors and the phosphodiesterase E4 inhibitor, apremilast, have recently 
become available as therapeutic options for PsA as well {Ritchlin 2016}.
Several key cytokines in the IL-23 / IL-17 pathways promote skin and joint inflammation 
through signaling via the JAK pathway. Activated JAKs recruit and activate signal transducer 
and activator of transcription (STATs) which in turn drive gene transcription {O'Shea 1997}. In 
December 2017, tofacitinib (Xeljanz®) became the first JAK inhibitor to receive Food and Drug 
Administration (FDA) approval for the treatment of adult patients with PsA. Tofacitinib is a 
small molecule, has strong binding affinity for JAK1 and JAK3, and weaker affinity for JAK2. 
The extensive pre-clinical and clinical development programs demonstrated its mechanisms of 
action via anti-inflammatory and immunosuppressive effects. The drug proved to be efficacious 
in treating the signs and symptoms of PsA. However, the observed side effects and risk profile of 
tofacitinib are similar to those of several existing anti-rheumatic agents with cytopenias, elevated 


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levels of liver function enzymes, increased total cholesterol levels, with increase in LDL 
typically exceeding those for HDL, and increased risk for infections including serious and 
opportunistic infections. At higher doses, tofacitinib treatment was associated with anemia, 
which is thought to be linked to inhibition of JAK2 {Gladman 2017, Mease 2017a, 
Mease 2017b}.
While the pan-JAK inhibitor tofacitinib has shown an early onset of action and long-term 
efficacy in PsA, limitations of therapy include side effects potentially mediated by its effect on 
JAK2 and JAK3. This highlights the need for more selective and targeted therapies with 
improved immunomodulatory and hematologic effects. JAK1 is thought to be an integral part of 
PsA pathogenesis due its role in transmitting inflammatory cytokine signaling. Hence, targeted 
inhibition of JAK1 has great potential for the treatment of PsA with an improved safety and side 
effect profile.
1.2.
Filgotinib
1.2.1.
General Information
Janus kinases are intracellular cytoplasmic tyrosine kinases (TYKs) that transduce cytokine
signaling from membrane receptors through STAT to the nucleus of cells. JAK inhibitors block 
the signaling of various cytokines, growth factors, and hormones, including the 
pro-inflammatory cytokine IL-6. Four different types of JAKs are known, JAK1, JAK2, JAK3, 
and TYK2 which co-interact with different sets of membrane receptors. Inhibition of JAKs is a 
promising therapeutic option for a range of inflammatory conditions including RA, UC, and 
Crohn’s disease (CD).
Filgotinib (GS-6034, formerly GLPG0634) is a potent and selective inhibitor of JAK1. The
compound has shown good preliminary efficacy in PsA {Mease 2018}, ankylosing spondylitis 
{van der Heijde 2018}, RA and CD patients in Phase 2 (filgotinib IB). In a Phase 3 RA study 
with subjects who failed prior biologic therapy, filgotinib achieved all primary and key 
secondary endpoints {Genovese 2018}. Additionally, filgotinib is currently under assessment in 
ongoing Phase 3 RA, UC, CD studies (clinicaltrials.gov).
In humans, filgotinib is metabolized to form one major active metabolite GS-829845 
(formerly G254445). Though the potency of this metabolite is lower than the parent molecule, 
the overall exposure and peak plasma concentration in humans is higher than seen in all tested 
animal species. As a consequence, dedicated pharmacology and toxicology studies have been 
performed with GS-829845. Results from pharmacodynamics (PD) testing in healthy volunteers 
suggest that the clinical activity of filgotinib could result from the combination of the parent 
molecule and the metabolite.
For further information on filgotinib, refer to the current investigator’s brochure (IB) for 
filgotinib.


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1.2.2.
Preclinical Pharmacology and Toxicology
Filgotinib and its metabolite, GS-829845 have been extensively characterized in nonclinical 
studies. This program includes cellular assays demonstrating potency and selectivity of the
compound against JAK1; efficacy studies in rats and mice; repeat dose toxicity studies (up to
26 weeks in the rat and 39 weeks in the dog), in vitro and in vivo safety pharmacology and
genetic toxicology studies, and reproductive toxicology studies in rats and rabbits. Additional
toxicology studies conducted include phototoxicity studies and dose-range finding studies in
support of a definitive rat juvenile toxicity study and a 6 month carcinogenicity study in
transgenic (TgrasH2) mice. A 2-year rat oral carcinogenicity study as well as the pre- and 
post-natal development toxicity study in rats were completed.
1.2.2.1.
Primary and Secondary Pharmacology
Filgotinib is an adenosine triphosphate (ATP)-competitive inhibitor of JAK1. It is highly
selective for inhibition of JAK1 over 451 other kinases evaluated in vitro. In cellular assays, it
inhibits JAK / STAT-driven processes with half maximal inhibitory concentration (IC50) values
from 179 nM onwards. In human whole blood, JAK1 is inhibited by filgotinib with an IC50 of
629 nM and exhibits approximately 30-fold selectivity over JAK2. Filgotinib demonstrated
significant efficacy in the rat collagen-induced arthritis (CIA) model as well as in the mouse
dextran sulphate sodium (DSS)-induced colitis model.
Metabolite GS829845 exhibits a similar JAK1 selectivity profile but is approximately 
10 to 20-fold less potent than the parent filgotinib in in vitro assays. GS-829845 was as effective 
as filgotinib in the rat CIA model, but at doses that required a 10-fold higher exposure.
1.2.2.2.
Safety Pharmacology
Filgotinib and GS-829845 had no effects on the respiratory system and central nervous system 
(CNS) up to respectively 40 and 5-fold the exposure in RA subjects given filgotinib 200 mg once 
daily.
Filgotinib and GS-829845 had no relevant effects on cardiovascular parameters 
(human ether-a-gogo related gene [hERG] and dog telemetry studies), apart from a slight 
non-adverse increase in heart rate and arterial pressure with GS829845 at exposures 7fold that of 
the Cmax in subjects with RA treated with 200 mg once daily filgotinib. There were no relevant 
effects on ECG and QT.
1.2.2.3.
Nonclinical Absorption, Distribution, Metabolism, and Excretion (ADME)
Filgotinib demonstrates good oral bioavailability in mice, rats, dogs, and minipigs but less in
monkeys. Plasma protein binding is low (<70%) in all species, including humans. The PK of 
filgotinib is generally dose proportional without gender differences. No accumulation occurs 
with repeated dosing. The mean terminal half-life after oral administration is 4 and 5 hours (h) in 
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In the rat, filgotinib showed a rapid and even distribution throughout the body. High
concentrations were observed only in the gastrointestinal (GI) tract and urinary bladder.
Filgotinib does not penetrate into CNS tissues. The distribution of filgotinib indicates some 
affinity for melanin-containing tissues.
Excretion is nearly complete within 72 h (mouse), 24 h (rat) and 48 h (dog) post-dosing. In the 
mouse, an average of 54.0 and 37.7% of the administered radioactivity was excreted in feces and 
urine, respectively. In the rat, fecal and urinary excretion accounted for 40% and 59% of the 
administered dose, respectively. In bile-duct cannulated rats bile secretion of about 15%. In the 
dog, fecal excretion was the primary route of excretion, accounting for 59% of the administered 
dose, with urinary excretion accounting for 25%.
In vitro metabolism studies in all species revealed one major metabolite (GS-829845). The
formation of GS-829845 is mediated by carboxylesterases (CES) and is not dependent on
cytochrome P450 (CYP).
In vitro experiments have shown that drug-drug interactions with filgotinib and GS-829845 are
unlikely. There is no inhibition or induction of CYPs or uridine 5’-disphosphate
glucuronosyltransferases (UGTs), and no relevant inhibition of key drug transporters, including
the organic anion transporters (OATs) involved in the renal elimination of MTX, by filgotinib or
GS-829845.
1.2.2.4.
Nonclinical Toxicology
In repeat oral dose toxicity studies in both rats and dogs, the primary target tissues identified for
filgotinib were the lymphoid tissues which are expected based on the pharmacology of JAK
inhibition. Additional filgotinib-related findings were observed in the male reproductive organs
of both species, and in the incisor teeth of rats only. Effects on the lymphoid system were fully
reversible. Testicular toxicity demonstrated partial reversibility; however, sperm counts 
remained low. A dose of 200 mg / day of filgotinib results in an estimated mean clinical area 
under the curve (AUC) of 2.80 μg∙h / mL, which represents an exposure margin of 2.3, 1.8, and 
3.4-fold when considering the mean AUC in male dogs at the no-observed-effect-levels 
(NOELs) in the 26 week and 39 week chronic toxicity studies, and the 39 week targeted 
exposure toxicity study, respectively.
GS-829845 related findings in general repeat dose toxicity studies were similar to those of the
parent filgotinib; however, no testicular toxicity was noted following administration of
GS-829845.
Filgotinib and GS-829845 were non-genotoxic when evaluated in the bacterial mutagenicity
assay, the in vitro mouse lymphoma mutagenicity assay, and the rat bone marrow micronucleus
assay.


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In embryofetal development studies, filgotinib and GS-829845 caused embryolethality and
teratogenicity in rats and rabbits at exposures similar to the human exposure at 200 mg once 
daily of filgotinib in subjects with RA. Administration of filgotinib did not affect female fertility,
but impaired fertility was observed in male rats at exposures approximately 15-fold the human
exposure at 200 mg of filgotinib in subjects with RA. GS-829845 did not have any effects on
fertility parameters in either male or female rats.
In an in vitro phototoxicity study in 3T3 cells, the metabolite GS-829845 was positive for
phototoxic potential and results with filgotinib were equivocal. A follow-up in vivo rat
phototoxicity assay revealed a lack of phototoxic potential for both compounds.
1.2.3.
Clinical Trials of Filgotinib
Comprehensive data from the Phase 1 and 2 programs are available to support development into
Phase 3. An overview of exposure and clinical studies conducted with filgotinib is available in 
the IB.
Phase 2 Filgotinib PsA Study GLGP0634-CL-224 (EQUATOR)
The EQUATOR study was a randomized, double-blind, placebo controlled Phase 2 trial that 
enrolled adults with active moderate to severe PsA fulfilling Classification Criteria for Psoriatic 
Arthritis (CASPAR), active or documented history of plaque psoriasis, and an inadequate 
response or intolerance to at least one csDMARD. Subjects were randomized to receive either 
placebo or filgotinib 200 mg once daily for 16 weeks. The primary objective of the study was to 
evaluate efficacy of filgotinib compared to placebo at Week 16.
The percentage of ACR20 responders was statistically significantly higher in filgotinib group at 
Week 16 compared to placebo. Subjects with previous TNFi therapy had a similar ACR20 
response compared to the rest of the study population. The percentage of ACR50 and 
70 responders was also statistically significantly higher at Week 16 compared to placebo.
A dose response was observed for all three parameters. Starting at Week 1 response was 
observed for ACR20 and ACR50 in the filgotinib group and remained statistically significantly 
superior to placebo through Week 16.
Subjects receiving filgotinib also demonstrated significantly higher clinical efficacy compared to 
placebo at Week 16 with additional PsA assessments including Disease Activity in Psoriatic 
Arthritis (DAPSA) score, Psoriatic Arthritis Response Criteria (PsARC) response, PASDAS, and 
SPARCC Enthesitis Index. The filgotinib group achieved improvement in skin manifestations of 
disease as demonstrated by the PASI75 score and the pruritus numeric rating scale, both of 
which were statistically significantly better than placebo at Week 16.
Patient reported outcomes including the HAQ-DI, FACIT-Fatigue, and PsA related pain intensity 
also improved with filgotinib at Week 16 compared to placebo.


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Safety analysis showed similar proportions of filgotinib and placebo recipients had at least one 
treatment-emergent AE; 37 (57%) for filgotinib, and 39 (59%) for placebo. Six subjects had an 
event that was grade 3 or 4. The most frequently occurring events were nasopharyngitis and 
headache, occurring at similar proportions in each group. One serious treatment-emergent AE 
was reported in each group (pneumonia [filgotinib] and hip fracture after a fall [placebo]). The 
SAE of pneumonia was a fatal event. No gastric perforations, malignancies, lymphomas, venous 
thromboembolic events, opportunistic infections, or cases of active tuberculosis (TB) were 
reported. There was one case of herpes zoster confined to a single dermatome in the filgotinib 
group. The incidence of infections was similar between the two groups.
Phase 3 Filgotinib Rheumatoid Arthritis Study GS-US-417-0302 (FINCH 2)
FINCH 2 was a randomized, double-blind, placebo-controlled, add-on, Phase 3 study in adult 
male and female subjects with active RA despite csDMARD(s) therapy (i.e. MTX, 
hydroxychloroquine, sulfasalazine, leflunomide) who had an inadequate response or were 
intolerant to at least 1 bioDMARD. Subjects were randomized 1:1:1 to receive once daily 
filgotinib 200 mg, filgotinib 100 mg, or placebo for 24 weeks all in the context of a stable dose 
of permitted csDMARD(s). The primary endpoint was the proportion of subjects who achieved 
an ACR20 response at Week 12.
At Week 12, an ACR20 response was achieved by significantly more subjects receiving 
filgotinib 200 mg or 100 mg than placebo (66.0%, 57.5% and 31.1%, respectively; both 
p<0.001). The reduction from Baseline in HAQ-DI at Week 12 was greater in the filgotinib 
200 mg and 100 mg groups compared to the placebo group (-0.55 and -0.48 vs -0.23, 
respectively; both p<0.001). Other key secondary endpoints, including SF-36v2 and 
FACIT-Fatigue, were also met at both filgotinib doses.
The safety profile was consistent with data from the Phase 2 studies with filgotinib. AE rates 
were similar for filgotinib 200 mg, filgotinib 100 mg and placebo groups (69.4% and 
63.4% vs 67.6%, respectively) as were rates of serious adverse events (SAEs) (4.1%, 5.2% and 
3.4%, respectively. There were 4 cases of uncomplicated herpes zoster (2 in each filgotinib 
group). There was one non-serious AE of retinal vein occlusion in the filgotinib 200 mg group; 
no other venous thrombotic events were reported. Two adjudicated major adverse cardiovascular 
events (MACEs) were reported: one subarachnoid hemorrhage in the placebo group and one 
myocardial ischemia in the filgotinib 100 mg group. There were no cases of opportunistic 
infection / active TB, malignancy, GI perforation or death.
1.3.
Information about Humira(adalimumab)
For information on the study drug adalimumab being used as an active comparator, refer to the 
current package insert.


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1.4.
Rationale for This Study
Therapeutic options for the treatment of PsA have increased dramatically over the past 15 years 
resulting in markedly improved outcomes for skin and joint disease {Gladman 2007, 
Mease 2006}. The arrival of anti-TNF agents represented a major treatment advance because 
these therapies are very effective for skin and all of the musculoskeletal domains of PsA. Despite 
of significant uptake in the use of anti-TNF agents, tolerability due to allergic and autoimmune 
reactions, loss of response due to immunogenicity and increased risk of infections / opportunistic
infections remain problematic{Mease 2013}. Agents with different mechanisms of action that 
target the IL-23 / IL-17 pathways have recently become available. Use of these biological 
parenterally administered agents has led to marked skin clearance, while musculoskeletal 
symptoms improvement, the effect observed is similar to that with anti-TNF agents. Apremilast, 
an oral inhibitor of phosphodiesterase 4 (PDE4) offers modest response in the skin and joint
symptoms with few safety signals. Therefore, there is still a need for simple, orally administered 
agents with novel and targeted mechanisms of action that can effectively improve PsA outcome 
in all of its domains, and which are well-tolerated and have an acceptable safety profile.
Tofacitinib, an orally administered JAK1 / JAK3 inhibitor, is approved for use in patients with 
PsA based on the data from two Phase 3 studies in subjects with PsA. In the Phase 3 study 
evaluating tofacitinib versus placebo in subjects with active PsA and previous inadequate 
response to TNF inhibitors, the ACR20 responses were 50% with the 5 mg dose of tofacitinib as 
compared with 24% with placebo (p<0.001) after 3 months of treatment. In the Phase 3 study 
evaluating tofacitinib versus placebo and adalimumab in patients with active PsA and inadequate 
response to csDMARDs, the ACR20 response rate at month 3 was 50% in the 5 mg tofacitinib 
group as compared with 33% in the placebo group (p = 0.01). Safety results were similar across 
the two studies in regards to the number and category of AEs. Both studies reported cases of 
herpes zoster, serious infections and malignancy in the subjects exposed to tofacitinib 
{Gladman 2017, Mease 2017a}.
The JAK1 selective inhibitor filgotinib targets an intracellular tyrosine kinase dysregulated in 
subjects with inflammatory disorders including PsA. Filgotinib is a small molecule for oral daily 
administration that demonstrated clinical efficacy in treating the signs and symptoms of active 
PsA in a Phase 2 study as well as other inflammatory disorders including RA. 
1.4.1.
Rationale for Study Design
Study GS-US-431-4566 is a randomized, double-blind, placebo and adalimumab-controlled 
study evaluating the efficacy and safety of 2 doses of filgotinib administered once daily in 
subjects with active PsA despite previous non-biologic DMARD therapies: csDMARDs, 
apremilast, and / or NSAID(s). The study consists of 2 parts:

Part 1: The Main Study, is from Screening through the Week 16 Visit

Part 2: LTE immediately follows Part 1 and starts after the Week 16 Visit continuing for 
2 years

Total study duration is ~ 2.25 years.


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The objectives of the study are to evaluate the effect of filgotinib compared to placebo and 
adalimumab on the signs and symptoms, physical function, and quality of life in PsA. Safety and
tolerability of filgotinib will also be assessed.
Treatment duration of 12 weeks to assess the primary endpoint is considered optimal to evaluate 
the potential benefit of filgotinib on a variety of musculoskeletal symptoms of PsA. The effect of 
filgotinib on the arthritis component is expected to be fast (in previous studies with filgotinib in 
RA, ACR20 plateaued at Week 8). However, the effect on enthesitis and dactylitis requires 
longer duration of treatment as observed in recently published studies with other compounds.
The duration of placebo will be limited. All subjects in the placebo arm will be reallocated in a 
blinded manner 1:1 to 100 mg or 200 mg of filgotinib at Week 16. Given the slowly progressive 
nature of PsA, 16 weeks of placebo on accepted background therapy is considered both clinically 
and ethically appropriate and allows an acceptable time period in which to assess initial response 
to therapy. The use of placebo is critical in evaluating subject reported and subjective outcomes, 
which can be highly variable and influenced by placebo therapy. The placebo effect is 
well-established in PsA studies and inclusion of the placebo arm is critical to evaluation of the 
overall risk-benefit profile of added filgotinib therapy. Finally, the provision of best supportive
care in the context of the trial, as well as the limited duration and eventual opportunity for
subjects to transition to filgotinib, make the use of placebo ethically acceptable for the specified
duration.
This study includes an active comparator, adalimumab, a monoclonal antibody directed against
tumor necrosis factor α (TNF-α). The inclusion of the active comparator will allow comparison
of the efficacy and safety of filgotinib to an approved and frequently prescribed product
indicated for use in this patient population.
The study eligibility criteria are consistent with those of recent clinical trials evaluating novel
investigational treatments for PsA. Subjects should meet the CASPAR criteria for PsA. Subjects 
are required to have active disease defined as ≥3 swollen and ≥3 tender joints at both Screening 
and Day 1 Visits. In addition, subjects are required to have a history of or active psoriasis lesion. 
The study duration of ~2.25 years allows sufficient time for demonstrating the safety and 
tolerability of therapy, reduction in disease activity, and confirmation that clinical benefit is 
sustained over time.
1.4.1.1.
Rationale for Outcome Measures
The ACR responses, MDA, and PASDAS are considered reliable measures of response to 
treatment and disease activity in subjects with PsA. The psoriasis disease activity will be 
assessed by the PASI50, PASI75, PASI90, PASI100 and PhGAP. Psoriatic nail involvement will 
be recorded by using the mNAPSI. Several other disease activity measures will be assessed 
including SPARCC Enthesitis Index and LEI (for enthesitis), LDI (for dactylitis), 
 
, and PhGADA.
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Assessing quality of life (measured by the HAQ-DI, FACIT-Fatigue, SF-36v2, PsAID-12, 
EuroQol 5 Dimensions with 5 Levels (EQ-5D-5L), and PGAPI) at the Day 1 Visit and during the 
course of study treatment provides insight into the effects on modifying PsA disease course and 
impact on daily life. Assessing the change in economic impact (WPAI-PsA), and Healthcare 
Resource Utilization Questionnaire (HCRU)) of PsA over the course of the study provides 
insight into the subject’s ability to work and other daily activities as well as the impact on the 
burden of healthcare resources.
1.4.2.
Rationale for Dose Selection
Enrolled subjects will be randomized to receive filgotinib (100 mg or 200 mg), active 
comparator (adalimumab), or placebo. The doses of filgotinib chosen for evaluation in this study,
100 mg and 200 mg once daily, are supported by a combination of safety and efficacy data from 
Phase 1 and 2 studies in the clinical development program, and the known dose-pSTAT1 
inhibition relationship of filgotinib.
In two Phase 2a studies in subjects with RA (Study GLPG0634-CL-201 and -202), dosing with 
filgotinib was well tolerated and achieved a high level of efficacy at a 200 mg daily dose 
(ACR20 response of 75-92% at Week 4). Administration of a higher filgotinib dose (300 mg) did 
not demonstrate greater efficacy, therefore, the highest dose to be tested in this study will be 
200 mg once daily. In two Phase 2b studies, filgotinib at daily doses of 50 mg, 100 mg, or 
200 mg, administered in addition to a background therapy with MTX (GLPG0634-CL-203) or as 
monotherapy (GLPG0634-CL-204) was shown to be safe and efficacious in subjects with 
moderately to severely active RA who had an inadequate response to MTX alone. In the Phase 2 
PsA study (GLPG0634-CL-224), filgotinib 200 mg once daily was well tolerated and achieved a 
high level of efficacy at a 200 mg daily dose as well (ACR20 response rate of 80% at Week 16).
Exposure-response analysis based on data from all Phase 2 studies indicated a dose-dependent 
increase in efficacy (ACR20 / 50 / 70, Disease Activity Score 28 (DAS28) [C-reactive protein 
(CRP)]), with a plateau at the 200 mg total daily dose on the dose-response curve. Additionally, 
in Study GLPG0634-CL-203, no statistically significant difference in efficacy was observed at 
200 mg daily dose, administered as 200 mg once daily or 100 mg twice daily. These results are 
consistent with the relationship observed between filgotinib exposures and pSTAT1 activation 
(ex-vivo) following single and multiple filgotinib doses, where maximal inhibition of pSTAT1 
(~78%) was achieved at or above 200 mg total daily dose and intermediate inhibition (~47%) at 
100 mg {Namour 2015}.
Safety data collected across Phase 2 clinical studies showed no dose-dependent trends in the
incidence of AEs or SAEs, including infections, or laboratory abnormalities with the exception
of a numerical increase in select gastrointestinal AEs (e.g. nausea, vomiting, abdominal pain, and
upper abdominal pain). This numerical increase was observed in the 200 mg compared to the
100 mg dose. However, the overall frequency was low and clinical relevance is unknown.
Filgotinib, administered at a dose of 100 mg or 200 mg daily, was found to be safe and well
tolerated. The safety profile was consistent with that observed for an immunomodulatory
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Overall, the 100 mg and 200 mg once daily dosing regimens have been proposed based on the
known dose-pSTAT1 inhibition relationship of filgotinib and the clinical experience (safety and 
efficacy) with PsA and RA subjects in Phase 2 studies. Inclusion of two doses in the proposed 
Phase 3 trials will enable establishment of an appropriate nominal dose for the treatment of PsA 
and determine the regimen with the most favorable risk / benefit profile in these populations.
1.5.
Risk / Benefit Assessment for the Study
As of June 2018, 6605 subjects have received filgotinib either as single doses or multiple doses, 
and 1278 subjects have received daily filgotinib for >1 year. In general, filgotinib has been safe 
and well tolerated in all populations studied. In addition to PsA, large Phase 3 programs in RA, 
CD and ulcerative colitis (UC) are currently ongoing as well.
Nonclinical studies in rats and dogs identified the testes and lymphoid tissue as target organs for 
filgotinib in long term repeat-dose toxicity studies. In both species, histopathological changes in 
the testes included germ cell depletion and degeneration, with reduced sperm content and 
increased cell debris in the epididymis and reduction in fertility in rats. The dog was determined 
to be the most sensitive species. A dose of 200 mg / day of filgotinib results in an estimated 
mean clinical AUC of 2.8 μg∙h / mL, which represents an exposure margin of 2.3, 1.8, and 
3.4-fold when considering the mean AUC in male dogs at the NOELs in the 26 week and 
39 week chronic toxicity studies, and the 39 week targeted exposure toxicity study, respectively. 
Decreased lymphocytes observed in nonclinical studies have not been shown in clinical studies.
Filgotinib has shown an increased risk of embryofetal malformations at exposures similar to
human doses; the use of highly effective contraception in the subject population will be
implemented in the study to mitigate this risk.
No clinically relevant impact on cardiovascular parameters (including vital signs and ECG),
respiratory or neurologic function has been observed in Phase 1 and 2 trials of filgotinib, 
including a dedicated Phase 1 study to evaluate the effect of filgotinib on the QT / QTc interval 
in healthy subjects. The QT study evaluated filgotinib at doses of 200 mg and 450 mg; neither 
dose led to prolongation in the QTc interval or was associated with clinically significant ECG 
changes. In Phase 2 trials in RA, filgotinib was well tolerated. In the RA studies (including the 
open label extension DARWIN 3), infections were reported more commonly in the filgotinib 
groups, including serious infections leading to hospitalization, and even death. The most 
common system organ classes with AEs were infections and infestations, and GI disorders. Dose
dependent decreases in the Phase 2b studies were observed in mean neutrophil counts and
platelet counts (but mean changes in both remained within normal laboratory reference ranges)
and there were no decreases in lymphocytes or lymphocyte subsets. Hemoglobin levels slightly
improved (increased) with filgotinib treatment, confirming that no anemia was induced. Mild and
clinically insignificant serum creatinine increases were noted in both Phase 2b studies, with
stabilization by Week 24. Neutrophil decreases (in the RA population) and a potential increased
risk of infection may be considered risks consistent with the mechanism of JAK inhibition.


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Overall clinical findings and laboratory changes are consistent with selective JAK1 inhibition
and based on Phase 2 data the expected benefit of using filgotinib as proposed in this study is
considered to outweigh any associated risks.
Adalimumab is a TNFα inhibitor that is indicated and commonly used in the target population of
this trial with well-established safety and efficacy profile (Humira (US) Package Insert, 
Humira (EU) Summary of Product Characteristics (SmPC)).
The dose and duration of adalimumab treatment proposed in this study are in line with posology
approved globally (Humira US Package Insert, Humira EU SmPC).
Risks associated with the use of adalimumab are well characterized, and are described in
approved local product information. Adalimumab is associated with an increased risk for
developing serious infections that may lead to hospitalization or death. Opportunistic infections
due to bacterial, mycobacterial, invasive fungal, viral, parasitic, or other opportunistic pathogens
have been reported with TNFα inhibitors. Reactivation of latent TB has been reported. All
subjects will be tested for TB before study start as outlined in the exclusion criteria and will be
carefully monitored for signs and symptoms of infection during and after the study. Study drug
will be discontinued for serious infections as outlined in Section 3.5. An increase of
nonmelanoma skin cancers, hematologic cancers and a potential increase of other cancers have 
been reported with use of TNFα inhibitors. Subjects will undergo regular assessments, including
physical examination and hematological assessments.
TNFα inhibitors are commonly used as first line therapy in this patient population. Their efficacy
has been well established. Overall, the benefit of using adalimumab as proposed in this study is 
considered to outweigh any associated risks.
An independent Data Monitoring Committee (DMC) appointed to monitor the study (with the 
initial DMC data review after the first 100 subjects across the program, Study GS-US-431-4566 
and Study GS-US-431-4567, complete 12 weeks of treatment) will provide an additional level of 
risk mitigation. The overall risk / benefit balance of this study is considered favorable. For 
additional information about the risks of filgotinib, reference is made to the investigator 
brochure.
1.6.
Compliance
This study will be conducted in compliance with this protocol, Good Clinical Practice (GCP), 
and all applicable regulatory requirements.


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OBJECTIVES 
The primary objective of this study is: 
Final 
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• 
To evaluate the effect of filgotinib compared to placebo in active PsA as assessed by the 
ACR20 response at Week 12 
The secondary objectives of this study are: 
• 
To evaluate the effect of filgotinib on core domains of PsA ( e.g. peripheral arthritis, psoriatic 
skin disease, enthesitis and dactylitis) as assessed by MDA, VLDA, ACR responses, PASI 
including BSA responses, SPARCC Enthesitis Index and LEI, LDI, PASDAS, DAPSA, 
mNAPSI, and PhGAP. 
• 
To evaluate the effect of filgotinib on physical function in active PsA as assessed by 
HAQ-DI 
• 
To evaluate the effect of filgotinib on fatigue and quality of life in active PsA as assessed by 
FACIT-Fatigue, SF-36v2, and PsAID-12 
• 
To evaluate the efficacy of filgotinib versus adalimumab in active PsA as assessed by 
ACR20 
• 
To evaluate the safety and tolerability of filgotinib 
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3.
STUDY DESIGN
3.1.
Endpoints
3.1.1.
Primary Endpoint
The primary endpoint is the ACR20 response at Week 12.
3.1.2.
Key Secondary Endpoints
The key secondary endpoints include:

ACR50 response at Week 12

Change from Baseline in HAQ-DI at Week 12

Change from Baseline in SF-36v2 physical component summary (PCS) at Week 16

Change from Baseline in LEI at Week 16, in subjects with enthesitis at Baseline

PASI75 response at Week 16, in subjects with psoriasis covering ≥3% of the BSA at 
Baseline

MDA response at Week 16

Change from Baseline in FACIT-Fatigue at Week 16

Change from Baseline in LDI at Week 16, in subjects with dactylitis at Baseline
3.1.3.
Other Secondary
 Endpoints
Other secondary
 endpoints will be evaluated at all scheduled or applicable time 
points in the Main Study other than the time points that are already specified in the primary and 
key secondary endpoints.
The other secondary endpoints include: 

Change from Baseline in PASDAS

MDA response 

VLDA response

Change from Baseline in DAPSA

Change from Baseline in PhGAP, in subjects with psoriasis covering ≥3% of the BSA at 
Baseline
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Change from Baseline in mNAPSI, in subjects with psoriatic nail involvement at Baseline

Change from Baseline in LEI, in subjects with enthesitis at Baseline

Change from Baseline in PsAID-12

PASDAS low disease activity (LDA, i.e. PASDAS ≤3.2)

PASDAS remission (i.e. PASDAS ≤1.9)

ACR20 response

ACR50 response

ACR70 response

Change from Baseline in individual components of the ACR response criteria

Change from Baseline in DAS28(CRP)

DAS28(CRP) LDA

DAS28(CRP) remission

Time to achieve DAS28(CRP) LDA

DAPSA LDA

DAPSA remission

Time to achieve DAPSA LDA

PsARC response

Change from Baseline in PASI, in subjects with psoriasis covering ≥3% of the BSA at 
Baseline

PASI50 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

PASI75 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

PASI90 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

PASI100 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

Change from Baseline in SPARCC Enthesitis Index, in subjects with enthesitis at Baseline


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Change from Baseline in LDI, in subjects with dactylitis at Baseline 
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• 
Change from Baseline in tender dactylitis com1t (TDC), in subjects with dactylitis at Baseline 
• 
Change from Baseline in HAQ-DI 
• 
Change from Baseline in FACIT-Fatigue 
• 
Change from Baseline in SF-36v2 PCS and mental component score (MCS) 
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3.2. 
Study Design 
This is a randomized, double-blind, placebo and active-controlled, Phase 3 study in adult male 
and female subjects with active PsA who have had an inadequate response or intolerance to 1 or 
more therapies for PsA, such as csDMARDs, apremilast and / or NSAIDs, but have never 
received a bioDMARD for PsA or psoriasis. 
The study consists of two parts, the Main Study which is the Screening Visit through Week 16 
(inclusive) and the LTE which is after the Week 16 Visit up to ~2.25 years. 
Adult male and female subjects with active PsA will be screened to detennine eligibility as per 
the inclusion and exclusion criteria, see Sections 4.2 and 4.3 respectively. The Screening period 
will be up to 28 days. Extensions to the screening timeline, exclusively due to imaging, will be 
considered by the Medical Monitor or designee; approval in writing will be required. Written 
infonned consent must be obtained before any study-related procedures take place. Subjects will 
be randomized in a 2:2: 1 :2 ratio to filgotinib 200 mg, filgotinib 100 mg, active comparator 
(adalimmnab), or matching placebo controls administered for up to 16 weeks in a double-blind 
fashion. The last self-injection of adalimmnab (ADA) / PTM is scheduled at 14 weeks. At the 
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Week 16 Visit, subjects who have not permanently discontinued study drug will continue on to 
the LTE as follows:

Those who were assigned to the filgotinib groups will continue on the same study drug 
assignments

Those who were assigned to the placebo or active comparator groups will be reassigned 
1:1 to filgotinib 100 mg or 200 mg once daily
For the first 16 weeks of study participation, subjects who temporarily interrupt or permanently 
discontinue blinded study drug for any reason are to continue with study visits and assessments 
through the Week 16 Visit, per Section 3.5, unless the subject withdraws consent, is lost to 
follow-up, and / or continuation in the study is medically contraindicated, per investigator’s 
judgment. Study drug interruption and discontinuation considerations are outlined in Section 3.5
and include serious infections, inadequate response or loss of response, per investigator 
judgement. All subjects who permanently discontinue study drug should continue to receive 
standard of care treatment for their PsA.
Concomitant medications are to remain stable throughout the Main Study; however, after the 
Week 16 Visit assessments have been completed, investigators may adjust the dose of any of the 
subject’s background medications for management of PsA disease activity, as per Section 5.4.
After all subjects have completed the Week 16 Visit or have permanently discontinued the study 
prior to Week 16, the treatment assignments will be unblinded to the Sponsor only. The subjects 
and investigators will remain blinded to individual level treatment assignment.
The assessments planned to be performed at each visit are detailed in the Study Procedures Table
(Appendix 2). A schedule of the study design is provided below.


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Figure 3-1.
Study Design
Four weeks after the subject’s final visit (end of study or ET Visit), a Safety Follow-up will be 
performed via phone for all subjects, unless otherwise required.
3.3.
Study Treatments
Approximately 854 subjects will be randomized in a 2:2:1:2 ratio to one of 4 dosing groups.
Dosing groups in the Main Study:

Filgotinib 200 mg group: filgotinib 200 mg once daily + placebo to match (PTM) filgotinib 
100 mg once daily + PTM adalimumab SC injection q2

Filgotinib 100 mg group: PTM filgotinib 200 mg once daily + filgotinib 100 mg once 
daily + PTM adalimumab SC injection q2w

Active comparator group: PTM filgotinib 200 mg once daily + PTM filgotinib 100 mg once 
daily + adalimumab 40 mg SC injection q2w

Placebo control group: PTM filgotinib 200 mg once daily + PTM filgotinib 100 mg once 
daily + PTM adalimumab SC injection q2w
Dosing groups in the LTE:

Filgotinib 200 mg group: filgotinib 200 mg once daily + PTM filgotinib 100 mg once daily
Part 1: Main Study 
Part 2: Long Tenn Extension 
Screening 
(~28 days) 
Day 1 
Randomization 
(2:2:1:2) 
Placebo (n=244) 
Week 16 
FIL 100 mg 
[ 1 FIL 200 mg 
' ' ' ' 
FIL 100 mg 
Re-Randomization 
(1 :1) 
- 2.25 years 


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
Filgotinib 100 mg group: PTM filgotinib 200 mg once daily + filgotinib 100 mg once daily
3.4.
Duration of Treatment
Subjects are planned to participate in the study for ~2.25 years: the Main Study for 16 weeks and 
LTE for 2 years.
3.5.
Discontinuation Criteria
3.5.1.
Study Drug Interruption Considerations
Study drug interruption should be considered in the following circumstances below. Gilead 
Medical Monitor should be consulted if the principal investigator believes discussion is 
warranted.

Intercurrent illness that would, in the judgment of the investigator, affect assessments of 
clinical status to a significant degree.

Subject is scheduled for elective or emergency surgery (excluding minor skin procedures
under local or no anesthesia); timing of study drug pausing should be determined in
consultation with the Gilead Medical Monitor or its designee.

Any subject who develops a new infection during the study should undergo prompt and
complete diagnostic testing appropriate for an immunocompromised individual, and the
subject should be closely monitored.
NOTE: During the time of study drug interruption for any of the above, the subject should 
continue to have study visits as scheduled in Appendix 2 and to take part in procedures and 
assessments, if deemed medically appropriate by the investigator.
3.5.2.
Study Drug Discontinuation Considerations
The Gilead Medical Monitor or its designee should be consulted prior to study drug 
discontinuation when medically feasible.
Study medication should be permanently discontinued in the following instances:

Any opportunistic infection

Any serious infection that requires antimicrobial therapy or hospitalization

Complicated herpes zoster infection (with multi-dermatomal, disseminated, ophthalmic, or 
CNS involvement)

Evidence of active hepatitis C virus (HCV) during the study, as evidenced by HCV RNA 
positivity


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
Evidence of active hepatitis B virus (HBV) during the study, as evidenced by HBV DNA 
positivity

Any thromboembolic event that meets SAE reporting criteria

Uncontrolled disease activity, per the investigator’s judgment 

Unacceptable toxicity, or toxicity that, in the judgment of the investigator, compromises the 
subject’s ability to continue study-specific procedures or is considered to not be in the 
subject’s best interest

Subject request to discontinue for any reason

Pregnancy during the study

Discontinuation of the study at the request of Gilead, a regulatory agency or an Institutional 
Review Board or Independent Ethics Committee (IRB / IEC)

Subject use of prohibited concurrent therapy may trigger study drug discontinuation;
consultation should be made with the Gilead Medical Monitor or its designee

Laboratory criteria 
a) 2 sequential neutrophil counts <750 neutrophils / mm3 (International System of Units 
(SI): <0.75x109 cells / L)
b) 2 sequential platelet counts <75,000 platelets / mm3 (SI: <75.0x109 cells / L)
c) 2 sequential values for estimated creatinine clearance <35 mL / min based on the 
Cockroft Gault Formula
d) 2 sequential aspartate aminotransferase (AST) or alanine aminotransferase (ALT)
elevations >3x upper limit of normal (ULN) and ≥1 total bilirubin value >2xULN or 
accompanied by symptoms consistent with hepatic injury
e) 2 sequential AST or ALT elevations >5xULN
While the above lab criteria are for study drug discontinuation, actions should be taken 
after any of these abnormalities occur at any one time (e.g. a single neutrophil count 
<750 neutrophils / mm3 [SI: <0.75x109 cells / L]) by conducting an unscheduled visit to 
perform a re-test of the abnormal result within 3 to 7 days (except creatinine, which 
should be retested 7-14 days apart).
NOTE: In each case of elevated AST or ALT, there is a need for additional 
investigations, such as review of ethanol, recreational drug and dietary supplement 
consumption; testing for acute hepatitis A, B or C infection and biliary tract imaging 
should be promptly discussed with the study Medical Monitor.


