A Randomized, Double-blind, Controlled, Multi-center Study to Evaluate the Efficacy and Safety of Dose De-escalation of Orally Administered Filgotinib in Subjects With Ulcerative Colitis in Clinical Remission
Phase: PHASE3
Conditions: Ulcerative Colitis
Sponsor: Galapagos NV

Galapagos 
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CLINICAL STUDY PROTOCOL 
Project Number: 
GLPG0634 
 
 
Study Number: 
GLPG0634-CL-341 
 
 
Study Title 
A randomized, double-blind, controlled, multi-center study to evaluate the 
efficacy and safety of dose de-escalation of orally administered filgotinib in 
subjects with ulcerative colitis in clinical remission 
Short Study Title 
A study evaluating the effect of filgotinib dose de-escalation in patients 
with ulcerative colitis in remission  
Development 
Phase: 
3b 
Status 
Final 
 
 
Protocol Version: 
2.0 
Date: 
17-Mar-2023 
Amendment: 
1  
EudraCT No: 
2022-000719-30 
CT.gov No: 
NCT05479058 
IND No: 
129647 
Sponsor: 
Galapagos NV, Generaal De Wittelaan L11 A3, 2800 Mechelen, Belgium 
Medical Leader: 
 
General CSP 
 
 
 
 
Confidentiality Statement 
The information contained in this document is privileged and confidential. It is the property of Galapagos NV and 
may not be used, disclosed, reproduced or otherwise disseminated within your organization or communicated to any 
third parties without the express written authorization of Galapagos NV. 

Galapagos 
 
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EMERGENCY CONTACT INFORMATION 
In case of a serious adverse event (SAE) (if it is not possible to record SAE information 
electronically), a special situation (see Section 11.1.6) or in case of pregnancy during the clinical 
study, the investigator must report this immediately, and under no circumstances later than 
24 hours following the knowledge of the event as follows: 
E-mail: 
 
or 
 Medical Safety SAE Fax #:
 
 
 
In case of medical questions during the course of the study, the investigator must contact the 
contract research organization (CRO) medical monitor or, if unavailable, his/her back-up (contact 
details are provided separately): 
The following number is available for urgent medical contact: 
24-Hour Answering Service for Urgent Medical Issues: 
 Medical Monitoring Support Center (MMSC) 
Phone: 
 
Fax: 
 
 
 
Sponsor back-up contact number1: 
 
 
 
 
                                                 
1 This is the number of a contact center, which will refer the requester to the appropriate sponsor contact for the 
study. 

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TABLE OF CONTENTS 
EMERGENCY CONTACT INFORMATION ........................................................................... 2 
TABLE OF CONTENTS ........................................................................................................ 3 
CLINICAL STUDY PROTOCOL HISTORY ............................................................................ 8 
SUMMARY OF CHANGES ................................................................................................... 9 
LIST OF TABLES .................................................................................................................15 
LIST OF FIGURES ...............................................................................................................15 
LIST OF APPENDICES ........................................................................................................15 
LIST OF ABBREVIATIONS AND DEFINITION OF TERMS..................................................16 
1. 
CLINICAL STUDY PROTOCOL SYNOPSIS .................................................................21 
2. 
INTRODUCTION ...........................................................................................................28 
2.1. 
Clinical Study Rationale .....................................................................................28 
2.2. 
Background - Nonclinical Studies .......................................................................29 
2.3. 
Background - Clinical Studies ............................................................................29 
3. 
CLINICAL STUDY OBJECTIVES ..................................................................................29 
3.1. 
Primary Objective...............................................................................................29 
3.2. 
Secondary Objective(s) ......................................................................................29 
. 
 .....................................................................................30 
4. 
ENDPOINTS AND ESTIMANDS ...................................................................................30 
4.1. 
Primary Endpoint/Estimand ................................................................................30 
4.2. 
Secondary Endpoints .........................................................................................31 
 
 ........................................................................................32 
5. 
INVESTIGATIONAL PLAN ............................................................................................32 
5.1. 
Clinical Study Design .........................................................................................32 
5.2. 
Clinical Study Design Rationale .........................................................................35 
5.3. 
Dosing Rationale ...............................................................................................36 
5.4. 
Treatment Discontinuation, Subject Withdrawal .................................................36 
5.4.1. 
Treatment Discontinuation ..................................................................36 
5.4.1.1. 
Permanent Treatment Discontinuation ...............................37 
5.4.1.2. 
Temporary Treatment Discontinuation ...............................38 
5.4.1.3. 
Disease Worsening Criteria ...............................................39 
5.4.2. 
Subject Withdrawal .............................................................................40 
5.4.3. 
Lost to Follow-up ................................................................................40 
5.5. 
Potential Risks and Benefits ..............................................................................40 
Potential Benefits ...............................................................................................40 
Potential Risks ...................................................................................................40 