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Subjects who pennanently discontinue study drug for any reason, including pregnancy, are to 
receive standard of care treatment for their PsA as detenn ined by the investigator, and those 
subjects should continue study participation m1til the Week 16 Visit, if deemed medically 
appropriate by the investigator. 
If there are any questions regarding pennanent discontinuation, these should be discussed with 
the Sponsor or its designee. 
3.6. 
End of Study 
End of Study is defined as when the last subject has completed all scheduled dosing 
(~2.25 years) plus their Safety Follow-up Visit or the study has been tenn inated. 
3.7. 
Post Study Care 
After the subject has completed their study participation, the long-tenn care of the participant 
will remain the responsibility of the participant and / or their primary treating physician. 
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3.9. 
MRI Investigation 
Final 
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At capable sites (i.e. qualifying equipment, local regulatory approval, etc.) a subset of subjects 
(approximately 50 per dosing group) will undergo MRI evaluation with gadolinium. These 
subjects must provide consent and meet the entrance criteria for MRI in Section 4.4, MRis with 
gadolinium of a single hand / wrist will be perfonned at two time points: Screening and at the 
Week 16 Visit. Detennination of whether to image the subject's right or left hand / wrist will be 
up to the judgment of the investigator, depending on clinical findings for disease activity at 
Screening. The same hand / wrist must be scanned for the Week 16 MRI. Subjects may withdraw 
consent from the MRI investigation at any time during the Main Study. 
Subjects who fail the entry criteria of the MRI investigation with the first MRI, or who do not 
continue onto the Week 16 MRI, may be replaced by consenting additional subjects. Further 
details of the MRI investigation and procedural requirements will be provided to sites in a 
separate manual. 
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4.
SUBJECT POPULATION
4.1.
Number of Subjects and Subject Selection
A sufficient number of subjects will be screened to ensure that ~854 subjects with active PsA 
will be randomized to one of 4 dosing groups.
4.2.
Inclusion Criteria
Subjects must meet all of the following inclusion criteria to be eligible for participation in this 
study.
1) Male or female subjects who are 18-75 years of age (19-75 years of age at sites in Republic 
of Korea, 20-75 years of age at sites in Japan and Taiwan) on the day of signing initial 
informed consent
2) Meet CASPAR and have a history consistent with PsA ≥6 months at Screening
3) Have active PsA defined as ≥3 swollen joints (from a 66 SJC) and ≥3 tender joints (from a 
68 TJC) at Screening and Day 1; these may or may not be the same joints at Screening and 
Day 1
4) Must have a documented history or active signs of at least one of the following at Screening:
a) Plaque psoriasis
b) Nail changes attributed to psoriasis
5) Have had inadequate response or intolerance to ≥1 csDMARD, apremilast and / or NSAID, 
administered over the course of ≥12 weeks for the treatment of PsA, as per local 
guidelines / standard of care
6) If continuing csDMARD(s) during the study, subjects are permitted to use only a maximum 
of 2 of the following drugs and must have been on this treatment for ≥12 consecutive weeks 
prior to Screening, with a stable dose and route of administration (defined as no change in
prescription) for ≥4 weeks prior to Day 1:
a) MTX oral or SC up to 25 mg / week (must include concomitant use of a folic / folinic
acid supplementation as per local standard of care / investigator judgment; MTX use may 
not be combined with leflunomide during the study)
b) Leflunomide up to 20 mg once daily orally (may not be combined with MTX during the 
study)
c) Sulfasalazine up to 3 g daily orally


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d) Hydroxychloroquine up to 400 mg daily or chloroquine up to 250 mg daily
e) Apremilast up to 30 mg twice daily orally
f)
Azathioprine up to 200 mg daily orally
g) Cyclosporine up to 300 mg daily orally
7) If csDMARDs are stopped prior to Day 1, the following washout periods are required:
a) ≥4 weeks prior to Day 1: apremilast, sulfasalazine, azathioprine, MTX, 
hydroxychloroquine
b) ≥8 weeks prior to Day 1: oral cyclosporine
c) Leflunomide must either have a washout period of ≥8 weeks prior to Day 1 or ≥4 weeks 
prior to Day 1 if 11 days of standard cholestyramine therapy was completed
8) If taking NSAIDs, dose must be kept stable (defined as no change in prescription) for 
≥2 weeks prior to Day 1
9) If taking oral corticosteroids, dose must be ≤10 mg / day of prednisone or equivalent, and be 
kept at a stable dose (defined as no change in prescription) for ≥4 weeks prior to Day 1
10) If using topical therapies for psoriasis (e.g. topical corticosteroids, coal tar, salicylic acid, 
vitamin D analogs, retinoids, anthralin, topical calcineurin inhibitors such as tacrolimus) dose 
must be stable (defined as no change in prescription) ≥2 weeks prior to Day 1
11) Meet one of the following TB Screening criteria:
a) No evidence of active or latent TB, which is defined as having ALL of the following:
i)
A negative QuantiFERON® TB-Gold Plus test at Screening
AND
ii) A chest radiograph (views as per local guidelines) taken at Screening or within the 
3 months prior to Screening (with the report or films available for investigator 
review) without evidence of active or latent TB infection
AND
iii) No history of either untreated or inadequately treated latent or active TB infection


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b) For subjects with prior latent TB:
i)
A completed course of therapy, as per local standard of care, for latent TB (9 months 
of isoniazid in a location where rates of primary multi-drug resistant TB infections 
are <5% or an acceptable alternative regimen) WITH a chest X-ray within 3 months 
prior to or at Screening
In these cases, no QuantiFERON® TB-Gold Plus test (or equivalent assay) need be 
obtained. A chest radiograph with the report or films must be available for 
investigator review.
NOTE: Cases falling under category “b” need to be approved in writing by the Sponsor or its 
designee prior to enrollment in the study. Subjects with currently ACTIVE TB are not 
allowed in the study, regardless of past or present anti-TB medication use. Subjects with a 
new diagnosis of latent TB during screening are not allowed in the study until completion of 
latent TB treatment is documented.
12) Able and willing to sign the informed consent as approved by IRB / IEC. Written consent 
must be provided before initiating any Screening evaluations. Subjects must have read and 
understood the informed consent form (ICF), must fully understand the requirements of the 
study, and must be willing to comply with all study visits and assessments. Subjects who 
cannot read or understand the ICF may not be enrolled by a guardian or any other individual.
13) Able and willing to perform SC self-injections or have a caregiver able, willing, and 
available to administer the injections
14) Subjects receiving non-prohibited medication for any reason should be on a stable dose 
(defined as no change in prescription and stable per investigator judgment) prior to the first 
administration of study drug on Day 1
15) A negative serum pregnancy test result at the Screening Visit and negative urine pregnancy 
test result at the Day 1 Visit are required for female subjects of child bearing potential 
(as defined in Appendix 3)
16) Male subjects and female subjects of childbearing potential who engage in heterosexual 
intercourse must agree to use protocol specified method(s) of contraception as described in 
Appendix 3.
17) Lactating females must agree to discontinue nursing before the study drug is administered
4.3.
Exclusion Criteria
Subjects who meet any of the following exclusion criteria are not to be enrolled in this study.
1) Known hypersensitivity to the study drug, the metabolites, or formulation excipients
2) Prior PsA or psoriasis treatment with a bioDMARD 
3) Prior exposure to a JAK inhibitor >2 doses


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4) Corticosteroid use as follows:
a) Intra-articular corticosteroids ≤8 weeks of Day 1
b) Parenteral corticosteroids ≤2 weeks of Day 1
5) Use of any of the following treatments ≤4 weeks of Day 1:
a) Intra-articular injection of hyaluronate therapies
b) Oral retinoids (including tazarotene) 
c) Phototherapy (UVA or UVB) with or without psoralens or self-treatment with sunbathing 
or tanning beds
d) Potent P-glycoprotein (P-gp) inducers (e.g. carbamazepine, clotrimazole, dexamethasone, 
phenothiazine, phenytoin, retinoic acid, rifampin, St. John’s wort and venlafaxine)
e) Oral or injectable gold
f)
D-penicillamine
g) Cytotoxic agents including chlorambucil, cyclophosphamide, nitrogen mustard, or other 
alkylating agents
6) Any moderately to severely active musculoskeletal or skin disorder other than PsA or plaque 
psoriasis that would interfere with assessment of study parameters, as per judgment of 
investigator
NOTE: Prior history of reactive arthritis or axial spondyloarthritis is permitted if there is 
documentation of change in diagnosis to PsA or an additional diagnosis of PsA
7) Any history of an inflammatory arthropathy with onset before age 16 years old
8) Active autoimmune disease that would interfere with assessment of study parameters or 
increase risk to the subject by participating in the study, (e.g. uveitis, inflammatory bowel 
disease, uncontrolled thyroiditis, systemic vasculitis, transverse myelitis), per judgement of 
investigator
9) Presence of any extra-articular manifestations typically associated with RA, such as 
rheumatoid nodules, rheumatoid lung, or other signs / symptoms, as per judgement of 
investigator
10) Have undergone surgical treatments for PsA, including synovectomy or arthroplasty 
in >4 joints and / or ≤12 weeks prior to Day 1
11) History of major surgery (requiring regional block or general anesthesia) ≤3 months prior to 
Screening or planned major surgery during the study


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12) Administration of a live / attenuated vaccine ≤30 days prior to Day 1, or planned during the 
study
13) Participation in any clinical study of an investigational drug / device ≤4 weeks or 5 half-lives 
prior to Screening, whichever is longer. Exposure to investigational biologics must be 
discussed with the Sponsor with written approval.
14) History of or current moderate to severe congestive heart failure (New York Heart 
Association [NYHA] class III or IV), or within the last 6 months, a cerebrovascular accident, 
myocardial infarction, unstable angina, unstable arrhythmia, new or significant ECG finding 
at Screening, or any other cardiovascular condition which, in the opinion of the investigator, 
would put the subject at risk by participation in the study
15) History of malignancy ≤5 years prior to Screening (except for adequately treated basal cell 
carcinoma or non-metastatic squamous cell carcinoma of the skin or cervical carcinoma in 
situ, with no evidence of recurrence)
16) History of lymphoproliferative disease or current lymphoproliferative disease
17) History of organ or bone marrow transplant
18) History of gastrointestinal perforation
19) Positive serology for human immunodeficiency virus (HIV) 1 or 2
20) Evidence of active HCV infection. Subjects with positive HCV Antibody (Ab) at Screening, 
require reflex testing for HCV RNA. Subjects with positive HCV RNA viral load (VL) at 
Screening will be excluded. Subjects with positive HCV Ab, but negative HCV RNA VL are 
eligible per investigator judgment, but require ongoing monitoring as outlined in the Study 
Procedures Table (Appendix 2).
21) Evidence of active HBV infection. Subjects with positive HBV surface antigen (HBsAg) at 
Screening are excluded from the study. Subjects with positive HBV core Ab and negative 
HBsAg, require reflex testing for HBV DNA. Subjects with positive HBV DNA at Screening 
will be excluded. Subjects with positive HBV core Ab, and negative HBV DNA are eligible 
per investigator judgment, but may require prophylactic treatment in accordance with HBV 
treatment guidelines / local standard of care and require ongoing monitoring with blood tests 
for HBV DNA as outlined in the Study Procedures Table (Appendix 2).
22) History of opportunistic infection, or immunodeficiency syndrome, which would put the 
subject at risk, as per investigator judgment
23) Active infection that is clinically significant, as per judgment of the investigator, or any 
infection requiring hospitalization or treatment with intravenous anti-infectives ≤60 days of 
Screening; or any infection requiring oral anti-infective therapy ≤2 weeks of Day 1
24) Currently on any therapy for chronic infection (such as pneumocystis, cytomegalovirus, 
herpes zoster, and atypical mycobacteria)


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25) History of disseminated staphylococcus aureus or disseminated herpes simplex infection
26) History of symptomatic herpes zoster infection ≤12 weeks prior to Screening or have history 
of disseminated / complicated herpes zoster infection (multi-dermatomal involvement, 
ophthalmic zoster, central nervous system involvement or postherpetic neuralgia)
27) History of an infected joint prosthesis or other implanted device with retention of the 
prosthesis or device in situ
28) Current tobacco, alcohol, or substance abuse, per investigator judgement
29) Any known condition or contraindication as addressed in the local labeling for adalimumab 
that would preclude the subject from participating in this study
30) Active fibromyalgia or other disorder that based on the investigator’s opinion would make it 
difficult to appropriately assess PsA activity for the purposes of this study
31) Any chronic, uncontrolled medical condition, which would put the subject at increased risk 
during study participation including but not limited to: diabetes, hypertension, morbid 
obesity, thyroid, adrenal, pulmonary, hepatic, renal, neurological and / or psychiatric disease 
or other disease of concern, or circumstances which may make a subject unlikely or unable to 
complete or comply with study procedures and requirements, as per investigator judgement
32) Ongoing suicidal ideation or history of suicide attempt ≤20 years of Screening
33) Significant blood loss (>450 mL) or transfusion of any blood product ≤12 weeks prior to 
Day 1
34) Central laboratory tests at Screening that meet any of the criteria below:
a) Hemoglobin <8.0g / dL (SI: <80 g / L)
b) White blood cells <3.0 x 103 cells / mm3 (SI: <3.0 x 109 cells / L)
c) Neutrophils <1.5 x 103 cells / mm3 (SI: <1.5 x 109 cells / L)
d) Lymphocytes <0.5 x 103 cells / mm3 (SI: <0.5 x 109 cells / L)
e) Platelets <100 x 103 cells / mm3 (SI: <100 x 109 cells / L)
f)
ALT or AST ≥1.5x ULN
g) Total bilirubin level ≥1.5x ULN unless the subject has been diagnosed with Gilbert’s 
disease and this is clearly documented
h) Estimated creatinine clearance <40 mL/min based on the Cockroft Gault formula
NOTE: Before subject is considered a screen-failure, out of range lab values may be rechecked 
one time after consultation with the Sponsor or designee. Written approval must be obtained.
35) Subject is unwilling or unable to follow protocol requirements


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4.4.
MRI Investigation Eligibility Criteria 
4.4.1.
MRI Inclusion Criteria:
1) Subject must fulfill criteria for entry to the Main Study
2) Subject must have PsA joint involvement at a minimum in one hand / wrist as confirmed by 
the investigator at Screening. The same hand / wrist (R or L) should be imaged at all 
subsequent MRIs, regardless of PsA activity
3) Subject’s baseline MRI must fulfill at least one of the below criteria by central reading:
a) Definitive intra-articular MRI synovitis (PsAMRIS Grade ≥2 in any applicable hand or 
wrist joint, or PsAMRIS Grade 1 in ≥2 applicable joints)
OR
b) Definitive MRI osteitis in any applicable bone
4) An acceptable baseline MRI read and approved by central imaging, on or before the end of 
the Screening period
4.4.2.
MRI Exclusion Criteria
Subjects may still participate in the Main Study / LTE if ineligible for the MRI investigation. 
Reasons for ineligibility may include, but are not limited to:
1) Inability or medical contraindication for an MRI examination (e.g. presence of a pacemaker, 
defibrillator, or other contraindicated implanted metallic device, such as anterior interbody 
cages, aneurysm clip or pedicle screws, severe claustrophobia or weight >350 lbs./158 kg)
2) Metallic fragments embedded anywhere in the body OR pigment-containing tattoos in the 
area of examination
3) Known or potential risk of adverse reaction to gadolinium-based contrast agents, including 
but not limited to, allergy or compromised renal function, per investigator judgment
4) Very difficult peripheral intravascular access
4.5.
Screen Failures
Subjects who do not enter the study due to administrative reasons (for example, exceeding the
screening window due to issues with appointment scheduling or delays in obtaining results of 
laboratory data) may be rescreened one time.


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Subjects who are permitted to rescreen will receive a new screening number and must repeat all 
screening assessments including the informed consent. Rescreening should not be used to 
recheck a subject who is likely unsuitable for the study, for example, to check whether their 
chronically abnormal laboratory test is closer to normal range.
Subjects who do not meet the inclusion / exclusion criteria for entry into the MRI investigation 
(“MRI screen failures”), should forgo the MRI investigation and continue participation in the 
Main Study.


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5. 
STUDY DRUG 
5.1. 
Randomization, Blinding and Treatment Codes 
Final 
Amendment2 
An Interactive Voice / Web Response System (IXRS) will be used to manage subject 
randomization and treatment assignments. It is the responsibility of the investigator to ensure that 
the subject is eligible for the study prior to enrolhnent. Randomization scheme for each Main 
Study's transition to the LTE is outlined in Section 3.2. Study drug assigmnents either at 
Baseline or at LTE will be maintained in a blinded fashion within the IXRS. 
Subjects and Investigators will be kept blinded to the results of the CRP test at all visits. Sponsor 
will be blinded to CRP results in the Main Study only, except the Day 1 Visit. T and B 
lymphocyte and natural killer (TBNK) results will be blinded to subjects and Investigators at all 
visits. 
Individuals in Clinical Packaging and 
Labeling or Clinical Supply Management who have an Unblinded Inventory Manager role in the 
IXRS system for purposes of study drug inventory management, and individuals in 
Phannacovigilance and Epidemiology (PYE) responsible for safety signal detection, and / or 
expedited reporting of suspected unexpected serious adverse reactions (SUSARs) to regulatory 
authorities may be m1blinded to individual case data and / or group level smmnaries. Contract 
research organization (CRO) biostatisticians and progra1mners will be unblinded for the DMC 
data reviews. 
5.1.1. 
Procedures for Breaking Treatment Codes 
In the event of a medical emergency where breaking the blind is required to provide medical care 
to the subject, the investigator may obtain treatment assigmnent directly from the IXRS system 
for that subject. Gilead reco1mnends, but does not require, that the investigator contact the Gilead 
Medical Monitor or designee before breaking the blind. Treatment assigmnent should remain 
blinded unless that knowledge is necessary to detennine subject emergency medical care. The 
rationale for unblinding must be clearly explained in source documentation and on the electronic 
case report fonn ( eCRF), along with the date on which the treatment assigmnent was unblinded. 
The investigator is requested to contact the Gilead Medical Monitor or designee promptly in case 
of any treatment unblinding. 
If a subject's treatment assigmnent is disclosed to the investigator due to a medical emergency, 
the subject will have study treatment discontinued. 
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5.2.
Description and Handling of Filgotinib and PTM Filgotinib
5.2.1.
Formulation of Filgotinib and PTM Filgotinib
Filgotinib is provided as 100 mg and 200 mg strength tablets. Filgotinib tablets, 100 mg and 
200 mg, are beige, debossed with “GSI” on one side and “100” or “200” on the other, 
capsule-shaped, biconvex, film-coated tablets for clinical use. Each tablet contains the equivalent 
of 100 mg or 200 mg filgotinib free base in the form of filgotinib maleate. In addition to the 
active ingredient, filgotinib tablets contain the following inactive ingredients: microcrystalline 
cellulose, lactose monohydrate, fumaric acid, pregelatinized starch, silicon dioxide, magnesium 
stearate, macrogol / polyethylene glycol (PEG) 3350, polyvinyl alcohol, talc, titanium dioxide, 
iron oxide yellow, and iron oxide red.
PTM filgotinib tablets, 100 mg and 200 mg, are identical in appearance to the respective active 
tablets. PTM filgotinib tablets contain the following inactive ingredients: microcrystalline 
cellulose, lactose monohydrate, croscarmellose sodium, magnesium stearate, 
macrogol / PEG 3350, polyvinyl alcohol, talc, titanium dioxide, iron oxide yellow, and iron 
oxide red. For the purpose of the LTE, PTM filgotinib tablets will only be utilized for the 
maintenance of the Main Study’s treatment assignment blind, and not as a comparator treatment 
to active filgotinib.
5.2.2.
Packaging and Labeling of Filgotinib and PTM Filgotinib
Filgotinib tablets, 100 mg and 200 mg, and PTM filgotinib tablets, 100 mg and 200 mg, are 
packaged in white, high density polyethylene (HDPE) bottles. Each bottle contains 30 tablets, 
silica gel desiccant and polyester packing material. Each bottle is enclosed with a white,
continuous thread, child-resistant polypropylene screw cap fitted with an induction-sealed, 
aluminum-faced liner.
Sufficient quantities of filgotinib tablets, 100 mg and 200 mg, and PTM filgotinib tablets to 
complete the entire study will be shipped to the investigator or qualified designee from the 
Gilead Supply Management Team (or its designee).
Study drugs to be distributed to participating sites shall be labeled to meet applicable 
requirements of the U.S. FDA, the EU Guideline to Good Manufacturing Practice – Annex 13 
(Investigational Medicinal Products), the Ministerial Ordinance on Good Clinical Practice for
Drugs in Japan, and / or other local regulations, as applicable.
5.2.3.
Storage and Handling of Filgotinib and PTM Filgotinib
Filgotinib tablets and PTM filgotinib tablets should be stored at controlled room temperature of 
25°C (77°F); excursions are permitted between 15°C and 30°C (59°F to 86°F). Storage 
conditions are specified on the label.


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Until dispensed to the subjects, all drug products should be stored in a securely locked area, 
accessible only to authorized site personnel. To ensure the stability of the study drug and to 
ensure proper product identification, the drug product should not be stored in a container other 
than the container in which they are supplied. Consideration should be given to handling, 
preparation, and disposal through measures that minimize drug contact with the body. 
Appropriate precautions should be followed to avoid direct eye contact or exposure when 
handling.
5.2.4.
Dosage and Administration of Filgotinib and PTM Filgotinib
Filgotinib tablets, 100 mg or PTM and 200 mg or PTM will be administered once daily with or 
without food. Each subject should be given instructions to maintain approximately the same 
daily time of administration to ensure similar dosing interval is maintained between study drug 
doses.
For missed dose(s) of study medication, subjects should be instructed to take the missed dose(s) 
of study medication as soon as possible during the same day. If the missed dose is not taken on 
the original day, subjects should be cautioned not to double the next dose with the missed dose of 
study drug under any circumstances. In those cases, the missed dose should be returned to the 
study drug bottle.
5.3.
Description and Handling of Adalimumab and PTM Adalimumab
5.3.1.
Formulation of Adalimumab and PTM Adalimumab
Adalimumab is commercially sourced. Information regarding the formulation can be found in the 
current prescribing information.
PTM adalimumab will be manufactured by Gilead Sciences, Inc. (GSI) to match the presentation 
of adalimumab. It will be visually identical to the adalimumab, but will contain no active 
ingredient. PTM adalimumab for SC injection is formulated as a sterile, aqueous buffered 
solution in a single-use prefilled syringe. The buffered solution contains sucrose, acetic acid, and 
sodium acetate at pH 5.0.
5.3.2.
Packaging and Labeling of Adalimumab and PTM Adalimumab
Adalimumab and PTM for SC injection will be supplied in clear, single-use prefilled syringe. 
Each syringe delivers 40 mg of drug product or matching placebo.
Study medication to be distributed to participating sites shall be labeled to meet applicable 
requirements of the US FDA, EU Guideline to Good Manufacturing Practice – Annex 13 
(Investigational Medicinal Products), the Ministerial Ordinance on Good Clinical Practice for
Drugs in Japan, and / or other local regulations, as applicable.


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5.3.3.
Storage and Handling of Adalimumab and PTM Adalimumab
Adalimumab and PTM should be stored under refrigeration between 2°C to 8°C (36°F to 46°F), 
protected from light and should not be frozen. Storage conditions are specified on the label.
Until dispensed to the subjects, all drug products should be stored in a securely locked area, 
accessible only to authorized site personnel. To ensure the stability of the study drug and to 
ensure proper product identification, the drug product should not be stored in a container other 
than the container in which they are supplied. Consideration should be given to handling, 
preparation, and disposal through measures that minimize drug contact with the body. 
Appropriate precautions should be followed to avoid direct eye contact or exposure when 
handling.
5.3.4.
Dosage and Administration of Adalimumab and PTM Adalimumab
Adalimumab or PTM adalimumab will be self-administered by the subject or caregiver as 
specified in study procedures and instructions provided to the subject. Subject or caregivers will 
be instructed to subcutaneously administer adalimumab or PTM adalimumab study medication 
once every other week according to the instructions provided to them. On weeks when study 
visits are scheduled, the injection should be planned to occur as outlined in the Priority of 
Assessments (Section 6.6.1). 
At the investigational site, all adalimumab supplies and PTM adalimumab must be handled and 
stored safely and properly, and kept in a secured location to which only the investigator and 
authorized staff have access.
5.4.
Prior and Concomitant Medications
Concomitant therapies for treatment of pre-existing conditions may be continued during the 
study provided they are in accordance with the inclusion and exclusion criteria (Section 4), and 
the permitted and prohibited concomitant medication instructions throughout Section 5.4. These 
medications should be continued without variation of dose or regimen during the study, as much 
as possible.
All non-PsA medication(s) used within 30 days of consent, including any changes, are to be 
documented in the eCRF. All prior medication(s) used in the treatment for PsA will be 
documented in the eCRF.
At each study visit, the site will capture any and all medications taken by the subject since the
last visit or during the visit (as applicable). Concomitant medications include prescription
medications, non-prescription medications, naturopathic therapies, dietary supplements, vitamins
and minerals.
In case new non-prohibited therapies need to be administered during the study, the risk / benefit
to the subject should be carefully assessed and consideration given to the timing of any necessary
introduction of new medications.


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5.4.1.
Concomitant Medications: PsA Related
Permitted concomitant medications for PsA should be kept stable as much as possible throughout 
the study and include:

NSAIDs, at a stable dose and regimen, through the Week 16 Visit, as much as possible. On 
the day of any study visit, NSAIDs should be held 12 hours before the visit until all 
scheduled assessments have been completed for that visit day.

Analgesics, including opioids and other non-NSAID based therapies, at a stable dose and 
regimen, as much as possible. On the day of any study visit, analgesics should be held 
12 hours before the visit until all scheduled assessments have been completed for that day.

Oral prednisone ≤10 mg daily (or equivalent), at a stable dose and regimen, through the
Week 16 Visit. If there is a need for the use of additional corticosteroids (oral, parenteral, 
inhaled or other) for the treatment of an AE, it should be discussed with the Gilead Medical 
Monitor or designee in advance, as much as possible, as well as the possible discontinuation 
of study drug and / or the subject from the study. The AE and medications administered will
be documented in the eCRF. See Section 5.4.1.2 for additional guidance on special 
circumstances for corticosteroids.

Topical therapies for psoriasis (e.g. topical corticosteroids, coal tar, salicylic acid, vitamin D 
analogs, retinoids, anthralin, topical calcineurin inhibitors such as tacrolimus) at a stable dose 
and regimen through the Week 16 Visit.

csDMARDs (maximum of 2 can be taken together during the study):
a) MTX oral or SC up to 25 mg / week (must include concomitant use of a folic acid 
supplementation as per local standard of care / investigator judgment). Dose should be 
stable through the Week 16 Visit.
NOTE: MTX may not be combined with leflunomide.
b) Leflunomide up to 20 mg once daily orally Dose should be stable through the Week 16
Visit.
NOTE: Leflunomide may not be combined with MTX.
c) Sulfasalazine up to 3 g daily orally. Dose should be stable through the Week 16 Visit.
d) Hydroxychloroquine up to 400 mg daily or chloroquine up to 250 mg daily. Dose should 
be stable through the Week 16 Visit.
e) Apremilast up to 30 mg twice daily orally. Dose should be stable through the Week 16
Visit.


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Dose adjustments for management of toxicity of the above medications are allowed and should 
be documented, along with documentation of the AE which led to the change in the medication.
After the Week 16 Visit, subject's dose of concomitant medications for PsA can be reduced or 
tapered based on investigator judgement. The dose may be adjusted back up as needed, but 
should not exceed the stable dose identified on Day 1.
Please note that certain PsA concomitant medications such as antimalarial drugs, systemic 
corticosteroids, and NSAIDs, as well as certain non-PsA-related medications such as beta 
blockers, lithium, and ACE inhibitors, can cause dermatitis or exacerbate psoriasis.
5.4.1.1.
PsA Rescue Therapy
Investigators should perform an ongoing assessment of a subject’s need for rescue therapy 
beginning at the Week 16 Visit through the completion of the study. Sites will be assisted with 
this by receiving a one-time alert at the Week 16 Visit for subjects with <20% improvement from 
Day 1 in the TJC68 or SJC66 (these subjects are referred to as inadequate responders). At that 
time, it will be required to modify the subject’s concomitant medication(s) by adjusting the dose 
of existing medication(s) and / or introducing new medication(s) based on investigator 
judgement along with consideration of the subject’s medical history (e.g. comorbidities, history 
of concomitant medications, etc.). After the Week 16 Visit investigators will not receive an alert 
for subjects with <20% improvement; however, clinical judgement should be used to decide if 
the subject is not clinically improving and requires rescue therapy. The following medications 
are recommended as rescue therapy options to add or modify after Week 16: NSAIDs, opiate 
analgesics, csDMARDs, corticosteroids, and bioDMARDs. Subjects must discontinue study at 
time of bioDMARD initiation.
Starting at the Week 24 Visit, subjects who have <10% improvement from Day 1 in the TJC68
or SJC66 at two consecutive visits despite stable background PsA therapy should discontinue 
both study drug and study and adjust any PsA treatment as deemed appropriate by the 
investigator. Sites will be assisted with this by receiving a discontinuation of study alert when 
subjects reach this threshold at any time from the Week 24 Visit through the end of the study.  
In cases where a subject has had recent modification of PsA therapy requiring time for further 
assessment, the investigator should use clinical judgement to decide if subjects should continue 
study drug and study despite receiving the discontinuation alert.
Subjects who discontinue study drug at any point during the LTE should also exit the study.
5.4.1.2.
Special Circumstances for Corticosteroids, Hyaluronate Therapy, and Biologics
At any time during the study if there is a need for the use of additional corticosteroids 
(oral, parenteral, inhaled or other) for the treatment of an AE (e.g. asthma exacerbation, allergy,
or anaphylaxis reaction, etc.), it should be discussed with the Gilead Medical Monitor or its 
designee in advance, as much as possible, as well as the possible discontinuation of study drug 
and / or the study. The AE and medications administered will be documented in the eCRF.


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During the LTE subjects may receive intra-articular corticosteroids or hyaluronate therapy for 
treatment of PsA if needed. The dose of corticosteroid injected should not exceed the equivalent 
dose of triamcinolone 80 mg suspension. For the analysis of the SJC66 and TJC68, these joints 
will be considered “not assessable” for 3 months from the time of the intra-articular injection and 
should be documented.
Concomitant biologics not given for the treatment of an inflammatory arthropathy (i.e. given for 
osteoporosis) may be allowable after written approval from the Gilead Medical Monitor or 
designee.
5.4.2.
Concomitant Medications: Non-PsA Related
Non-PsA related therapy such as hormone replacement therapy, thyroid replacement, and other 
chronic therapies (such as those for well-controlled diabetes or hypertension) are permitted 
during the study, and should be kept at a stable dose and regimen, as much as possible.
Vitamin, mineral, or herbal supplementations are permitted during the study per judgment of
investigator, and should be kept at a stable dose and regimen, as much as possible.
Female subjects of childbearing potential must agree to use highly effective birth-control 
methods as outlined in Appendix 3. The use of contraceptives will be recorded in the 
Concomitant Therapy section of the eCRF. Applicable procedures and treatment guidance based 
on package inserts will be followed.
5.4.3.
Prohibited Concomitant Medications
Prohibited concomitant medications at the time of randomization, with applicable washout 
periods, are included in the Exclusion Criteria (Section 4.3).
Prohibited concomitant medications during the course of the study are as follows:

Throughout the entire study unless required for rescue therapy after the Week 16 Visit:
Intra-articular or parenteral corticosteroids
Intra-articular hyaluronate injections
Small molecule immunomodulators that were not already started at the time of study 
enrollment (i.e. subject cannot start methotrexate, hydroxychloroquine, etc., as a new 
concomitant medication after Day 1unless required for rescue therapy after the Week 16 
Visit)
Ultraviolet light therapy
BioDMARDs (e.g. etanercept, golimumab, abatacept, secukinumab, etc.) If required for 
rescue therapy per investigator judgment, subjects must discontinue study at time of 
bioDMARD initiation.
B-cell depleting agents (e.g. rituximab, etc.) If required for rescue therapy per 
investigator judgment, subjects must discontinue study at time of B-cell depleting agent 
initiation.


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
Throughout the entire study:
JAK inhibitors (e.g. tofacitinib, baricitinib, etc.)
Potent Pg-p inducers (e.g. rifampin, phenytoin, carbamazepine, and St. John’s wort)
Oral or injectable gold
D penicillamine
Any cytotoxic agent, including chlorambucil, cyclophosphamide, nitrogen mustard, and 
other alkylating agents
Investigational drugs or devices
5.4.4.
Vaccine Guidelines
Prior to study participation, it is recommended that the subject’s vaccinations be brought up to 
date according to local vaccination standards. The varicella vaccine is of particular importance 
for immunocompromised patients.
Live or attenuated vaccines (including, but not limited to varicella and inhaled flu vaccine) are 
prohibited ≤30 days of the Day 1 Visit, throughout the study, and for 4 weeks after the last dose 
of study drug.
Subjects should be advised to avoid routine household contact with persons vaccinated with 
live / attenuated vaccine components. A study subject’s exposure to household contacts should 
be avoided for the below stated time periods:

Varicella or attenuated typhoid fever vaccination – avoid contact for 4 weeks following 
vaccination

Oral polio vaccination – avoid contact for 6 weeks following vaccination

Attenuated rotavirus vaccine – avoid contact for 10 days following vaccination

Inhaled flu vaccine – avoid contact for 1 week following vaccination
Inactivated vaccines (such as inactivated flu vaccines) should be administered according to local 
vaccination standards whenever medically appropriate; however, there are no available data on 
the concurrent use of filgotinib and its impact on immune responses following vaccination.
5.5.
Accountability for Study Drugs
The investigator is responsible for ensuring adequate accountability of all used and unused study 
drugs. This includes acknowledgement of receipt of each shipment of study drugs (quantity and 
condition). All used and unused study drugs dispensed to subjects must be returned to the site.


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Filgotinib, adalimumab, and PTMs accountability records will be provided to each study site to:

Record the date received and quantity of study drugs

Record the date, subject number, subject initials, the study drug number dispensed

Record the date, quantity of used and unused study drugs returned, along with the initials of 
the person recording the information

Dispensing records will include the initials of the person dispensing the study drug or 
supplies
5.5.1.
Study Drug Return or Disposal
At study initiation, the monitor will evaluate the site’s standard operating procedure for study 
drug disposal / destruction in order to ensure that it complies with Gilead’s requirements. Study 
drug may be returned or destroyed on an ongoing basis during the study, if appropriate. At the 
end of the study, following final drug inventory reconciliation by the monitor, the study site will 
dispose of and / or destroy all unused study drug supplies, including empty containers, according 
to these procedures. If the site cannot meet Gilead’s requirements for disposal, arrangements will 
be made between the site and Gilead or designee for destruction or return of unused study drug
supplies.
All drug supplies and associated documentation will be periodically reviewed and verified by the 
study monitor over the course of the study.
For additional information about study drug accountability and return, refer to Section 9.1.8


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6.
STUDY PROCEDURES
The study procedures to be conducted for each subject enrolled in the study are presented in 
tabular form in Appendix 2. Assessments that need specific attention are described in the text 
that follows.
The investigator must document any deviation from protocol procedures and notify the Sponsor 
or designee.
6.1.
Part 1 – Main Study (Screening through Week 16 Visit)
6.1.1.
Screening Visit
Entry into screening does not guarantee enrollment into the study. In order to manage the total 
trial enrollment, Gilead, at its sole discretion, may suspend screening and / or enrollment at any 
site or trial-wide at any time.
Subjects will be screened ≤28 days before randomization to determine eligibility for participation 
in the study. Study assessments will be completed as specified in the Study Procedures 
Table (Appendix 2). Prior to any assessments being performed, a written consent must be 
obtained.
Subjects meeting all of the inclusion criteria and none of the exclusion criteria will return to the 
clinic ≤28 days after screening for randomization into the study.
6.1.1.1.
MRI Investigation
Subjects meeting all of the Main Study inclusion criteria and none of the Main Study exclusion 
criteria may be entered into an MRI investigation if all MRI inclusion and none of the MRI 
exclusion criteria are met.
Subjects participating in the MRI investigation must have an acceptable baseline MRI as per the 
central review. Subject’s MRIs should only be taken after all other eligibility criteria within the 
main study have been met. To allow for scheduling and reading of images, the screening period 
may be extended to 42 days, in these cases only. A single repeat MRI may be done if determined 
required by central review and must be completed before the Day 1 Visit. See Section 4.5 for 
additional information on MRI screen failures.
6.1.2.
Day 1 Visit
Study assessments will be completed as specified in the Study Procedures Table (Appendix 2). 
At the end of the visit, subjects will be randomized. Refer to Appendix 7 for how days of 
treatment are numbered.


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Subjects will be randomly allocated to a dosing group according to a pre-specified randomization 
scheme prepared by an independent statistician. Once confirmed eligible for the study, subjects 
will be randomized using a computerized IXRS system. Randomization will be stratified by 
geographic region, concurrent use of csDMARDs and / or apremilast at randomization (yes or 
no).
For each subject at each visit, the clinic will contact the IXRS system and for the appropriate kit 
number to be dispensed. The kit will contain the relevant study drugs for the period until the next 
dispensation visit.
Female subjects of child bearing potential will be provided at-home pregnancy tests for use at the 
Safety Follow-up Visit or as needed.
6.1.3.
Week 2 Visit through Week 16 Visit
Study assessments will be completed as specified in the Study Procedures Table (Appendix 2).
For the first 16 weeks of study participation, subjects who temporarily interrupt or permanently 
discontinue blinded study drug for any reason are to continue with study visits and assessments 
through the Week 16 Visit, unless the subject withdraws consent, is lost to follow-up, and / or 
continuation in the study is medically contraindicated, per investigator’s judgment. The Week 16
Visit will be their last in-clinic visit.
6.2.
Part 2 - LTE (After the Week 16 Visit and up to 2 years)
After completion of the Main Study, subjects who have not permanently discontinued study drug 
will continue on to the LTE as follows:
Those who were assigned to the filgotinib groups will continue on the same study drug 
assignments.
Those who were assigned to the placebo or active comparator groups will be reassigned 1:1 in a 
blinded fashion to filgotinib 100 mg or 200 mg once daily.
Study assessments will be completed as specified in the Study Procedures Table (Appendix 2).
6.3.
Early Termination (ET) Visit
If a subject discontinues the study early either during the Main Study or during the LTE, every 
attempt should be made to perform the required study-related ET procedures and Safety 
Follow-up Visit procedures as specified in the Study Procedures Table (Appendix 2).


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6.3.1.
Main Study Early Termination Visit
Subjects who permanently discontinue study drug prior to or at the Week 16 Visit and exit the 
study at the Week 16 Visit will need to perform a Main Study ET Visit in lieu of the Week 16
Visit. Subjects who permanently discontinue study drug and permanently discontinue study prior 
to the Week 16 Visit should perform a Main Study ET Visit ≤7 days of study discontinuation.
6.3.2.
LTE Early Termination Visit
Subjects who permanently discontinue study drug during the LTE should perform an LTE ET
Visit ≤7 days of study drug discontinuation.
6.4.
Completion Visit
At the Week 120 Visit (~2.25 years), subjects will have their last in-clinic visit and will complete
study assessments as specified in the Study Procedures Table (Appendix 2).
6.5.
Safety Follow-up Visit
The Safety Follow-up Visit will be performed approximately 4 weeks after a subject’s last 
in-clinic visit in either the Main Study or the LTE as specified in the Study Procedures Table 
(Appendix 2). This visit should be done by phone call unless otherwise required by region.
Subjects in Europe will have additional Safety Follow-up Visits. These visits will occur 8, 12, 
and 16 weeks after their last SC injection of study drug and should also be done by phone call 
unless otherwise required by region. If the subject’s last study visit is greater than or equal to 
16 weeks from their last SC injection, the additional Safety Follow-up Visits will not be 
required.
6.6.
Study Assessments
Study Assessments will be performed at the time points indicated in the Study Procedures 
Table (Appendix 2).
6.6.1.
Assessment Order
The recommended order of study procedures is as follows: 
1) Patient Reported Outcomes (PROs)
NOTE: It is recommended that the PROs are performed at the beginning of each visit prior to 
any other visit-related procedures, other than signing of informed consent.
2) Clinical assessments (e.g. physical exam, physician reported outcome measures, recording of 
history, AEs, concomitant medications, etc.)
3) Laboratory sample collection, imaging and biopsy assessments, as applicable
4) Study drug dosing


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6.6.2.
Demographics, Medical History, and Physical Exams
At the Screening Visit, subject’s demographics (year of birth, age, sex, race, ethnicity, etc.), 
baseline disease characteristics (current medical conditions, spondylitis, history of extra-articular 
involvement such as uveitis, psoriasis, inflammatory bowel disease (IBD), dactylitis, enthesitis, 
etc.), PsA diagnosis, prior PsA treatment(s) and medical history will be collected. This will 
include but is not limited smoking status, average weekly alcohol consumption, any other 
chronic medical conditions, and prior surgeries.
Complete physical examinations and symptom-driven physical examinations will be performed 
at the time points indicated in the Study Procedures Table (Appendix 2). A complete physical 
examination should include source documentation of general appearance, and the following body 
systems: Head, neck and thyroid; eyes, ears, nose, throat, mouth and tongue; chest (excluding 
breasts); respiratory; cardiovascular; lymph nodes; abdomen; skin, hair, nails; musculoskeletal; 
and neurological. Any changes from Baseline will be recorded. Height will be measured at the 
Screening Visit only.
6.6.3.
Efficacy
6.6.3.1.
Patient Reported Outcomes
Comprehensive descriptions and instructions for each PRO are provided in the electronic clinical 
outcomes assessments materials. Examples can be found in Appendix 9. - Appendix 26.
PROs collected in this study will include:

HAQ-DI: Health Assessment Questionnaire – Disability Index 

FACIT-Fatigue: Functional Assessment of Chronic Illness Therapy – Fatigue Scale

SF-36v2: 36 - item Short - Form Health Survey Version 2

PsAID-12: 12-item Psoriatic Arthritis Impact of Disease

PGADA: Patient’s Global Assessment of Disease Activity

PGAPI: Patient’s Global Assessment of Psoriatic Arthritis Pain Intensity
CCI
CCI
CCI
CCI
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6.6.3.2.
Clinical Reported Outcome Measurements
Comprehensive descriptions and instructions for each clinical assessment are provided in the 
electronic clinical outcomes assessments materials. Examples can be found in 
Appendix 9. - Appendix 26
Physician (or site staff designee) reported outcome measurements collected in this study include:

PASI including BSA: Psoriasis Area and Severity Index including Body Surface Area

mNAPSI: Modified Nail Psoriasis Severity Index

PhGAP: Physician’s Global Assessment of Psoriasis 

SPARCC Enthesitis Index and LEI: Spondyloarthritis Research Consortium of Canada 
Enthesitis Index and Leeds Enthesitis Index

SJC66 / TJC68: Swollen and Tender Joint Count

LDI: Leeds Dactylitis Index

PhGADA: Physician’s Global Assessment of Disease Activity
6.6.3.3.
Independent Assessor
Assessment of tender and swollen joints, dactylitis, enthesitis, and psoriasis of the skin and nails 
will take place at the time points indicated in the Study Procedures Table (Appendix 2). The 
clinical assessment forms are provided in Appendix 20, Appendix 21, Appendix 23, 
Appendix 24, and Appendix 25.
An independent clinical assessor with adequate training including completion of the required 
training provided by the Sponsor, and experience in performing these assessments will be 
designated at each study site to perform all relevant assessments including SJC66 / TJC68, 
SPARCC Enthesitis Index and LEI, LDI, PASI including BSA, and mNAPSI should be blinded 
to the other study assessments performed on that day. The assessor should preferably be a 
rheumatologist; however, if a rheumatologist is not available, it should be a health care worker 
who has completed the required training provided by the Sponsor and has experience in 
performing these assessments. The assessor should remain the same throughout the study per 
subject, as much as possible. It is required that the designated assessor identify an appropriate 
back up assessor to provide coverage if the designated assessor is absent.


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6.6.4.1. 
Safety Assessments 
Vital Signs and Weight 
Final 
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Vital signs and weight will be perfonned at the time points indicated in the Study Procedures 
Table (Appendix 2). 
Vital signs should be taken after the subject has been resting for 5 minutes and will include heart 
rate, respiratory rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), and body 
temperature. Weight will be measured without shoes. 
6.6.4.2. 
12-lead Electrocardiogram 
A resting 12-lead ECG will be perfonned at the Screening Visit only. 
The ECG should be obtained after the subject has been resting in the supine position for 5 min 
and will include heart rate (HR), QRS, uncorrected QT, morphology, and rhythm analysis. ECGs 
will be interpreted by the investigator ( or qualified designee) for clinical significance and results 
will be entered into the eCRF. 
6.6.4.3. 
Pregnancy Test 
For females of childbearing potential only, pregnancy tests will be perfonned at the time points 
indicated in the Study Procedures Table (Appendix 2). 
For eligibility, a serum pregnancy test will be perfonned at the Screening Visit and a urine 
pregnancy test will be perfonned at the Day 1 Visit. Urine pregnancy tests will be perfonned at 
all other visits. Subjects will be provided an at-home pregnancy test for use during the LTE, at 
the Safety Follow-up Visit, or as needed. Per local regulation LTE and Safety Follow-up Visit 
Pregnancy tests may be perfonned in-clinic. 
The site will call the subject every 4 weeks during the LTE or at the Safety Follow-up Visit, if 
there is not a clinic visit scheduled, in order to obtain results. Results will be recorded in the 
source documents and eCRF. If any pregnancy test is positive, study drug should be iimnediately 
interrupted and the subject should present to the site for further evaluation and testing, including 
a serum pregnancy test. 
6.6.5. 
Laboratory Assessments 
. A list of scheduled laboratory tests for this study is available in Appendix 5. 
Reference ranges will be supplied by the central laboratory and will be used by the investigator 
to assess the laboratory data for clinical significance and pathological changes. 
Blood samples will be collected by venipuncture 
at 
the tune points indicated in the Study Procedures Table (Appendix 2). In addition, uriI1e samples 
for the clinical laboratory assessments will be collected. FastiI1g (no food or drinks, except water) 
of at least 8 hours will be required prior to collection of blood samples for lipid testing only. 
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Laboratory values outside the nonnal range will be flagged and clinical relevance will be 
assessed by the investigator. Following up on laboratory abnonnalities is the responsibility of the 
investigator. More frequent sampling as well as additional tests may be perfonned as deemed 
necessary by the investigator. 
NOTE: In the case where clinically significant laboratory test results are a potential reason for 
discontinuation from the study drug, retesting of the affected parameter(s) should be prompt 
(~7 days) after the investigator has consulted with the Gilead Medical Monitor or designee. A 
decision regarding subject discontinuation from study drug should be made after the results from 
the retest are available. 
The details of sample handling and shipment instructions will be provided in a separate 
laboratory manual. 
6.6.5.1. 
Tuberculosis Testing 
Testing will be perfonned as a combination of a QuantiFERON®TB-Gold Plus (QFT) central 
laboratory test AND a chest X-ray at the time points indicated in the Study Procedures 
Table (Appendix 2). Assessment of active or latent TB may be detennined when both the QFT 
and X-ray results are available. Local laboratory tests are not allowed. 
Screening TB Testing 
Tuberculosis testing will be perfonned at the Screening Visit as outlined below: 
Figure 6-1. 
Tuberculosis Testing at the Screening Visit 
~1 ----~1---1.. 
f------~1 
~r 
-~ 
bieligible 
Documentation of a 
completed e-0urse of TS 
therapy per local guidelines 
WITH a negative chest 
X-ray $3 months of 
screening 
\'cs 
Ne·• 
~---'l'---, ~l.L.----~ 
No QFT needed, 
subject is eligible 
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lndetenni,rnlt 
Qn 
Repeal QfT 
(If indctcnninatc again, 
treat as positive) 
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QfT & chest X-ray 
required 
Negt\lht 
QFT 
Fwthcr assessment via 
chest X-ray 
Pc,~itin• 
QFT 
Ineligible 
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If subjects have active TB, defined as a positive QFT and / or positive chest X-ray, they will not 
be pennitted to enroll in the study, per Section 4.2. 
Subjects with a history of latent TB, defined as a positive QFT and negative chest X-ray, must 
have documentation of a completed course of therapy, as per local standard of care, WITH a 
negative chest X-ray :S3 months of the Screening Visit. In these cases, no QFT should be 
perfonned. Subjects who have a history of latent TB with no documentation of a completed 
course of therapy will be ineligible to enroll, per Section 4.2. Subjects with latent TB can be 
screened for this study if they complete a course of latent TB therapy. 
Subjects with positive QFT results from the central laboratory may not repeat QFTs in a local or 
the central laboratory; subjects must screen fail and should be treated per local standard. 
Subjects with indetenninate QFT results may repeat the QFT only once through the central 
laboratory. If the repeat result is also indetenninate, the result will be considered positive for the 
purposes of this study and subjects should be evaluated for active TB via a chest X-ray. If the 
chest X-ray is negative the subject will be allowed to enter the study only after completion of 
latent TB therapy per local guidelines and provide appropriate documentation. If the chest X-ray 
is positive the subject will not be allowed to enter the study and should seek medical attention 
per local guidelines. QFT tests with indetenninate results can be repeated only once. 
LTE TB Testing 
Tuberculosis testing will be perfonned during the LTE as outlined below: 
Figure 6-2. 
Tuberculosis Testing During the LTE 
~-----1 History oflatentTB! 1-------~I 
No 
Annual 
Annual 
chest X-ray required 
QFT & chest X-ray 
required 
Posifin~ 
Discontinue study 
Continue on study 
Indeterminate 
on 
Repeat QFT 
Negative 
on 
Negatil,•e 
Further assessment via 
on 
chest X-ray 
lodeltnnina.tt. or Posith-t. 
Posith'e 
Neg:11ive 
OFT 
Positi,·e 
on 
.. 
Discontinue study 
Discontinue study 
Continue on study 
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Subjects with a history of latent TB will be monitored annually with a chest X-ray. No QFT 
should be perfonned as indicated in Appendix 2. 
Subjects without a history of TB will be monitored with an ammal QFT and chest X-ray 
• 
For subjects with negative QFT results, a chest X-ray is required 
• 
For subjects with newly positive (converted) QFT results, subjects must immediately 
discontinue study drug, discontinue study and be evaluated for active TB. A positive initial 
test cannot be followed by a repeat test. 
• 
For subjects with indetenninate QFT results, subjects must immediately interrupt study 
drug, and repeat the QFT via central laboratory with an Unscheduled Visit (in <2 weeks from 
the visit) and be evaluated for active TB. If the repeat result is also indetenn inate, the result 
will be considered positive for the purposes of this study and subjects should discontinue 
study and be evaluated for active TB. QFT tests with indetenninate results can be repeated 
only once. 
6.6.5.2. 
Viral Monitoring 
Subjects who test positive for chronic HBV or HCV at Screening will be monitored as outlined 
in the Study Procedures Table (Appendix 2). 
6.6.6. 
6.6.6.1. 
Imaging Assessments 
MRI 
MRis will be perfonned at site when and where available. MRis will be taken on one 
hand / wrist prior to the first dose of study drug and repeated at the Week 16 Visit. Assessment 
will be on the same hand / wrist throughout the study. MRis will be scored by central read as 
outlined in the imaging manual. 
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7.
ADVERSE EVENTS AND TOXICITY MANAGEMENT
7.1.
Definitions of Adverse Events, Adverse Reactions, and Serious Adverse 
Events
7.1.1.
Adverse Events
An adverse event (AE) is any untoward medical occurrence in a clinical study subject 
administered a medicinal product, which does not necessarily have a causal relationship with the
treatment. An AE can therefore be any unfavorable and / or unintended sign, symptom, or 
disease temporally associated with the use of a medicinal product, whether or not considered 
related to the medicinal product. AEs may also include pre- or post-treatment complications that 
occur as a result of protocol specified procedures, lack of efficacy, overdose, drug abuse / misuse 
reports, or occupational exposure. Pre-existing events that increase in severity or change in 
nature during or as a consequence of participation in the clinical study will also be considered 
AEs.
An AE does not include the following:

Medical or surgical procedures such as surgery, endoscopy, tooth extraction, and transfusion.
The condition that led to the procedure may be an adverse event and must be reported

Pre-existing diseases, conditions, or laboratory abnormalities present or detected before the 
Screening Visit that do not worsen

Situations where an untoward medical occurrence has not occurred (e.g. hospitalization for 
elective surgery, social and / or convenience admissions)

Overdose without clinical sequelae (see Section 7.7.1)

Any medical condition or clinically significant laboratory abnormality with an onset date 
before the consent form is signed and not related to a protocol-associated procedure is not an 
AE. It is considered to be pre-existing and should be documented on the medical history 
eCRF.
7.1.2.
Serious Adverse Events
A serious adverse event (SAE) is defined as an event that, at any dose, results in the following:

Death

Life-threatening (NOTE: The term “life-threatening” in the definition of “serious” refers to 
an event in which the subject was at risk of death at the time of the event; it does not refer to 
an event that hypothetically might have caused death if it were more severe.)


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
In-patient hospitalization or prolongation of existing hospitalization

Persistent or significant disability / incapacity

A congenital anomaly / birth defect

A medically important event or reaction: such events may not be immediately 
life-threatening or result in death or hospitalization but may jeopardize the subject or may 
require intervention to prevent one of the other outcomes constituting SAEs. Medical and 
scientific judgment must be exercised to determine whether such an event is a reportable 
under expedited reporting rules. Examples of medically important events include intensive 
treatment in an emergency room or at home for allergic bronchospasm; blood dyscrasias or 
convulsions that do not result in hospitalization; and development of drug dependency or 
drug abuse. For the avoidance of doubt, infections resulting from contaminated medicinal 
product will be considered a medically important event and subject to expedited reporting 
requirements.
7.1.3.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events
Laboratory abnormalities without clinical significance are not recorded as AEs or SAEs. 
However, laboratory abnormalities (e.g. clinical chemistry, hematology, and urinalysis) that 
require medical or surgical intervention or lead to study drug interruption, modification, or 
discontinuation must be recorded as an AE, as well as an SAE, if applicable. In addition, 
laboratory or other abnormal assessments (e.g. electrocardiogram, X-rays, vital signs) that are 
associated with signs and / or symptoms must be recorded as an AE or SAE if they meet the 
definition of an AE or SAE as described in Sections 7.1.1 and 7.1.2. If the laboratory 
abnormality is part of a syndrome, record the syndrome or diagnosis (e.g. anemia), not the 
laboratory result (i.e. decreased hemoglobin).
For specific information on handling of clinical laboratory abnormalities in this study, please 
refer to Section 7.5.
7.2.
Assessment of Adverse Events and Serious Adverse Events
The investigator or qualified subinvestigator is responsible for assessing AEs and SAEs for 
causality and severity, and for final review and confirmation of accuracy of event information 
and assessments.
7.2.1.
Assessment of Causality for Study Drugs and Procedures
The investigator or qualified subinvestigator is responsible for assessing the relationship to study 
drug therapy using clinical judgment and the following considerations:

No: Evidence exists that the AE has an etiology other than the study drug. For SAEs, an 
alternative causality must be provided (e.g. pre-existing condition, underlying disease, 
intercurrent illness, or concomitant medication).

Yes: There is reasonable possibility that the event may have been caused by the 
investigational medicinal product.


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It should be emphasized that ineffective treatment should not be considered as causally related in 
the context of AE reporting.
The relationship to study procedures (e.g. invasive procedures such as venipuncture or biopsy) 
should be assessed using the following considerations:

No: Evidence exists that the adverse event has an etiology other than the study procedure.

Yes: The adverse event occurred as a result of protocol procedures, (e.g. venipuncture).
7.2.2.
Assessment of Severity
The severity of AEs will be graded using the modified Common Terminology Criteria for 
Adverse Events (CTCAE), version 5.0. For each episode, the highest grade attained should be 
reported.
If a CTCAE criterion does not exist, the investigator should use the grade or adjectives: 
Grade 1 (mild), Grade 2 (moderate), Grade 3 (severe), Grade 4 (life-threatening) or 
Grade 5 (fatal/death) to describe the maximum intensity of the adverse event. For purposes of 
consistency with the CTCAE, these intensity grades are defined in Table 7-1 below.
Table 7-1.
Grading of Adverse Event Severity
Grade
Adjective
Description
Grade 1
Mild
Asymptomatic or mild symptoms; clinical or diagnostic observations 
only; intervention not indicated 
Grade 2
Moderate
Local or noninvasive intervention indicated; limiting age-appropriate 
instrumental ADL*
Grade 3
Severe
Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling; 
limiting self-care ADL**
Grade 4
Life-threatening
Urgent intervention indicated 
Grade 5
Fatal/Death 
Fatal/Death related AE 
*
Activities of Daily Living (ADL) Instrumental ADL refer to opening preparing meals, shopping for groceries or clothes, 
using the telephone, managing money, etc. 
**
Self-care ADL refer to bathing, dressing and undressing, feeding self, using the toilet, taking medications, and not 
bedridden.
https://ctep.cancer.gov/protocolDevelopment/electronic_applications/docs/CTCAE_v5_Quick_R
eference_8.5x11.pdf
The only modification to the CTCAE criteria is the addition of a Grade 1 upper respiratory 
infection outlined in Table 7-2 below.


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NOTE: Upper respiratory infection is defined as a disorder characterized by an infectious 
process involving the upper respiratory tract (nose, paranasal sinuses, pharynx, larynx, or 
trachea).
Table 7-2
Grading of Upper Respiratory Infection Severity
Grade
Adjective
Description
Grade 1
Mild
Mild symptoms; symptomatic relief (e.g. cough suppressant, 
decongestant)
Grade 2
Moderate
Moderate symptoms; oral intervention indicated (e.g. antibiotic, 
antifungal, antiviral)
Grade 3
Severe
IV antibiotic, antifungal, or antiviral intervention indicated; radiologic, 
endoscopic, or operative intervention indicated
Grade 4
Life-threatening
Life-threatening consequences; urgent intervention indicated
Grade 5
Fatal/Death
Fatal/Death
7.3.
Investigator Requirements and Instructions for Reporting Adverse Events 
and Serious Adverse Events to Gilead
Requirements for collection prior to study drug initiation:
After informed consent, but prior to initiation of study medication, the following types of events 
should be reported on the eCRF: all SAEs and AEs related to protocol-mandated procedures.
Adverse Events
Following initiation of study medication, collect all AEs, regardless of cause or relationship, 
throughout the duration of the study, including at the protocol-required Safety Follow-up Visit
must be reported to the eCRF database as instructed.
All AEs should be followed up until resolution or until the AE is stable, if possible. 
Gilead Sciences may request that certain AEs be followed beyond the protocol defined follow-up 
period.
Serious Adverse Events
All SAEs, regardless of cause or relationship, that occurs after the subject first consents to 
participate in the study (i.e. signing the informed consent) and throughout the duration of the 
study, including 30 days after last in clinic visit, must be reported to the eCRF database and 
Gilead PVE, as instructed. This also includes any SAEs resulting from protocol-associated 
procedures performed after informed consent is signed.


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Investigators are not obligated to actively seek SAEs after the protocol defined follow-up period; 
However, if the investigator learns of any SAEs that occur after study participation has 
concluded and the event is deemed relevant to the use of study drug, he / she should promptly 
document and report the event to Gilead PYE. 
• 
All AEs and SAEs will be recorded in the eCRF database within the timelines outlined in the 
eCRF completion guideline. 
Electronic Serious Adverse Event (eSAE) Reporting Process 
• 
Site perso1mel record all SAE data in the eCRF database and from there transmit the SAE 
infonnation to Gilead PYE :S24 hours of the investigator's knowledge of the event. Detailed 
instructions can be found in the eCRF completion guidelines. 
• If for any reason it is not possible to record the SAE infonnation electronically, i.e. the eCRF 
database is not functioning, record the SAE on the paper serious adverse event reporting 
fonn and submit :S24 hours to: 
Gilead PYE: Fax: 
IPD 
E-mail: IPIPD 
• 
As soon as it is possible to do so, any SAE reported via paper must be transcribed into the 
eCRF Database according to instructions in the eCRF completion guidelines. 
• If an SAE has been reported via a paper fonn because the eCRF database has been locked, no 
further action is necessary. 
• 
All AEs and SAEs will be recorded in the eCRF database within the timelines outlined in the 
eCRF completion guideline. 
• 
For fatal or life-threatening events, copies of hospital case reports, autopsy reports, and other 
documents are also to be submitted by e-mail or fax when requested and applicable. 
Transmission of such documents should occur without personal subject identification, 
maintaining the traceability of a document to the subject identifiers. 
• 
Additional infonnation may be requested to ensure the timely completion of accurate safety 
reports. 
• 
Any medications necessary for treatment of the SAE must be recorded onto the concomitant 
medication section of the subject's eCRF and the event description section of the SAE fonn. 
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7.4.
Gilead Reporting Requirements
Depending on relevant local legislation or regulations, including the applicable US FDA Code of 
Federal Regulations, the EU Clinical Trials Directive (2001 / 20 / EC) and relevant updates, and 
other country-specific legislation or regulations, Gilead may be required to expedite to 
worldwide regulatory agencies reports of SAEs, serious adverse drug reactions (SADRs), or 
SUSARs. In accordance with the EU Clinical Trials Directive (2001 / 20 / EC), Gilead or a 
specified designee will notify worldwide regulatory agencies and the relevant IEC in concerned 
Member States of applicable SUSARs as outlined in current regulations.
Assessment of expectedness for SAEs will be determined by Gilead using reference safety 
information specified in the investigator’s brochure. Assessment of expectedness for 
adalimumab SAEs will be determined by the adalimumab EU SmPC (SmPC Section 4.8) or 
relevant local label as applicable.
All investigators will receive a safety letter notifying them of relevant SUSAR reports associated 
with any study drug. The investigator should notify the IRB / IEC of SUSAR reports as soon as 
is practical, where this is required by local regulatory agencies, and in accordance with the local 
institutional policy.
7.5.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events
Laboratory abnormalities are usually not recorded as AEs or SAEs. However, laboratory 
abnormalities (e.g. clinical chemistry, hematology, and urinalysis) independent of the 
underlying medical condition that require medical or surgical intervention or lead to 
investigational medicinal product interruption or discontinuation must be recorded as an AE or 
SAE, as applicable. In addition, laboratory or other abnormal assessments (e.g. ECG, X-rays, 
vital signs) that are associated with signs and / or symptoms must be recorded as an AE or SAE 
if they meet the definition of an AE (or SAE) as described in Sections 7.1.1 and 7.1.2. If the 
laboratory abnormality is part of a syndrome, record the syndrome or diagnosis (i.e. anemia) not 
the laboratory result (i.e. decreased hemoglobin).
Adverse events will be coded using the most recent version of the Medical Dictionary for 
Regulatory Activities (MedDRA). Severity should be recorded and graded according to the 
CTCAE Version 5.0, which can be found at:
https://ctep.cancer.gov/protocolDevelopment/electronic_applications/docs/CTCAE_v5_Quick_R
eference_8.5x11.pdf
For AEs associated with laboratory abnormalities, the event should be graded on the basis of the 
clinical severity in the context of the underlying conditions; this may or may not be in agreement 
with the grading of the laboratory abnormality.
All clinical and clinically significant laboratory toxicities will be managed according to uniform 
guidelines detailed in Appendix 4 and as outlined below.


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7.5.1.
Grades 1 and 2 Laboratory Abnormality or Clinical Event

For study specific interruption and stopping criteria, please refer to Section 3.5 (Criteria for 
Interruption or Discontinuation of study treatment)
7.5.2.
Grades 3 Laboratory Abnormality or Clinical Event

For study specific interruption and stopping criteria, please refer to Section 3.5 (Criteria for 
Interruption or Discontinuation of study treatment)

For Grades 3 Laboratory Abnormality or Clinical Event not specified in Section 3.5, the 
following toxicity management guidelines apply:
For Grade 3 clinically significant laboratory abnormality or clinical event, study drug
may be continued if the event is considered to be unrelated to study drug.
For a Grade 3 clinical event, or clinically significant laboratory abnormality confirmed by 
repeat testing, that is considered to be related to study drug, investigational medicinal 
product should be withheld until the toxicity returns to ≤Grade 2.
If a laboratory abnormality recurs to ≥Grade 3 following re-challenge with study drug
and is considered related to study drug, then study drug should be permanently 
discontinued and the subject managed according to local clinical practice. Recurrence of 
laboratory abnormalities considered unrelated to study drug may not require permanent 
discontinuation.
7.5.3.
Grades 4 Laboratory Abnormality or Clinical Event

For study specific interruption and stopping criteria, please refer to Section 3.5 (Criteria for 
Interruption or Discontinuation of study treatment)

For Grade 4 Laboratory Abnormality or Clinical Event not specified in Section 3.5, the 
following toxicity management guidelines apply:
For a Grade 4 clinical event or clinically significant Grade 4 laboratory abnormality 
confirmed by repeat testing that is considered related to study drug, study drug should be 
permanently discontinued and the subject managed according to local clinical practice. 
The subject should be followed as clinically indicated until the laboratory abnormality 
returns to baseline or is otherwise explained, whichever occurs first. A clinically 
significant Grade 4 laboratory abnormality that is not confirmed by repeat testing should 
be managed according to the algorithm for the new toxicity grade.

Study drug may be continued without dose interruption for a clinically non-significant 
Grade 4 laboratory abnormality (e.g. Grade 4 creatine kinase (CK) after strenuous exercise or 
triglyceride elevation that is non-fasting or that can be medically managed) or a clinical event 
considered unrelated to investigational medicinal product.


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7.6.
Toxicity Management 
Treatment-emergent toxicities will be noted by the investigator and brought to the attention of
the Gilead Sciences Medical Monitor or designee, who will have a discussion with the 
investigator and decide the appropriate course of action. Whether or not considered 
treatment-related, all subjects experiencing AEs must be monitored periodically until symptoms 
subside, any abnormal laboratory values have resolved or returned to baseline levels or they are 
considered irreversible, or until there is a satisfactory explanation for the changes observed.
Any questions regarding toxicity management should be directed to the Gilead Sciences Medical 
Monitor or designee.
7.6.1.
Thromboembolic Events
Subjects experiencing a thromboembolic event should be evaluated for the overall risk of 
recurrent thromboembolism and referred to a specialist for further testing as appropriate 
(including but not limited to evaluation for an underlying inherited hypercoagulable state).
7.7.
Special Situations Reports
7.7.1.
Definitions of Special Situations
Special situation reports include all reports of medication error, abuse, misuse, overdose, 
occupational exposure, drug interactions, exposure via breastfeeding, unexpected benefit, 
transmission of infectious agents via the product, counterfeit or falsified medicine, and 
pregnancy regardless of an associated AE. 
Medication error is any unintentional error in the prescribing, dispensing, preparation for 
administration or administration of an investigational product while the medication is in the 
control of a health care professional, patient, or consumer. Medication errors may be classified as 
a medication error without an AE, which includes situations of missed dose; medication error 
with an AE; intercepted medication error; or potential medication error.
Abuse is defined as persistent or sporadic intentional excessive use of an investigational product 
by a subject.
Misuse is defined as any intentional and inappropriate use of an investigational product that is 
not in accordance with the protocol instructions or the local prescribing information.
An overdose is defined as an accidental or intentional administration of a quantity of an 
investigational product given per administration or cumulatively which is above the maximum 
recommended dose as per protocol or in the product labeling (as it applies to the daily dose of the 
subject in question). In cases of a discrepancy in drug accountability, overdose will be 
established only when it is clear that the subject has taken the excess dose(s). Overdose cannot 
be established when the subject cannot account for the discrepancy except in cases in which the 
investigator has reason to suspect that the subject has taken the additional dose(s).


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Occupational exposure is defined as exposure to an investigational product as a result of one’s 
professional or non-professional occupation.
Drug interaction is defined as any drug/drug, drug/food, or drug/device interaction.
Unexpected benefit is defined as an unintended therapeutic effect where the results are judged to 
be desirable and beneficial. 
Transmission of infectious agents is defined as any suspected transmission of an infected agent 
through a GSI investigational product.
Counterfeit or falsified medicine is defined as any investigational product with a false 
representation of: a) its identity, b) its source, or c) its history.
7.7.2.
Instructions for Reporting Special Situations
7.7.2.1.
Instructions for Reporting Pregnancies
The investigator should report pregnancies in female study subjects that are identified after 
initiation of study medication and throughout the study, including the post study drug follow-up 
period, to Gilead PVE using the pregnancy report form within 24 hours of becoming aware of 
the pregnancy.
Refer to Section 7.3 and the eCRF completion guidelines for full instructions on the mechanism 
of pregnancy reporting.
The pregnancy itself is not considered an AE nor is an induced elective abortion to terminate a 
pregnancy without medical reasons.
Any premature termination of pregnancy (e.g. a spontaneous abortion, an induced therapeutic 
abortion due to complications or other medical reasons) must be reported within 24 hours as an 
SAE. The underlying medical reason for this procedure should be recorded as the AE term.
A spontaneous abortion is always considered to be an SAE and will be reported as described in 
Sections 7.1.1 and 7.1.2. Furthermore, any SAE occurring as an adverse pregnancy outcome post 
study must be reported to Gilead PVE.
The subject should receive appropriate monitoring and care until the conclusion of the 
pregnancy. The outcome should be reported to Gilead PVE using the pregnancy outcome report 
form. If the end of the pregnancy occurs after the study has been completed, the outcome should 
be reported directly to Gilead PVE. Gilead PVE contact information is as follows: 
Email:
 and Fax: 
.
PPD
PPD


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Pregnancies of female partners of male study subjects exposed to Gilead or other study drugs 
must also be reported and relevant information should be submitted to Gilead PVE using the 
pregnancy and pregnancy outcome forms within 24 hours. Monitoring of the subject should 
continue until the conclusion of the pregnancy. If the end of the pregnancy occurs after the study 
has been completed, the outcome should be reported directly to Gilead PVE, 
fax number
 or email
Refer to Appendix 3 or Pregnancy Precautions, Definition for Female of Childbearing Potential, 
and Contraceptive Requirements.
7.7.2.2.
Reporting Other Special Situations
All other special situation reports must be reported on the special situations report form and 
forwarded to Gilead PVE within 24 hours of the investigator becoming aware of the situation. 
These reports must consist of situations that involve study drug (including adalimumab) and / or 
other Gilead medications.
Special situations involving non-Gilead medications do not need to be reported on the special 
situations report form; however, for special situations that result in AEs due to a non-Gilead 
medication(s), the AE should be reported on the AE form. 
Any inappropriate use of concomitant medications prohibited by this protocol should not be 
reported as “misuse,” but may be more appropriately documented as a protocol deviation.
Refer to Section 7.3 and the eCRF completion guidelines for full instructions on the mechanism 
of special situations reporting.
All clinical sequelae in relation to these special situation reports will be reported as AEs or SAEs 
at the same time using the AE eCRF and / or the SAE report form. Details of the symptoms and 
signs, clinical management, and outcome will be reported, when available.
PPD
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8. 
STATISTICAL CONSIDERATIONS 
8.1. 
Analysis Objectives and Endpoints 
8.1.1. 
Analysis Objectives 
Analysis objectives are aligned with the objectives specified in Section 2. 
8.1.2. 
Primary Endpoint 
The primary endpoint is listed in Section 3.1.1. 
The primary null hypotheses are listed in Appendix 6. 
8.1.3. 
Secondary Endpoints 
The key secondary endpoints, other secondary 
Sections 3.1.2 and 3.1.3. 
The key secondary hypotheses are listed in Appendix 6. 
8.2. 
8.2.1. 
8.2.1.1. 
Analysis Conventions 
Analysis Sets 
Efficacy 
endpoints are listed in 
Final 
Amendment2 
The primary analysis set for efficacy analyses will be the Full Analysis Set (FAS), which 
includes all randomized subjects who received at least one dose of study drug. 
8.2.1.2. 
Safety 
The primary analysis set for safety analyses will be the Safety Analysis Set, which includes all 
subjects who received at least one dose of study drug. 
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8.3.
Data Handling Conventions
Values for missing safety laboratory data will not be imputed. If no baseline laboratory value is 
available, the baseline value will be assumed to be normal (i.e. no grade [Grade 0]) for the 
summary of graded laboratory abnormalities. If the safety laboratory results for a subject are 
missing for any reason at a time point, the subject will be excluded from the calculation of 
summary statistics for that time point.
Laboratory data that are continuous in nature but are less than the lower limit of quantitation or 
above the upper limit of quantitation will be imputed to the value of the lower or upper limit 
minus or plus one significant digit, respectively (e.g. if the result of a continuous laboratory test 
is <20, a value of 19 will be assigned; if the result of a continuous laboratory test is <20.0, a 
value of 19.9 will be assigned).
8.4.
Demographic Data and Baseline Characteristics
Demographic and baseline measurements will be summarized using standard descriptive 
methods – 8-number summary (n, mean, SD, median, Q1, Q3, minimum, maximum) for 
continuous variables and the number and percentage of subjects per category for categorical 
variables.
Demographic summaries will include sex, race, ethnicity, and age.
Baseline characteristics will include randomization stratification factors, serum CRP, joint 
counts, HAQ-DI, and other variables of interest.
8.5.
Efficacy Analysis
All continuous efficacy endpoints will be summarized using 8-number summary (n, mean, SD, 
median, Q1, Q3, minimum, maximum) by treatment group. All categorical efficacy endpoints 
will be summarized with the number and percentage of subjects who meet the endpoint or 
category definition by treatment group.
Besides the efficacy analyses specified in the protocol, sensitivity analyses may be performed for 
the efficacy assessments. More details on efficacy analyses will be described in the SAP.
8.5.1.
Primary Analysis
8.5.1.1.
Primary Estimand
The primary estimand corresponding to the treatment policy strategy is defined by the 
4 attributes below:
1) Population: subjects in the FAS.
2) Variable / endpoint: binary ACR20 response variable at Week 12 indicating if a subject 
meets the ACR20 response criteria at Week 12.


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3) Accounting for intercurrent events: include all on-study data regardless of protocol 
violations, use of rescue medication, change in background medication, and study drug
discontinuation.
4) Population-level summary: the treatment difference in the percentage of subjects meeting
ACR20 response criteria between each filgotinib group and the placebo group.
8.5.1.2.
Main Estimator
A logistic regression analysis with treatment groups and stratification factors in the model will be 
used to analyze the primary endpoint. For subjects who do not have sufficient measurements to 
establish efficacy at Week 12, their data will be imputed using multiple imputation assuming that 
missing data are missing at random (MAR).
Sensitivity analyses to evaluate the robustness of results to violations of any assumptions made 
regarding the data missingness mechanisms will be specified in the SAP.
8.5.2.
Secondary Analyses
8.5.2.1.
Estimand
The main estimand corresponding to the treatment policy strategy for the key secondary 
endpoints is defined with the same attributes as in the primary estimand except that the 
variable / endpoint and population-level summary are endpoint specific. The key secondary 
endpoints are listed in Section 3.1.2. For the binary endpoints, the population-level summary is 
the treatment difference in the percentage of subjects meeting specified criteria for response
between each filgotinib group and the placebo group. For the continuous endpoints, the 
population-level summary is the mean treatment difference between each filgotinib group and 
the placebo group.
8.5.2.2.
Estimator
8.5.2.2.1.
Superiority Test
For a superiority test of each filgotinib group compared to the placebo group on a binary efficacy 
endpoint, a logistic regression analysis with treatment groups and stratification factors in the 
model will be used.
For a superiority test of each filgotinib group compared to the placebo group on a continuous 
efficacy endpoint that is longitudinally collected, a mixed-effect model repeated measures 
(MMRM) analysis with treatment groups and stratification factors as fixed effects and subjects 
as a random effect in the model will be used. The model may also include visit, 
treatment-by-visit interaction, and the continuous baseline value as fixed effects.


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8.5.2.2.2.
Non-inferiority Test
The non-inferiority hypothesis based on the response rate of ACR20 at Week 12 (Appendix 6) 
will be tested using the 3-arm design approach proposed by {Liu 2014}, which utilize the data 
collected from the placebo, filgotinib, and adalimumab groups. The traditional non-inferiority 
null hypothesis is :  −
 ≤− where:  is the response rate for the treatment group 
(i.e. filgotinib), 
is the response rate for the active control group (i.e. adalimumab), and  is the 
non-inferiority margin, where  = (1 – )(
 – ) is usually estimated from historical data and 
is the response rate for the placebo group. For the 3-arm design, the null hypothesis can be 
equivalently transformed to :

 ≤. For this hypothesis testing, the response rates for the 
active control and placebo groups are estimated from the study data. A value of 0.5 is selected 
for , implying that the treatment is “at least as good as or non-inferior to” the active control 
{Koch 1999}.
8.5.3.
Hypothesis Testing Strategy
The graphical approach to sequentially rejective multiple test procedures (Appendix 6 and 
Appendix 7) will be used to control a family wise type I error rate at 5% (i.e. α = 0.05). 
Within each filgotinib dosing regimen, the primary hypothesis will be first tested at α/2. If the 
primary hypothesis is rejected, then the next secondary hypothesis in the same filgotinib dosing 
regimen will be tested at α/2. Testing of the hypotheses happens sequentially in the same 
filgotinib dosing regimen. Once all hypotheses within the same filgotinib dosing regimen are 
rejected, then the respective α/2 can be passed on to the other regimen’s hypotheses, that is, all 
hypotheses in the other filgotinib dosing regimen will be tested at α level. 
The order of the key secondary hypotheses will be specified in the SAP.
8.6.
Safety Analysis
All safety analyses will be performed using the Safety Analysis Set. Safety will be evaluated by 
assessments of clinical laboratory tests, physical examinations, vital signs measurements at 
various time points during the study, and by the documentation of AEs. 
Safety endpoints will be summarized with the number and percentage of subjects with events or 
abnormalities for categorical values or 8-number summary (n, mean, SD, median, Q1, Q3, 
minimum, maximum) for continuous data by treatment group. 
Two safety estimands, treatment policy and while on treatment, will be applied for the safety 
analysis. 
In the analysis for the treatment policy estimand, all the safety data collected in the study will be
included in the analysis. For while on treatment estimand, all the safety data collected up to 
30 days after the last dose date of study drug will be included in the analysis. More details on 
safety analyses will be described in the SAP.


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8.6.1.
Extent of Exposure
A subject’s extent of exposure to study drug will be generated from the study drug 
administration page of the eCRF. Exposure data will be summarized by treatment group. The 
duration of exposure to study drug will be expressed as the number of weeks between the 
first and last dose dates of study drug, inclusive, regardless of temporary interruptions in study 
drug administration and summarized by treatment group.
8.6.2.
Adverse Events
Clinical and laboratory AEs will be coded using the MedDRA. System Organ Class, High-Level 
Group Term (HLGT), High-Level Term (HLT), Preferred Term (PT), and Lower-Level Term 
(LLT) will be attached to the clinical database.
Treatment-Emergent Adverse Events (TEAEs) are:

Any AEs with an onset date of on or after the study drug start date and no later than the 
“analysis end date,” which is defined separately for treatment policy estimand and while on 
treatment estimand as follows: 
Treatment policy estimand: the latest date of either the last reported date in the study or 
30 days after permanent discontinuation of study drug
While on treatment estimand: 30 days after permanent discontinuation of study drug
OR

Any AEs leading to premature discontinuation of study drug.
Summaries (number and percentage of subjects) of TEAEs by System Organ Class and PT will 
be provided by treatment group. TEAEs will also be summarized by relationship to study drug 
and severity. In addition, TEAEs leading to premature discontinuation of study drug will be 
summarized and listed.
8.6.3.
Laboratory Evaluations
Selected laboratory data will be summarized using only observed data. Data and change from 
Baseline at all scheduled time points will be summarized. 
Graded laboratory abnormalities will be defined using the CTCAE version 5.0 grading scheme. 
The incidence of treatment-emergent graded laboratory abnormalities will be summarized by 
treatment group.