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Risk Mitigation ...................................................................................................42 
6. 
CLINICAL STUDY POPULATION .................................................................................43 
6.1. 
Inclusion Criteria ................................................................................................43 
6.2. 
Exclusion Criteria ...............................................................................................44 
6.3. 
Prohibition and Restrictions ...............................................................................45 
6.3.1. 
Precautions for Sexual Intercourse .....................................................45 
6.3.1.1. 
Female Subjects ................................................................45 
6.3.1.1.1. 
Definition of Childbearing Potential ................45 
6.3.1.1.2. 
Contraceptive Methods ..................................46 
6.3.1.2. 
Male Subjects ....................................................................46 
6.3.1.3. 
Unacceptable Birth Control Methods .................................47 
6.3.1.4. 
Procedures to be Followed in the Event of Pregnancy .......47 
6.3.2. 
Prior and Concomitant Medications ....................................................47 
6.3.2.1. 
Allowed Medications ..........................................................47 
6.3.2.2. 
Prohibited Medications ......................................................47 
6.3.3. 
Food and Beverage Restrictions .........................................................48 
6.4. 
Measures to Minimize Bias ................................................................................48 
6.4.1. 
Randomization ....................................................................................48 
6.4.2. 
Blinding and Unblinding ......................................................................48 
7. 
INVESTIGATIONAL PRODUCT ....................................................................................49 
7.1. 
Identity of the Investigational Product ................................................................49 
7.2. 
Dosage and Administration ................................................................................50 
7.3. 
Packaging, Labeling, and Distribution ................................................................51 
7.4. 
Storage ..............................................................................................................52 
7.5. 
Treatment Compliance and Drug Accountability ................................................52 
8. 
CLINICAL STUDY ASSESSMENTS ..............................................................................52 
8.1. 
Timing of Assessments ......................................................................................52 
8.1.1. 
Order of Assessments ........................................................................53 
8.1.2. 
End of Treatment Visit ........................................................................54 
8.1.3. 
Re-screening of Subjects ....................................................................54 
8.1.4. 
Unblinding of Subjects at the Study Primary Analysis Time Point .......54 
8.2. 
Unscheduled Visits ............................................................................................54 
8.3. 
Efficacy Assessments ........................................................................................55 
8.3.1. 
Endoscopy and Biopsy Sample Collection ..........................................55 
8.3.2. 
Mayo Clinical Score ............................................................................55 
 
................................................................................56 
. 
y ...................................56 
. 
 
 
 ....................................................................56 
. 
 ........................................................56 
. 
 .................................................................................56 
8.4. 
Safety Assessments ..........................................................................................56 
8.4.1. 
Adverse Events ...................................................................................57 
8.4.2. 
Clinical Laboratory Evaluations ...........................................................57 
8.4.3. 
Physical Examination ..........................................................................57 
8.4.4. 
Vital Signs ...........................................................................................57 
8.4.5. 
12-lead Electrocardiogram ..................................................................58 

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. 
 ..........................................................................58 
 
...................................................................................58 
 
 ............................................................................59 
 
 ......................59 
 
............................59 
8.7. 
Sample Management .........................................................................................59 
8.7.1. 
Total Blood Volume .............................................................................59 
8.7.2. 
Blood and Urine Samples for Routine Safety Tests.............................60 
 
....................60 
8.8. 
Optional Long-term Storage of Samples and Associated Data for Future 
Clinical and Research Assessments ..................................................................60 
8.9. 
Schedule of Activities .........................................................................................62 
8.9.1. 
Regular Schedule of Activities ............................................................62 
8.9.2. 
Schedule of Activities After Re-escalation ...........................................67 
9. 
STATISTICAL METHODS .............................................................................................69 
9.1. 
Determination of Sample Size ............................................................................69 
9.2. 
Population for Analyses .....................................................................................71 
9.2.1. 
All Screened Subjects .........................................................................71 
9.2.2. 
All Randomized Subjects ....................................................................71 
9.2.3. 
Full Analysis Set .................................................................................71 
9.2.4. 
Safety Analysis Set .............................................................................72 
 