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Protocol GS-US-431-4566 
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8.9. 
Sample Size 
Final 
Amendment2 
Sample size is detennined based on the non-inferiority test of each filgotinib group compared to 
the adalimumab group on the ACR20 response rate at Week 12. When assuming the ACR20 
response rate being 52% and 60% for the adalimumab and each filgotinib group, and 38.6% for 
the placebo group, 244 subjects in each filgotinib group and placebo group, and 122 subjects in 
the adalimumab group are required to obtain 90% power at a two-sided 0.025 significance level 
to demonstrate that filgotinib group preserves more than 50% of the effect of adalimmnab with 
respect to the ACR20 response rate at Week 12. 
A sample size of 244 subjects in each filgotinib group and the placebo group will provide over 
95% power to detect a difference in ACR20 response rate of 21.4% at Week 12 (38.6% and 
60% for the placebo group and each filgotinib group, respectively) using a two-sided 
0.025 significance level superiority test. 
In smmnary, the total sample size will be approximately 854 subjects. 
8.10. 
Data Monitoring Committee 
An external multidisciplinary DMC will review the progress of the study and perfonn interim 
reviews of safety data and provide reco1mnendation to Gilead whether the nature, frequency, and 
severity of AEs associated with study treatment warrant the early tennination of the study in the 
best interests of the participants, whether the study should continue as planned, or the study 
should continue with modifications. The DMC may also provide reco1mnendations as needed 
regarding study design. 
CONFIDENTIAL 
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If there is a recommendation from the DMC to stop the study early or other significant action 
due to a potential safety issue, the appropriate GSI Representative may be provided with the 
unblinded DMC closed session reports, as needed, to escalate to the appropriate safety
committee (per GSI’s signal management process) to make an informed decision. Unblinding of 
specific GSI personnel will be documented per the appropriate SOPs.
The DMC’s specific activities will be defined by a mutually agreed charter, which will define the 
DMC’s membership, conduct and meeting schedule.
While the DMC will be asked to advise Gilead regarding future conduct of the study, including 
possible early study termination, Gilead retains final decision-making authority on all aspects of 
the study.
8.11.
Event Adjudication Committee for Major Adverse Cardiovascular Events 
and Thromboembolic Events
An independent adjudication committee governed by a charter will be set up to perform 
adjudication of potential major adverse cardiovascular events as well as thromboembolic events 
reported during the study. The adjudication of these events will be performed in a blinded 
fashion for the purposes of data analysis, and not for monitoring of subject safety. 
Additional information regarding the logistics of adjudication will be described in the charter.
8.12.
Week 16 Analysis
A Week 16 analysis is planned after all randomized subjects have completed their Week 16 Visit 
(or prematurely discontinued from the study prior to Week 16). The time point of the primary 
efficacy endpoint is Week 12. The time points of the key secondary efficacy endpoints are 
Week 12 and Week 16. Therefore, at the time of the Week 16 analysis, all the primary and key 
secondary endpoints / hypotheses can be evaluated.
8.13.
Interim Analysis in LTE
Interim analyses in the LTE may be performed at the Sponsor’s discretion. 
A Week 48 Interim Analysis in LTE will be performed if deemed necessary per the Sponsor’s 
discretion when all enrolled subjects have completed their Week 48 Visit (or prematurely 
discontinued from the study prior to Week 48). 
No adjustment for multiplicity will be applied for interim analyses in LTE because all analyses 
will be mainly descriptive.


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9.
RESPONSIBILITIES
9.1.
Investigator Responsibilities
9.1.1.
Good Clinical Practice
The investigator will ensure that this study is conducted in accordance with ICH E6(R2) Good 
Clinical Practices and applicable laws and regulations.
9.1.2.
Financial Disclosure
The investigator and subinvestigators will provide documentation of their financial interest or 
arrangements with Gilead, or proprietary interests in the investigational drug under study. This 
documentation must be provided prior to the investigator’s (and any subinvestigator’s) 
participation in the study. The investigator and subinvestigator agree to notify Gilead of any 
change in reportable interests during the study and for 1 year following completion of the study. 
Study completion is defined as the date when the last subject completes the protocol-defined 
activities.
9.1.3.
Institutional Review Board (IRB) / Independent Ethics Committee (IEC) 
Review and Approval
The investigator (or Sponsor as appropriate according to local regulations) will submit this 
protocol, informed consent form, and any accompanying material to be provided to the subject 
(such as advertisements, subject information sheets, or descriptions of the study used to obtain 
informed consent) to an IRB / IEC. The investigator will not begin any study subject activities 
until approval from the IRB / IEC has been documented and provided as a letter to the 
investigator.
Before implementation, the investigator will submit to and receive documented approval from 
the IRB / IEC any modifications made to the protocol or any accompanying material to be 
provided to the subject after initial IRB / IEC approval, with the exception of those necessary to 
reduce immediate risk to study subjects.
9.1.4.
Informed Consent
The investigator is responsible for obtaining written informed consent from each individual 
participating in this study after adequate explanation of the aims, methods, objectives, and 
potential hazards of the study and before undertaking any study-related procedures. The 
investigator must use the most current IRB / IEC-approved consent form for documenting 
written informed consent. Each informed consent (or assent as applicable) will be appropriately 
signed and dated by the subject or the subject’s legally authorized representative and the person 
conducting the consent discussion, and also by an impartial witness if required by IRB / IEC or
local requirements. The consent form will inform subjects about genomic testing and sample 
retention, and their right to receive clinically relevant genomic analysis results.


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9.1.5.
Confidentiality
The investigator must assure that subjects’ anonymity will be strictly maintained and that their 
identities are protected from unauthorized parties. Only an identification code and any other 
unique identifier(s) as allowed by local law (such as year of birth) will be recorded on any form 
or biological sample submitted to the Sponsor, IRB / IEC, or laboratory. Laboratory specimens 
must be labeled in such a way as to protect subject identity while allowing the results to be 
recorded to the proper subject. Refer to specific laboratory instructions. NOTE: The investigator 
must keep a screening log showing codes, names, and addresses for all subjects screened and for 
all subjects enrolled in the trial. Subject data will be processed in accordance with all applicable 
regulations.
The investigator agrees that all information received from Gilead, including but not limited to the 
investigator brochure, this protocol, eCRF, the study drug, and any other study information, 
remain the sole and exclusive property of Gilead during the conduct of the study and thereafter. 
This information is not to be disclosed to any third party (except employees or agents directly 
involved in the conduct of the study or as required by law) without prior written consent from 
Gilead. The investigator further agrees to take all reasonable precautions to prevent the 
disclosure by any employee or agent of the study site to any third party or otherwise into the 
public domain.
9.1.6.
Study Files and Retention of Records
The investigator must maintain adequate and accurate records to enable the conduct of the study 
to be fully documented and the study data to be subsequently verified. These documents should 
be classified into at least the following two categories: (1) investigator’s study file, and 
(2) subject clinical source documents.
The investigator’s study file will contain the protocol / amendments, eCRF and query forms, 
IRB / IEC and governmental approval with correspondence, informed consent, drug records, 
staff curriculum vitae and authorization forms, and other appropriate documents and 
correspondence.
The required source data should include sequential notes containing at least the following 
information for each subject:

Subject identification (name, date of birth, gender);

Documentation that subject meets eligibility criteria, i.e. history, physical examination, and 
confirmation of diagnosis (to support inclusion and exclusion criteria);

Documentation of the reason(s) a consented subject is not enrolled

Participation in study (including study number);

Study discussed and date of informed consent;


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
Dates of all visits;

Documentation that protocol specific procedures were performed;

Results of efficacy parameters, as required by the protocol;

Start and end date (including dose regimen) of study drug, including dates of dispensing and 
return;

Record of all adverse events and other safety parameters (start and end date, and including 
causality and severity);

Concomitant medication (including start and end date, dose if relevant; dose changes);

Date of study completion and reason for early discontinuation, if it occurs.
All clinical study documents must be retained by the investigator until at least 2 years or 
according to local laws, whichever is longer, after the last approval of a marketing application in 
an ICH region (i.e. United States, Europe, or Japan) and until there are no pending or planned 
marketing applications in an ICH region; or, if no application is filed or if the application is not 
approved for such indication, until 2 years after the investigation is discontinued and regulatory 
authorities have been notified. Investigators may be required to retain documents longer if 
specified by regulatory requirements, by local regulations, or by an agreement with Gilead. The 
investigator must notify Gilead before destroying any clinical study records.
Should the investigator wish to assign the study records to another party or move them to another 
location, Gilead must be notified in advance.
If the investigator cannot provide for this archiving requirement at the study site for any or all of 
the documents, special arrangements must be made between the investigator and Gilead to store 
these records securely away from the site so that they can be returned sealed to the investigator 
in case of an inspection. When source documents are required for the continued care of the 
subject, appropriate copies should be made for storage away from the site.
9.1.7.
Case Report Forms
For each subject consented, an eCRF will be completed by an authorized study staff member 
whose training for this function is documented according to study procedures. eCRF should be 
completed on the day of the subject visit to enable the Sponsor to perform central monitoring of 
safety data. The Eligibility Criteria eCRF should be completed only after all data related to 
eligibility have been received. Subsequent to data entry, a study monitor will perform source data 
verification within the Electronic Data Capture (EDC) system. Original entries as well as any 
changes to data fields will be stored in the audit trail of the system. Prior to database lock (or any 
interim time points as described in the clinical data management plan), the investigator will use 
his / her log in credentials to confirm that the forms have been reviewed, and that the entries 
accurately reflect the information in the source documents. The eCRF capture the data required 


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per the protocol schedule of events and procedures. System-generated or manual queries will be 
issued to the investigative site staff as data discrepancies are identified by the monitor or internal 
Gilead staff, who routinely review the data for completeness, correctness, and consistency. The 
site coordinator is responsible for responding to the queries in a timely manner, within the 
system, either by confirming the data as correct or updating the original entry, and providing the 
reason for the update (e.g. data entry error). At the conclusion of the trial, Gilead will provide the 
site with a read-only archive copy of the data entered by that site. This archive must be stored in 
accordance with the records retention requirements outlined in Section 9.1.6.
9.1.8.
Study Drug Accountability and Return
Where possible, study drug should be destroyed at the site. If the site has an appropriate SOP for 
drug destruction as determined by Gilead, the site may destroy used (empty or partially empty) 
and unused study drug supplies in accordance with that site’s approved SOP. A copy of the site’s 
approved SOP will be obtained for central files. If study drug is destroyed on site, the 
investigator must maintain accurate records for all study drug destroyed. Records must show the 
identification and quantity of each unit destroyed, the method of destruction, and the person who 
disposed of the study drug. Upon study completion, copies of the study drug accountability 
records must be filed at the site. Another copy will be returned to Gilead.
If the site does not have an appropriate SOP for drug destruction, used and unused study drug
supplies are to be sent to the designated disposal facility for eventual destruction. The study 
monitor will provide instructions for return.
9.1.9.
Inspections
The investigator will make available all source documents and other records for this trial to 
Gilead’s appointed study monitors, to IRBs / IECs, or to regulatory authority or health authority 
inspectors.
9.1.10.
Protocol Compliance
The investigator is responsible for ensuring the study is conducted in accordance with the 
procedures and evaluations described in this protocol.
9.2.
Sponsor Responsibilities
9.2.1.
Protocol Modifications
Protocol modifications, except those intended to reduce immediate risk to study subjects, may be 
made only by Gilead. The investigator must submit all protocol modifications to the IRB / IEC in 
accordance with local requirements and receive documented IRB / IEC approval before 
modifications can be implemented.


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9.2.2.
Study Report and Publications
A clinical study report (CSR) will be prepared and provided to regulatory agencies. Gilead will 
ensure that the report meets the standards set out in the ICH Guideline for Structure and Content 
of Clinical Study Reports (ICH E3). NOTE: An abbreviated report may be prepared in certain 
cases. 
Investigators in this study may communicate, orally present, or publish in scientific journals or 
other scholarly media only after the following conditions have been met:

The results of the study in their entirety have been publicly disclosed by or with the consent 
of Gilead in an abstract, manuscript, or presentation form or the study has been completed at 
all study sites for at least 2 years.

The investigator will submit to Gilead any proposed publication or presentation along with 
the respective scientific journal or presentation forum at least 30 days before submission of 
the publication or presentation.

No such communication, presentation, or publication will include Gilead’s confidential 
information (see Section 9.1.5).

The investigator will comply with Gilead’s request to delete references to its confidential 
information (other than the study results) in any paper or presentation and agrees to withhold 
publication or presentation for an additional 60 days in order to obtain patent protection, if 
deemed necessary.
9.3.
Joint Investigator / Sponsor Responsibilities
9.3.1.
Payment Reporting
Investigators and their study staff may be asked to provide services performed under this 
protocol, e.g. attendance at Investigator's Meetings. If required under the applicable statutory and 
regulatory requirements, Gilead will capture and disclose to Federal and State agencies any 
expenses paid or reimbursed for such services, including any clinical trial payments, meal, travel 
expenses or reimbursements, consulting fees, and any other transfer of value.
9.3.2.
Access to Information for Monitoring
In accordance with regulations and guidelines, the study monitor must have direct access to the 
investigator’s source documentation in order to verify the accuracy of the data recorded in the 
eCRF.
The monitor is responsible for routine review of the eCRF at regular intervals throughout the 
study to verify adherence to the protocol and the completeness, consistency, and accuracy of the 
data being entered on them. The monitor should have access to any subject records needed to 
verify the entries on the eCRF. The investigator agrees to cooperate with the monitor to ensure 
that any problems detected through any type of monitoring (central, onsite) are resolved.


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9.3.3.
Access to Information for Auditing or Inspections
Representatives of regulatory authorities or of Gilead may conduct inspections or audits of the 
clinical study. If the investigator is notified of an inspection by a regulatory authority the 
investigator agrees to notify the Gilead Medical Monitor immediately. The investigator agrees to 
provide to representatives of a regulatory agency or Gilead access to records, facilities, and 
personnel for the effective conduct of any inspection or audit.
9.3.4.
Study Discontinuation
Both the Sponsor and the investigator reserve the right to terminate the study at any time. Should 
this be necessary, both parties will arrange discontinuation procedures and notify the appropriate 
regulatory authority(ies), IRBs, and IECs. In terminating the study, Gilead and the investigator 
will assure that adequate consideration is given to the protection of the subjects’ interests.


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10.
REFERENCES
Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 
1976;16:31-41.
Genovese MC, Kalunian KC, Walker D, Gottenberg JE, De Vlam K, Mozaffarian N, et al. Safety 
and Efficacy of Filgotinib in a Phase 3 Trial of Patients with Active Rheumatoid 
Arthritis and Inadequate Response or Intolerance to Biologic Dmards [Abstract 
No. L06]. ACR/ARHP Annual Meeting; 2018 19-24 October; Chicago, IL. 
Gladman D, Rigby W, Azevedo VF, Behrens F, Blanco R, Kaszuba A, et al. Tofacitinib for 
Psoriatic Arthritis in Patients with an Inadequate Response to TNF Inhibitors. N 
Engl J Med 2017;377 (16):1525-36.
Gladman DD, Antoni C, Mease P, Clegg DO, Nash P. Psoriatic arthritis: epidemiology, clinical 
features, course, and outcome. Annals of the rheumatic diseases 2005;64 Suppl 
2:ii14-7.
Gladman DD, Mease PJ, Ritchlin CT, Choy EH, Sharp JT, Ory PA, et al. Adalimumab for long-
term treatment of psoriatic arthritis: forty-eight week data from the adalimumab 
effectiveness in psoriatic arthritis trial. Arthritis Rheum 2007;56 (2):476-88.
Gossec L, Smolen JS, Gaujoux-Viala C, Ash Z, Marzo-Ortega H, van der Heijde D, et al. 
European League Against Rheumatism recommendations for the management of 
psoriatic arthritis with pharmacological therapies. Annals of the rheumatic 
diseases 2012;71 (1):4-12.
Koch GG, Tangen CM. Nonparametric Analysis of Covariance and Its Role in Noninferiority 
Clinical Trials. Drug Information Journal 1999;33:1145-59.
Liu JT, Tzeng CS, Tsou HH. Establishing Non-Inferiority of a New Treatment in a Three-Arm 
Trial: Apply a Step-Down Hierarchical Model in a Papulopustular Acne Study
and an Oral Prophylactic Antibiotics Study. International Journal of Statistics in 
Med Research 2014;3 (1):11-20.
Mease P. Psoriatic arthritis and spondyloarthritis assessment and management update. Current 
opinion in rheumatology 2013;25 (3):287-96.
Mease P, Coates LC, Helliwell PS, Stanislavchuk M, Rychlewska-Hanczewska A, Dudek A, et 
al. Efficacy and Safety of Filgotinib, a Selective Januse Kinase 1 Inhibitor, in 
Patients with Active Psoriatic Arthritis (EQUATOR): Results from a 
Randomized, Placebo-Controlled Phase 2 Trial. Lancet 2018;392:2367-77.


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Mease P, Hall S, FitzGerald O, van der Heijde D, Merola JF, Avila-Zapata F, et al. Tofacitinib or 
Adalimumab versus Placebo for Psoriatic Arthritis. N Engl J Med 2017a;377 
(16):1537-50.
Mease P, Hall S, FitzGerald O, van der Heijde D, Merola JF, Avila-Zapata F, et al. Tofacitinib or 
Adalimumab versus Placebo for Psoriatic Arthritis [Supplementary Appendix]. N 
Engl J Med 2017b;377 (16):1537-50.
Mease PJ, Kivitz AJ, Burch FX, Siegel EL, Cohen SB, Ory P, et al. Continued inhibition of 
radiographic progression in patients with psoriatic arthritis following 2 years of 
treatment with etanercept. The Journal of rheumatology 2006;33 (4):712-21.
Namour F, Diderichsen PM, Cox E, Vayssiere B, Van der Aa A, Tasset C, et al. 
Pharmacokinetics and Pharmacokinetic/Pharmacodynamic Modeling of Filgotinib 
(GLPG0634), a Selective JAK1 Inhibitor, in Support of Phase IIB Dose Selection. 
Clin Pharmacokinet 2015;54 (8):859-74.
O'Shea JJ, Notarangelo LD, Johnston JA, Candotti F. Advances in the understanding of cytokine 
signal transduction: the role of Jaks and STATs in immunoregulation and the 
pathogenesis of immunodeficiency. Journal of clinical immunology 1997;17 
(6):431-47.
Ritchlin CT, Colbert RA, Gladman DD. Psoriatic Arthritis. N Engl J Med 2017;376 (10):957-70.
Ritchlin CT, Krueger JG. New Therapies for Psoriasis and Psoriatic Arthritis [Author 
Manuscript]. Current opinion in rheumatology 2016;28 (3):204-10.
van der Heijde D, Baraliakos X, Gensler LS, Maksymowych WP, Tseluyko V, Nadashkevich O, 
et al. Efficacy and Safety of Filgotinib, a Selective Janus Kinase 1 Inhibitor, in 
Patients with Active Ankylosing Spondylitis (TORTUGA): Results from a 
Randomized Placebo-Controlled, Phase 2 Trial. Lancet 2018;392:2378–87.


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Final 
Amendment2 
11. 
APPENDICES 
Appendix I. 
Appendix 2. 
Appendix 3. 
Appendix 4. 
Appendix 5. 
Appendix 6. 
Appendix 7. 
Appendix 8. 
Appendix 9. 
Appendix I 0. 
Appendix 11. 
A 
endix 12. 
Appen 1x 17. 
Appendix 18. 
Appendix 19. 
Appendix 20. 
Appendix 2 1. 
Appendix 22. 
Appendix 23. 
Appendix 24. 
Appendix 25. 
Appendix 26. 
CONFIDENTIAL 
Investigator Signature Page 
Study Procedures Table 
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements 
Management of Clinical and Laboratory Adverse Events 
Laboratory Assessment Table 
Primmy and Key Secondary Null Hypotheses 
Hypothesis Testing Strategy 
Protocol, Day Numbering 
HAQ-DI: Health Assessment Questionnaire - Disability Index 
FACIT-Fatigue: Functional Assessment of Chronic Illness Therapy -Fatigue Scale 
SF-36v2: 36-Item Short-Fotm Health Survey Version 2 
PsAI D-12: 12-item Psoriatic Arthritis Im act of Disease uestionnaire 
o a Assessment o Disease Activity 
PGAPI: Patient's Global Assessment of Psoriatic Arthritis Pain Intensity 
CASPAR: Classification Criteria for Psoriatic Arthritis 
PASI including BSA: Psoriasis Area and Severity Index including Body Surface 
Area 
mNAPSI: Modified Nail Psoriasis Severity Index 
PhGAP: Physician's Global Assessment of Psoriasis 
SPARCC Enthesitis Index and LEI: Spondyloarthritis Research Consortium of 
Canada Enthesitis Index and Leeds Enthesitis Index 
SJC66 I TJC68: Swollen and Tender Joint Count 
LOI: Leeds Dactylitis Index 
PhGADA: Physician's Global Assessment of Disease Activity 
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Appendix 1.
Investigator Signature Page
GILEAD SCIENCES, INC.
333 LAKESIDE DRIVE
FOSTER CITY, CA 94404, USA
STUDY ACKNOWLEDGEMENT
PENGUIN 1: A Phase 3, Randomized, Double blind, Placebo and Adalimumab-controlled Study 
to Evaluate the Efficacy and Safety of Filgotinib in Subjects with Active Psoriatic Arthritis Who 
Are Naïve to Biologic DMARD Therapy
GS-US-431-4566, Amendment 2, 17 April 2020
This protocol has been approved by Gilead Sciences, Inc. The following signature documents 
this approval.
Name (Printed)
Author
Signature
Date
INVESTIGATOR STATEMENT
I have read the protocol, including all appendices, and I agree that it contains all necessary 
details for me and my staff to conduct this study as described. I will conduct this study as 
outlined herein and will make a reasonable effort to complete the study within the time 
designated.
I will provide all study personnel under my supervision copies of the protocol and access to all 
information provided by Gilead Sciences, Inc. I will discuss this material with them to ensure 
that they are fully informed about the drugs and the study.
Principal Investigator Name (Printed)
Signature
Date
Site Number
04/20/2020
PPD
PPD


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Appendix 2.
Study Procedures Table
EVENT
Part 1: Main Study
Visit (±window)
Screen
(-28 days to 0)
Day 1
Weeks (±3 days)
ET
(±7 days)
Safety 
Follow-up
(±7 days) a
2
4
8
12
16
Screening Assessments
Informed consent
X
Inclusion / Exclusion Criteria
X
X b
Demographics, Baseline / Disease 
Characteristics, PsA Diagnosis and 
Prior PsA Treatment, Medical 
History
X
Complete Physical Examination
X
TB Screening and Chest X-ray
X
Patient Reported Outcomes
HAQ-DI: Health Assessment 
Questionnaire – Disability Index 
X
X
X
X
X
X
X
FACIT-Fatigue: Functional 
Assessment of Chronic Illness 
Therapy – Fatigue Scale
X
X
X
X
SF-36v2: 36-item Short-Form Health 
Survey Version 2
X
X
X
X
PsAID-12: 12-item Psoriatic Arthritis 
Impact of Disease
X
X
X
X
PGADA: Patient’s Global 
Assessment of Disease Activity
X
X
X
X
X
X
X
PGAPI: Patient's Global Assessment 
of Psoriatic Arthritis Pain Intensity
X
X
X
X
X
X
X
CCI
CCI
CCI
CCI


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EVENT
Part 1: Main Study
Visit (±window)
Screen
(-28 days to 0)
Day 1
Weeks (±3 days)
ET
(±7 days)
Safety 
Follow-up
(±7 days) a
2
4
8
12
16
Physician Reported Outcomes
CASPAR: Classification Criteria for 
Psoriatic Arthritis
X
PASI including BSA: Psoriasis Area 
and Severity Index including Body 
Surface Area
X
X
X
X
X
X
mNAPSI: Modified Nail Psoriasis 
Severity Index
X
X
X
X
X
X
PhGAP: Physician’s Global 
Assessment of Psoriasis 
X
X
X
X
X
X
X
SPARCC Enthesitis Index and LEI: 
Spondyloarthritis Research 
Consortium of Canada Enthesitis 
Index and Leeds Enthesitis Index
X
X
X
X
X
X
SJC66 / TJC68: Swollen and Tender 
Joint Count
X
X
X
X
X
X
X
X
LDI: Leeds Dactylitis Index
X
X
X
X
X
X
PhGADA: Physician’s Global 
Assessment of Disease Activity
X
X
X
X
X
X
X
Safety
Vital Signs and Weight
X
X
X
X
X
X
X
X
Symptom-Driven Physical 
Examination
X
X
X
X
X
X
X
12-Lead ECG
X
Pregnancy Test c
X
X
X
X
X
X
X
X
X


Filgotinib 
Protocol GS-US-431-4566 
Gilead Sciences, Inc. 
EVENT 
Visit (±window) 
Hematology and Chemistry 
Urinalysis 
Endocrine: FSJ-1, TSH, and HbA I c d 
Lipid profile (fasting) 
SemmCRP' 
Screen 
(-28 days to 0) 
Day 1 
2 
X 
X 
X 
X 
X 
X 
X 
X 
Part 1: Main Study 
Weeks (±3 days) 
ET 
4 
8 
12 
16 
(±7 days) 
X 
X 
X 
X 
X 
X 
x• 
X 
X 
X 
X 
X 
~ - - - - - - - -
~--------------------------------------
Biomarker Samples r 
X 
X 
X 
X 
X 
Viral Serologyi 
X 
Viral Monitoring k 
X 
x• 
L____ ___________________ _ 
L____ 
--------------------------------------
e.o 
C: 
'@i 
MRI ' 
xm 
X 
"' 
.§ 
Adverse Events 
X 
X 
X 
X 
X 
X 
X 
X 
Concomitant Medications 
X 
X 
X 
X 
X 
X 
X 
X 
Study Drng(s) Dispensation 
X 
x• 
X 
X 
X 
X 
Self-injection (or caregiver) Training 0 
X 
CONFIDENTIAL 
Page 98 
Final 
Amendment2 
Safety 
Follow-up 
(±7 days)• 
X 
X 
17 April 2020 


Filgotinib 
Protocol GS-US-431-4566 
Gilead Sciences, Inc. 
Final 
Amendment2 
a 
Subjects in Europe will have additional Safety Follow-up Visits. These visits will occur 8, 12, and 16 weeks after their last SC injection of study dmg and should also be done 
by phone call unless otherwise re.quired by region. If the subject's last study visit is greater than or equal to 16 weeks from their last SC injection, the additional Safety 
Follow-up Visits will not be re.quired. 
b 
Eligibility criteria check based on: ( I) laboratory results from the Screening Visit, (2) SJC / TJC at Screening and Day I, and (3) urine pregnancy test at Day I for 
female subjects of childbearing potential. 
c 
For eligibility, a semm pregnancy test will be perfom1ed at the Screening Visit and a urine pregnancy test will be perfom1ed at the Day I Visit. Urine pregnancy tests will be 
perfom1ed at all other visits. Subjects will be provided at home pregnancy tests for use during the LTE, at the Safety Follow-up Visit, or as needed. Per local regulations, 
LTE and Safety Follow-up Visit pregnancy tests may be perfom1ed in clinic. 
d 
Investigator and the Sponsor may re-evaluate a subject's childbearing potential during the study (including the use of FSI-1 values if appropriate) 
e 
Iflast assessment was completed < I I weeks previously, do not perfom1 at the ET Visit. 
f 
Biomarker samples should be collected prior to study dmg administration. Subjects and Investigators will be kept blinded to the results of the CRP test at all visits. Sponsor 
will be blinded to CRP results in the Main Study only, except the Day I Visit. T and B lymphocyte and natural killer (TBNK) results will be blinded to subjects and 
I 
Investigators at all visits, and will be collected at Da I and Week 16. PBMC North America onl 
collection on Da I, Week 4, and Week 16. 
r 
j 
Hepatitis B surface Ag and core Ab, re ex Hepatitis B DNA (as needed), Hepatitis C Ab, re ex Hepatitis C RNA (as needed), HIV 1 and 2 at the Screening Visit. 
k 
Viral monitoring for HBV or I-ICY, as applicable. 
I 
Imaging perfom1ed after enrollment may be done within ±7 days of the scheduled visit. 
m 
Screening MRI to be perfom1ed only after a subject has fulfilled criteria for entry to the Main Study. The Week 16 Visit MRI is to be perfom1ed only if a Screening MRI is 
acceptable per central imaging. 
n 
Dmg dispensation at Week 2 is for "floater" study dmg supply. Please reference your pham1acy manual for instmctions on handling floater study dmg. 
o 
Self-injection or caregiver training will occur at Day I and can be repeated, as needed. 
CONFIDENTIAL 
Page 99 
17 April 2020 


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Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 100
17 April 2020
EVENT
Part 2: Long Term Extension
Visit (±window)
Weeks (±3 days)
Weeks (±7 days)
Completion
Week 120
(±7 days)
ET
(±7 days)
Safety 
Follow-up
(±7 days) a
18
20
24
28
36
48
60
72
84
96
108
Patient Reported Outcomes
HAQ-DI: Health 
Assessment 
Questionnaire –
Disability Index 
X
X
X
X
X
X
X
X
X
X
X
X
X
FACIT-Fatigue: 
Functional Assessment 
of Chronic Illness 
Therapy – Fatigue Scale
X
X
X
X
SF-36v2: 36-item 
Short-Form Health 
Survey Version 2
X
X
X
X
PsAID-12: 12-item 
Psoriatic Arthritis 
Impact of Disease 
Questionnaire
X
X
X
X
PGADA: Patient’s 
Global Assessment of 
Disease Activity
X
X
X
X
X
X
X
X
X
X
X
X
X
PGAPI: Patient’s Global 
Assessment of Psoriatic 
Arthritis Pain Intensity
X
X
X
X
X
X
X
X
X
X
X
X
X
CCI
CCI


Filgotinib
Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 101
17 April 2020
EVENT
Part 2: Long Term Extension
Visit (±window)
Weeks (±3 days)
Weeks (±7 days)
Completion
Week 120
(±7 days)
ET
(±7 days)
Safety 
Follow-up
(±7 days) a
18
20
24
28
36
48
60
72
84
96
108
Physician Reported Outcomes a
PASI including BSA: 
Psoriasis Area and 
Severity Index including 
Body Surface Area
X
X
X
X
X
X
X
X
X
mNAPSI: Modified Nail 
Psoriasis Severity Index
X
X
X
X
X
X
X
X
X
PhGAP: Physician’s 
Global Assessment of 
Psoriasis
X
X
X
X
X
X
X
X
X
X
SPARCC Enthesitis 
Index and LEI: 
Spondyloarthritis 
Research Consortium of 
Canada Enthesitis Index 
and Leeds Enthesitis 
Index
X
X
X
X
X
X
X
X
X
SJC66 / TJC68: Swollen 
and Tender Joint Count
X
X
X
X
X
X
X
X
X
X
X
X
X
LDI: Leeds Dactylitis 
Index 
X
X
X
X
X
X
X
X
X
PhGADA: Physician’s 
Global Assessment of 
Disease Activity
X
X
X
X
X
X
X
X
X
X
X
X
X
Safety
Complete Physical 
Examination
X
X
X
X
Symptom-Driven 
Physical Examination
X
X
X
X
X
X
X
X
X
Vital Signs and Weight
X
X
X
X
X
X
X
X
X
X
X
X
X
TB Screening and Chest 
X-ray
X
X
X b
Pregnancy Test (in 
clinic)
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Pregnancy Test 
(at home) c
X
X


Filgotinib
Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 102
17 April 2020
EVENT
Part 2: Long Term Extension
Visit (±window)
Weeks (±3 days)
Weeks (±7 days)
Completion
Week 120
(±7 days)
ET
(±7 days)
Safety 
Follow-up
(±7 days) a
18
20
24
28
36
48
60
72
84
96
108
Laboratory
Hematology and 
Chemistry
X
X
X
X
X
X
X
X
X
X
X
X
X
Lipid profile (fasting)
X
X
X
X b
Serum CRP d
X
X
X
X
X
X
X
X
X
X
X
X
X
Biomarker Samples d
X
X
X
Viral Monitoring e
X
X
X
X
X
X
X
X
X
X f
Endocrine: FSH g
X
Adverse Events
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Concomitant Medications
X
X
X
X
X
X
X
X
X
X
X
X
X
Study Drug(s) Dispensation
X
X
X
X
X
X
X
X
X
X
a
Subjects in Europe will have additional Safety Follow-up Visits. These visits will occur 8, 12, and 16 weeks after their last SC injection of study drug and should also be done 
by phone call unless otherwise required by region. If the subject’s last study visit is greater than or equal to 16 weeks from their last SC injection, the additional Safety 
Follow-up Visits will not be required.
b
If last assessment was completed <47 weeks previously, do not perform at the ET Visit.
c
For female subjects of childbearing potential only. The site will call the subject every 4 weeks during the LTE or at the Safety Follow-up Visit, if there is not a clinic visit 
scheduled, in order to obtain results. Per local regulations, at home pregnancy tests may be performed in clinic.
d
Biomarker samples should be collected prior to study drug administration. Subjects and Investigators will be kept blinded to the results of the CRP test at all visits. T and 
B lymphocyte and natural killer (TBNK) results will be blinded to subjects and Investigators at all visits, and will be collected at Week 48, Week 96, and Week 120. PBMC
(North America only) collection on Week 48, Week 96, and Week 120.
e
Viral monitoring for HBV or HCV, as applicable.
f
If last assessment was completed <11 weeks previously, do not perform at the ET Visit.
g
Investigator and the Sponsor may re-evaluate a subject’s childbearing potential during the study (including the use of FSH values if appropriate).


Filgotinib
Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 103
17 April 2020
Appendix 3.
Pregnancy Precautions, Definition for Female of Childbearing 
Potential, and Contraceptive Requirements
The administration of filgotinib in embryo-fetal animal development studies resulted in 
decreased numbers of viable rat fetuses, increased resorptions, and visceral and skeletal 
malformations. Similar effects were noted in the rabbit. A safety margin relative to human 
exposure has not been identified. Pregnancy is contraindicated during use of filgotinib.
For participation in this study, all subjects of childbearing potential must agree to the use of 
highly effective contraception as outlined below.
In addition, women of childbearing potential should have a urine pregnancy test every 4 weeks 
during the study.
1) Definitions
a. Definition of Childbearing Potential
For the purposes of this study, a female born subject is considered of childbearing potential 
following the initiation of puberty (Tanner stage 2) until becoming post-menopausal, unless 
permanently sterile or with medically documented ovarian failure.
Women are considered to be in a postmenopausal state when they are >54 years of age with 
cessation of previously occurring menses for >12 months without an alternative cause. In 
addition, women of any age with amenorrhea of >12 months may also be considered 
postmenopausal if their follicle stimulating hormone (FSH) level is in the postmenopausal range 
(as defined by central laboratory reference ranges) and they are not using hormonal 
contraception or hormonal replacement therapy.
Permanent sterilization includes hysterectomy, bilateral oophorectomy, or bilateral 
salpingectomy in a female subject of any age. Bilateral tubal ligation is not considered 
permanent sterilization. Women who do not meet below criteria for being post-menopausal, are 
not permanently sterile, or do not have medically documented ovarian failure must have 
pregnancy testing as outlined by the protocol.
Investigator and the Sponsor may re-evaluate a subject’s childbearing potential during the study 
(including the use of FSH values if appropriate).
b. Definition of Male Fertility
For the purposes of this study, a male born subject is considered fertile after the initiation of 
puberty unless permanently sterile by bilateral orchidectomy or medical documentation of 
permanent male infertility. Vasectomy alone is not considered permanent sterilization.


Filgotinib
Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 104
17 April 2020
2) Contraception Requirements for Female Subjects
a. Study Drug Effects on Pregnancy and Hormonal Contraception
Filgotinib is contraindicated in pregnancy as there is a possibility of human 
teratogenicity / fetotoxicity in early pregnancy based on non-clinical data. Data from a drug-drug 
interaction study of filgotinib and hormonal contraceptives demonstrated that filgotinib does not 
alter the pharmacokinetics of representative hormonal contraceptives levonorgestrel / ethinyl 
estradiol. For male subjects, male condom should be used; for their female partners of 
childbearing potential, an accepted contraceptive method should also be considered. Details are 
outlined below.
Please refer to the latest version of the filgotinib investigator’s brochure for additional 
information.
b. Contraception for Female Subjects of Childbearing Potential
The inclusion of female subjects of childbearing potential requires the use of highly effective 
contraceptive measures. Women must have a negative serum pregnancy test at Screening and a 
negative urine pregnancy test on the Day 1 Visit prior to randomization. Pregnancy tests will be 
performed at monthly intervals thereafter. In the event of a delayed menstrual period 
(>one month between menstruations), a pregnancy test must be performed to rule out pregnancy. 
This is true even for women of childbearing potential with infrequent or irregular periods. 
Female subjects of childbearing potential must agree to use one of the contraceptive methods 
below from Screening until either 35 days following the last dose of oral study drug or the 
contraception duration specified in the local adalimumab (HUMIRA®) label following the last 
dose of injected study drug (whichever is later).

Complete abstinence from intercourse of reproductive potential (e.g. heterosexual 
intercourse). Abstinence is an acceptable method of contraception only when it is in line with 
the subject’s preferred and usual lifestyle.
Or

Consistent and correct use of 1 of the following methods of birth control listed below
(as approved and available per local standards):
Intrauterine device (IUD) with a failure rate of <1% per year
Tubal sterilization
Essure micro-insert system (provided confirmation of success 3 months after procedure)
(Not approved in Japan)
Vasectomy in the male partner (provided that the partner is the sole sexual partner and 
had confirmation of surgical success at least 3 months after procedure, with 
documentation of sperm-free ejaculate)


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Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
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These above described methods are considered preferred methods of highly effective 
contraception in this protocol.
Female subjects who wish to use a hormonally based method must agree to use it in conjunction 
with a barrier method (used either by the female subject or by her male partner). Female subjects 
who utilize a hormonal contraceptive as one of their birth control methods must have 
consistently used the same method for at least three months prior to study dosing. 
Hormonally-based contraceptives and barrier methods permitted for use in this protocol are as 
follows:

Hormonal methods (subject must agree to use with a barrier method, preferably, with a 
male condom)
Oral contraceptives (either combined estrogen / progestin or progesterone only)
Injectable progesterone (Not approved in Japan)
Subdermal Implants of levonorgestrel (Not approved in Japan)
Transdermal contraceptive patch (Not approved in Japan)
Contraceptive vaginal ring

Barrier methods (subject must agree to use with a hormonal method)
Male or female condom (with or without spermicide)
Diaphragm with spermicide (Not approved in Japan)
Cervical cap with spermicide (Not approved in Japan)
Sponge with spermicide (Not approved in Japan)
All female subjects must also agree to refrain from egg donation and in vitro fertilization during 
study participation and until either 35 days following the last dose of oral study drug or the 
contraception duration specified in the local adalimumab (HUMIRA®) label following the last 
dose of injected study drug (whichever is later).
3) Contraception Requirements for Male Subjects
It is theoretically possible that a relevant systemic concentration may be achieved in a female 
partner from exposure to the male subject’s seminal fluid. Therefore, male subjects with female 
partners of childbearing potential must agree to use condoms during study participation and for 
90 days after the last study drug dose. Female partners of male study subjects should consider 
using one of the above methods of contraception as well. Male subjects must also agree to refrain 
from sperm donation during treatment and until at least 90 days after the end of dosing.