 .............................................................72 
9.3. 
Statistical Analyses ............................................................................................72 
9.3.1. 
General Statistical Considerations ......................................................72 
9.3.2. 
Interim Analysis ..................................................................................72 
9.3.3. 
Analyses of Demographics and Baseline Characteristics ....................72 
9.3.4. 
Analyses of Efficacy Parameters .........................................................73 
9.3.4.1. 
Analysis for Primary Efficacy Endpoint...............................73 
9.3.4.1.1. 
Primary Efficacy Estimand .............................73 
9.3.4.1.2. 
Secondary Efficacy Estimand ........................74 
9.3.4.2. 
Analyses for Secondary Efficacy Endpoints .......................75 
9.3.4.2.1. 
Analyses for Continuous Efficacy Data ..........75 
9.3.4.2.2. 
Analyses for Time-to-Event Data ...................80 
 
 ...............................80 
9.3.5. 
Analyses of Safety Data ......................................................................81 
9.3.5.1. 
Extent of Exposure ............................................................81 
9.3.5.2. 
Adverse Events .................................................................81 
9.3.5.3. 
Clinical Laboratory Evaluations ..........................................81 
9.3.5.4. 
Vital Signs .........................................................................82 
9.3.5.5. 
12-lead Electrocardiogram .................................................82 
 
 ..................................................................82 
 
 ...................................................82 
 
..........................................................82 
9.3.9. 
Subgroups ..........................................................................................83 
9.3.10. 
Additional Statistical Considerations ...................................................83 
10. DATA MONITORING .....................................................................................................83 
10.1. 
Data Monitoring Committee ...............................................................................83 
10.1.1. 
Cardiovascular Safety Endpoint Adjudication Committee ....................83 

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11. SAFETY REPORTING ..................................................................................................84 
11.1. 
Definitions of Adverse Events, Serious Adverse Events, and Special 
Situations ...........................................................................................................84 
11.1.1. 
Adverse Events ...................................................................................84 
11.1.2. 
Serious Adverse Events ......................................................................84 
11.1.3. 
Unlisted (Unexpected) Adverse Events/ Reference Safety 
Information ..........................................................................................84 
11.1.4. 
Adverse Events of Special Interest (Immediately Reportable to the 
Sponsor) .............................................................................................84 
11.1.5. 
Clinical Laboratory Abnormalities and Other Abnormal 
Assessments as Adverse Events or Serious Adverse Events .............85 
11.1.6. 
Special Situations ...............................................................................85 
11.2. 
Assessment of Adverse Events and Serious Adverse Events ............................86 
11.2.1. 
Assessment of Causality .....................................................................86 
11.2.2. 
Assessment of Severity ......................................................................87 
11.3. 
Instructions for Reporting Adverse Events, Serious Adverse Events, 
Pregnancies, and Other Special Situations ........................................................88 
11.3.1. 
Adverse Events ...................................................................................88 
11.3.2. 
Serious Adverse Events ......................................................................88 
11.3.3. 
Pregnancy ..........................................................................................89 
11.3.4. 
Reporting of Special Situations (Other Than Pregnancy) With or 
Without Associated Adverse Events ...................................................89 
11.4. 
Sponsor Reporting Requirements ......................................................................90 
12. SPONSOR’S AND INVESTIGATOR’S RESPONSIBILITIES .........................................90 
12.1. 
Sponsor’s Responsibilities .................................................................................90 
12.1.1. 
Regulatory Authority Approval ............................................................90 
12.1.2. 
Clinical Study Closure Considerations ................................................90 
12.1.3. 
Indemnification ....................................................................................91 
12.1.4. 
Insurance ............................................................................................91 
12.1.5. 
Archiving .............................................................................................91 
12.2. 
Reporting ...........................................................................................................92 
12.3. 
Publication .........................................................................................................92 
12.4. 
Investigator’s Responsibilities ............................................................................92 
12.4.1. 
Financial Disclosure ............................................................................92 
12.4.2. 
Source Data and Data Capture ...........................................................93 
12.4.3. 
Archiving .............................................................................................93 
12.4.4. 
Participation Cards ..............................................................................93 
12.5. 
Confidentiality ....................................................................................................93 
12.6. 
Protection of Personal Data ...............................................................................94 
12.7. 
Ethical Considerations .......................................................................................96 
12.7.1. 
Independent Ethics Committee / Institutional Review Board ...............96 
12.7.2. 
Informed Consent ...............................................................................96 
12.8. 
Data Quality Control/Assurance .........................................................................97 
12.8.1. 
Monitoring ...........................................................................................97 
12.8.2. 
Audit and Inspection ...........................................................................97 
13. REFERENCES ..............................................................................................................98 
14. APPENDICES ...............................................................................................................99 