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Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 106
17 April 2020
4) Unacceptable Birth Control Methods
Birth control methods that are unacceptable include periodic abstinence (e.g. calendar, ovulation, 
symptothermal, post-ovulation methods), withdrawal (coitus interruptus), spermicides only, and 
lactational amenorrhea method (LAM). Female condom and male condom should not be used 
together.
5) Procedures to be Followed in the Event of Pregnancy
Subjects will be instructed to notify the investigator if they become pregnant at any time during 
the study, or if they become pregnant within 35 days of last study drug dose. Subjects who 
become pregnant or who suspect that they are pregnant during the study must report the 
information to the investigator and discontinue all the study drugs immediately. These subjects 
will be asked to continue in the study without taking study drug through the completion of the 
main study. Male subjects whose partner has become pregnant or suspects she is pregnant during 
the study or up to 90 days after the last dose of study drug are to report the information to the 
investigator.
Instructions for reporting pregnancy, partner pregnancy, and pregnancy outcome are outlined in 
Section 7.7.2.1.
6) Pregnancy Testing
All females of childbearing potential will have urine pregnancy testing every 4 weeks during the 
dosing period through the Safety Follow-up Visit (28-35 days after their last dose of study drug). 
During the periods where study visits are every 6-8 weeks, women should continue to have 
pregnancy tests every 4 weeks, using home pregnancy urine tests that will be provided to them. 
The site will call the subject every 4 weeks to obtain results of these pregnancy tests and will 
record the information in the source documents and eCRF. If a positive urine pregnancy test is 
reported, the subject will be asked to return to the clinic for a confirmatory serum pregnancy test.


Filgotinib 
Protocol GS-US-431-4566 
Final 
Gilead Sciences, Inc. 
Amendment 2 
Appendix 4. 
Management of Clinical and Laboratory Adverse Events 
Grade I 
Grade 2 
Grade 3 
Grade 4 
' 
May continue dosing at the 
discretion of the investigator 
Repeat lab to confirm 
toxicity 
Repeat lab to confim1 
toxicity 
' 
If confim1ed and possibly and/or probably related to 
study drugs: 
I. Withhold study drugs until SGrade 2 
2. Restart all study drugs at full dose 
', 
If confirmed and unrelated 
to study drugs, dosing may 
continue at the discretion of 
the investigator 
II 
If Grade 3 or 4 recurrence that is confirmed and 
possibly or probably related to study drugs, 
discontinue all study drugs dosing permanently 
If Grade 3 or 4 recurrence that is considered unrelated 
to study drugs, continue all study drugs at the same 
dose at the discretion of the investigator 
For study specific interruption and stopping criteria, please refer to Section 3.5. 
CONFIDENTIAL 
Page 107 
If confirmed and possibly or 
probably related to study 
drugs, discontinue study 
drugs dosing permanently 
and follow at periodic 
intervals at least we-ekly until 
a return to baseline or is 
otherwise explained 
17 April 2020 


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Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 108
17 April 2020
Appendix 5.
Laboratory Assessment Table
Hematology
Chemistry
Urinalysis
Other
Hematocrit
Hemoglobin
Platelet count
Red blood cell (RBC) 
count
Red blood cell indices:
RBC Morphology and 
MCV
MCH
MCHC
White blood cell (WBC) 
count
Differentials (absolute 
and percentage), 
including:
Lymphocytes
Monocytes
Neutrophils
Eosinophils
Basophils
Alkaline phosphatase
Aspartate aminotransferase (AST)
Alanine aminotransferase (ALT)
Gamma-glutamyl transpeptidase 
(GGT)
Total bilirubin
Direct and indirect bilirubin
Total protein
Albumin
Bicarbonate
Blood urea nitrogen (BUN)
Calcium
Chloride
Serum creatinine*
Glucose
Phosphorus
Magnesium
Potassium
Sodium
Amylase
Lipase 
Lipid profile (fasting): 
Triglycerides
Cholesterol and its subfractions 
(high-density lipoprotein [HDL] 
and low-density lipoprotein [LDL])
Appearance
Blood
Color
Glucose
Specific gravity 
Nitrites
Leukocyte esterase
pH
Protein
Urobilinogen
Reflex to microscopic 
urinalysis if dipstick 
result is abnormal.
Urine drug screen 
Leukocyte subsets 
(TBNK blinded to 
subjects and 
investigators)
vfPBMC**
C-reactive protein 
(hsCRP) (blinded to 
subjects and investigators
for all visits, blinded to 
Sponsor for all Main 
Study visits except Day 1 
Visit)
QuantiFERON®- TB 
GOLD Plus††
Endocrine at screening 
only
Serology
Pregnancy
Hemoglobin A1c
TSH
FSH (for women only)†††
Hepatitis BsAg and 
core Ab (if positive 
core Ab, then reflex 
Hep B DNA)
Hepatitis C Ab 
(if positive, then 
reflex HCV RNA)
HIV
In females of 
childbearing potential:
Serum β-hCG 
(Screening and if 
positive urine β-hCG)
Urine β-hCG (all other 
visits)†
*
Creatinine clearance is calculated by the Cockcroft-Gault equation {Cockcroft 1976} using actual body weight (BW).
Male:
CLcr (mL / min) =
Female: CLcr (mL / min) =
**
vfPBMCs collected in North America only. 
†
During the periods where study visits are every 6-8 weeks, women should continue to have pregnancy tests every 4 weeks,
using home pregnancy urine tests that will be provided to them. The site will call the subject every 4 weeks to obtain results 
of these pregnancy tests and will record the information in the source documents and eCRF.
††
In the event QuantiFERON®-TB GOLD Plus is not available, an equivalent TB test may be substituted by the central lab.
††† Investigator and the Sponsor may re-evaluate a subject’s childbearing potential during the study (including the use of FSH 
values if appropriate).
CCI
[140 - age (years)] x BW(kg) 
72 x [Serum Creatinine (in 1~ ~ ) } 
[140 - age (years)]x BW(kg) x 0.85 
72 x [Serum Creatinine (in 1~~)} 
-


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Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 109
17 April 2020
Appendix 6.
Primary and Key Secondary Null Hypotheses
The primary null hypotheses to be tested are:
H1: 
Filgotinib 200 mg is not different to placebo based on the response rate of ACR20 at 
Week 12
H2: 
Filgotinib 100 mg is not different to placebo based on the response rate of ACR20 at 
Week 12
Hypotheses on the key secondary endpoints will only be tested if the primary hypothesis H1 or 
H2 on that dosing regimen is rejected. The following list is the full list of all the null hypotheses 
on the key secondary endpoints to be tested. The order of the key secondary null hypotheses to 
be tested will be specified in the SAP and is not reflected below.
H3: 
Filgotinib 200 mg is not different to placebo based on the response rate of ACR50 at 
Week 12
H4: 
Filgotinib 100 mg is not different to placebo based on the response rate of ACR50 at 
Week 12
H5: 
Filgotinib 200 mg is not different to placebo based on the change from Baseline in 
HAQ-DI at Week 12
H6: 
Filgotinib 100 mg is not different to placebo based on the change from Baseline in 
HAQ-DI at Week 12
H7: 
Filgotinib 200 mg is not different to placebo based on the change from Baseline in 
SF-36v2 PCS at Week 16
H8: 
Filgotinib 100 mg is not different to placebo based on the change from Baseline in 
SF-36v2 PCS at Week 16
H9: 
Filgotinib 200 mg is not different to placebo based on the change from Baseline in LEI at 
Week 16, in subjects with enthesitis at Baseline
H10: Filgotinib 100 mg is not different to placebo based on the change from Baseline in LEI at 
Week 16, in subjects with enthesitis at Baseline
H11: Filgotinib 200 mg is not different to placebo based on the response rate of PASI75 at 
Week 16, in subjects with psoriasis covering ≥3% of the BSA at Baseline
H12: Filgotinib 100 mg is not different to placebo based on the response rate of PASI75 at 
Week 16, in subjects with psoriasis covering ≥3% of the BSA at Baseline
H13: Filgotinib 200 mg is not different to placebo based on the response rate of MDA at 
Week 16


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Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
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H14: Filgotinib 100 mg is not different to placebo based on the response rate of MDA at 
Week 16
H15: Filgotinib 200 mg preserves no more than 50% of the effect of adalimumab (as compared 
to placebo) on the response rate of ACR20 at Week 12
H16: Filgotinib 100 mg preserves no more than 50% of the effect of adalimumab (as compared 
to placebo) on the response rate of ACR20 at Week 12
H17: Filgotinib 200 mg is not different to placebo based on the change from Baseline in 
FACIT-Fatigue at Week 16
H18: Filgotinib 100 mg is not different to placebo based on the change from Baseline in 
FACIT-Fatigue at Week 16
H19: Filgotinib 200 mg is not different to placebo based on the change from Baseline in LDI at 
Week 16, in subjects with dactylitis at Baseline
H20: Filgotinib 100 mg is not different to placebo based on the change from Baseline in LDI at 
Week 16, in subjects with dactylitis at Baseline


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Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 111
17 April 2020
Appendix 7.
Hypothesis Testing Strategy
Note: Below figure is for illustration purpose and does not reflect the order of key secondary 
hypotheses.


Filgotinib
Protocol GS-US-431-4566
Final
Gilead Sciences, Inc. 
Amendment 2
CONFIDENTIAL
Page 112
17 April 2020
Appendix 8.
Protocol, Day Numbering
Protocol
Day Numbering
# Calendar
Days after Day 1
Example Visit Date
Start of 1st Week
Monday
Day 1
-
16-Sep-19
Tuesday
Day 2
1
17- Sep-19
Wednesday
Day 3
2
18- Sep-19
Thursday
Day 4
3
19- Sep-19
Friday
Day 5
4
20-Sep-19
Saturday
Day 6
5
21-Sep-19
Sunday
Day 7
6
22-Sep-19
Start of 2nd Week
Monday
Day 8
7
23-Sep-19
Tuesday
Day 9
8
24-Sep-19
Wednesday
Day 10
9
25-Sep-19
Thursday
Day 11
10
26-Sep-19
Friday
Day 12
11
27-Sep-19
Saturday
Day 13
12
28-Sep-19
Sunday
Day 14
13
29-Sep-19
Start of 3rd Week
Monday
Day 15
14
30-Sep-19
Tuesday
Day 16
15
1-Oct-19
Wednesday
Day 17
16
2-Oct-19
Thursday
Day 18
17
3-Oct-19
Friday
Day 19
18
4-Oct-19
Saturday
Day 20
19
5-Oct-19
Sunday
Day 21
20
6-Oct-19
NOTE: Vendors may have different Day Numbering (i.e. start with Day 0); however, the # Calendar Days after Day 1 will 
remain consistent.


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Appendix 9.
HAQ-DI: Health Assessment Questionnaire – Disability Index
HEAL TH ASSESSMENT QUEST1IONNAIRE 
Na.me ________________ _ 
Da.te. ________________ _ 
hn th.is section "We are in1te,rested in learning how your illness affects yo1.1r ability to funciicn in daity life. Please feel free to 
add any oomments on the back of !his. page. 
P•lease check the ,response Which best describes your UiSucal abilit~s OVER THE PAST WEEK: 
DRESS'ING & GROOMIN.G 
Are you able to: 
- Dress yourself. including tyl n,g shoelaces amt doing, 
builoos? 
- Slhampoo your h:air? 
ARISING 
Are you able to: 
- Stand up from e straight chair? 
- Get m and out of bed? 
EATING 
Are you able to: 
- Cut your meat? 
- Lift a fu J cup• o:r g)a,s-s to, your m oulh? 
- Open a• n e-.v mi'lk carton? 
W'Ali<ING 
Pde you able to: 
- Wa[k outdoors •Dll flat groum:I? 
- CFJm'b up five steps? 
W [1hou 
.ANY 
Difficulty 
Wim 
SOME 
Difficulty 
P 1tease check any AIDS OR DEVICES that you usually use for a:ny of these acfiviti:es: 
1Mth 
MUCH 
Diffreutty 
Cane 
__ DeVaices used fur dressing (button hook • . zipper pull. 
Walker 
Crutches 
Whee!ch,sfr 
cmg-ha:ndled stioe horn, etc.) 
__ Built up or special utel'l!siFs 
__ Special or buil:t up clhair 
__ 01he.r (Specify: _________ 
Please checlt an,y ca-tegn·ries for which you usllilally need HELP FROM AN.OT!HBR PERSON.: 
__ Oress,ng and Gro<>111ing 
__ Arits.ing 
__ EaUng 
__ Walking 
UNABLE 
To Do 
PATI<EY# __ 
~UES;O,.T I 
HAQAD 
N 
QUESTYPE __ 
PMSVIS ___ 
_ 
RASTUDY __ 
_ 
QUESTISruM __ 
DRf'SSNEW __ 
RISIENE'lll __ _ 
EATNEW ___ -; 
WAU<NEW __ 
_ 
ORSGASST _ 
RISEAS5T __ _ 
EATASST 
WAUO\SSl 
'1;!Slanfurd UnillEl'Siljt' 


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1Pii;eilf5e c;heck the ,respon.se whic;h best describes your usual a:birrties OVER THE ,PAS,T WEEK:: 
HYGIENE 
Are you able to, 
- Wash .and d,y ~ •-ff body? 
- Te;ke a tub balh? 
- Get on and off lhe 'oile ? 
REACH 
Are you able to, 
- Reach. and g;et down 3 5 pound object 
Wt!hou 
ANY 
Difficully 
With 
SOME 
Diffroutty 
(such as, a ba9 a sugar) from jU!St .abo/\le your head? 
- Bend down to pick up c/o!h.ing from lhe llloor? 
GRIP 
Are you able to,: 
- Open C[lf doors? 
- Open jars. which tisve been pre,,.ioU!Sly ,opened? 
- Tu:m fa.ucets on ancl off? 
ACTIVITIES 
A-re you able toe 
- Run etrands and shop? 
- Get in a:nd OU of a car? 
P,lea<Se esheck any AIDS OR DEVIC 
.Rait5ed tooet seat 
:Bal',htub seat 
__ Jar openE>r (fur jars 
premusly opened} 
__ Lon gi-h:andled appliances for reach 
__ Lon gi-1->andled applrances in ballhroom 
__ other (Specify:---------~ 
Wrth 
M UCH 
Difliculfy 
Pilease eshecl< any cate~ri:es for whicih you usua'lly need HELP FROM .ANOTHER PE:RS0N: 
__ Hygiene 
Reach 
__ Gripping and ,opening things 
Errands and chores 
We-a:r-e also interested in learning w:hethe.-or not you are .affected by pain because of your illness_ 
How much pain have you lla:d because of your illness IN llHE PAST WEEK: 
PU.CEA VE!iUlCM. { I) MARK OtfliiE LINE TO INOICATIE Thie SEVERITY Of THE AIN.. 
NO 
PAIN 
0 
-2. -
SEVERE 
PAI 
100 
'Ul'4ABLE 
To Do 
HYG NEW __ 
_ 
REACHNEW __ 
G:RIPNEW __ _ 
ACTNNEW __ 
_ 
HYGNASST __ 
RCHASST 
ACTVASST __ 
_ 
PAINSCAI. 
l\tJSiamnrd UnillEl'Sity 


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Appendix 10.
FACIT-Fatigue: Functional Assessment of Chronic Illness 
Therapy -Fatigue Scale
FACIT Fatigue Scale (Version 4) 
Below is a list of statements that other people with your illness have said are important. Please select 
one number per line to indicate your response as it applies to the past 7 days. 
H!7 
I feel fatigued ................................................ ..................... . 
Hl12 
I feel weak all over ......................... ............... ...................... 
An\ 
I feel listless ("washed out") ............................ ................... 
An2 
I feel tired ............................................................................ 
An3 
I have trouble starting things because I am tired ............. .... 
An4 
An5 
An7 
I am able to do my usual activities ..... .............. ............... 
An8 
An\2 
An\4 
An\ 5 
I am frustrated 
0 
e things I want 
to do ... .............. 
...... ............ ... ......... .......... 
An\6 
English (Universal) 
Copyright 1987, 1997 
Not 
at all 
0 
0 
0 
0 
0 
0 
0 
0 
A little 
Some-
Quite 
Very 
bit 
what 
a bit 
much 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
2 
3 
4 
16Noveni:ier2007 


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Appendix 11.
SF-36v2: 36-Item Short-Form Health Survey Version 2
Your Health and Well-Being 
This survey asks for your views about your health. This information will help 
keep track of bow you feel and bow well you are able to do your usual activities. 
Thank you for completing this s11rvey! 
For each of the following questions, please mark a 
describes your answer. 
1. In general, would you say you 
· 
Excellent 
Poor 
T 
2. 
ago, bow would you rate your health in general 
!!.fil!.? 
Much better 
Somewhat 
About the 
Somewhat 
Much worse 
now than one 
better 
same as 
worse 
now than one 
year ago 
now than one 
one year ago 
now than one 
year ago 
year ago 
year ago 
T 
T 
T 
T 
T 
SF-36v2"' Healtl1 Survey © 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Incorporated. All rights reserved. 
SF-3114' i a registered trademark of Medical outcome Trust. 
(SF-36v2., Health survey Standard. United States (Engli&i)) 


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3. The following questions are about activities you might do during a typical 
day. Does your health now limit you in these activities? Ifso, how much? 
Yes, 
Yes, 
No, not 
limited 
limited 
limited 
a lot 
a little 
at all 
T 
T 
T 
, Vigorous activities, such as rnnning, lifting 
heavy objects, participating in strenuous sports .................... .. D , ............. D , ............. D , 
s Moderate activities, such as moving a table, pushing 
a vacuum cleaner, bowling, or playing golf.. ......................... . 
, Lifting or carrying groceries........ ... ... ............ ............ ... ..... . ... Cl ............. D , ............. D , 
........... 
........... 
, ............. 
............. 
SF-36v2® Health Survey© 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Incorporated. All rights reserved. 
SF-36® is a registered trademark of Medical outcomes Trust. 
(SF-36v2® Health Survey Standard, United States (English)) 


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4. During the past 4 weeks, how much of the time have you had any of the 
following problems with your work or other regular daily activities!!_! 
result of your physical health? 
, Cut down on the amount of 
time you spent on work or 
All of 
the time ... 
Most of 
the time ... 
Some of 
the time ... 
A little of 
None of 
the time 
the time 
... ... 
other activities .................................. 
1 •••••••••••••• D 2 • •• • •• • •. •• • •• D 
4 ............. D s 
b 
Accomplished less than you 
would like ........................................ 
1 •••• ••• ••• •••• D 2 ••••••• •• 
, Were limited in the kind of 
work or other activities .................... 
1. ••• • •• ••••••• D 2 •••••••••••• • 
, Had difficulty perfom1ing the 
work or other activities (for 
example, it took extra effort) ........... 
1 •••
••••••••• 
5. During the past 4 w 
following p 
r other regular daily activities as a 
result of an 
uch as feeling depressed or anxious)? 
, Cut down on the amount of 
time you spent on work or 
All of 
the time ... 
Most of 
the time ... 
Some of 
the time ... 
A little of 
None of 
the time 
the time 
... ... 
other activities .................................. 
1 •••• • ••••• • •• • D 2 •• • •• • •• • •• • •• D , ........... 
4 ............. D s 
b 
Accomplished less than you 
would like ........................................ 
1 .... . .. . .. . ... D 2 ....... . ...... D , .............. 
4 ............. D s 
, Did work or other activities 
less carefully than usual.. ................. 
1 .... . .. . .. . ... D 2 ....... ..... .. D , ............. ............. D , 
SF-36v2® Health Survey © 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Inmporated. All rights reserved. 
SF-3~ is a registered trademark of Medical outcomes Trust. 
(SF-36v2® Health Survey Standard. United States (English)) 


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6. During the past 4 weeks, to what extent has your physical health or 
emotional problems interfered with your normal social activities with 
family, friends, neighbors, or groups? 
Not at all 
8. 
Slightly 
Moderately 
Quite a bit 
Extremely 
... 
Very mild 
... 
... 
... 
Very severe 
ow much did pain interfere with your normal 
k outside the home and housework)? 
Moderately 
Quite a bit 
Extremely 
... 
SF-36v2® Health Survey © 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Incorporated. All rights reserved. 
SF-36" is a registered trademark of Medical Outcomes Trust. 
(SF-36v2® Health Smvey Standard, United States (English)) 


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9. These questions are about how you feel and how things have been with you 
during the past 4 weeks. For each question, please give the one answer that 
comes closest to the way you have been feeling. How much of the time 
during the past 4 weeks ... 
All of 
the time 
T 
Most of 
the time 
T 
Some of A little of the 
the time 
time 
T 
T 
None of 
the time 
T 
, Did you feel full oflife? .................. 
1. ............. D , .............. 
3 •• • • •••••••••• D 
b Have you been very nervous? .......... 
1. ...••• ••••••• D z........... .. 
, .............. 
, Have you felt so down in the 
dumps that nothing could 
cheer you up? ................................... D 1. ... .......... 
. ............ 
d Have you felt calm and 
peaceful? .......................................... D 1. .. 
, Did you have a lot of energy? ......... . 
r Have you felt downhearted 
and depressed? ..... .......................... . 
10. 
During the past 4 weeks, how much of the time has your physical health or 
emotional problems interfered with your social activities (like visiting with 
friends, relatives, etc.)? 
All of 
the time 
T 
Most of 
the time 
Some of 
the time 
T 
A little of 
the time 
None of 
the time 
T 
SF-36v2® Health Survey © 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Incorporated. All rights reserved. 
SF-36® is a registered trademark of Medical outcomes Trust. 
(SF-36v2® Health Survey Standard, United States (English)) 


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11. 
How TRUE or FALSE is each of the following statements for you? 
, I seem to get sick a little 
Definitely 
true 
T 
Mostly 
true 
T 
Don't 
know 
T 
Mostly 
false 
T 
Definitely 
false 
easier than other people .................. D , ............. , ............. , ............... 
4 .. ... .. .... ... D , 
b I am as healthy as 
anybody I know .............................. D , .............. , ............. 
3 ........ .. ..... D 4 ...... .... .... D , 
, I expect my health to 
get worse ......................................... D , .............. D , ........ .. 
3 ............... 
.. .. .......... 
d 
My health is excellent.. ................... D 1. ... . ....... .. D , ........ . 
..... .............. 
~eting these questions! 
SF-36v2® Health Survey © 1992, 1996, 2000 Medical Outcomes Trust and QualityMetric Incrnporated. All rights reserved. 
SF-36® is a registered trademark of Medical Outcomes Trust. 
(SF-36v2" Health Smvey Standard. United States (English)) 


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Appendix 12.
PsAID-12: 12-item Psoriatic Arthritis Impact of Disease 
Questionnaire
The EUlAR Psoriatic Arthritis Impact of Disease: PsAID12 fOI" cliniical practice 
We want you to indicate how much your psoriatic arlhritis irrpacts your health. 
Please tell us how yoo have been feeling this last week. 
1 . Pain 
Circfe the number that best desailes the p.in you felt due to voor psori.atic ..-tluitis 
clJrilg the last week: 
Nonel o 
1 
1 
2 
3 
4 
5 
6 
7 
8 
2. Fatigue 
Circfe the number that best descri:>es the overall level! of fatigue d11e to your 
psori.atic arthritis 'JOll have experienced clJmg the last week: 
g 
10 
fatig~~I O I 1 I 2 I 3 I 4 I 5 I 6 I 1 I 8 I g I 
10 
J . Skin J)f"Oblems 
Circte the number that best descriles the skin problems i11d11ding itching yoofel:t due 
to your psoriatic artmlis clJri'ng the last week: 
1 Extreme 
I "fatally 
exhausted 
None I o I 1 I 2 I 3 I 4 I 5 I 6 I 1 I s I 9 I 10 I Extreme 
4. W011c andk>r leisure activities 
Circle the number that best descriles the· difficulfihli YPl.l had to participate Uty ii work 
andfor leisuie a.clillities due to yotr psmiatic:.u:lhri:tis dunng the last week: 
Nonel o 
1 
1 
1 
2 
5. Flmdional capacity 
3 I -4 
5 
6 
7 
8 
g 
-10 
1 Extreme 
Circle the number that best desailes-the 'difficulty voo had il'I doingi d.ity physical activities 
due to voor psori.atic arthritis; 
(ing tfie last week: 
6. Discomfort 
Circle the number that best descriles the feeling of discomfort and amoyance wilh 
everyday tasks due to your psooatic arthnlis dlJ"ing the l!ast week: 
Nonel o I 1 I 2 
3 
4 
5 
6 
7 
8 
g 
7. Sleep disturbance 
10 I Extreme 
Circle lhe number that best descriles the sleep diffictJlies (i.e., resting at night) voo felt 
due to voor psori.atic ..-thrms during the last week:: 
For-
office 
use only 
Result 
x3 
[I] 
11 


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ll. Coping 
Considemg your psorialic artllrilis oveiall oow well did you cope (manage, deal, make do) 
with your psorialic. artmlis wmg the last week? 
v~ril O I 1 I 2 I 3 I 4 I 5 I 6 
7 
8 
9 
10 I~ 
9.. Anxiety, fear and uncemnnty 
Circte the 11.nnbeir that best desai:les the level of anxiety, tear aid uncertainly (for exarJl}le 
aboot the tutu~, traalmenls, fear of loneliness) due to you- psorialic arttnitis you have 
experienced during lhe last week: 
None I o I 1 I 2 I 3 I 4 I 5 I 6 I 1 I s I 9 I 10 I Extreme 
1CI. Embarrassment andklr shame 
Considemg your psolialic artlirilis oveiall cirde the number that best describes lhe revel 
of eimarrassment andfor shame due to your appearance expellienced di.ing ttle last week: 
Nonel o 1 1 1 2 1 3 1 4 1 5 1 6 1 1 1 s 1 9 1 10 !Extreme 
11. Social paftiicipation 
Circte the number that best descmes the difficulties you had 
parlici}ate July ii sociall 
activities (i11duding refationships with family andfor poop e efY ose to you) dire to your 
psorialic arthritis dulingi ttle last week: 
Nonel o 1 1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
1 Extreme 
12. Depression 
Circle the number that best descriles the I eve 
deprl:!SSion due to your psooatic arthlilis 
you have experienced during the last,: 
k:· 
Nonel o I 1 I 2 I 3 I 4 I 5 
6 
7 
8 
9 
10 I Extreme 
TIIMK YOU FOR ANSWERING TIIIS QUESilOIRIURE 
For 
CJffice 
use~ 
~l 
x· 
fflil!PsAJDcd 
af20 
Add..,lhe0 
.m divide 
2 


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PsAID12 SCORilNG AHO CALCULATION RUILES 
The PsAID is calculated basoo on 12 Numerical rating scales (NRS) questions. Each NiRS is 
assessed as a number between 0 and 10.. 
Calculation 
Ps.AID finaf val'ue = 
(Ps.AID1 (pain) NRS value (range 0-10) x 3) 
+ (PsAID2 (fatigue) NRS value (range 0-10) x 2), 
+ (PsAID3 (skin) NRS value (range 0-'10) x 2) 
+ (PsAID4 (Work and/or leisure activities) N'RS value (range 0-'10) x 2) 
+ (PsAID5 (fundiOn) NRS value (range 0-10) x 2), 
+ (PsAID6 (discomfort:) !NRS value ( range U-10) .x 2) 
+ (PsAID7 (sleep) NRS value (range 0-10) x2) 
+ (PsAIDB ( coping) NRS value (range 0-10) x 1 ), 
+ (PsAID9 (anxiety) NRS value (range 0-10) x 1) 
+ (PsAID10 {embarrassment), INRS value (range (le. 10) .x 1) 
+ (PsAID111 (social! life) N RS value (range 0-10) x 11) 
+ (PsAID12 {depression) NRSvalue (range 0-10) x 1), 
The tooil is divided by 20. 
MiSS!ing data imputation 
If one of the 12 NRS values co01)o.Sing tfie-RsAID is missing, •the ill1)Ufation is as follows: 
calculate the mean vall!Je of 
11 otffer {non-missilg), NRS (range., 0-10) 
i"l)Ute this value for the , ·ssing NR , 
Then, calculate the PsAJl0 
e~a1 , ed above. 
1f 2 or more of the NRS are missing, the PsAID is oonside{ed as missing value (no imputatioo). 
3 


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CCI


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CCI


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Appendix 17.
PGADA: Patient’s Global Assessment of Disease Activity
Patient's Global Assessment of Disease Activity 
Instructions: 
Considering all the ways psoriatic arthritis affects you, please indicate with a vertical mark 
( I ) through the horizontal line how well you are doing todaY,? 
0 
Very Well 
Note: The VAS scale must be 
100 
Very Poor 


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Appendix 18.
PGAPI: Patient's Global Assessment of Psoriatic Arthritis Pain 
Intensity
Patient's Asse~sment of PsA Paiin Iuteosity 
mstructio1:1~: 
Please mdicate w.ifh. a vertical mark ( I ) through the horizonfca] l!ine the most pain }'Ulll had 
from your psoriaii.c arthritis today. 
0 
opai.n 
100 
U11hearahle p.ain 


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Appendix 19.
CASPAR: Classification Criteria for Psoriatic Arthritis
CASPAR Classification Criteria for Psoriatic Arthritis 
The classification of PsA based on the CASPAR criteria requir 
the presence of established 
inflammatory arthritis (joints, spine, or enthuses) with at le 
3 
ints from the following 
5 features: 
-
Current psoriasis, OR 
A history of psoriasis, OR 
A family history of psoriasis 
-
Nail dystroph 
oints, while all other clinical features are assigned 1 point. 


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Appendix 20.
PASI including BSA: Psoriasis Area and Severity Index including 
Body Surface Area
Psoriasis Area and Severity Index (P ASI), Including Body Surface Area 
(BSA) 
Intensity 
A representative area of psoriasis is selected for each body region (head and neck, upper limbs, 
trunk, lower limbs) The intensity of erythema, induration and scaling of the psoriasis is assessed 
as none (0), mild (1), moderate (2), severe (3) or very severe (4) 
Body surface area 
The percentage area affected by psoriasis is evaluated in the 4 regions of the body. In each 
region, the area is expressed as nil 0(0), >0- <10% (1), 10- <3CWo (2), 30- <50% (3), 
50- <70% (4), 70- <90% (5) or 90 - 100% (6) 


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Appendix 21. 
mNAPSI: Modified Nail Psoriasis Severity Index 
~lodifil'd Nail Psoriasis Severity Index (mNAPSl) 
mNAPSI will be collected only in subjects with psoriatic nail involvement. 'This tool will ask 
you to assess eaoh nail abnonmlity for each of a subject's nails. If you question which grade 
to give, yom answer should be the lowei- of the grades. Three features or gronp:s of features 
(pitting, onycholysis together with. oil-drop dyschromia, and cmnibling) of e.ach fingernail 
will be graded on a scale from zero to 3, according lo the directions below. Four fe.ature:s 
(leukonychia., splinter hemorrhages, hypen..-eratosi.s, and red spots in the lunula) will be graded 
as enher present or ab.sent for each fingemail. 
1. Onycholysis: Separation of the nail plate from the nail bed. The separated part of tche nail is 
opaque and can have white, yellow, or greenish tinge. If tf',.ere is"'a piece of nail missing, 
est.iruate where the nail nomuilly v;rould have ended at t,he eud o the nail bed, and count that 
missing part as involved in onychot:ysis. 
Oil-drop (salmon patch) dyschromia: Reddish-bro\11"':ll 
iscolofittion u.ndtt lihe nail plate. 
Onycholysis and oil-drop dyschrnmia are c-ensiderfd togetl:ier. Whe_n looking at the nail, 
combine the total percentage area of the 
'" iliat is affected by either .and use that combined 
tot.al to score the nail. 
Score: Percent of nail with onyc.h.olysis 01 ci ~drop dyschromia present 
0 
No onycholys.is or oil drop d:yschromia present 
I 
1-10~{. of the nwh.as o.nycholysis or oil-drop dyschrom.ia 
2 
l 1-30%-0f.:the ruu,1 bs onychofysis or oil-drop dyschromia 
3 
>30% <;>fthe nailhas ouycholysis or oil-dcop dyscmomia 
2. Pitting: Small, shaiy!Y. qefined depressions in the nail surface. Pits tu-e discrete 
abnonnalities ('icepick-tike''f If there is nail plate crumbling that is confluent v.rith pits, do 
not score for pits. If the pits are separate from cow:1bling, they may be sc01~d regaroless of 
whether crumbling is present o.r not. 
Score: Number of pits 
0 
0 
1 
1-10 
2 
l l--419 
3 
~ 50 
3. Nail plate c.rnmbling: Crumbling or fragmentation of friable nail plate which may be 
associated with confluent pitting. Crumbling involves alteration of the nail plate swface. 
Horizontal ridging of the nail, "'wave-like" appearance, and horizontal lines are all features of 
ctmnbling. 
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Score: Bercent of nail with crumbling present 
0 
No cnmrbl.w.g 
1 
1- 25% ,ofth-e nail has ·crumbling 
2 
2~50'·%, of the nail has, crnmblling 
3 
> 500>ii of the :nrl has c1l!IW.bhng 
The next 4 abno1mal.i.ties are sc..m;ed o:ally by their presence Of' absenc.e. A sc..m;e of 1 mdicates 
present and a SCO!e of zero .indicates not present 
1 .. Leukooychia: \\l'hi.te spots in the nail pfate due to psoriasis in 
mid matrix .. Lml'ro:llt)'Cfila 
are ju.st color changes. If it appears that th.ere; is ~o:n 
irFegularit.y ro the :nail smi'ac.e, 
·this may be pifting or cfl!lll:lbling; not l.ecloo:nychia .. If a 
1'e 
' hi.a is adjacent to, Ol' 
confluent i.vilh cn1mblmg o:r pits, it .is counted as part .of the 
hhn.g 
pitting and not as a 
separate almomw!ity: 
2. Spliut,er hemorrhages: Small, longi.fudiml · • 
wu hemo:mb.age under the 
fingeinail. 
3. 
!Iii] bed b.ypetl.--e:ratos:is: Thickened ke.ra · 
Somce: Casell! SE et al f22] 


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Appendix 22.
PhGAP: Physician's Global Assessment of Psoriasis 
Physicfau's Global Ac;se,s.sment of Psoriasis 
The physician ~ul gir,;e a soore on the patients: psoriasis d:ise:ase acfrvity; a.coording to the 
following g,-ades: 
Ioduratiao {I) (avernged over aU lesions· l!ISe the Natrona] Psoriasis Fooodation Refereace 
card for mearuremenrt) 
-
0 = ao evidence of plaque elevation 
-
1 = n1~urirna1 _pl.aque efovation, = 0-25 mm 
-
2 = mild plaque elevation, = ·0.5 mm 
-
3 = moderate piaque elevation,= 0.15 nnn 
-
4 = nmked pl'aque elevation, = 1 mm 
-
:5 = ,vernplaqu:e elevation,= 1.2.5 mm or more 
Ei1ihema (E) (averaged over all lesions) 
-
0 = ao -evidence of-erythema, hypetpigmem.a:,tion · . 
-
1 = farint erythema 
-
2 = light red coloration 
-
3 = moderate red colomt.i.on 
-
4 = bright red ootora.tion. 
-
0 = ao -ev.ide 
-
1 = m1i,nimal: occ.asi.eml. fine scale over I.es than 5% of the lesion 
-
2 = mild; fure sc.rle dominates 
-
3 = moderate.; coarse scale predominates 
-
4 = marked~ tbridc nootenacious scale domiaaites 
-
5 = se,;-ere; '!i'el)' f:bi.ck tenacious scale predominates 


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Appendix 23.
SPARCC Enthesitis Index and LEI: Spondyloarthritis Research 
Consortium of Canada Enthesitis Index and Leeds Enthesitis Index
The following will be assessed within the electronic Clinical Outcomes Assessment for 
enthesitis:
0 Supraspinatus inse ie 
S ARCC Only) 
f) Lateral epicondyle humerus (Both SPARCC and LEI) 
8 Medial epicondyle humerus (SPARCC Only) 
C, Greater trochanter (SPARCC Only) 
0 Medicalcondylefemur (LEI Only) 
0 Quadriceps insertion into the superior border of patella (SPARCC Only) 
@ Patellar tendon insertion into the inferior pole of patella OR tibia tuberosity (SPARCC Only) 
(!} Achilles tendon (Both SPARCC and LEI) 
€) Insertion plantarfascia (SPARCC Only) 


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Appendix 24.
SJC66 / TJC68: Swollen and Tender Joint Count
An overview of the (66 I 68) joints to be assessed bilaterally are provided below: 
• Temporomandibular 
• 
Stemoclavicular 
• 
Acromioclavicular 
• 
Shoulder 
• 
Elbow 
• 
Wrist 
• 
Metacarpophalangeal: first, second, third, fourth, fifth 
• 
Proximal interphalangeal: first, second, third, fourth fifth 
• 
Distal interphalangeal: second, third, fourt 
H. I 
• 
lp 
• 
Knee 
• 
Ankle 
• Tarsus 
• 
Proximal interpha 
Replaced / missing ( or otfi FWise not assessable) joints should be documented at Day 1 and 
omitted from further evaluation during the study. 
1 Assessed for tenderness only 


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Appendix 25.
LDI: Leeds Dactylitis Index
• 
mEmedic I s arch ltd 
The Leeds Dactylorneter 
Dactylitis has been defined as" uniform swelling 
such that the soft tissues between the 
metacarpophalangeal and proximal 
inlerphalangeal, proximal and distal 
inlerphalangeal, and/or distal inlerphalangeal Joint 
and digital tuft are diffusely swollen lo the extent 
that the actual Joint swelling could no longer be 
independently recognised."(1) Dactylitis is a 
hallmark clinical feature in patients with 
spondyloarthropathies (SpA) and is commonly 
observed in psoriatic arthritis. 
Dactylitis occurs in 16-48% of cases of psoriatic 
arthritis (PsA). Acute dactylitis has been shown to 
be a clinical indicator ol disease severity in PsA; 
conversely, chronic. non-tender diffuse dactylitic 
swelling may be less clinically significant (2). 
Dactylitis is due to inflammation in the majority of 
tissues in the digit- the tendon sheaths, joints, 
bones and soft-tissues in between (3). Recurrent 
dactylitis, often in the same digit(s), may be the 
only clinical manifestation of PsA. 
The only validated tool for assessing dactylitis is 
the Leeds Dactylometer (4). The validity of this 
instrument has been assessed using the 
OMERACT filter. The instrument and tool J:!ave 
demonstrated good evidence of responsiY~ i'iS 
in a clinical trial (5).1 n addition. the instrument 
incorporates a definition of dactylitisrfa 10% 
difference in the ratio of circumfere nce o tAe 
affected digit to the contralateral digit) . U~mg Ifie 
contralateral digit as a nor la'for enab) 
any 
inter-individual variation in measure.men 
technique to be minimised Jr( inst ument comes 
with an assessment sheet1see revey;e) which 
provides automatic computa On 
tne Leeds 
Dactylitis Index. 
How to use the Leeds Dactylom eter 
The fingers and toes are visually inspected by 
the examiner. Those digits which look 
dactylitic are measured. 
2. 
slip the loop of the Dactylometer around the 
base of the digit adjacent to the web space. 
Pull the indicator stlip tight so that the base of 
the digit blanches slightly (see illustration) 
The collar of the device should be finn ly 
pressed against the base oflhe digit, as 
illustrated. 
3. Record the circumference in mm on the 
Dactylom eter record sheet 
4. 
Repeatthe procedure on the contralateral 
digit 
5. If both ipsilateral and contralateral digits are 
thought to be dactyitic then use the reference 
range (given at the foot of the sheet) as the 
comparator. 
6. 
Only record the digits with a 10% difference in 
circumference 
7. 
Squeeze the digit tefweenthejoints and 
record the tenderness as indicated 
8. 
Calculate the total score as indicated or enter 
the values in the Excel spreadsheet. 
Reference List 
(1) 
Rothschild BM, Pingitore C, Eaton M Dactylitis· 
implications for clinical practice. Seminars in Arthritis & 
Rheumatism I 998; 28( I) :41-47. 
(2) 
Brockbank JE, SteinM, Schentag CT, Gladman DD. 
Th.ctytitis in i:roriatic arthritis: a marker for disease 
reverity? Ann Rheum Dis2005;64(2)188-190. 
(3) 
Healy PJ, Groves C, Chandramohan M, Helliwell PS. 
MRI changes in p;oriatic dactylitis extent of pathology, 
relationship to tenderness and correlation with clinical 
indices. Rheumatology2008; 47(1):92-95. 
(4) 
Helliwell PS, Firth J, lbrahimGH, MelromRD, Shah!, 
Turner DE. Development of an assessment tool for 
dactytiti.sin p:i.tients with p;oriatic arthritis. Journal of 
Rheumatology 32(9): 1745-50, 2005. 
(5) 
HealyPJ, Helliwell PS. Measuring dactylitis in clinical 
trials: which is the best instrument to use? [see commenO. 
Journal ofRheumatology34(6):1302-6, 2007. 
©MI EM edical Research Ltd 


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DACTYLITIS SCORE SHEET 
Address Label 
Please indicate dactyliticjoints 
Finger/ Toe 
TOTAL 
Standard reference· Table - hands 
Di_1.?.it 
Men 
Women 
Thumb 
70 
58 
Index 
63 
54 
Middle 
63 
54 
Rin2 
59 
50 
Little 
52 
44 
Tenderness score: response to squec7..e 
0 no tenderness 
I tender 
2 tender and wince 
3 tender and withdraw 
Doc 164-1 
28'" June 20 10 
© MJE Medical Research Ltd. 
Date: 
Tenderness Score 
Final Score: [{(A/8)-
(C) 
l }xlOO)xC 
Table - feet 
Digit 
Men 
Women 
Great toe 
82 
72 
Second 
52 
46 
Middle 
50 
44 
f ourth 
50 
44 
Little 
52 
45 


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Appendix 26.
PhGADA: Physician’s Global Assessment of Disease Activity
Place a mark on the line below to indicate Ps 
subject's self-assessment): 
No Disease Ac.tivity 
0 
:Maximum Disease Activity 
100 

SAP_001.pdf: 
 
STATISTICAL ANALYSIS PLAN
Study Title:
A Phase 3, Randomized, Double-blind, Placebo and 
Adalimumab-controlled Study to Evaluate the Efficacy and 
Safety of Filgotinib in Subjects with Active Psoriatic Arthritis 
Who Are Naïve to Biologic DMARD Therapy
Name of Test Drug:
Filgotinib
Study Number:
GS-US-431-4566
Protocol Version (Date):
Amendment 2: 17 April 2020
Analysis Type:
Final Analysis 
Analysis Plan Version:
1.0
Analysis Plan Date:
16 July 2021 
Analysis Plan Author(s):
CONFIDENTIAL AND PROPRIETARY INFORMATION
PPD
(rJ GILEAU 


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TABLE OF CONTENTS
TABLE OF CONTENTS................................................................................................................................................2
LIST OF IN-TEXT TABLES .........................................................................................................................................4
LIST OF IN-TEXT FIGURES........................................................................................................................................4
LIST OF ABBREVIATIONS.........................................................................................................................................5
1.
INTRODUCTION..................................................................................................................................................8
1.1.
Study Objectives........................................................................................................................................8
1.2.
Study Design .............................................................................................................................................9
1.3.
Sample Size and Power ...........................................................................................................................11
2.
TYPE OF PLANNED ANALYSIS......................................................................................................................12
2.1.
Final Analysis..........................................................................................................................................12
3.
GENERAL CONSIDERATIONS FOR DATA ANALYSES.............................................................................13
3.1.
Analysis Sets ...........................................................................................................................................13
3.1.1.
All Randomized Analysis Set................................................................................................13
3.1.2.
Full Analysis Set....................................................................................................................13
3.1.3.
Safety Analysis Set................................................................................................................13
3.2.
Subject Grouping.....................................................................................................................................14
3.3.
Strata and Covariates...............................................................................................................................14
3.4.
Multiple Comparisons .............................................................................................................................15
3.5.
Missing Data and Outliers.......................................................................................................................15
3.5.1.
Missing Data..........................................................................................................................15
3.5.2.
Outliers ..................................................................................................................................15
3.6.
Data Handling Conventions and Transformations ..................................................................................15
3.7.
Analysis Visit Windows..........................................................................................................................16
3.7.1.
Definition of Study Day ........................................................................................................16
3.7.2.
Analysis Visit Windows........................................................................................................17
3.7.3.
Selection of Non-Efficacy Data in the Event of Multiple Records in an 
Analysis Visit Window .........................................................................................................21
4.
SUBJECT DISPOSITION ...................................................................................................................................22
4.1.
Subject Enrollment and Disposition........................................................................................................22
4.2.
Extent of Study Drug Exposure and Adherence......................................................................................23
4.2.1.
Duration of Exposure to Study Drug.....................................................................................23
4.2.2.
Adherence to Study Drug ......................................................................................................24
4.3.
Protocol Deviations .................................................................................................................................25
4.4.
Assessment of COVID-19 Impact...........................................................................................................25
4.4.1.
Study Drug or Study Discontinuation Due to COVID-19.....................................................25
4.4.2.
Protocol Deviations Due to COVID-19 ................................................................................25
4.4.3.
Missed and Virtual Visits due to COVID-19 ........................................................................26
4.4.4.
Adverse Events due to COVID-19........................................................................................26
5.
BASELINE CHARACTERISTICS .....................................................................................................................27
5.1.
Demographics and Other Baseline Characteristics .................................................................................27
5.2.
Baseline Disease Characteristics .............................................................................................................27
5.3.
Medical History.......................................................................................................................................30
6.
EFFICACY ANALYSES.....................................................................................................................................31


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6.1.
General Considerations ...........................................................................................................................31
6.2.
Primary Efficacy Endpoint......................................................................................................................32
6.2.1.
Definition of the Primary Efficacy Endpoint ........................................................................32
6.2.2.
Primary Analysis of the Primary Efficacy Endpoint.............................................................35
6.3.
Key Secondary Efficacy Endpoints.........................................................................................................36
6.3.1.
Definition of Key Secondary Efficacy Endpoints.................................................................36
6.3.2.
Analysis Methods for Key Secondary Efficacy Endpoints ...................................................39
6.4.
Other Secondary Efficacy Endpoint........................................................................................................40
6.4.1.
Definition of Other Secondary Endpoints .............................................................................42
6.4.2.
Analysis Methods for Other Secondary Endpoints ...............................................................47
6.5.
Changes From Protocol-Specified Efficacy Analyses ............................................................................48
7.
SAFETY ANALYSES.........................................................................................................................................49
7.1.
Adverse Events and Deaths.....................................................................................................................49
7.1.1.
Adverse Event Dictionary .....................................................................................................49
7.1.2.
Adverse Event Severity .........................................................................................................49
7.1.3.
Relationship of Adverse Events to Study Drug.....................................................................49
7.1.4.
Serious Adverse Events.........................................................................................................49
7.1.5.
Treatment-Emergent Adverse Events....................................................................................49
7.1.6.
Summaries of Adverse Events and Deaths............................................................................50
7.1.7.
Adverse Events of Special Interest........................................................................................52
7.2.
Laboratory Evaluations ...........................................................................................................................53
7.2.1.
Summaries of Numeric Laboratory Results ..........................................................................54
7.2.2.
Graded Laboratory Values ....................................................................................................55
7.2.3.
Liver-related Laboratory Evaluations....................................................................................57
7.2.4.
Complete Blood Count-Related Laboratory Evaluations......................................................57
7.3.
Body Weight and Vital Signs..................................................................................................................58
7.4.
Prior and Concomitant Medications........................................................................................................59
7.4.1.
Prior Medications ..................................................................................................................59
7.4.2.
Concomitant Medications......................................................................................................59
7.5.
Other Safety Measures ............................................................................................................................60
7.6.
Changes From Protocol-Specified Safety and Other Analyses...............................................................60
8.
REFERENCES.....................................................................................................................................................61
9.
SOFTWARE.........................................................................................................................................................62
10.
SAP REVISION...................................................................................................................................................63
11.
APPENDICES......................................................................................................................................................64
Appendix 1.
Heath Assessment Questionnaire Disability Index (HAQ-DI)................................................65
Appendix 2.
FACIT-Fatigue Scale (Version 4) and Scoring Guidelines.....................................................67
Appendix 3.
Oral Corticosteroids Dose Conversion Chart ..........................................................................69
Appendix 4.
Sample SAS Code for Analysis of Binary Endpoints .............................................................70
Appendix 5.
Determining Missing and Virtual visits due to COVID-19.....................................................71
Appendix 6.
Lists of PsA Medications.........................................................................................................72


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LIST OF IN-TEXT TABLES
Table 3-1.
Analysis Visit Windows for Joint Count Assessment, HAQ-DI, PGADA, PGAPI, 
PhGADA, CRP, Vital Signs, Weight, and Safety Laboratory Data (Lipid Data 
Excluded).................................................................................................................................18
Table 3-2.
Analysis Visit Windows for Lipid Data ..................................................................................19
Table 3-3.
Analysis Visit Windows for PhGAP Data...............................................................................19
Table 3-4.
Analysis Visit Windows for PASI including BSA, mNAPSI, SPARCC Enthesitis 
Index and LEI, LDI Data.........................................................................................................20
Table 3-5.
Analysis Visit Windows for FACIT-Fatigue, SF-36v2, PsAID-12 Data................................20
Table 6-1.
Composition of the 28 Joints...................................................................................................34
Table 11-1.
Examples of search terms for “COVID-19” and “Virtual” used to identify missed 
and virtual visits.......................................................................................................................71
LIST OF IN-TEXT FIGURES
Figure 1-1.
Study Design............................................................................................................................11


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LIST OF ABBREVIATIONS
ACR
American College of Rheumatology
ACR20/50/70
American College of Rheumatology 20/50/70% improvement
ADA
adalimumab
AE
adverse event
AESI
adverse events of special interest
ALP
alkaline phosphatase
ALT
alanine aminotransferase
AST
aspartate aminotransferase
ATC
anatomical therapeutic chemical drug class
bioDMARD
biologic disease modifying anti-rheumatic drug
BLQ
below the limit of quantitation
BMI
body mass index
BSA
body surface area
CASPAR
Classification Criteria for Psoriatic Arthritis
CBC
complete blood count
CI
confidence interval
eCRF
electronic case report form
COVID-19
coronavirus (2019 nCOV)
CRP
C-reactive protein
csDMARDs
conventional synthetic disease-modifying anti-rheumatic drugs
CSR
clinical study report
CTCAE
Common Terminology Criteria for Adverse Events
DAPSA
Disease Activity in Psoriatic Arthritis
DAS28
disease activity score for 28 joint count
DMC
data monitoring committee
ECG
electrocardiogram
EDC
electronic data capture
eCRF
electronic case report form
EQ-5D-5L
EuroQoL 5 Dimensions with 5 Levels
ET
early termination
FACIT-Fatigue
Functional Assessment of Chronic Illness Therapy-Fatigue
FAS
full analysis set
GI
gastrointestinal 
GSI
Gilead Sciences
HAQ-DI
Health Assessment Questionnaire-Disability Index
HLGT
high-level group term
HLT
high-level term
CCI-


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HRQoL
health-related quality of life
HCRU
healthcare resource utilization questionnaire
hsCRP
high-sensitivity C-Reactive Protein
ID
identification
IPD
important protocol deviation
IXRS
interactive voice/web response system
LDA
low disease activity
LDI
Leeds Dactylitis Index
LLOQ
lower limit of quantitation
LLT
lower-level term
LOQ
limit of quantitation
LS
least squares
LTE
long-term extension
MACEs
major adverse cardiovascular events
MCS
mental component score
MDA
Minimal Disease Activity
MedDRA
Medical Dictionary for Regulatory Activities
MI
multiple imputation
MMRM
mixed model repeated measures
MNAR
missing not at random
MRI
Magnetic Resonance Imaging
MST
MedDRA search term
MTX
methotrexate
NRI
non-responder imputation
NRS
numerical rating scale
NSAIDs
non-steroidal anti-inflammatory drugs
OC
observed case
PASDAS
Psoriatic Arthritis Disease Activity Score
PASI including BSA
Psoriasis Area and Severity Index including Body Surface Area
PASI75 
Psoriasis Area and Severity Index 75% improvement
PCS
physical component summary
PD
pharmacodynamics 
PGADA
Patient’s Global Assessment of Disease Activity
PGAPI
Patient’s Global Assessment of PsA Pain Intensity
PhGADA
Physician’s Global Assessment of Disease Activity
PhGAP
Physician’s Global Assessment of Psoriasis
PK
pharmacokinetic
PP
per-protocol
PROs
patient reported outcomes
PsA
psoriatic arthritis


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PsAID-12
12-item Psoriatic Arthritis Impact of Disease
PsAMRIS
Psoriatic Arthritis Magnetic Resonance Imaging Score
PsARC
Psoriatic Arthritis Response Criteria
PT
preferred term
PTM
placebo to match
Q1, Q3
first quartile, third quartile
q2w
once every two weeks
q.d.
quaque die (each day)
SAE
serious adverse event
SAP
statistical analysis plan
SBP
systolic blood pressure
SD
standard deviation
SE
standard error
SF-36v2
36-item short form survey version 2
SJC/TJC
Swollen and Tender Joint Count
SMQ
standardized MedDRA query
SOC
system organ class
SPARCC Enthesitis 
Index and LEI
Spondyloarthritis Research Consortium of Canada Enthesitis Index and Leeds Enthesitis 
Index
TDC 
tender dactylitis count
TEAE
treatment-emergent adverse event
TFLs
tables, figures, and listings
ULN
upper limit of normal
VAS
visual analog scale
VLDA 
Very Low Disease Activity
WBC
white blood cell
WHO
World Health Organization
WPAI-PsA
Work Productivity and Activity Impairment for Psoriatic Arthritis


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1.
INTRODUCTION
This statistical analysis plan (SAP) describes the statistical analysis methods and data 
presentations to be used in tables, figures, and listings (TFLs) in the clinical study report (CSR) 
for Study GS-US-431-4566. This SAP is based on the study protocol amendment 2 dated 
17 April 2020 and the electronic case report form (eCRF). The SAP will be finalized before 
database finalization. Any changes made after the finalization of the SAP will be documented in 
the CSR.
1.1.
Study Objectives
The primary objective of this study is as follows:

To evaluate the effect of filgotinib compared to placebo in active PsA as assessed by the 
American College of Rheumatology 20% improvement (ACR20) response at Week 12
The secondary objectives of this study are as follows:

To evaluate the effect of filgotinib on core domains of psoriatic arthritis (PsA, e.g. peripheral 
arthritis, psoriatic skin disease, enthesitis and dactylitis) as assessed by Minimal Disease 
Activity (MDA), Very Low Disease Activity (VLDA), ACR responses, Psoriasis Area and 
Severity Index including Body Surface Area (PASI including BSA) responses, 
Spondyloarthritis Research Consortium of Canada Enthesitis Index and Leeds Enthesitis 
Index (SPARCC Enthesitis Index and LEI), Leeds Dactylitis Index (LDI), Psoriatic Arthritis 
Disease Activity Score (PASDAS), Disease Activity Index for Psoriatic Arthritis (DAPSA), 
Modified Nail Psoriasis Area and Severity Index (mNAPSI), and Physician’s Global 
Assessment of Psoriasis (PhGAP) 

To evaluate the effect of filgotinib on physical function in active PsA as assessed by Health 
Assessment Questionnaire-Disability Index (HAQ-DI)

To evaluate the effect of filgotinib on fatigue and quality of life in active PsA as assessed by 
Functional Assessment of Chronic Illness Therapy - Fatigue Scale (FACIT-Fatigue), 36-item 
Short-Form Health Survey Version 2 (SF-36v2), and 12-item Psoriatic Arthritis Impact of 
Disease (PsAID-12)

To evaluate the efficacy of filgotinib versus adalimumab in active PsA as assessed by 
ACR20 response

To evaluate the safety and tolerability of filgotinib


Filgotinib 
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Statistical Analysis Plan - Final Analysis 
I 
I 
I 
I 
I 
1.2. 
Study Design 
Version 1.0 
This is a randomized, double-blind, active-contrnlled, Phase 3 study in adult male and female 
subjects with active PsA who have had an inadequate response or intolerance to 1 or more 
therapies for PsA, such as conventional synthetic disease-modifying anti-rheumatic drngs 
(csDMARDs), apremilast and I or non-steroidal anti-inflammato1y diugs (NSAIDs), but have 
never received a biologic DMARD (bioDMARD) for PsA or psoriasis. 
The study consists of two paiis, the Main Study: Screening through Week 16 (inclusive), and the 
Long Te1m Extension (LTE): after Week 16 up to approximately 2.25 yeai·s. 
Part 1-Main Study (Screening through Week 16): 
Approximately 854 subjects will be randomized in a 2:2: 1 :2 ratio to one of 4 dosing groups as 
outlined below. 
Randomization will be stratified by geographic region, concmTent use of conventional synthetic 
DMARD(s) (csDMARDs) and / or apremilast at randomization (yes or no) 
Dosing groups in the Main Study: 
• 
Filgotinib 200 mg group: filgotinib 200 mg once daily+ placebo to match (PTM) filgotinib 
100 mg once daily+ PTM adalimumab subcutaneous (SC) injection once eve1y two weeks 
(q2w) 
• 
Filgotinib 100 mg group: PTM filgotinib 200 mg once daily+ ftlgotinib 100 mg once daily 
+ PTM adalimumab SC injection q2w 
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
Active comparator group: PTM filgotinib 200 mg once daily + PTM filgotinib 100 mg once 
daily + adalimumab 40 mg SC injection q2w

Placebo control group: PTM filgotinib 200 mg once daily + PTM filgotinib 100 mg once 
daily + PTM adalimumab SC injection q2w
NOTE: All subjects will discontinue adalimumab / PTM injections by the Week 16 Visit (the last 
injections should be at approximately Week 14).
Part 2 – LTE (After the Week 16 Visit for 2 years):
After completion of the Main Study, subjects who have not permanently discontinued study drug 
will continue on to the LTE as follows:

Those who were assigned to the filgotinib groups will continue on the same study drug 
assignments

Those who were assigned to the placebo or active comparator group will be reassigned 1:1 in 
a blinded fashion to filgotinib 200 mg or 100 mg once daily
Dosing groups in the LTE:

Filgotinib 200 mg group: filgotinib 200 mg once daily + PTM filgotinib 100 mg once daily

Filgotinib 100 mg group: PTM filgotinib 200 mg once daily + filgotinib 100 mg once daily
For the first 16 weeks of study participation, subjects who temporarily interrupt or permanently 
discontinue study drug for any reason are to continue with study visits and assessments through 
the Week 16 Visit, per protocol Section 3.5 unless the subject withdraws consent, is lost to 
follow-up, and / or continued participation in the study is medically contraindicated, per 
investigator’s judgment. Study drug interruption and discontinuation considerations are outlined 
in protocol Section 3.5. All subjects who permanently discontinue study drug should continue to 
receive standard of care treatment for their PsA including additional therapies, if required.


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Figure 1-1.
Study Design
1.3.
Sample Size and Power
Sample size is determined based on the non-inferiority test of each filgotinib group compared to 
the adalimumab group on the ACR20 response rate at Week 12. When assuming the ACR20 
response rate being 52% and 60% for the adalimumab and each filgotinib group, and 38.6% for 
the placebo group, 244 subjects in each filgotinib group and placebo group, and 122 subjects in 
the adalimumab group are required to obtain 90% power at a two-sided 0.025 significance level 
to demonstrate that filgotinib group preserves more than 50% of the effect of adalimumab with 
respect to the ACR20 response rate at Week 12. 
A sample size of 244 subjects in each filgotinib group and the placebo group will provide over 
95% power to detect a difference in ACR20 response rate of 21.4% at Week 12 (38.6% and 
60% for the placebo group and each filgotinib group, respectively) using a two-sided 
0.025 significance level superiority test.
In summary, the total sample size will be approximately 854 subjects per original planning.
The study was terminated per Sponsor’s decision after 67 subjects had been enrolled. At study 
termination, 13 out of 67 subjects continued on to the LTE, and 7 of those 13 subjects were 
terminated immediately after entering LTE phase. All the other subjects were prematurely 
discontinued from or completed the Main Study visits.
Part 1: Main Study 
Part 2: Long Tenn Extension 
Screening 
(!:28 days) 
Day 1 
Randomization 
(2:2:1:2) 
Placebo (n=244) 
Week 16 
~2.25 years 
FIL 100 mg 
' 1 ~1-F,-L-200
_ m_g---------------
' 
FIL 100 mg 
Re-Randomization 
(1:1) 


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2.
TYPE OF PLANNED ANALYSIS
2.1.
Final Analysis
After study early termination, the final analysis will be performed for all enrolled subjects. Final 
analysis will occur after outstanding data queries have been resolved or adjudicated as 
unresolvable, and the data have been cleaned and finalized.


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3.
GENERAL CONSIDERATIONS FOR DATA ANALYSES
Analysis results will be presented using descriptive statistics. For categorical variables, the 
number and percentage of subjects in each category will be presented; for continuous variables, 
the number of subjects (n), mean, standard deviation (SD) or standard error (SE), median, first 
quartile (Q1), third quartile (Q3), minimum, and maximum will be presented.
By-subject listings will be presented for all subjects in the All Randomized Analysis Set and 
sorted by subject identification (ID) number, visit date, and time (if applicable). Data collected 
on log forms, such as AEs, will be presented in chronological order within the subject. The 
treatment group to which subjects were randomized will be used in the listings. Age, sex at birth, 
race, and ethnicity will be included in the listings, as space permits.
Given the small number of subjects who entered LTE phase, for all the efficacy and safety 
analyses, unless specified otherwise, all the analyses and summary tables will be generated based 
on the data during Main Study phase (for subjects enrolled under Protocol Amendment (PA) 1 
who stayed in Main Study beyond Week 16 visit, only the data up to Week 16 visit will be 
included). All the data will be presented in the listing.
3.1.
Analysis Sets
Analysis sets define the subjects to be included in an analysis. Analysis sets and their definitions 
are provided in this section. The analysis set will be identified and included as a subtitle of each 
table, figure, and listing.
For each analysis set, the number and percentage of subjects eligible for inclusion, will be 
summarized by treatment group.
A listing of reasons for exclusion from analysis sets will be provided by subject.
3.1.1.
All Randomized Analysis Set
All Randomized Analysis Set includes all subjects who were randomized in the study. This is the 
primary analysis set for by-subject listings.
3.1.2.
Full Analysis Set
The Full Analysis Set (FAS) includes all randomized subjects who took at least 1 dose of study 
drug. The study drugs in this study are filgotinib 200 mg, filgotinib 100 mg, adalimumab and 
PTMs. This is the primary analysis set for efficacy analyses.
3.1.3.
Safety Analysis Set
The Safety Analysis Set includes all subjects who took at least 1 dose of study drug. This is the 
primary analysis set for safety analyses.


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3.2.
Subject Grouping
For analyses based on the All Randomized Analysis Set and FAS, subjects will be grouped 
according to the treatment to which they were randomized. For analyses based on the Safety 
Analysis Set, subjects will be grouped according to the actual treatment received. The actual 
treatment received will differ from the randomized treatment only when their actual treatment 
differs from randomized treatment for the entire treatment duration of each treatment phase.
The treatment groups during the Main Study phase are:

Filgotinib 200 mg once daily

Filgotinib 100 mg once daily

Adalimumab q2w

Placebo 
The treatment groups during the LTE phase are:

Filgotinib 200 mg once daily

Filgotinib 100 mg once daily

Adalimumab switch to filgotinib 200 mg once daily

Adalimumab switch to filgotinib 100 mg once daily

Placebo switch to filgotinib 200 mg once daily

Placebo switch to filgotinib 100 mg once daily
3.3.
Strata and Covariates
Subjects will be randomly assigned to treatment groups via the interactive voice or web response 
system (IXRS) in a 2:2:1:2 ratio to filgotinib 200 mg, filgotinib 100 mg, adalimumab or placebo 
control using a stratified randomization schedule. Stratification will be based on the following 
variables:

Geographic region (Group A includes the following countries: Australia, Canada, New 
Zealand, Spain, and United States; Group B includes the following countries: Bulgaria, 
Poland, Group E includes Japan)

Concurrent use of conventional synthetic DMARD(s) (csDMARDs) and / or apremilast at 
randomization (Yes or No)
List of csDMARD and/or apremilast is provided in Appendix 6.


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If there are discrepancies in stratification factor values between the IXRS and the clinical 
database, the values recorded in the clinical database will be used for analyses. 
For efficacy endpoints, stratification factors and the baseline value of the efficacy variable(s) will 
be included as a covariate in the efficacy analysis model, as specified in Section 6. Given the 
small number of subjects in geographic region Group E, Group B and E will be combined as a 
single group in all the efficacy modeling. 
3.4.
Multiple Comparisons
Due to study early termination and insufficient number of subjects enrolled, the hypothesis 
testings performed and correspondingly reported p-values for all the comparisons planned in this 
SAP will be nominal, and need to be interpreted with caution.
3.5.
Missing Data and Outliers
3.5.1.
Missing Data
In general, missing data will not be imputed unless methods for handling missing data are 
specified. Exceptions are presented in this document.
For missing last dosing date of study drug, imputation rules are described in Section 4.2.1. For 
partial date of initial PsA diagnosis, imputation rules are described in Section 5.2. The handling 
of missing or incomplete dates for AE onset is described in Section 7.1.5.2, and for prior and 
concomitant medications in Section 7.4. Imputation rules adopted in the efficacy analyses are 
specified in Section 6.
3.5.2.
Outliers
Outliers will be identified during the data management and data analysis process, but no 
sensitivity analyses will be conducted. All data will be included in the data analysis.
3.6.
Data Handling Conventions and Transformations
The following conventions will be used for the imputation of date of birth:

Since only the year of birth is collected in the study, “01 July” will be imputed as the day and 
month of birth

If year of birth is missing, then date of birth will not be imputed.
In general, age collected at Day 1 (in years) will be used for analyses and presented in listings. If 
age at Day 1 is not available for a subject, then age derived based on date of birth and the Day 1 
visit date will be used instead. If an enrolled subject was not dosed with any study drug, the 
randomization date will be used instead of the Day 1 visit date. For screen failures, the date the 
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Non-PK data that are continuous in nature but are less than the lower limit of quantitation (LOQ) 
or above the upper LOQ will be imputed as follows:

A value that is 1 unit less than the LOQ will be used to calculate descriptive statistics if the 
datum is reported in the form of “ x” (where x is considered the LOQ). For example, if the 
values are reported as < 50 and < 5.0, values of 49 and 4.9, respectively, will be used to 
calculate summary statistics. An exception to this rule is any value reported as < 1 or < 0.1, 
etc. For values reported as < 1 or < 0.1, a value of 0.9 or 0.09, respectively, will be used to 
calculate summary statistics.

A value that is 1 unit above the LOQ will be used to calculate descriptive statistics if the 
datum is reported in the form of “> x” (where x is considered the LOQ). Values with decimal 
points will follow the same logic as above.

The LOQ will be used to calculate descriptive statistics if the datum is reported in the form of 
“≤ x” or “≥ x” (where x is considered the LOQ).
3.7.
Analysis Visit Windows
3.7.1.
Definition of Study Day
The study consists of two study phases: Main Study phase and LTE phase. Main study is from 
screening through Week16 Visit. The subjects who complete the Main Study and have not 
prematurely discontinued study drug will continue on to the LTE. For the subjects who continue 
on to LTE phase, Main Study phase is up to Week 16 visit date (inclusive); LTE phase is from 
Week 16 visit date + 1 forward (for subjects enrolled under PA 1 who stayed in Main Study 
beyond Week 16 Visit, refer to Section 3.7.2 for exception).
The first dose date of individual study drug will be calculated separately for each study drug 
(ie, filgotinib 200mg, filgotinib 100mg, adalimumab and PTMs) in a treatment group. Study 
Day 1 is defined as the first dose date of any study drug, which is the minimum of the first dose 
dates of individual study drugs in a treatment group.
The last dose date of individual study drug will be calculated separately for each study drug in a 
treatment group. The last dose date for an individual study drug will be the maximum end date 
on study drug administration CRF for the record where the “study drug was permanently 
withdrawn” flag is “Yes”. The last dose date of any study drug will be defined as the maximum 
of the last dose dates of individual study drugs in a treatment group.
Study day will be calculated from the Study Day 1 and derived as follows:

For postdose study days: Assessment Date – Study Day 1 + 1

For days prior to the first dose: Assessment Date – Study Day 1


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For subjects who continue on to the LTE, the LTE Study Day 1 is defined as the first dose date 
of any study drug for LTE. The LTE Study Day will be calculated from the LTE Study Day 1 
and derived as follows:

For days post LTE Study Day 1: Assessment Date – LTE Study Day 1 + 1

For days prior to the LTE Study Day 1: Assessment Date – LTE Study Day 1
3.7.2.
Analysis Visit Windows
Subject visits might not occur on protocol-specified days. Therefore, for the purpose of analysis, 
observations will be assigned to analysis windows.
In general, the study baseline value will be the last nonmissing value on or prior to the first dose 
date of study drug.
For subjects who were re-randomized to LTE phase (placebo or adalimumab treated subjects), 
the re-randomized baseline will be the last nonmissing value obtained on or prior to the first dose 
date of any study drug for LTE.
For subjects enrolled under PA 1 who stayed in Main Study beyond Week 16 Visit, the analysis 
visit window will only be applied to the data up to Week 16 visit.
The analysis windows for joint count assessment, HAQ-DI including subject’s pain assessment, 
Patient’s Global Assessment of Disease Activity (PGADA), Patient’s Global Assessment of 
Psoriatic Arthritis Pain Intensity (PGAPI), Physician’s Global Assessment of Disease Activity 
(PhGADA), CRP, vital signs, weight, and safety laboratory data (lipid data excluded) are 
provided in Table 3-1.


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Table 3-1.
Analysis Visit Windows for Joint Count Assessment, HAQ-DI, 
PGADA, PGAPI, PhGADA, CRP, Vital Signs, Weight, and Safety 
Laboratory Data (Lipid Data Excluded)
Visit Window Study Day
Analysis Visit
Nominal Study Day
Lower Limit
Upper Limit
Baseline
1
(none)
1
Week 2
15
2
22
Week 4
29
23
43
Week 8
57
44
71
Week 12
85
72
99
Week 16
113
100
Week 16 Visit Date – Study 
Day 1 + 1*
Analysis Visit
Nominal LTE Study Day
LTE Lower Limit
LTE Upper Limit
Week 18
15
2
22
Week 20
29
23
43
Week 24
57
44
71
Week 28
85
72
113
Week 36
141
114
183
Week 48
225
184
267
Week 60
309
268
351
Week 72
393
352
435
Week 84
477
436
519
Week 96
561
520
603
Week 108
645
604
687
Week 120
729
688
≥ 729
* For subjects who did not enter LTE phase, upper limit is “>= 113”; for subjects enrolled under PA1 who stayed in Main Study 
beyond Week 16, upper limit is 127.
The analysis windows for lipid data are provided in Table 3-2:


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Table 3-2.
Analysis Visit Windows for Lipid Data
Visit Window Study Day
Analysis Visit
Nominal Study Day
Lower Limit
Upper Limit
Baseline
1
(none)
1
Week 16
113
2
Week 16 Visit Date – Study 
Day 1 + 1*
Analysis Visit
Nominal LTE Study Day
LTE Lower Limit
LTE Upper Limit
Week 48
225
2
393
Week 96
561
394
645
Week 120
729
646
≥ 729
* For subjects who did not enter LTE phase, upper limit is “>= 113”; for subjects enrolled under PA1 who stayed in Main Study 
beyond Week 16, upper limit is 141.
The analysis windows for PhGAP data are provided in Table 3-3.
Table 3-3.
Analysis Visit Windows for PhGAP Data
Visit Window Study Day
Analysis Visit
Nominal  Study Day
Lower Limit
Upper Limit
Baseline
1
(none)
1
Week 2
15
2
22
Week 4
29
23
43
Week 8
57
44
71
Week 12
85
72
99
Week 16
113
100
Week 16 Visit Date– Study 
Day 1 + 1*
Analysis Visit
Nominal LTE Study Day
LTE Lower Limit
LTE Upper Limit
Week 18
15
2
22
Week 20
29
23
43
Week 24
57
44
71
Week 28
85
72
113
Week 36
141
114
183
Week 48
225
184
309
Week 72
393
310
477
Week 96
561
478
645
Week 120
729
646
≥ 729
* For subjects who did not enter LTE phase, upper limit is “>= 113”; for subjects enrolled under PA1 who stayed in Main Study 
beyond Week 16, upper limit is 127.


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The analysis windows for PASI including BSA, mNAPSI, SPARCC Enthesitis Index and LEI, 
LDI data are provided in Table 3-4:
Table 3-4.
Analysis Visit Windows for PASI including BSA, mNAPSI, SPARCC 
Enthesitis Index and LEI, LDI Data
Visit Window Study Day
Analysis Visit
Nominal Study Day
Lower Limit
Upper Limit
Baseline
1
(none)
1
Week 4
29
2
43
Week 8
57
44
71
Week 12
85
72
99
Week 16
113
100
Week 16 Visit Date – Study 
Day 1 + 1*
Analysis Visit
Nominal LTE Study Day
LTE Lower Limit
LTE Upper Limit
Week 20
29
2
43
Week 24
57
44
71
Week 28
85
72
113
Week 36
141
114
183
Week 48
225
184
309
Week 72
393
310
477
Week 96
561
478
645
Week 120
729
646
≥ 729
* For subjects who did not enter LTE phase, upper limit is “>= 113”; for subjects enrolled under PA1 who stayed in Main Study 
beyond Week 16, upper limit is 127.
The analysis windows for FACIT-Fatigue, SF-36v2, PsAID-12 data are provided in Table 3-5
Table 3-5.
Analysis Visit Windows for FACIT-Fatigue, SF-36v2, PsAID-12 Data
Visit Window Study Day
Analysis Visit
Nominal Study Day
Lower Limit
Upper Limit
Baseline
1
(none)
1
Week 4
29
2
71
Week 16
113
72
Week 16 Visit Date – Study 
Day 1 + 1*
Analysis Visit
Nominal LTE Study Day
LTE Lower Limit
LTE Upper Limit
Week 48
225
2
393
Week 96
561
394
645
Week 120
729
646
≥ 729
* For subjects who did not enter LTE phase, upper limit is “>= 113”; for subjects enrolled under PA1 who stayed in Main Study 
beyond Week 16, upper limit is 141.


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Treatment Policy estimand is defined for efficacy analyses, and for efficacy measurements, the 
analysis visit windows will be applied to all available data observed on study.
While on Treatment estimand is defined for safety analysis, and for vital signs, weight, and 
laboratory data, the analysis visit windows will be applied to data collected during the 
on-treatment period. The on-treatment period is defined up to the last dose date of any study 
drug + 7 days.
The safety data collected in the post-treatment safety follow up period will also be summarized. 
The analysis window for the post-treatment follow-up period is defined as from (the last dose 
date of any study drug + 8 days) to (the last dose date of any study drug + 30 days). Data 
obtained after last dose date plus 30 days will be excluded from the summaries, but will still be 
included in the listing.
3.7.3.
Selection of Non-Efficacy Data in the Event of Multiple Records in an 
Analysis Visit Window
Depending on the statistical analysis method, single values may be required for each analysis 
window. For example, change from baseline by visit usually requires a single value, whereas a 
time-to-event analysis would not require 1 value per analysis window.
If multiple valid, nonmissing measurements exist in an analysis window, records will be chosen 
based on the following rules if a single value is needed:

For baseline, the last nonmissing value on or prior to the first dosing date of study drug will 
be selected, unless specified differently. If there are multiple records with the same time or 
no time recorded on the same day, the baseline value will be the average of the 
measurements for continuous data, or the measurement with the lowest severity (e.g., normal 
will be selected over abnormal) for categorical data.

For postbaseline values:
The record closest to the nominal day for that visit will be selected.
If there are 2 records that are equidistant from the nominal day, the later record will be 
selected.
If there is more than 1 record on the selected day, the average will be taken for 
continuous data and the worse severity will be taken for categorical data, unless 
otherwise specified.


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4.
SUBJECT DISPOSITION
4.1.
Subject Enrollment and Disposition
A summary of subject enrollment will be provided by treatment group and overall for each 
country within each geographic region and investigator within a country. The summary will 
present the number and percentage of subjects enrolled. For each column, the denominator for 
the percentage calculation will be the total number of subjects analyzed for that column.
A similar enrollment table will be provided by randomization stratum. The denominator for the 
percentage of subjects in the stratum will be the total number of enrolled subjects. If there are 
discrepancies in the value used for stratification assignment between the IXRS and the clinical 
database, the value collected in the clinical database will be used for the summary. A listing of 
subjects with discrepancies in the value used for stratification assignment between the IXRS and 
the clinical database at the time of data finalization will be provided.
The randomization schedule used for the study will be provided as an appendix to the CSR.
A summary of subject disposition will be provided by treatment group and study phase 
(Main Study and LTE). This summary will present the number of subjects screened, the number 
of subjects who met all eligibility criteria but were not randomized with reasons subjects not 
randomized, the number of subjects randomized, and the number of subjects in each of the 
categories listed below:

Safety Analysis Set 

Full Analysis Set

Completed study drug (Main Study phase)

Did not complete study drug with reasons for premature discontinuation of study drug 
(Main Study phase)

Entered LTE phase

Did not complete study drug with reasons for premature discontinuation of study drug 
(LTE phase)

Did not complete the study with reasons for premature discontinuation of study in Main 
Study and LTE phase respectively
For the status of study drug and study completion and reasons for premature discontinuation, the 
number and percentage of subjects in each category will be provided. The denominator for the 
percentage calculation will be the total number of subjects in the Safety Analysis Set 
corresponding to that column.


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The following by-subject listings will be provided by subject ID number in ascending order to 
support the above summary tables:

Reasons for premature study drug or study discontinuation 

Reasons for screen failure (will be provided by screening ID number in ascending order)

Lot number and kit ID of assigned study drugs
4.2.
Extent of Study Drug Exposure and Adherence
Extent of exposure to study drug will be examined by assessing the total duration of exposure to 
study drug for Main Study and the level of adherence relative to the study drug for Main Study 
specified in the protocol.
4.2.1.
Duration of Exposure to Study Drug
Total duration of exposure to any study drug for Main Study will be defined as last dosing date 
of any study drug for Main Study minus first dosing date of any study drug plus 1, regardless of 
any temporary interruptions in study drug administration, and will be expressed in weeks using 
up to 1 decimal place (e.g., 4.5 weeks).
For subjects with a partial last dosing date (ie, month and year of last dose are known), the latest 
of the dispensing dates of study drug bottles, study drug start dates and end dates, and the 
imputed last dose date (day imputed as 15) will be used as the final imputed last dose date. If the 
subject died and the death date is complete (i.e., not partial date) and before the imputed last dose 
date, the complete death date will be used as the imputed last dose date.
If only year is recorded (ie, month and day of last dose are missing), the latest of the dispensing 
month of study drug bottles, study drug start month, and study drug end month will be used to 
impute the unknown last dose month. If the subject died and the death date has month and year 
available and before the imputed last dose month, then the month of death will be used instead. 
With the month imputed, the aforementioned method will be used to impute the last dose date. 
The total duration of exposure to any study drug for Main Study will be summarized using 
descriptive statistics and using the number (i.e., cumulative counts) and percentage of subjects 
exposed through the following time periods: Baseline (Day 1), Week 2 (Day 15), Week 4 
(Day 29), Week 8 (Day 57), Week 12 (Day 85), Week 16 (Day 113). Summaries will be 
provided by treatment group for the Safety Analysis Set.
No formal statistical testing is planned.