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SIGNATURE PAGE – SPONSOR ...................................................................................... 103 
SIGNATURE PAGE – INVESTIGATOR ............................................................................. 104 
 
 

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CLINICAL STUDY PROTOCOL HISTORY 
Clinical Study Protocol 
(CSP)/Amendment # 
Date 
Main Rationale 
General/Country-Specific 
CSP Version 1.0 
04-Apr-2022 
Initial CSP Version 
General  
CSP Version 2.0 / Amendment 1 
17-Mar-2023 
The risk of venous thromboembolism has 
been added to the protocol to align with 
the Investigator’s Brochure (IB) 
Edition 17, 15-Jul-2022. 
Study drug interruption criteria for 
lymphopenia, neutropenia, and moderate 
renal impairment were added, information 
about possible effects on spermatogenesis 
was updated, and contraceptive 
requirements for male subjects and 
reporting of pregnancies in their female 
partners were removed to align with the IB 
Edition 17, 15-Jul-2022. 
Clarifications from the Protocol 
Clarification Note dated 11-Jul-2022, 
regarding ulcerative colitis flare and 
biopsies, were incorporated. 
Clarifications were added regarding 
corticosteroids, food intake, End of 
Treatment visit, unblinding of subjects at 
the study primary analysis endpoint, and 
hepatitis B virus (HBV) surveillance.  
The eligibility criteria and screening 
assessments were updated, re-screening 
allowed, and the screening period was 
extended.  
The definitions of women of childbearing 
potential and postmenopausal female were 
changed. 
General 
 
 

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SUMMARY OF CHANGES 
Amendment 1 (17-Mar-2023) 
The overall reasons for this amendment: 
a 
The risk of venous thromboembolism has been added to the benefit/risk section to align with the potential 
risks in the Investigator’s Brochure (IB) Edition 17, 15-Jul-2022 and the specific discontinuation criterion 
in this clinical study protocol (CSP). 
b 
To add a study drug interruption criterion regarding lymphopenia, neutropenia, and moderate renal 
impairment to align with the IB Edition 17, 15-Jul-2022. 
c 
To update the information on possible effects on spermatogenesis to align with the IB Edition 17, 
15-Jul-2022. 
d 
To remove contraceptive requirements for male subjects and reporting of pregnancies in their female 
partners during this study to align with the IB Edition 17, 15-Jul-2022. 
e 
To change the definitions of childbearing potential and postmenopausal female; follicle stimulating 
hormone (FSH) test at screening was added to confirm postmenopausal status if applicable. 
f 
To clarify when an endoscopy (i.e. sigmoidoscopy) should be conducted to align with the Schedule of 
Activities, and to clarify that 2 biopsies should be collected during each sigmoidoscopy, including any 
non-scheduled endoscopy performed when a subject experiences flare. 
g 
To extend the screening period to 28 days to allow the investigator time to complete all required 
assessments, and to introduce re-screening of subjects after screening failure to increase the chance for 
subjects to participate in this study. 
h 
To add fecal calprotectin (FCP) as a screening test if the last observation was >6 months prior to 
screening or the most recent FCP value was >250 µg/g, to increase the chance for subjects to participate 
in this study. 
i 
To clarify the tuberculosis (TB) assessments at screening. 
j 
To clarify hepatitis B virus (HBV) eligibility requirements and surveillance during the study.  
k 
To clarify that orally- and/or rectally-administered corticosteroids may be used during flare, but 
intravenous corticosteroids are not permitted during the study. 
l 
To clarify that the investigational product (IP) may be taken both with and without food. 
m To clarify that in countries where filgotinib becomes commercially available, the Week 48 visit can 
replace or occur on the same day as the End of Treatment (EoT) visit. 
n 
To clarify unblinding of subjects at the study primary analysis time point and to add an unscheduled visit 
for IP dispensing, to ensure all subjects have sufficient IP to cover the period until the next 24-weekly 
visit. 
In addition, minor updates and administrative corrections were made. 
The changes made to the CSP GLPG0634-CL-341 (CAPYBARA) Version 1.0, 4-April-2022, are listed 
below, reflecting a brief rationale of each change and the applicable sections. 