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4.2.2.
Adherence to Study Drug
Adherence will be calculated separately for individual study drugs, including filgotinib 
200 mg)/PTM (tablets), filgotinib 100 mg/PTM (tablets), and adalimumab/PTM (syringes).
The total number of tablets or syringe administered will be summarized using descriptive 
statistics. 
The presumed total number of tablets or syringes administered to a subject will be determined by 
the data collected on the drug accountability CRF using the following formula:
Total Number of Tablets Administered =
No. of Tablets Dispensed ―
No. of Tablets Returned
Total Number of Syringes Administered =
No. of Syringes Dispensed ―
No. of Syringes Returned
If a bottle or a packaging kit is dispensed and the bottle or packaging kit is returned empty, then 
the number of tablets/syringes returned will be entered as zero. If a bottle or a packaging kit is 
dispensed but not returned (missing), then the number of tablets/syringes administered will be 
counted as zero.
On-Treatment Adherence will be calculated to assess the level of adherence to study drugs.
The level of on-treatment adherence to the study drug will be determined by the total amount of 
study drug administered relative to the total amount of study drug expected to be administered 
during a subject’s actual on-treatment period based on the study drug regimen.
The level of on-treatment adherence will be expressed as a percentage using the following 
formula:
Total Amount of Study Drug Administered
On-Treatment Adherence (%) = 
 x 100
Study Drug Expected to be Administered on Treatment






Study drug expected to be administered for filgotinib 200 mg/PTM (tablets) = 1× total duration 
of exposure to any study drug for Main Study (days).
Study drug expected to be administered for filgotinib 100 mg/PTM (tablets) = 1× total duration 
of exposure to any study drug for Main Study (days).
) 
) 


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Study drug expected to be administered for adalimumab/PTM (syringes) = 1×ceil[(min(Last dose 
date of any study drug for Main Study, First dose date of any study drug + 14×7) – First dose 
date of any study drug + 1) /14]. 
Descriptive statistics for the level of on-treatment adherence with the number and percentage of 
subjects belonging to adherence categories (e.g., {< 80%, ≥ 80 to < 90%, ≥ 90%}) will be 
provided by treatment group for the Safety Analysis Set. 
No formal statistical testing is planned.
A by-subject listing of study drug administration and drug accountability will be provided 
separately by subject ID number (in ascending order) and visit (in chronological order).
4.3.
Protocol Deviations 
Subjects who did not meet the eligibility criteria for study entry but randomized in the study, will 
be summarized regardless of whether they were exempted by the sponsor or not. The summary 
will present the number and percentage of subjects who did not meet at least 1 eligibility 
criterion and the number of subjects who did not meet specific criteria by treatment group based 
on the All Randomized Analysis Set. A by-subject listing will be provided for those subjects who 
did not meet at least 1 eligibility (inclusion or exclusion) criterion. The listing will present the 
eligibility criterion (or criteria if more than 1 deviation) that subjects did not meet and related 
comments, if collected. 
Protocol deviations occurring after subjects entered the study are documented during routine 
monitoring. The number and percentage of subjects with important protocol deviations (IPDs) by 
deviation reason (as specified in the IPD plan) will be summarized by treatment group for the All 
Randomized Analysis Set. A by-subject listing will be provided for those subjects with IPD. 
4.4.
Assessment of COVID-19 Impact 
This study was ongoing during the novel coronavirus (2019 nCOV [COVID-19]) pandemic 
which has caused a disruption in the regular visit schedules for this study. Some subjects were 
unable to attend onsite visits due to shelter in place guidelines, site closures, or other reasons. 
This section provides how special situations due to COVID-19 will be handled in the analysis.
4.4.1.
Study Drug or Study Discontinuation Due to COVID-19
A by-subject listing of reasons for premature study drug or study discontinuation due to 
COVID-19 will be created.
4.4.2.
Protocol Deviations Due to COVID-19
A by-subject listing of important protocol deviation related to COVID-19 and non-important 
protocol deviation related to COVID-19 will be provided.


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4.4.3.
Missed and Virtual Visits due to COVID-19
A by-subject listing of subjects with missed or virtual visits due to COVID-19 will be provided 
by subject ID number in ascending order.
Information regarding missed or virtual visits due to COVID-19 was collected as free text in the 
CRF comment fields. The determination of missing or virtual visits due to COVID-19 will be 
done using Natural Language Processing (NLP) to search the CRF comment fields.  A detailed 
explanation of the algorithm is given in Appendix 5.
4.4.4.
Adverse Events due to COVID-19
AEs due to COVID-19 will be included in analyses of AE if applicable, which will be 
determined through COVID-19 standardized MedDRA queries (SMQ) broad search. A 
by-subject listing of AEs due to COVID-19 will be provided.


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5.
BASELINE CHARACTERISTICS
5.1.
Demographics and Other Baseline Characteristics
Subject demographic variables and baseline characteristics will be summarized by treatment 
group and overall using descriptive statistics for continuous variables and using number and 
percentage of subjects for categorical variables. The summary of demographic and other baseline 
characteristics data will be provided for the Safety Analysis Set for the following:

Age (on the first dose date of any study drug)

Age group (< 65 years, ≥ 65 years)

Sex at birth (male, female)

Race

Ethnicity (Hispanic or Latino, not Hispanic or Latino)

Geographic region and country

Weight (kg)

Height (cm)

Body mass index (BMI; in kg/m2)

Smoking Status (non-smoker, former smoker or current smoker)
A by-subject demographic and other baseline characteristics listing, including the informed 
consent date, will be provided by subject ID number in ascending order.
5.2.
Baseline Disease Characteristics
Baseline disease characteristics include:

Concurrent use of csDMARD and/or apremilast at randomization (Yes or No) and daily or 
weekly dose taken at randomization by medication
Only csDMARD and/or apremilast medication records with a start date prior to 
randomization date and an end date on or after randomization date or missing will be 
used for counting the number of subjects with csDMARD and/or apremilast use at 
randomization.
Only csDMARD and/or apremilast medication records with a start date prior to 
randomization date and an end date on or after randomization date or missing that have a 
valid dose, dose unit, and dosing frequency will be used for summarizing daily or weekly 
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
Oral Corticosteroids use on Study Day 1 (Yes or No) and daily dose taken on Study Day 1
Only oral Corticosteroid medication records with a start date prior to Study Day 1 and an 
end date on or after Study Day 1 or missing will be used for counting the number of 
subjects with oral Corticosteroid use on Study Day 1.
Only oral Corticosteroid medication records with a start date prior to Study Day 1 and an 
end date on or after Study Day 1 or missing that have a valid dose, dose unit, and dosing 
frequency will be used for summarizing daily dose taken on Study Day 1. 
All oral Corticosteroid medications’ doses will be converted to prednisone equivalent 
dose (conversion chart is in Appendix 3).
If multiple oral Corticosteroid medications are taken on Study Day 1, the total daily dose 
will be the sum of those medications’ doses at Study Day 1 after conversion.

Topical Corticosteroids use on Study Day 1 (Yes or No)
Only topical Corticosteroid medication records with a start date prior to Study Day 1 and 
an end date on or after Study Day 1 or missing will be used for counting the number of 
subjects with topical Corticosteroid use on Study Day 1.

NSAIDs use on Study Day 1 (Yes or No)
Only NSAIDs medication records with a start date prior to Study Day 1 and an end date 
on or after Study Day 1 or missing will be used for counting the number of subjects with 
NSAIDs use on Study Day 1.

Duration of PsA from diagnosis (years)
Calculated as ((first dose date) – (date of initial diagnosis) + 1 day) / 365.25. If the date of 
initial diagnosis is incomplete, then the following rules will be applied:
■
missing day: use the first of the month
■
missing month: use January

Swollen joint count based on 66 joints (SJC66)

Tender joint count based on 68 joints (TJC68)

Swollen joint count based on 28 joints (SJC28)

Tender joint count based on 28 joints (TJC28)

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
SF-36v2 physical component summary (PCS) score

SF-36v2 mental component summary (MCS) score

FACIT-Fatigue 

LDI: Leeds Dactylitis Index in subjects with dactylitis at Baseline

SPARCC Enthesitis Index: Spondyloarthritis Research Consortium of Canada Enthesitis 
Index in subjects with enthesitis at Baseline

LEI: Leeds Enthesitis Index in subjects with enthesitis at Baseline

Patient’s Global Assessment of Psoriatic Arthritis Pain Intensity (PGAPI) (by VAS)

PASI: Psoriasis Area and Severity Index in subjects with psoriasis covering >=3% of the 
BSA at Baseline

PhGAP: Physician’s Global Assessment of Psoriasis in subjects with psoriasis covering 
>=3% of the BSA at Baseline

mNAPSI: Modified Nail Psoriasis Severity Index in subjects with psoriatic nail involvement 
at Baseline

PsAID-12: 12-item Psoriatic Arthritis Impact of Disease 

DAS28 (CRP): Disease Activity Score 28 by CRP 

DAPSA: Disease Activity in Psoriatic Arthritis

PASDAS: Psoriatic Arthritis Disease Activity Score

Tender dactylitis count (TDC) in subjects with dactylitis at Baseline

Patients’ global assessment of disease activity (PGADA)

Physician’s global assessment of disease activity (PhGADA)

High-Sensitivity C-reactive Protein (hsCRP)

hsCRP (>= 6mg/L or <6mg/L)
These baseline disease characteristics will be summarized by treatment group and overall using 
descriptive statistics for continuous variables and using number and percentage of subjects for 
categorical variables. The summary of these baseline characteristics will be provided for the 
Safety Analysis Set. No formal statistical testing is planned.
A by-subject listing of baseline disease characteristics will be provided by subject ID number in 
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5.3.
Medical History
Medical history collected at screening will be coded using the current version of Medical 
Dictionary for Regulatory Activities (MedDRA).
Medical history will be summarized by system organ class (SOC), preferred term (PT), treatment 
group, and overall. Subjects who report 2 or more medical history items that are coded to the 
same SOC and/or PT will be counted only once by the unique coded term in the summary.
The summary will be provided for the Safety Analysis Set. No formal statistical testing is 
planned.
A by-subject listing of medical history will be provided by subject ID number in ascending 
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6.
EFFICACY ANALYSES
6.1.
General Considerations
The primary analysis set for efficacy analyses will be the FAS, defined in Section 3.1.2.
Due to study early termination and insufficient number of subjects enrolled, all the hypothesis 
testings performed and p-values reported will be nominal, and, unless specified otherwise, all the 
confidence intervals will be calculated based on the nominal level of 95%. The results need to be 
interpreted with caution.
Efficacy analysis will be conducted on all available data during the Main Study phase (including 
data collected through the Week 16 visit after study drug discontinuation). 
Estimands:
Treatment policy estimand is defined for the primary and key secondary as well as other 
secondary efficacy endpoints and will be the primary estimand for all the corresponding efficacy 
analyses:
1) Population: Subjects in the FAS.
2) Variable / endpoint: Primary and key secondary endpoints as well as other secondary 
endpoints (see details in subsequent Sections).
3) Strategy to address intercurrent events: include all on-study data regardless of protocol 
violations, use of rescue medication, change in background medication, and study drug 
discontinuation.
4) Population-level summary: treatment difference in the percentage of subjects meeting 
specific criteria for response defined by binary efficacy endpoints or mean treatment 
difference for continuous efficacy endpoints between each filgotinib group and placebo 
group or adalimumab group if applicable.
Selection of Efficacy Data in the Event of Multiple Records in an Analysis Visit Window
If multiple valid, nonmissing efficacy measurements exist in an analysis window, records will be 
chosen based on the following rules if a single value is needed:

The record closest to the nominal day for that visit will be selected.

If there are 2 records that are equidistant from the nominal day, or more than 1 record (with 
time known) on the selected day, the latest record will be taken.

If chronological order cannot be determined (e.g., more than 1 record on the same day with 
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Calculation of Composite Endpoints
For the calculation of composite endpoints including DAS28(CRP), ACR20/50/70, MDA, 
VLDA, PASDAS, DAPSA, PsARC, we use the following steps unless otherwise specified:

Step 1: Assign individual components to analysis visit windows defined in Section 3.7.2

Step 2: Within each analysis visit window, select the component-level data based on the rules 
for selecting efficacy data as above

Step 3: Calculate the composite endpoint based on the selected component-level data in 
Step 2.
Missing Data Consideration
Unless specified otherwise, below are the consideration for the missing data that will be used 
throughout the efficacy analyses:
Observed case (OC): Missing values remain missing. For the categorical composite endpoints, in 
the case that some components are missing, the composite endpoint assessment will be derived 
based on the nonmissing components. If nonmissing components are not sufficient to determine 
final composite endpoint, then the composite endpoint will be set as missing. For continuous 
composite endpoints, if any components are missing, the composite endpoints will be set as 
missing.
If a subject only has baseline measurements, OC analyses will not include this subject.
For subjects who were re-randomized, the baseline value for the LTE phase will be the last 
nonmissing measurement obtained on or prior to the first dose date of filgotinib in the LTE. The 
change from baseline at analyses visits during LTE phase will be assessed from the 
re-randomized baseline of the LTE phase. The evaluation of response at analysis visits during 
LTE phase will be assessed from the re-randomized baseline of the LTE phase.
6.2.
Primary Efficacy Endpoint
The primary efficacy endpoint is the proportion of subjects who achieve ACR20 response at 
Week 12.
6.2.1.
Definition of the Primary Efficacy Endpoint
6.2.1.1.
ACR20
A subject achieves ACR20 response when this subject has

≥ 20% improvement from baseline in TJC68, AND

≥ 20% improvement from baseline in SJC66, AND


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
≥ 20% improvement from baseline in at least 3 of the following 5 items:
PGADA (0 – 100 visual analog scale (VAS))
PhGADA (0 – 100 VAS)
HAQ-DI’s pain assessment (0 – 100 VAS)
Patient’s assessment of physical function as measured by HAQ-DI score
hsCRP
Percent improvement from baseline at a postbaseline visit is calculated as follows for all 
7 components mentioned above:
%improvement = baseline value ― postbaseline value
baseline value
× 100
If the baseline value is 0 then the percent improvement from baseline is set to missing. In the 
case that some ACR20 components are missing, the ACR20 assessment will be based on the 
nonmissing components. If nonmissing components are not sufficient to determine ACR20 
response, then the ACR20 response will be considered as missing.
6.2.1.2.
ACR Components
6.2.1.2.1.
Tender/Swollen Joint Counts (TJC/SJC)
TJC68 and SJC66 will be collected during the course of the study. The assessment for each joint 
will be from the following selections: Normal, Tender, Swollen, Tender and Swollen or Not able 
to evaluate.
Individual joint with missing/non-evaluable assessment will not be imputed. If at least half of the 
joints are assessed and evaluable at a given visit, the prorated tender and swollen joint counts 
will be calculated using the following formula: 
TJC68 =  
Total number of tender joints
68 ―  (Number of missing/nonevaluable joints out of 68 joints) × 68
SJC66 =  
Total number of swollen joints
66 ―  (Number of missing/nonevaluable joints out of 66 joints) × 66


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If less than half of joints are assessed and evaluable at a given visit, joint counts are treated as 
missing for that visit.
A more abbreviated assessment considering 28 joints as listed in Table 6-1 for both tenderness 
and swelling will also be conducted (as part of the TJC68 and SJC66 assessment), denoted as 
TJC28 and SJC28, respectively.
Table 6-1.
Composition of the 28 Joints
Joints
Number
Shoulder Joints (Left and Right)
2
Elbow Joints (Left and Right)
2
Wrist Joints (Left and Right)
2
Metacarpophalangeal Joints I-V (Left and Right) – hands only
10
Proximal Interphalangeal Joints I-V (Left and Right) – hands only
10
Knee Joints (Left and Right)
2
If there exist non-evaluable or missing joints among the 28 joints, similar prorated tender and 
swollen joint counts will be calculated as follows:
TJC28 =  
Total number of tender joints
28 ―  (Number of missing/nonevaluable joints out of 28 joints) × 28
SJC28 =  
Total number of swollen joints
28 ―  (Number of missing/nonevaluable joints out of 28 joints) × 28
If less than half of the 28 joints are assessed and evaluable at a given visit, TJC28 and SJC28 are 
treated as missing for that visit.
6.2.1.2.2.
Patient’s Global Assessment of Disease Activity (PGADA)
PGADA is performed by patients. It is based on a 0 – 100 VAS, with a score of 0 indicating 
“very well” and 100 indicating “very poor” to the question “Considering all the ways psoriatic 
arthritis affects you, how well are you doing today?”. 
6.2.1.2.3.
Physician’s Global Assessment of Disease Activity (PhGADA)
PhGADA is performed by physicians. It is based on a 0 – 100 VAS with 0 indicates “no disease 
activity” and 100 indicates “maximum disease activity”.


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6.2.1.2.4.
Health Assessment Questionnaire Disability Index (HAQ-DI) 
The HAQ-DI score is defined as the average of the scores of eight functional categories (dressing 
and grooming, arising, eating, walking, hygiene, reach, grip, and other activities), administered 
by the subject. Responses in each functional category are collected as: without any difficulty; 
with some difficulty; with much difficulty; unable to do a task in that area and with or without 
aids or devices. The HAQ-DI score ranges from 0 (no disability) to 3 (completely disabled), 
when 6 or more categories are nonmissing. Detailed algorithm for calculating HAQ-DI score is 
described in Appendix 1.
HAQ-DI also includes a separate pain assessment and subject will be requested to mark the 
severity of the pain in the past week on a 0-100 VAS, with 0 indicating “no pain” and 
100 indicating “severe pain”.
6.2.2.
Primary Analysis of the Primary Efficacy Endpoint
To test for superiority of filgotinib 200 mg or filgotinib 100 mg group versus placebo control 
group in proportion of subjects who achieve ACR20 at Week 12, a logistic regression analysis 
with treatment groups and stratification factors in the model will be used. The model will include 
all treatment groups. Missing data on the ACR20 response rate at Week 12 will be imputed using 
multiple imputation (MI) assuming missing at random (MAR):

The MI procedure replaces each missing binary ACR20 value with a set of plausible values 
that represent the uncertainty about the right value to impute. Twenty imputed datasets will 
be generated with starting seed 12345. These multiple imputed data sets are then analyzed by 
using the same method for the primary analysis for complete data as specified above. The 
results from each set of imputed data sets will then be combined using Rubin’s rule 
{Rubin 1987}. The stratification factors and treatment groups will be included in the 
imputation model as covariates and all available data at post-baseline visits up to Week 16 
visit will be included in the longitudinal model.
The p-value from the logistic regression model with MI for testing the superiority of filgotinib 
200 mg or filgotinib 100 mg as compared to placebo will be provided. The 2-sided 
95% confidence interval (CI) of the ACR20 response rate at Week 12 based on MI method will 
be provided for each treatment group. In addition, treatment difference in ACR20 response rate 
at Week 12 between each filgotinib dose group and placebo group along with its 95% CI 
calculated based on MI method will be provided. 


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6.3.
Key Secondary Efficacy Endpoints
The key secondary efficacy endpoints are:

The proportion of subjects who achieve ACR50 response at Week 12

Change from Baseline in HAQ-DI at Week 12

Change from Baseline in SF-36v2 physical component summary (PCS) at Week 16

Change from Baseline in LEI at Week 16, in subjects with enthesitis at Baseline

The proportion of subjects who achieve PASI75 response at Week 16, in subjects with 
psoriasis covering ≥3% of the BSA at Baseline

The proportion of subjects who achieve MDA response at Week 16

Change from Baseline in FACIT-Fatigue at Week 16

Change from Baseline in LDI at Week 16, in subjects with dactylitis at Baseline
6.3.1.
Definition of Key Secondary Efficacy Endpoints
6.3.1.1.
ACR50
ACR50 is similarly defined as ACR20 (see Section 6.2.1), except that the improvement threshold 
from Baseline is 50%.
6.3.1.2.
36-Item Short-form Health Survey (SF36v2)
The SF-36 Version 2 is a 36-item, self-reported, generic, comprehensive, and health-related 
quality of life questionnaire that yields an 8 health domains (physical functioning, role-physical, 
bodily pain, general health, vitality, social functioning, role-emotional, and mental health). Each 
domain is scored by summing the individual items and transforming the scores into a 0 to 
100 scale with higher scores indicting better health status or functioning. In addition, 2 summary 
scores, the physical component summary (PCS) score and the mental component summary 
(MCS) score will be evaluated based on the 8 SF-36 domains.
6.3.1.3.
Enthesitis Assessments: Leeds Enthesitis Index (LEI)
The enthesitis examination by LEI is based on 6 anatomical sites: medial femoral condyle 
(left and right), lateral epicondyle (left and right) and the achilles tendon insertion (left and 
right). Enthesitis at each site was scored on a dichotomous basis: 0 means Enthesitis Absent and 
1 means Enthesitis Present. 
LEI is derived as the sum of the enthesitis score over the 6 sites mentioned above. 
If there are missing items, then available data are used to derive LEI.
The summaries and analysis of LEI will be conducted on the FAS subjects with enthesitis at 
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6.3.1.4.
Psoriasis Area and Severity Index (PASI)
PASI score is used to measure the severity and extent of psoriasis. The representative site of 
psoriasis is selected for each body region (head and neck (h), upper limb (u), trunk (t) and lower 
limbs (l)), and are separately scored by using 3 parameters, erythema (redness) (E), induration 
(thickeness) (I) and desquamation (scaling) (D), each of which is graded on a severity scale of 
0 to 4 (0 = none, 1 = mild, 2 = moderate, 3 = severe and 4 = very severe). The area-wise 
percentage involvement of the involved sites (head and neck (Ah), upper limbs (Au), trunk (At), 
and lower limbs (Al)) is calculated as: 0 = no involvement, 1 = >0–< 10%; 2 = 10 – < 30%; 
3 = 30 – < 50%; 4 = 50 – < 70%; 5 = 70 – < 90%; and 6 = 90 – 100%. 
The final formula for PASI score is: 
PASI 
=  0.1 ×  (Eh +  Ih +  Dh) ×  Ah +  0.2 ×  (Eu +  Iu +  Du) × Au +  0.3 ×  
(Et +  It +  Dt) ×  At +  0.4 ×  (El +  Il +  Dl) ×  Al
The PASI score ranges between 0 (no disease) and 72 (maximal disease), but is considered 
unreliable when BSA < 3%.
If any of the components is missing, then PASI score remains missing. 
Percent improvement from baseline at a postbaseline visit is defined the same as in 
section 6.2.1.1. If the baseline value is 0 then the percent improvement from baseline is set to 
missing.
PASI75 response is defined for subjects achieved 75% improvement from Baseline in PASI 
score.
The summaries and analysis of PASI score will be conducted on the FAS subjects with psoriasis 
covering at least 3% of the BSA at Baseline. 
6.3.1.5.
Minimal Disease Activity (MDA)
MDA is a measure to indicate disease remission, and is based on a composite score of 
7 domains. 
A subject will be classified as having achieved MDA when at least 5 out of 7 of the following 
criteria are met.

TJC68 ≤ 1,

SJC66 ≤ 1,


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
PASI ≤ 1 for subjects with a Baseline psoriasis covering at least 3% of the BSA (or for 
subjects with a Baseline psoriasis covering BSA < 3%, this criterion is considered met),

Patent’s Global Assessment of PsA pain intensity (PGAPI) score ≤ 15 (0 – 100 VAS),

PGADA ≤ 20 (0 – 100 VAS), 

HAQ-DI ≤ 0.5,

Leeds Enthesitis Index ≤ 1 for subjects with enthesitis at Baseline (or for subjects without 
enthesitis at Baseline, this criterion is considered met).
In the case that some of the MDA components are missing, the MDA assessment will be based 
on the nonmissing components. If nonmissing components are not sufficient to determine the 
MDA response, then the MDA response will be considered as missing.
6.3.1.6.
FACIT-Fatigue
The FACIT-Fatigue scale is a brief, 13-item, symptom-specific questionnaire that specifically 
assesses the self-reported severity of fatigue and its impact upon daily activities and functioning 
in the past 7 days. The FACIT-Fatigue uses 0 (“not at all”) to 4 (“very much”) numeric rating 
scales. Negatively stated items are reversed by subtracting the response from “4” before being 
added to obtain a total score. Scores range from 0 to 52 with higher scores indicating less fatigue. 
In the case of missing response for some items in the questionnaire, if at least half of the items 
(i.e., ≥ 7 of 13 items) were answered at a given visit, the prorated score will be calculated and 
used in the analysis.
The FACIT-Fatigue scale and scoring guidelines are in Appendix 2.
6.3.1.7.
Dactylitis Assessments: Leeds Dactylitis Index (LDI) 
LDI measures the ratio of the circumference of the affected digit to the circumference of the digit 
on the contralateral hand or foot using a Leeds Dactylometer. 
LDI score is calculated as follows:
LDI score of a dactylitic finger/toe =  
A
B ―  1 × 100
× C
where 
A = circumference of the dactylitic finger/toe (mm)
B = circumference of the contralateral digit (mm)
C = tenderness score (0 = no tenderness, 1 = tender)
{[(-) ] 
} 


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If both ipsilateral and contralateral digits are thought to be dactylitic, then the reference range 
(given at the foot of the Dactylitis Score Sheet as in Protocol Appendix 25) will be used as the 
comparator (i.e., B in the above formula). 
Binary tenderness score is used in LDI score calculation due to lack of reliability in the original 
Ritchie index. {Healy 2007}
Total LDI score equals to the sum of the non-negative individual LDI scores across all fingers 
and toes. Negative individual LDI scores will not be included in the total LDI score. 
If there are missing fingers or toes, then the missing individual scores for those fingers or toes 
will not be included in the total LDI score. For subjects with dactylitis status absent for all the 
fingers and toes, their total LDI scores will be set as 0, and the tenderness score for each finger 
and toe will also be set as 0.
The summaries and analysis of LDI will be conducted on the FAS subjects with dactylitis at 
Baseline.
6.3.2.
Analysis Methods for Key Secondary Efficacy Endpoints
For the superiority test of filgotinib 200 mg or filgotinib 100 mg group versus placebo control 
group in binary key secondary endpoints such as the ACR50 response rate at Week 12, the 
PASI75 response rate at Week 16 in subjects with psoriasis covering ≥3% of the BSA at 
Baseline and the MDA response rate at Week 16,  the observed response rate and 2-sided 
95% CI based on normal approximation with continuity correction will be provided by visit. 
Non-stratified response rate difference along with its 95% CI calculated based on the normal 
approximation with continuity correction will be provided. Appendix 4 provides sample SAS 
models statements for constructing the confidence interval for the proportion. In addition, the 
p-value based on the logistic regression model same as the one used in section 6.2.2 with 
observed cases for testing the superiority of filgotinib 200 mg or filgotinib 100 mg as compared 
to placebo will be provided as well. In case of limited data leading to improper use of logistic 
model, the p-value will not be provided.
For non-inferiority test of filgotinib 200 mg or filgotinib 100 mg group versus adalimumab group 
in the ACR20 response rate at Week 12, the approach proposed by {Liu 2014} will be used to 
demonstrate that each filgotinib dose preserves more than 50% of the effect of adalimumab on 
the response rate of ACR20 at Week 12. Let 𝜋𝑇, 𝜋𝐶 and 𝜋𝑃 denote the true response rates of 
ACR20 for filgotinib, adalimumab and placebo, respectively, at Week 12, with corresponding 
variances 𝜎2
𝑇,  𝜎2
𝐶 and 𝜎2
𝑃. The non-inferiority hypotheses are
𝐻0,𝑁𝐼 : 
𝜋𝑇― 𝜋𝑃
𝜋𝐶― 𝜋𝑃 ≤ 0.5
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𝐻1,𝑁𝐼 : 
𝜋𝑇― 𝜋𝑃
𝜋𝐶― 𝜋𝑃 > 0.5
According to {Liu 2014}, the test statistics for non-inferiority (filgotinib preserves more than 
50% of the effect of adalimumab) is 
𝑍𝑁𝐼=
𝜋𝑇― 0.5𝜋𝐶― (1 ― 0.5)𝜋𝑃
𝜎2𝑇+ 0.52𝜎2𝐶+ (1 ― 0.5)2𝜎2𝑃.
Note that the “hat” (⌃) denotes the estimated values of each parameter at Week 12. Missing data 
will be imputed using multiple imputation (MI) assuming that missing data are missing at 
random (MAR), which will follow the same method as described for the primary endpoint.
For the superiority test of filgotinib 200 mg or filgotinib 100 mg group versus placebo control 
group in continuous key secondary endpoints such as the change from baseline in HAQ-DI at 
Week 12, the change from Baseline in SF-36v2 PCS at Week 16, the change from Baseline in 
LEI at Week 16 for subjects with enthesitis at Baseline, the change from Baseline in 
FACIT-Fatigue at Week 16 and the change from Baseline in LDI at Week 16 for subjects with 
dactylitis at Baseline, a mixed-effect model repeated measures (MMRM) analysis that includes 
data at postbaseline visits through Week 16 will be applied. Subjects that have a baseline value 
and at least 1 postbaseline value are included in the analysis. The MMRM models will be used to 
evaluate treatment effect on change score from Baseline, with baseline value, stratification 
factors, treatment, visit, and treatment by visit interaction included as fixed effects and subject 
being the random effect. The MMRM model will include all treatment groups. An unstructured 
variance-covariance matrix will be used. The Kenward-Roger method will be used to estimate 
the degrees of freedom. Missing data will not be otherwise imputed using the MMRM approach. 
The least squares (LS) means and 95% CIs of the difference in mean change from Baseline 
between each filgotinib dose group and placebo group from MMRM will be provided at all the 
visits in Main study including Week 12 and Week 16.
In case of limited data leading to improper use of MMRM model, the descriptive statistics 
(sample size, mean, SD, median, Q1, Q3, minimum, and maximum) by treatment will be used 
for the continuous key secondary endpoints.
6.4.
Other Secondary Efficacy Endpoint
Other secondary endpoints will be evaluated at all scheduled or applicable time points in the 
Main Study other than the time points that are already specified in the primary and key 
secondary endpoints.
The other secondary endpoints include:

Change from Baseline in PASDAS
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
MDA response

VLDA response

Change from Baseline in DAPSA 

Change from Baseline in PhGAP, in subjects with psoriasis covering ≥3% of the BSA at 
Baseline

Change from Baseline in mNAPSI, in subjects with psoriatic nail involvement at Baseline

Change from Baseline in LEI, in subjects with enthesitis at Baseline

Change from Baseline in PsAID-12

PASDAS low disease activity (LDA, i.e. PASDAS ≤3.2)

PASDAS remission (i.e. PASDAS ≤1.9)

ACR20 response

ACR50 response

ACR70 response

Change from Baseline in individual components of the ACR response criteria

Change from Baseline in DAS28(CRP)

DAS28(CRP) LDA

DAS28(CRP) remission

Time to achieve DAS28(CRP) LDA

DAPSA LDA

DAPSA remission

Time to achieve DAPSA LDA

PsARC response

Change from Baseline in PASI, in subjects with psoriasis covering ≥3% of the BSA at 
Baseline

PASI50 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

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
PASI90 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

PASI100 response, in subjects with psoriasis covering ≥3% of the BSA at Baseline

Change from Baseline in SPARCC Enthesitis Index, in subjects with enthesitis at Baseline

Change from Baseline in LDI, in subjects with dactylitis at Baseline

Change from Baseline in tender dactylitis count (TDC), in subjects with dactylitis at Baseline

Change from Baseline in HAQ-DI

Change from Baseline in FACIT-Fatigue

Change from Baseline in SF-36v2 PCS and mental component score (MCS)
6.4.1.
Definition of Other Secondary Endpoints
6.4.1.1.
Tender Dactylitis Count (TDC)
Tender score (0 = no tenderness, 1 = tender, 2 = tender and wince, 3 = tender and withdraw) is 
collected for Dactylitis Assessments on the Dactylitis Score Sheet that was used for calculation 
of LDI total score. 
Tender dactylitis count (TDC) equals the number of tender fingers and toes (tendor score >0). 
For subjects with dactylitis status absent for all the fingers and toes, the TDC will be set as 0. 
This score is used as a component of the PASDAS.
If there are missing fingers or toes, then the missing count for those fingers or toes will not be 
included in the TDC. 
6.4.1.2.
Psoriatic Arthritis Disease Activity Score (PASDAS), PASDAS Low Disease 
Activity (LDA) and PASDAS remission
PASDAS =   0.18 ×
PhGADA +  0.159 ×
PGADA – 0.253 ×
PCS +  0.101 × Ln(SJC66 +  1) +  0.048
× Ln(TJC68 +  1) +  0.23 × Ln(LEI +  1) +  0.377 × Ln(TDC +  1) +  0.102 × Ln(CRP +  1) 
+  2 × 1.5
where
PhGADA = Physician’s Global Assessment of Disease Activity (0 – 100 VAS);
PGADA = Patient’s Global Assessment of Disease Activity (0 – 100 VAS);
PCS = Physical Component Score of the SF-36;
LEI = Leeds Enthesitis Index, derived from the enthesitis assessments;
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TDC = Tender Dactylitis Count from the LDI;
CRP is in the unit of mg/L.
A lower score indicates better function.
If a subject did not have dactylitis at baseline and hence no dactylitis assessments are collected 
post-baseline, then it is assumed that TDC = 0 at baseline and all post-baseline visits for 
calculating PASDAS.
If a subject did not have enthesitis at baseline and hence no enthesitis assessments are collected 
post-baseline, then it is assumed that LEI = 0 at baseline and all post-baseline visits for 
calculating PASDAS.
If any of the components is missing, then PASDAS remains missing.
PASDAS LDA is defined as PASDAS≤3.2; PASDAS remission is defined as PASDAS≤1.9.
6.4.1.3.
Very Low Disease Activity (VLDA)
VLDA is defined based on the same 7 criteria as in MDA. A subject will be classified as having 
achieved VLDA when all 7 out of 7 of the criteria are met. In the case that some of the VLDA 
components are missing, the VLDA assessment will be based on the nonmissing components. If 
nonmissing components are not sufficient to determine the VLDA response, then the VLDA 
response will be considered as missing.
6.4.1.4.
Disease Activity Index for Psoriatic Arthritis (DAPSA), DAPSA LDA, DAPSA 
remission and Time to Achieve DAPSA LDA
DAPSA = TJC68 + SJC66 + PGADA (0 – 100 VAS)/10 + PGAPI (0 – 100VAS)/10 + CRP 
(mg/dL).
where
PGADA = Patient’s Global Assessment of Disease Activity (0 – 100 VAS);
PGAPI = Patient’s Global Assessment of PsA Pain Intensity (0 – 100 VAS);
CRP is in unit of mg/dL.
If any of the components is missing, then DAPSA remains missing.
The derived DAPSA binary parameters include:

DAPSA remission: DAPSA ≤ 4,

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The time to achieve DAPSA LDA is defined as:
Date of first (DAPSA ≤ 14) – First dose date of any study drug + 1
For each subject included in the analysis, all available measurement for DAPSA will be 
considered for the time to achieve DAPSA LDA based on the treatment policy estimand.
The time to achieve DAPSA LDA can be derived for the subject in each treatment group based 
the data during Main study phase. If the DAPSA LDA is not achieved during Main study phase, 
the time to achieve DAPSA LDA will be censored at the last nonmissing DAPSA assessment 
date during Main study phase. If the component scores of DAPSA are at different dates for a 
visit, the latest date will be used for the derivation of time to achieve DAPSA LDA. 
6.4.1.5.
Physician’s Global Assessment of Psoriasis (PhGAP)
The physician will give a score on the subject’s psoriasis disease activity, according to the 
following grades:

Induration (I) (0 – 5 scale, averaged over all lesions),

Erythema (E) (0 – 5 scale, averaged over all lesions),

Scaling (S) (0 – 5 scale, averaged over all lesions).
The sum of the 3 grades will be divided by 3, i.e., = (I + E + S)/3, and rounded to the nearest 
integer (i.e., 0, 1, 2, 3, 4, 5) to obtain the total average score. Physician’s Static Global 
Assessment (0 – 5 scale) will be based on the total average score: 0 = cleared; 1 = minimal; 
2 = mild; 3 = moderate; 4 = marked; and 5 = severe. 
If any of the grades above is missing, then the score remains missing.
Physician’s Static Global Assessment (0-5 scale) will be the endpoint for analysis, which will be 
considered as continuous endpoint. The summaries and analyses will be conducted on the FAS 
subjects with psoriasis covering at least 3% of the BSA at Baseline.
6.4.1.6.
Modified Nail Psoriasis Area and Severity Index (mNAPSI)
mNAPSI is used to assess each nail abnormality for each of subject’s nail. Three features or 
groups of features (pitting, onycholysis together with oil-drop dyschromia, and crumbling) of 
each fingernail will be graded on a scale from 0 to 3. Four features (leukonychia, splinter 
hemorrhages, hyperkeratosis, and red spots in the lunula) will be graded as either present (1) or 
absent (0) for each fingernail. Each finger will have a score between 0 and 13. The total 
mNAPSI score is the sum of all abnormalities individual score across all fingers, and the total 
mNAPSI score ranges from 0 to 130.
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The summaries and analyses of nail psoriasis will be conducted on the FAS subjects who had 
psoriatic nail involvement at Baseline.
6.4.1.7.
12-item Psoriatic Arthritis Impact of Disease (PsAID-12)
The PsAID is calculated based on 12 numerical rating scales (NRS) questions. Each NRS is 
assessed as number between 0 and 10.
PsAID final value
=  (PsAID1 (pain) NRS ×  3) +  (PsAID2 (fatigue) NRS ×  2) +  
(PsAID3 (skin) NRS ×  2) +  (PsAID4 (work 𝑎𝑛𝑑 / 𝑜𝑟 leisure activities) NRS
×  2) +  (PsAID5 (function) NRS ×  2) +  (PsAID6 (discomfort) NRS ×  2) +  (
PsAID7 (sleep) NRS ×  2) +  (PsAID8 (coping) NRS × 1) +  (PsAID9 (anxiety)
 NRS ×  1) + (PsAID10 (embarrassment) NRS ×  1) +   (PsAID11 (social life)
 NRS ×  1) + (PsAID12 (depression) NRS ×  1)
The total is divided by 20. Thus the range of the final PsAID value is 0-10 where higher figures 
indicate worse status.
If one of the 12 NRS values composing the PsAID is missing, the imputation is as follows: 
calculate the mean value of the 11 other (nonmissing) NRS (range, 0 – 10), impute this value for 
the missing NRS. Then, calculate the PsAID as explained above. If 2 or more of the NRS are 
missing, the PSAID is considered missing value (no imputation).
6.4.1.8.
ACR70
ACR70 is similarly defined as ACR20 (see Section 6.2.1), except that the improvement threshold 
from Baseline is 70%.
6.4.1.9.
Disease Activity Score for 28 joint count using C-reactive protein 
(DAS28 (CRP)), DAS28 (CRP) LDA, DAS28 (CRP) remission and Time to 
Achieve DAS28(CRP) LDA
The DAS28(CRP) score is calculated as follows:
DAS28(CRP) = 0.56 TJC28 +0.28 SJC28 +0.36ln(CRP + 1) +0.014 × PGADA + 0.96,
where 
Ln(CRP + 1) is the natural logarithm of (CRP value [mg/L] + 1);
PGADA is on 0 – 100 scale.
Higher DAS28 (CRP) value indicates more severe disease activity.
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If any of the components is missing, the DAS28(CRP) will be set as missing.
The derived DAS28(CRP) binary parameters include:

DAS28(CRP) remission: DAS28(CRP) < 2.6,

DAS28(CRP) LDA: DAS28(CRP) ≤ 3.2.
The time to achieve DAS28(CRP) LDA is defined as:
Date of first [DAS28(CRP) ≤ 3.2] – First dose date of any study drug + 1
For each subject included in the analysis, all available measurement for DAS28(CRP) will be 
considered for the time to achieve DAS28(CRP) LDA based on the treatment policy estimand.
The time to achieve DAS28(CRP) LDA can be derived for the subject in each treatment group 
based the data during Main study phase. If the DAS28(CRP) LDA is not achieved during Main 
study phase, the time to achieve DAS28(CRP) LDA will be censored at the last nonmissing 
DAS28(CRP) assessment date during Main study phase. If the component scores of 
DAS28(CRP) are at different dates for a visit, the latest date will be used for the derivation of 
time to achieve DAS28(CRP) LDA. 
6.4.1.10.
Psoriatic Arthritis Response Criteria (PsARC) response
PsARC responder is defined as having an improvement in at least 2 of the 4 factors (with at least 
one factor being a joint count) and no worsening in the remaining factors:

TJC68 (improvement defined as a decrease from baseline of at least 30%),

SJC66 (improvement defined as a decrease from baseline of at least 30%),

PGADA (0 – 100 VAS, improvement defined as a decrease from baseline of at least 20),

PhGADA (0 – 100 VAS, improvement defined as a decrease from baseline of at least 20).
In the case that some of the PsARC components are missing, the PsARC assessment will be 
based on the nonmissing components. If nonmissing components are not sufficient to determine 
the PsARC response, then the PsARC response will be considered as missing.
6.4.1.11.
PASI50, PASI90, PASI100
PASI50, PASI90 and PASI100 response are defined similarly as PASI75, except that the 
improvement threshold from baseline are 50%, 90% and 100% in PASI score, respectively.