Galapagos 
 
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Change and Rationale: The risk of venous thromboembolism has been added to the benefit/risk section to 
align with the potential risks in the IB Edition 17, 15-Jul-2022 and the specific discontinuation criterion in this 
CSP. 
Applicable section: 
5.5  Potential Risks and Benefits 
Change and Rationale: A study drug interruption criterion for subjects with an absolute lymphocyte count 
<500 cells/mm3 was added.  
The requirement to permanently discontinue a subject after 2 sequential neutrophil counts 
<750 neutrophils/mm3 was removed and replaced with a study drug interruption criterion for absolute 
neutrophil counts <1000 neutrophils/mm3.   
A study drug interruption criterion for confirmed moderate renal impairment was added.  
These changes were made to align with the IB Edition 17, 15-Jul-2022.  
Applicable Section: 
5.4.1 Treatment Discontinuation 
Change and Rationale: The information on possible effects on spermatogenesis was updated to align with 
the IB Edition 17, 15-Jul-2022. Based on the results from the clinical testicular safety studies, Galapagos NV 
has proposed to remove the potential risk of impaired spermatogenesis. 
Applicable Section: 
5.5 Potential Risks and Benefits 
Change and Rationale: The requirements for male subjects to use contraception and for pregnancies in their 
female partners to be reported during this study were removed in alignment with the IB Edition 17, 15-Jul-
2022. The use of male contraception is not mentioned in the IB, as possible seminal transfer is not considered 
to lead to relevant systemic exposure in partners of childbearing potential. 
Applicable Sections: 
Protocol Synopsis 
6.1 Inclusion Criteria 
6.2 Exclusion Criteria 
6.3.1.2 (section deleted) Male Subjects 
6.3.1.4 Procedures to be Followed in the Event of Pregnancy 
11.3.3 Pregnancy 
12.7.2 Informed Consent 

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Change and Rationale: The definition of childbearing potential and postmenopausal female was changed to 
align with the sponsor’s current standards, which are aligned with the Clinical Trials Facilitation Group’s 
“Recommendations related to contraception and pregnancy testing in clinical trials”.  
Assessment of follicle stimulating hormone (FSH) was added as a laboratory test at screening to confirm  
postmenopausal status in female subjects who may have become postmenopausal during the parent study.  
The contraception requirements for females were modified to remove the requirement for the use of a barrier 
method with hormonal contraceptives because in the dedicated clinical pharmacology study there was no 
effect on the pharmacokinetics of the combined oral contraceptive ethinyl estradiol and levonorgestrel when 
coadministered with filgotinib.  
Applicable Sections: 
6.3.1.1.1 Definition of Childbearing Potential 
6.3.1.1.2 Contraceptive Methods (females) 
8.9 Schedule of Activities 
Appendix 3: Clinical Laboratory Assessments 
Change and Rationale: It was clarified that 2 biopsies should be collected during each sigmoidoscopy, and 
that these biopsies should be carried out at Week 48 and every 48 weeks thereafter, and also at the time of 
suspected ulcerative colitis (UC) flare.  
Applicable Sections: 
5.1 Clinical Study Design 
8.3.1 Endoscopy and Biopsy Sample Collection 
8.9.1 Regular Schedule of Activities 
Change and Rationale: The screening period was extended to 28 days to allow the investigator time to 
complete all required assessments, and re-screening of subjects after screening failure was introduced to 
increase the chance for subjects to be able to participate in this study.  
Applicable Sections: 
Protocol Synopsis 
5.1 Clinical Study Design 
8.1 Timing of Assessments  
8.1.3 (new section) Re-screening of Subjects 
8.9.1 Regular Schedule of Activities 
Change and Rationale: Fecal calprotectin (FCP) was added as a screening test if the last observation was 
>6 months prior to screening or the most recent value was >250 µg/g, to increase the chance for subjects to be 
able to participate in this study. 
Applicable Sections: 
Protocol Synopsis 
5.1 Clinical Study Design 
6.1 Inclusion Criteria 
8.1 Timing of Assessments 
8.9.1 Regular Schedule of Activities 