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6.4.1.12.
Spondyloarthritis Research Consortium of Canada (SPARCC) Enthesitis Index
The enthesitis examination is based on the 16 anatomical sites: the medial epicondyle (left and 
right), the lateral epicondyle (left and right), the supraspinatus insertion (left and right), the 
bilateral greater trochanter (left and right), the quadriceps tendon insertion into superior border of 
patella (left and right), the patellar ligament insertion into inferior pole of patella or tibial 
tuberosity (left and right), the achilles tendon insertion (left and right), and the plantar fascia 
insertion (left and right). Enthesitis at each site was scored on a dichotomous basis: 0 means 
Enthesitis Absent and 1 means Enthesitis Present.
SPARCC Enthesitis Index is derived as the sum of the enthesitis score over the 16 sites 
mentioned above.
If there are missing items, then available data are used to derive SPARCC Enthesitis Index.
The summaries and analyses of SPARCC Enthesitis Index will be conducted on the FAS subjects 
with enthesitis at Baseline.
6.4.2.
Analysis Methods for Other Secondary Endpoints
The FAS will be used for all summaries and analyses of other secondary efficacy endpoints.
For the binary endpoints of the ACR20 response, the ACR50 response, the PASI75 response in 
subjects with psoriasis covering ≥3% of the BSA at Baseline and the MDA response, for subjects 
with observed outcome, the similar analysis as the key secondary endpoint analyses described in 
Section 6.3.2 will be applied. The proportions of subjects achieving above endpoints (observed 
case) will be plotted over time during Main study by treatment and by visit.
For all the other binary endpoints, only above mentioned observed response rate, 2-sided 95% CI 
and non-stratified response rate difference along with its 95% CI will be provided by visit.
For all the continuous endpoints, absolute value and change from Baseline will be summarized 
using descriptive statistics (sample size, mean, SD, median, Q1, Q3, minimum, and maximum) 
by treatment and by visit. 
For the continuous endpoints of the change from baseline in HAQ-DI, the change from Baseline 
in SF-36v2 PCS, the change from Baseline in LEI for subjects with enthesitis at Baseline, the 
change from Baseline in FACIT-Fatigue and the change from Baseline in LDI for subjects with 
dactylitis at Baseline, plots of mean ± SD for change from baseline by visit will be presented.
For time to event analyses, Kaplan-Meier plot of each treatment group during Main study will be 
provided. Number of subjects having events and censored, KM estimates of median (95% CI), 
Q1, Q3, minimum and maximum of the time to events will be summarized by treatment group.
The by-subject listing of each endpoint and corresponding components, if available, including 
data during the Main Study and LTE phases will be provided.


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6.5.
Changes From Protocol-Specified Efficacy Analyses
Due to study termination and insufficient number of subjects enrolled, graphical approach of 
multiple test procedures will not be implemented, and only the nominal p values will be 
presented.
Due to small number of subjects available, for key secondary binary endpoints, logistic 
regression analyses may not be applicable. In such cases, no p-value will be provided. For key 
secondary continuous endpoints, MMRM analyses may not be applicable. In such cases, only 
descriptive summary statistics will be provided.
No sensitivity analyses will be performed. 


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7.
SAFETY ANALYSES
7.1.
Adverse Events and Deaths
7.1.1.
Adverse Event Dictionary
Clinical and laboratory adverse events (AEs) will be coded using the current version of 
MedDRA. System organ class (SOC), high-level group term (HLGT), high-level term (HLT), 
preferred term (PT), and lower-level term (LLT) will be provided in the AE dataset.
7.1.2.
Adverse Event Severity
Adverse events are graded by the investigator as Grade 1, 2, 3, 4, or 5 according to toxicity 
criteria specified in the protocol. The severity grade of events for which the investigator did not 
record severity will be categorized as “missing” for tabular summaries and data listings. The 
missing category will be listed last in summary presentation.
7.1.3.
Relationship of Adverse Events to Study Drug
Related AEs are those for which the investigator selected “Related” on the AE CRF to the 
question of “Related to Study Treatment.” Relatedness will always default to the investigator’s 
choice, not that of the medical monitor. Events for which the investigator did not record 
relationship to study drug will be considered related to study drug for summary purposes. 
However, by-subject data listings will show the relationship as missing.
7.1.4.
Serious Adverse Events
Serious adverse events (SAEs) will be identified and captured as SAEs if the AEs met the 
definitions of SAEs that were specified in the study protocol. SAEs captured and stored in the 
clinical database will be reconciled with the SAE captured in Gilead safety database before data 
finalization.
7.1.5.
Treatment-Emergent Adverse Events 
7.1.5.1.
Definition of Treatment-Emergent Adverse Events
Treatment-emergent adverse events (TEAEs) are defined as one or both of the following:

Any AEs with an onset date on or after the study drug start date and no later than 30 days 
after permanent discontinuation of study drug

Any AEs leading to premature discontinuation of study drug.
For subjects who entered LTE, TEAEs with an onset date prior to first dose date of any study 
drug for LTE will be allocated to the Main Study phase. TEAEs with an onset date on or after the 
first dose date of any study drug for LTE will be allocated to the LTE phase. 


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7.1.5.2.
Incomplete Dates
If the onset date of the AE is incomplete and the AE stop date is not prior to the first dosing date 
of study drug, then the month and year (or year alone if month is not recorded) of onset 
determine whether an AE is treatment emergent. The event is considered treatment emergent if 
both of the following 2 criteria are met:

The AE onset is the same as or after the month and year (or year) of the first dosing date of 
study drug, and

The AE onset date is the same as or before the month and year (or year) of the date 
corresponding to 30 days after the date of the last dose of study drug
An AE with completely missing onset and stop dates, or with the onset date missing and a stop 
date later than the first dosing date of study drug, will be considered to be treatment emergent. In 
addition, an AE with the onset date missing and incomplete stop date with the same or later 
month and year (or year alone if month is not recorded) as the first dosing date of study drug will 
be considered treatment emergent.
For subjects who entered LTE, an AE with incomplete onset date that is prior to the month and 
year (or year) of the first dose date of any study drug for LTE will be allocated to the Main Study 
phase. An AE with incomplete onset date that is after the month and year (or year) of the first 
dose date of any study drug for LTE will be allocated to the LTE phase.
In addition, an AE with completely missing onset date or incomplete onset date that is same as 
the month and year (or year) of the first dose date of any study drug for LTE, and stop date that 
is prior to the date (or month and year if day is not recorded; or year alone if month is not 
recorded) of the first dose date of any study drug for LTE, will be allocated to the Main Study 
phase. An AE with completely missing onset date or incomplete onset date that is same as the 
month and year (or year) of the first dose date of any study drug for LTE, and stop date that is 
missing, or the same as, or after the date (or month and year if day is not recorded; or year alone 
if month is not recorded) of the first dose of any study drug for LTE will be allocated to the LTE 
phase.
7.1.6.
Summaries of Adverse Events and Deaths
Treatment-emergent AEs will be summarized based on the Safety Analysis Set. 
7.1.6.1.
Summaries of AE Incidence 
The number and percentage of subjects who experienced at least 1 TEAE will be provided and 
summarized by SOC, HLT, PT, and treatment group. For other AEs described below, summaries 
will be provided by SOC, PT, and the treatment group: 

TEAE (by maximum severity)

TEAEs with Grade 3 or higher (by maximum severity) 


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
TE treatment-related AEs (by maximum severity)

TE treatment-related AEs with Grade 3 or higher (by maximum severity) 

TE SAEs

TE treatment-related SAEs 

TEAEs leading to premature discontinuation of any study drug

TEAEs leading to premature discontinuation of study

TE AEs leading to death (i.e., outcome of death)

TEAEs leading to temporary interruption of any study drug
A brief, high-level summary of the number and percentage of subjects who experienced at least 
1 TEAE in the categories described above will be provided by treatment group. All deaths 
observed in the Main Study will also be included in this summary.
Multiple events will be counted only once per subject in each summary. Adverse events will be 
summarized and listed first in alphabetic order of SOC (and HLT within each SOC if applicable), 
and then by PT in descending order of total frequency within each SOC. For summaries by 
severity grade, the most severe grade will be used for those AEs that occurred more than once in 
an individual subject during the study. 
In addition to the above summary tables, all TEAEs will be summarized by PT only, in 
descending order of total frequency.
In addition, data listings will be provided for the following:

All AEs, indicating whether the event is treatment emergent

All SAEs

All Deaths

All SAEs leading to death (i.e., outcome of death)

All AEs with severity of Grade 3 or higher

All AEs leading to premature discontinuation of any study drug

All AEs leading to premature discontinuation of study

All AEs leading to temporary interruption of any study drug


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7.1.7.
Adverse Events of Special Interest
Events of interest will be identified by the use of either SMQs or MedDRA search terms (MSTs). 
However, should additional cases not detected by the predefined search term listings identified 
during the clinical review process, these cases will also be reported by respective category.
7.1.7.1.
Adjudication Committee for Major Adverse Cardiovascular Events (MACE) and 
Thromboembolic Events
An independent adjudication committee governed by a charter will be set up to perform 
adjudication of potential MACE as well as thromboembolic events reported during the study. 
7.1.7.1.1.
Major Adverse Cardiovascular Events (MACE)
MACE will be comprised of cardiovascular (CV) death, non-fatal myocardial infarction (MI) 
and non-fatal stroke. To identify the MACE, the following potential cases identified will be 
adjudicated:

All deaths

Cardiovascular events (meeting serious criteria)

Myocardial infarction (NARROW)

Hospitalization for unstable angina

Transient ischemic attack

Stroke

Hospitalization for cardiac failure

Percutaneous coronary intervention
7.1.7.1.2.
Thromboembolic Events
Thromboembolism events will be comprised of arterial systemic thromboembolism events 
(ASTE) and venous thromboembolism events (VTE) associated with deep vein thrombosis 
(DVT) and/or pulmonary embolism (PE). To identify the thromboembolism events, the potential 
cases identified using the Embolic And Thrombotic Events SMQ search will be adjudicated.
The adjudication committee will review those potential MACE and thromboembolic events and 
related clinical data to determine whether a MACE or thromboembolism event has developed.  
The number and percentage of subjects with positively adjudicated MACE or thromboembolic 
events will be summarized by treatment group using PT.
By-subject listings for all randomized subjects who have potential MACE or thromboembolic 
events will be provided respectively.


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7.1.7.2.
Other Adverse Events of Special Interest
In addition to general safety parameters, MACE and Thromboembolic Events, safety information 
on other adverse events of special interest (AESIs) will also be analyzed. AESIs will be 
identified by laboratory results, SMQs, sponsor defined MSTs, or a combination of these 
methods as indicated below.

All infections (defined as all PTs in the Infections and Infestations SOC)

Serious infections (defined as all PTs in the Infections and Infestations SOC that are SAEs)

Infections of special interest as defined below 
a) Herpes zoster
b) Active tuberculosis 
c) Opportunistic infections

Malignancy (including lymphoma; excluding nonmelanoma skin cancer) 

Nonmelanoma skin cancer 

Gastrointestinal (GI) perforations 
The number and percentage of subjects with aforementioned events of special interest will be 
provided by the PT for each AE of special interests.
A by-subject listing for all subjects having AE of special interests at any time will be provided 
for each AE of special interest.
7.2.
Laboratory Evaluations
Laboratory data collected during the study will be analyzed and summarized using both 
quantitative and qualitative methods. Summaries of laboratory data will be provided for the 
Safety Analysis Set and will include data collected up to 30 days after the last dose date. 
The analysis will be based on values reported in conventional units. When values are below the 
LOQ, they will be listed as such, and the closest imputed value will be used for the purpose of 
calculating summary statistics as specified in Section 3.6. 
A baseline laboratory value will be defined as the last nonmissing measurement obtained on or 
prior to the date/time of first dose of any study drug. 


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For subjects who were re-randomized, the baseline laboratory value for the LTE phase will be 
the last available measurement obtained on or prior to the first dose date of filgotinib. The lab 
abnormalities after the first dose date of filgotinib will be assessed from the re-randomized 
baseline.
For subjects who entered LTE phase, the laboratory collected on or prior to the first dose date of 
any study drug for LTE will be allocated to Main Study phase. The laboratory collected after the 
first dose date of any study drug for LTE will be allocated to LTE phase.
A by-subject listing for laboratory test results will be provided by subject ID number and visit in 
chronological order for hematology, serum chemistry, and urinalysis separately. Values falling 
outside of the relevant reference range and/or having a severity grade of 1 or higher on the 
CTCAE severity grade will be flagged in the data listings, as appropriate.
No formal statistical testing is planned.
7.2.1.
Summaries of Numeric Laboratory Results
Descriptive statistics of Baseline values, values at each postbaseline visit and change from 
Baseline at each postbaseline visit will be provided by treatment group for the following 
laboratory tests:

Hematology
Hematocrit
Hemoglobin
Platelet count
Red blood cell (RBC) count
White blood cell (WBC) count
Mean corpuscular volume
Lymphocytes
Monocytes
Neutrophils
Eosinophils
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
Chemistry
Alkaline phosphatase (ALP)
Aspartate aminotransferase (AST)
Alanine aminotransferase (ALT)
Total bilirubin
Serum creatinine
Creatinine clearance by Cockcroft-Gault formula
Glucose

Lipid
Triglycerides
Total cholesterol
HDL
LDL
LDL/HDL ratio
Change from baseline to a postbaseline visit will be defined as the visit value minus the baseline 
value. The mean, median, Q1, Q3, minimum, and maximum values will be displayed to the 
reported number of digits; SD values will be displayed to the reported number of digits plus 1.
Median (Q1, Q3) of the observed values for these laboratory tests will be plotted using line plot 
by treatment group and visit.
In the case of multiple values in an analysis window, data will be selected for analysis as 
described in Section 3.7.3.
7.2.2.
Graded Laboratory Values
The CTCAE Version 5.0 will be used to assign toxicity grades (0 to 4) to laboratory results for 
analysis. Grade 0 includes all values that do not meet the criteria for an abnormality of at least 
Grade 1. For laboratory tests with criteria for both increased and decreased levels, analyses for 
each direction (i.e., increased, decreased) will be presented separately. 


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7.2.2.1.
Treatment-Emergent Laboratory Abnormalities
Treatment-emergent laboratory abnormalities are defined as values that increase at least 
1 toxicity grade from baseline at any postbaseline time point, up to and including the date of last 
dose of any study drug plus 30 days. 
For subjects who entered LTE, treatment-emergent laboratory abnormalities during Main study 
phase are defined as values increase at least 1 toxicity grade from the baseline at any 
postbaseline time point, up to and including the first dose date of study drug for LTE. 
Treatment-emergent laboratory abnormalities during LTE phase are defined as values that 
increase at least 1 toxicity grade from the baseline (re-randomized baseline for re-randomized 
subjects) at any postbaseline time point after first dose date of study drug for LTE, up to and 
including the date of last dose of any study drug plus 30 days.
If the relevant baseline laboratory value is missing, any abnormality of at least Grade 1 observed 
within the time frame specified above will be considered treatment emergent.
7.2.2.2.
Treatment-Emergent Marked Laboratory Abnormalities
Treatment-emergent marked laboratory abnormalities are defined as values that increase at least 
3 toxicity grade from baseline at any postbaseline time point, up to and including the date of last 
dose of any study drug plus 30 days. 
For subjects who entered LTE, treatment-emergent marked laboratory abnormalities during Main 
study phase are defined as values increase at least 3 toxicity grade from the baseline at any 
postbaseline time point, up to and including the first dose date of study drug for LTE. 
Treatment-emergent marked laboratory abnormalities during LTE phase are defined as values 
that increase at least 3 toxicity grade from the baseline (re-randomized baseline for re-
randomized subjects) at any postbaseline time point after first dose date of study drug for LTE, 
up to and including the date of last dose of any study drug plus 30 days.
If the relevant baseline laboratory value is missing, any Grade 3 or higher values observed within 
the timeframe specified above will be considered treatment emergent marked abnormalities.
7.2.2.3.
Summaries of Laboratory Abnormalities
Laboratory data that are categorical will be summarized using the number and percentage of 
subjects in the study with the given response at baseline and each scheduled postbaseline visit.
The following summaries (number and percentage of subjects) for treatment-emergent laboratory 
abnormalities will be provided by lab test and treatment group; subjects will be categorized 
according to the most severe postbaseline abnormality grade for a given laboratory test:

Graded laboratory abnormalities

Grade 3 or higher laboratory abnormalities

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For all summaries of laboratory abnormalities, the denominator is the number of subjects with 
nonmissing postbaseline values up to 30 days after last dosing date. 
By-subject listings of treatment-emergent Grade 3 or higher laboratory abnormalities and marked 
laboratory abnormalities will be provided separately by subject ID number and visit in 
chronological order. These listings will include all test results that were collected throughout the 
study for the lab test of interest, with all applicable severity grades or abnormal flags displayed.
7.2.3.
Liver-related Laboratory Evaluations
Liver-related abnormalities after initial study drug dosing will be examined and summarized 
using the number and percentage of subjects who were reported to have the following laboratory 
test values for postbaseline measurements:

Aspartate aminotransferase (AST): (a) > 3 times of the upper limit of reference range (ULN); 
(b) > 5 x ULN; (c) > 10 x ULN

Alanine aminotransferase (ALT): (a) > 3 x ULN; (b) > 5 x ULN; (c) > 10 x ULN

AST or ALT: (a) > 3 x ULN; (b) > 5 x ULN; (c) > 10 x ULN

Total bilirubin: > 2 x ULN

Alkaline phosphatase (ALP) > 1.5 x ULN

AST or ALT > 3 x ULN and total bilirubin: (a) > 1.5 x ULN; (b) > 2 x ULN
The summary will include data from all postbaseline visits up to 30 days after the last dose of 
study drug. For individual laboratory tests, subjects will be counted once based on the most 
severe postbaseline values. For both the composite endpoint of AST or ALT and total bilirubin, 
subjects will be counted once when the criteria are met at the same postbaseline visit date. The 
denominator is the number of subjects in the Safety Analysis Set who have nonmissing 
postbaseline values of all relevant tests at the same postbaseline visit date. A listing of subjects 
who met at least 1 of the above criteria will be provided.
7.2.4.
Complete Blood Count-Related Laboratory Evaluations
Complete blood count (CBC)-related abnormalities such as anemia, leucopenia, neutropenia, 
lymphopenia, and thrombocytopenia after initial study drug dosing will be examined and 
summarized using the number and percentage of subjects who were reported to have the 
following laboratory test values for postbaseline measurements:

Hemoglobin: (a) any postbaseline worsening CTCAE grade from baseline; (b) baseline value 
of less than Grade 3 and increase to Grade 3 or higher at worst postbaseline; (c) baseline 
value of less than Grade 3 and increase to Grade 4 at worst postbaseline

WBC count: (a) any postbaseline worsening CTCAE grade from baseline; (b) baseline value 
of less than Grade 3 and increase to Grade 3 or higher at worst postbaseline; (c) baseline 
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
Absolute neutrophil count: (a) any postbaseline worsening CTCAE grade from baseline; 
(b) baseline value of less than Grade 3 and increase to Grade 3 or higher at worst 
postbaseline; (c) baseline value of less than Grade 3 and increase to Grade 4 at worst 
postbaseline

Lymphocyte count: (a) any postbaseline worsening CTCAE grade from baseline; (b) baseline 
value of less than Grade 3 and increase to Grade 3 or higher at worst postbaseline; 
(c) baseline value of less than Grade 3 and increase to Grade 4 at worst postbaseline

Platelet count: (a) any postbaseline worsening CTCAE grade from baseline; (b) baseline 
value of less than Grade 3 and increase to Grade 3 or higher at worst postbaseline; 
(c) baseline value of less than Grade 3 and increase to Grade 4 at worst postbaseline
The summary will include data from all postbaseline visits up to 30 days after the last dose of 
any study drug.
7.3.
Body Weight and Vital Signs
Descriptive statistics will be provided by treatment group for body weight, BMI and vital signs 
(systolic and diastolic pressures (mmHg), pulse (beats/min)) as follows:

Baseline value

Values at each postbaseline visit

Change from baseline at each postbaseline visit
A baseline value will be defined as the last available value collected on or prior to the date/time 
of first dose of study drug. 
For subjects who were re-randomized, the baseline value for LTE phase will be defined as the 
last available value collected on or prior to the date/time of the first dose of study drug for LTE.
For subjects who entered LTE phase, the body weight, BMI and vital signs collected on or prior 
to the first dose date of any study drug for LTE will be allocated to Main Study phase. The body 
weight, BMI and vital signs collected after the first dose date of any study drug for LTE will be 
allocated to LTE phase.
Change from baseline to a postbaseline visit will be defined as the postbaseline value minus the 
baseline value. Body weight and vital signs measured at unscheduled visits will be included for 
the baseline value selection. 
In the case of multiple values in an analysis window, data will be selected for analysis as 
described in Section 3.7.3. No formal statistical testing is planned.
A by-subject listing of vital signs will be provided by subject ID number and visit in 
chronological order. In the same manner, a by-subject listing of body weight, height, and BMI 
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7.4.
Prior and Concomitant Medications
Medications collected at screening and during the study will be coded using the current version 
of the World Health Organization (WHO) Drug dictionary. 
All the analyses in this section will be performed for general prior/concomitant medications and 
PsA-specific prior/concomitant medications separately, unless otherwise specified.
7.4.1.
Prior Medications
Prior medications are defined as any medications taken before a subject took the first study drug.
Prior medications will be summarized by preferred name using the number and percentage of 
subjects for each treatment group and overall. A subject reporting the same medication more 
than once will be counted only once when calculating the number and percentage of subjects 
who received that medication. The summary will be provided by preferred term in order of 
descending overall frequency. For drugs with the same frequency, sorting will be done 
alphabetically.
For the purposes of analysis, any medication with a start date prior to the first dosing date of 
study drug will be included in the prior medication summary regardless of when the stop date is. 
If a partial start date is entered the medication will be considered prior unless the month and year 
(if day is missing) or year (if day and month are missing) of the start date are after the first 
dosing date. Medications with a completely missing start date will be included in the prior 
medication summary, unless otherwise specified.
Summaries will be based on the Safety Analysis Set. No formal statistical testing is planned.
7.4.2.
Concomitant Medications
Concomitant medications are defined as medications taken while a subject took study drug. Use 
of concomitant medications will be summarized by preferred name using the number and 
percentage of subjects for each treatment group and overall. A subject reporting the same 
medication more than once will be counted only once when calculating the number and 
percentage of subjects who received that medication. The summary will be ordered by preferred 
term in descending overall frequency. For drugs with the same frequency, sorting will be done 
alphabetically.
For the purposes of analysis, any medications with a start date prior to or on the first dosing date 
of study drug and continued to be taken after the first dosing date, or started after the first dosing 
date but prior to or on the last dosing date of study drug will be considered concomitant 
medications. Medications started and stopped on the same day as the first dosing date or the last 
dosing date of study drug will also be considered concomitant. Medications that stopped on the 
same day as the first dosing date will be considered concomitant. Medications with a stop date 
prior to the date of first dosing date of study drug or a start date after the last dosing date of study 
drug will be excluded from the concomitant medication summary. If a partial stop date is 


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entered, any medication with the month and year (if day is missing) or year (if day and month are 
missing) prior to the date of first study drng administration will be excluded from the 
concomitant medication summruy. If a prutial strut date is entered, any medication with the 
month and year (if day is missing) or year (if day and month ru·e missing) after the study dmg 
stop date will be excluded from the concomitant medication smnmruy. Medications with 
completely missing strut and stop dates will be included in the concomitant medication sUIIllnruy , 
unless othe1wise specified. Smnmru·ies will be based on the Safety Analysis Set. No fo1mal 
statistical testing is planned. 
For subjects who entered LTE, concomitant medications with a sta1t date prior to the first dose 
date of any study drng for L TE will be allocated to the Main Study phase. Concomitant 
medications with a strut date on or after first dose date of any study diug for L TE will be 
allocated to the L TE phase. 
For subjects who entered LTE, a concomitant medication with incomplete start date that is prior 
to the month and year ( or year) of the first dose date of any study diug for L TE will be allocated 
to the Main Study phase. A concomitant medication with incomplete strut date that is after the 
month and yeru· ( or yeru') of the first dose date of any study diug for L TE will be allocated to the 
LTEphase. 
In addition, a concomitant medication with completely missing strut date or incomplete strut date 
that is saine as the month and yeru· ( or year) of the first dose date of study diug for L TE, and stop 
date that is prior to the date ( or month and yeru· if day is not recorded; or year alone if month is 
not recorded) of the first dose of study diug for L TE will be allocated to the Main Study phase. A 
concomitant medication with completely missing strut date or incomplete strut date that is same 
as the month and yeru· ( or yeru') of the first dose date of study diug for L TE, and stop date that is 
missing, or the saine as, or after the date ( or month and year if day is not recorded; or year alone 
if month is not recorded) of the first dose of study diug for L TE will be allocated to the L TE 
phase. 
Smnmru·ies will be based on the Safety Analysis Set. No fonnal statistical testing is planned. 
All prior and concomitant medications ( other than per-protocol study mugs) will be provided in a 
by-subject listing so1ted by subject ID number and administration date in chronological order. 
7.5. 
Other Safety Measures 
A data listing will be provided for subjects who become pregnant during the study. 
7.6. 
Changes From Protocol-Specified Safety and Other Analyses 
Safety analyses based on treatment policy estimand will not be perfo1med. 
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8.
REFERENCES
Healy P, Helliwell P. Measuring dactylitis in clinical trials: which is the best instrument to use? 
Journal of Rheumatology 2007;34:1302-6.
Liu JT, Tzeng CS, Tsou HH. Establishing Non-Inferiority of a New Treatment in a Three-Arm 
Trial: Apply a Step-Down Hierarchical Model in a Papulopustular Acne Study 
and an Oral Prophylactic Antibiotics Study. International Journal of Statistics in 
Med Research 2014;3 (1):11-20.
Rubin DB. Multiple Imputation for Nonresponse in Surveys. New York, NY: John Wiley & 
Sons, Inc; 1987. 


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9.
SOFTWARE
SAS® Software Version 9.4. SAS Institute Inc., Cary, NC, USA.
nQuery Advisor(R) Version 4.0. Statistical Solutions, Cork, Ireland.


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10.
SAP REVISION
Revision Date
(DD MMM YYYY)
Section
Summary of Revision
Reason for Revision


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11.
APPENDICES
Appendix 1.
Heath Assessment Questionnaire Disability Index (HAQ-DI)
Appendix 2.
FACIT-Fatigue Scale (Version 4) and Scoring Guidelines
Appendix 3.
Oral Corticosteroids Dose Conversion Chart
Appendix 4.
Sample SAS Code for Analysis of Binary Endpoints
Appendix 5.
Determining Missing and Virtual visits due to COVID-19
Appendix 6.
Lists of PsA Medications


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Appendix 1.
Heath Assessment Questionnaire Disability Index (HAQ-DI)
The HAQ-DI score is defined as the average of the scores of eight functional categories (dressing 
and grooming, arising, eating, walking, hygiene, reach, grip, and other activities), usually 
administered by the subject.  Responses in each functional category are collected as 0 (without 
any difficulty) to 3 (unable to do a task in that area), with or without aids or devices. 
The highest score for questions in each category (range 0 to 3) determines the score for the 
category, unless aids or devices are required. Dependence on equipment or physical assistance 
increases a lower score (ie, scores of 0 or 1) to the level of 2 to more accurately represent 
underlying disability. The eight category scores are averaged into an overall HAQ-DI score on a 
scale from 0 (no disability) to 3 (completely disabled) when 6 or more categories are nonmissing.  
If more than 2 categories are missing, the HAQ-DI score is set to missing.  The HAQ-DI can be 
treated as a continuous measure. 
The HAQ-DI score using aids (and/or devices) is computed by taking the maximum score of the 
questions in each category (range: [0, 3]) and whether or not aids/devices are used (0 or 1):
A = 
max(dressing & grooming category questions, 2*aids indicator) +
max(rising category questions, 2*aids indicator) +
max(eating category questions, 2*aids indicator) +
max(walking category questions, 2*aids indicator) +
max(hygiene category questions, 2*aids indicator) +
max(reach category questions, 2*aids indicator) +
max(grip category questions, 2*aids indicator) +
max(usual activities category questions, 2*aids indicator)
HAQ-DI = A/(total number of categories with at least 6 nonmissing)


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The following table shows the contribution of the 43 questions used to calculate the HAQ-DI:
Category questions:
At least 6 categories must have scores to 
compute the HAQ-DI.
HAQ-DI Category:
Category Questions
Aids/Devices Indicators
HAQ-DI Category Score with 
Aids/Devices Calculation:
Dressing / Grooming
HAQ0101, HAQ0102
(DRESS, HAIR)
HAQ0114, HAQ0119
(DRSG, GROOM)
Arising
HAQ0103, HAQ0104
(STAND, BED)
HAQ0116, HAQ0120
(CHAIR, ARISING)
Eating
HAQ0105,HAQ0106, 
HAQ0107
(MEAT, LIFT,MILK)
HAQ0115, HAQ0121
(UTENSIL, EAT)
Walking
HAQ0108, HAQ0109
(WALK, STEPS)
HAQ0110, HAQ0111, 
HAQ0112, HAQ0113, 
HAQ0122
(CANE, WALKER, 
CRUTCH, WHEEL, 
WALKING)
Hygiene
HAQ0123, HAQ0124, 
HAQ0125
(WASH, BATH, 
TOILET)
HAQ0134, HAQ0135, 
HAQ0137, HAQ0139, 
HAQ0142
(RAISEAT, BATHBAR, 
BATHSEAT, 
LONGBATH, 
HYGIENE)
Reach
HAQ0126, HAQ0127
(REACH, BEND)
HAQ0138, HAQ0143
(LONGRCH, REACH)
Grip
HAQ0128, HAQ0129, 
HAQ0130
(OPENCAR, JAR, 
FAUCET)
HAQ0136, HAQ0144
(JAROPEN, GRIP)
Activity
HAQ0131, HAQ0132, 
HAQ0133
(SHOP, INCAR, 
CHORES)
HAQ0145
(ERRAND)
Using each question with a scale of 
0-3, calculate the category score as 
the maximum of the category 
questions.
If the Aids/Devices indicator is 
“No”, no need to adjust the category 
score.
If the Aids/Devices indicator is 
“Yes” and the category score is <2, 
then the category score with the 
Aids/Devices is set to 2.
If the Aids/Devices indicator is 
“Yes” and the category score is ≥2, 
then the category score with 
Aids/Devices is the calculated 
category score without adjustment.
For example:
The Dressing/Grooming category 
score is 2 if subject answered 1 for 
both questions 1 and 2 and “Yes” for 
both question 14 and 19.
In the HAQ-DI score calculation, 
questions on other device/aids will 
not be used.
Handling Missing Data: If no more than 2 categories have missing category scores, then the 
HAQ-DI is the mean of the nonmissing category scores. Otherwise, the HAQ-DI score is set to 
missing.
If any of the category questions are missing, but the aids/device indicator is nonmissing, the 
category score can still be computed.  However, if all category questions and its aids/device 
indicators are missing, then the category score is considered missing. 


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Appendix 2.
FACIT-Fatigue Scale (Version 4) and Scoring Guidelines
FACIT-Fatigue Scale (Version 4)
Below is a list of statements that other people with your illness have said are important. 
Please circle or mark one number per line to indicate your response as it applies to the past 
7 days.
Not at 
all
A little 
bit
Some-
what
Quite
a bit
Very 
much
HI7
I feel fatigued
0
1
2
3
4
HI12
I feel weak all over
0
1
2
3
4
An1
I feel listless (“washed out”)
0
1
2
3
4
An2
I feel tired
0
1
2
3
4
An3
I have trouble starting things because I am tired
0
1
2
3
4
An4
I have trouble finishing things because I am tired
0
1
2
3
4
An5
I have energy
0
1
2
3
4
An7
I am able to do my usual activities
0
1
2
3
4
An8
I need to sleep during the day
0
1
2
3
4
An12 I am too tired to eat
0
1
2
3
4
An14 I need help doing my usual activities
0
1
2
3
4
An15 I am frustrated by being too tired to do the things 
I want to do
0
1
2
3
4
An16 I have to limit my social activity because I am 
tired
0
1
2
3
4


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FACIT-Fatigue Subscale Scoring Guidelines (Version 4)
Instructions:
5) Record answers in "item response" column. If missing, mark with an X.
6) Perform reversals as indicated, and sum individual items to obtain a score.
7) Multiply the sum of the item scores by the number of items in the subscale, then divide by 
the number of items answered. This produces the subscale score.
8) The higher the score, the better the QOL.
Subscale
Item Code
Reverse Item?
Item Response
Item Score
Fatigue Subscale
HI7
4 -
________
=________
HI12
4 -
________
=________
Score range: 0 – 52
An1
4 -
________
=________
An2
4 -
________
=________
An3
4 -
________
=________
An4
4 -
________
=________
An5
0 +
________
=________
An7
0 +
________
=________
An8
4 -
________
=________
An12
4 -
________
=________
An14
4 -
________
=________
An15
4 -
________
=________
An16
4 -
________
=________
Sum individual item scores:
=________
Multiply by 13:
=________
Divide by number of items answered:
=________
= Fatigue Subscale score


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Appendix 3.
Oral Corticosteroids Dose Conversion Chart
The following table will be used for converting non-prednisone medications to prednisone 
equivalent:
Example: Subject is taking 8 mg of Methylprednisolone orally daily. To get the equivalent dose 
of prednisone: 8 mg Methylprednisolone = (5*8)/4 = 10 mg prednisone. 
Corticosteroids Name
Equivalent Dose (mg) to 5 mg Prednisone
Deflazacort
7.5 mg
Methylprednisolone
4 mg
Prednisolone
5 mg
Prednisone
5 mg
Triamcinolone Acetonide
4 mg


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Appendix 4.
Sample SAS Code for Analysis of Binary Endpoints
The following model statement will be used to construct the confidence interval for the binomial 
proportion difference described in Section 6.3.2:
    proc freq data = test ;
        by avisitn;
        tables TRT01PN*aval_ / riskdiff (CORRECT); 
        output out = f200vp_ci RISKDIFF;
        where TRT01PN = 1 | TRT01PN = 3;
    run;
where the confidence interval for the difference of two independent binomial proportions is 
constructed based on the normal approximation (ie, the Wald method) with a continuity 
correction, to adjust for the difference between the normal approximation and the binomial 
distribution, which is a discrete distribution:
(𝑝1 ― 𝑝2) ± ( 1
2
1
𝑛1 +
1
𝑛2 + 𝑧𝛼/2 ×
𝑝1(1 ― 𝑝1)
𝑛1
+ 𝑝2(1 ― 𝑝2)
𝑛2
)
The following model statement will be used to construct the confidence interval for the binomial 
proportion described in the Section 6.3.2:
    proc freq data = test ;
        by avisitn TRT01PN;
        tables aval_ / BINOMIAL (CORRECT); 
    run;
the confidence interval for the binomial proportions is constructed based on the normal 
approximation to the binomial distribution with continuity correction:
𝑝1 ± ( 1
2
1
𝑛1 + 𝑧
𝛼/2
×
𝑝1(1 ― 𝑝1)
𝑛1
)
==f 
(-)-
V 
. . . .r 
(- -)-
V 
V 


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Appendix 5.
Determining Missing and Virtual visits due to COVID-19
This appendix describes the site collection of COVID-19 data as pertains to missed/virtual visits 
and the data processing algorithm used to determine which visits were missing and which visits 
were virtual.
Data collection
A COVID-19 supplement to the eCRF Completion Guidelines (CCG) was provided by data 
management to instruct clinical trial sites with respect to data entry expectations pertaining to 
scenarios related to the COVID-19 pandemic.  If a visit was missed, sites should enter “Visit 
missed due to COVID-19.”  If a visit was conducted virtually, sites should enter “Virtual visit 
due to COVID-19.”  
Determination of Missed and Virtual visits
Natural Language Processing (NLP) was used to search the CRF comment fields to identify 
instances of “COVID-19” (or synonyms, see Table 11-1) and “Virtual” (or synonyms, 
see Table 11-1).  The search terms are maintained in a global lookup and can be modified to tune 
the NLP model.  For any comments with COVID-19 search terms, assign “Missed visit” or 
“Virtual visit” as follows
i)
If COVID-19 terms are identified through NLP and the visit date is missing then 
result is ‘Missed Visit’
ii) If COVID-19 and Virtual terms are identified through NLP for a visit, then result is 
‘Virtual Visit’. When there are multiple records for the same subject and the same 
visit, NLP will be based on multiple records to ensure 1 unique category per subject 
per visit
iii) Otherwise result is missing
Table 11-1.
Examples of search terms for “COVID-19” and “Virtual” used to 
identify missed and virtual visits.
Search terms for “COVID-19”
Search terms for “Virtual”
COVID19
CORONA
CORONAVIRUS
PANDEMIC
OUTBREAK
CRISIS
LOCKDOWN
QUARANTINE
SHELTER
VIRTUAL
TELEMED
TELEHEALTH
TELEPHONE
REMOTE
TELEMEDICINE
TELECONSULTATION
TELEPHONICALLY
PHONE
HOME VISIT
ZOOM
SKYPE


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Appendix 6.
Lists of PsA Medications
1) List of bioDMARDs and Investigational bDMARDs (WHO Preferred Terms)

ABATACEPT

ADALIMUMAB

ALEFACEPT

BIMEKIZUMAB

BRODALUMAB

CERTOLIZUMAB PEGOL

ETANERCEPT

GOLIMUMAB

GUSELKUMAB

INFLIXIMAB

IXEKIZUMAB

SECUKINUMAB

TOCILIZUMAB

USTEKINUMAB
2) List of csDMARDs (WHO Preferred Terms)

AZATHIOPRINE

CICLOSPORIN

HYDROXYCHLOROQUINE SULFATE

IGURATIMOD

LEFLUNOMIDE

METHOTREXATE

METHOTREXATE SODIUM

SULFASALAZINE


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3) List of Corticosteroids (WHO Preferred Terms)

BETAMETHASONE ACETATE;BETAMETHASONE SODIUM PHOSPHATE

BETAMETHASONE BUTYRATE PROPIONATE;MAXACALCITOL

BETAMETHASONE DIPROPIONATE;BETAMETHASONE SODIUM PHOSPHATE

BETAMETHASONE DIPROPIONATE;CALCIPOTRIOL

CLOBETASOL

CLOBETASOL PROPINOATE

CORTISONE

DEFLAZACORT

METHYLPREDNISOLONE

METHYLPREDNISOLONE ACETATE

METHYLPREDNISOLONE SODIUM SUCCINATE

PREDNISOLONE

PREDNISOLONE VALEROACETATE

PREDNISONE

TRIAMCINOLONE

TRIAMCINOLONE ACETONIDE
4) List of NSAIDs (WHO Preferred Terms)

ACECLOFENAC

CELECOXIB

CODEINE PHOSPHATE;IBUPROFEN

DEXKETOPROFEN TROMETAMOL

DICLOFENAC

DICLOFENAC POTASSIUM


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
DICLOFENAC SODIUM

ESOMEPRAZOLE MAGNESIUM;NAPROXEN

ETODOLAC

ETORICOXIB

IBUPROFEN

KETOPROFEN

LOXOPROFEN SODIUM DIHYDRATE

MELOXICAM

NABUMETONE

NAPROXEN

NAPROXEN SODIUM

NIMESULIDE

SULINDAC

TENOXICAM


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yyyy hh:mm:ss)
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00:37:49
PPD
PPD