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Change and Rationale: Subjects who had a positive QuantiFERON® test or 2 indeterminate 
QuantiFERON® TB test results during any of the visits of the SELECTION-LTE but do not have active or 
latent tuberculosis (TB) at the time of screening, or had latent TB and underwent adequate treatment and 
continued in the SELECTION-LTE, and subjects who were previously treated for TB with a complete and 
adequate course of therapy as per local standard of care and as verified by the investigator, and do not need to 
have yearly QuantiFERON® tests, should be screened for signs and symptoms consistent with reactivation of 
TB and do not need to perform QuantiFERON® at the time of screening. 
Exclusion criterion 8 was modified to include screening for signs and symptoms of TB reactivation for 
subjects not requiring QuantiFERON® test. 
Applicable Section: 
Protocol Synopsis 
6.2 Exclusion criteria 
8.1 Timing of Activities 
8.9.1 Regular Schedule of Activities 
Change and Rationale: Exclusion criterion 9 for subjects with a history of malignancy was aligned with the 
eligibility of the parent UC studies by adding the specification that it applies to the last 5 years prior to or 
during participation in the UC parent studies. 
Applicable Sections: 
Protocol Synopsis 
6.2 Exclusion criteria 
Change and Rationale: Subjects with positive hepatitis B virus core antibodies (HBcAb) and hepatitis B 
virus (HBV) DNA below the lower limit of quantification (LLOQ) in a parent UC study require ongoing 
HBV DNA monitoring every 12 weeks during this study. These subjects may also require prophylactic 
treatment per investigator discretion in accordance with local guidelines and standard of care. Any subject 
who has HBV DNA ≥LLOQ will be discontinued. 
Applicable Section: 
5.5. Potential Risks and Benefits  
8.9.1 Regular Schedule of Activities 
Change and Rationale: It was clarified that orally- and/or rectally-administered corticosteroids may be used 
during flare and should not exceed prednisone 30 mg/day equivalents (except for at least 12 weeks prior to 
screening and including baseline of the present study) and that intravenous corticosteroids are not permitted 
during the study. 
Applicable Sections: 
5.1 Clinical Study Designs 
6.3.2.1 Allowed Medications 
6.3.2.2 Prohibited Medications 
Change and Rationale: It was clarified that the IP may be taken both with and without food. 
Applicable Section: 
6.3.3 Food and Beverage Restrictions 
7.2 Dosage and Administration 

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Change and Rationale: It was clarified that in countries where filgotinib becomes commercially available, 
the Week 48 visit can replace or occur on the same day as the EoT visit. 
Applicable Section: 
Protocol Synopsis 
5.1 Clinical Study Design 
8.1.2 (new section) End of Treatment visit 
8.9.1 Regular Schedule of Activities 
Change and Rationale: It was clarified that all subjects should be invited for an unblinding visit no later than 
4 weeks after study primary endpoint unblinding. If no regular visit is scheduled within this time frame, an 
unscheduled visit should be performed for IP dispensing to ensure the subject has sufficient IP to cover the 
period until the next 24-weekly visit. 
Applicable Sections: 
Protocol Synopsis 
5.1 Clinical Study Design 
8.1.4 (new section) Unblinding of subjects at the primary analysis time point 
Change and Rationale: It was clarified that the secondary estimand for the primary endpoint would estimate 
the effect of decreasing the filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 200 mg q.d. 
regardless of permanent treatment discontinuation as well as flare, or temporary treatment interruptions, in 
subjects who are in stable clinical remission at study entry. 
Applicable Sections: 
Protocol Synopsis 
9.3.4.1.2 Secondary Efficacy Estimand 
9.3.4.2.1 Analyses for Continuous Efficacy Data 
Change and Rationale: The end of study definition for a country was modified because some subjects may 
not switch to commercially available filgotinib, but instead to local standard of care. 
Applicable Sections: 
Definition of terms 
Protocol Synopsis 
5.1 Clinical Study Design 
Change and Rationale: To align with the risk mitigation in Section 5.5, diagnosis of malignancy (except 
successfully treated non-melanoma skin cancer or cervical carcinoma in situ) was added to the conditions for 
permanent discontinuation of study treatment.  
Applicable Sections: 
5.4.1.1 Permanent Treatment Discontinuation 
5.5 Potential Risks and Benefits 

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Change and Rationale: The Schedule of Activities after re-escalation was corrected to add vital signs, weight 
and urine pregnancy test assessments. 
Applicable Sections: 
8.9.2 Schedule of Activities After Re-escalation 
 
 

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LIST OF TABLES 
Table 1: 
Prohibited Medications .....................................................................................48 
Table 2: 
Causal Attribution Guidance .............................................................................87 
Table 3: 
Grading of AE Severity .....................................................................................87 
 
LIST OF FIGURES 
Figure 1: 
Schematic Diagram ..........................................................................................35 
Figure 2: 
Worst-case Precision for a Range of Sample Sizes Using Newcombe 
Continuity-corrected CIs With 50% Remission Rate in at Least 1 Group ..........70 
Figure 3: 
Precision for a Sample Size of 40 Subjects per Group Using Newcombe 
Continuity-corrected CIs ...................................................................................71 
 
LIST OF APPENDICES 
 ...................................................................................99 
Appendix 2: Mayo Scoring System for Assessment of Ulcerative Colitis Activity ................ 100 
Appendix 3: Clinical Laboratory Assessments .................................................................... 101 
Appendix 4: Management of Clinical and Laboratory Adverse Events ................................ 102 
 

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LIST OF ABBREVIATIONS AND DEFINITION OF TERMS 
Abbreviations 
ADL 
Activities of Daily Living 
AE 
adverse event 
ALT 
alanine aminotransferase 
ANCOVA 
analysis of covariance 
AST 
aspartate aminotransferase 
 
 
CES 
carboxylesterase 
CI 
confidence interval 
 
 
CrCl 
creatinine clearance 
CRF 
case report form 
CRO 
contract research organization 
CRP 
C-reactive protein 
CSP 
clinical study protocol 
CTCAE 
Common Terminology Criteria for Adverse Events 
CVEAC 
Cardiovascular Safety Endpoint Adjudication Committee 
DVT 
deep venous thrombosis 
EBS 
endoscopy/bleeding/stool 
ECG 
electrocardiogram 
ED 
early discontinuation 
e-Diary 
electronic diary  
EoS 
End of Study 
EoT 
End of Treatment 
 
 
ES 
endoscopic score 
EU 
European Union 
FAS 
full analysis set 
FCP 
fecal calprotectin 
GCP 
Good Clinical Practice 
HBV 
hepatitis B virus 
HCV 
hepatitis C virus 
HDL 
high-density lipoprotein  

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IB 
investigator’s brochure 
IBDQ 
Inflammatory Bowel Disease Questionnaire 
ICF 
informed consent form 
ICH 
International Council for Harmonisation of Technical Requirements 
for Pharmaceuticals for Human Use 
IEC 
Independent Ethics Committee 
IL 
interleukin 
INR 
international normalized ratio 
IP 
investigational product 
IRB 
Institutional Review Board 
JAK 
Janus Kinase 
LDL 
low-density lipoprotein 
LLOQ 
lower limit of quantitation 
LOCF 
last observation carried forward 
LTE 
long-term extension 
MCS 
Mayo Clinical Score 
mMCS 
modified Mayo Clinical Score 
PE 
pulmonary embolism 
PEG 
polyethylene glycol 
PGA 
Physician’s Global Assessment 
 
 
pMCS 
partial Mayo Clinical Score 
PRO2 
patient-reported outcome based on 2 items 
PT 
prothrombin time 
PTM 
placebo-to-match 
PTT 
partial thromboplastin time 
Q1 
first quartile 
Q3 
third quartile 
q.d. 
once daily (quaque die) 
RBC 
red blood cell 
RTSM 
randomization and trial supply management 
SAE 
serious adverse event 
SAP 
statistical analysis plan 
SARS-CoV-2 
severe acute respiratory syndrome coronavirus 2 
SD 
standard deviation 

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SE 
standard error 
 
 
SI 
international system of units 
SOC 
System Organ Class 
SUSAR 
suspected unexpected serious adverse reaction 
TB 
tuberculosis 
TEAE 
treatment-emergent adverse event 
 
 
TMF 
trial master file 
TNF 
tumor necrosis factor 
UC 
ulcerative colitis 
UK 
United Kingdom 
ULN 
upper limit of normal 
US 
United States 
WBC 
white blood cell 
WOCBP 
women of childbearing potential 
 
 
 
 
 

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Definition of Terms  
 
baseline assessment 
last available assessment prior to the first intake of investigational 
product (IP) in the present study  
clinical study 
a clinical study as described in this protocol refers to a clinical trial in 
which subjects are assigned to treatment with an IP to discover or 
verify its clinical efficacy, safety, pharmacological, or other 
pharmacodynamic effects  
Cockroft-Gault 
formula 
estimate of creatinine clearance (CrCl) using serum creatinine level: 
CrCl (male) = ([140-age] × weight in kg)/(serum creatinine × 72) 
CrCl (female) = CrCl (male) × 0.85 
end of the study in a 
particular country 
the end of the study may differ between the countries and depends on 
the commercial availability of filgotinib in that country: 
− 
in countries where filgotinib becomes commercially available: 
date when the last subject in that country has completed the safety 
follow-up visit 
− 
in countries where filgotinib is not commercially available: date 
when the last subject in that country completes 216 weeks in the 
study 
global end of the 
study 
date of the last visit for the last subject in the last country (i.e. last 
subject last visit) 
endoscopic score 
(ES)-confirmed 
ulcerative colitis 
(UC) flare 
a flare defined as an increase in rectal bleeding subscore by at least 
1 point AND an increase in stool frequency subscore by at least 
2 points AND an increase in endoscopic subscore by at least 1 point 
 
 
 
 
  
  
  
  
  
  
  
Mayo Clinical Score 
(MCS) 
composed of subscores from endoscopic findings, rectal bleeding, 
stool frequency, and Physician’s Global Assessment (PGA) 
modified Mayo 
Clinical Score 
(mMCS) 
composed of subscores from rectal bleeding, stool frequency, and 
endoscopic findings 

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mMCS remission  
mMCS score ≤2, with endoscopic subscore of ≤1, stool frequency 
subscore of ≤1, and a rectal bleeding subscore of 0 
 
 
 
 
 
 
 
 
 
 
 
PRO2 flare 
a flare defined as a PRO2 (patient-reported outcome based on 2 items) 
score worsening of at least 2 points and an absolute PRO2 score of at 
least 3, with stool frequency subscore ≥2, and rectal bleeding subscore 
≥1 
re-escalation 
the term re-escalation is used to describe the switch to open-label 
200 mg filgotinib once daily (q.d.) after ES-confirmed UC flare 
regardless of the blinded treatment received before the switch, i.e. from 
blinded 100 mg q.d. to open-label 200 mg q.d. (real re-escalation) or 
from blinded 200 mg to open-label 200 mg q.d. (dummy re-escalation) 
stable pMCS clinical 
remission 
defined as pMCS remission on at least 2 consecutive quarterly visits in 
the SELECTION-LTE study prior to screening of the present study 
study start  
date when the first informed consent form is signed (i.e. first subject 
first visit) 
 

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1. 
CLINICAL STUDY PROTOCOL SYNOPSIS 
Title of Study 
A randomized, double-blind, controlled, multi-center study to evaluate the efficacy and safety 
of dose de-escalation of orally administered filgotinib in subjects with ulcerative colitis in 
clinical remission 
Short Title of Study 
A study evaluating the effect of filgotinib dose de-escalation in patients with ulcerative colitis 
in remission  
Phase of Development: Phase 3b 
Objectives and Endpoints 
Objectives 
Endpoints 
Primary  
To evaluate the efficacy of filgotinib in 
subjects in stable clinical remission on 
200 mg filgotinib once daily (q.d.) for whom 
the dose was decreased to 100 mg q.d. 
compared to subjects remaining on 200 mg 
q.d. 
− Proportion of subjects in corticosteroid-free1 clinical 
remission based on modified Mayo Clinical Score 
(mMCS)2 at Week 48. 
 
Secondary 
To evaluate the effect of dose de-escalation 
of filgotinib on time to flare. 
− Time to PRO2 flare3. 
− Time to endoscopic score (ES)-confirmed ulcerative 
colitis (UC) flare. 
To evaluate the effect of dose de-escalation 
of filgotinib on disease-specific biomarkers 
and Inflammatory Bowel Disease 
Questionnaire (IBDQ). 
− Change from baseline in C-reactive protein (CRP) and 
fecal calprotectin (FCP) up to Week 48. 
− Change from baseline in IBDQ at Week 48. 
To evaluate the safety and tolerability of 
filgotinib. 
− Frequency and severity of treatment-emergent adverse 
events (TEAEs), treatment-emergent serious AEs 
(SAEs), and TEAEs leading to treatment 
discontinuation. 
Planned Number of Subjects 
Approximately 80 subjects are planned to be randomized. 
                                                 
1 Free of corticosteroids for at least 12 weeks. 
2 mMCS of ≤2 points, with endoscopic subscore of ≤1, stool frequency subscore of ≤1, and a rectal bleeding 
subscore of 0. 
3 Defined as a PRO2 (patient-reported outcome based on 2 items) score worsening of at least 2 points and an 
absolute PRO2 score of at least 3, with stool frequency subscore ≥2 and rectal bleeding subscore ≥1. 

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Study Design 
This study is a Phase 3b, randomized, double-blind, controlled, multi-center study to evaluate 
the efficacy and safety of dose de-escalation of orally administered filgotinib in subjects with 
UC in corticosteroid-free clinical remission. 
Approximately 80 subjects, who are in clinical remission on 200 mg filgotinib q.d. for at least 
2 consecutive quarterly visits in the ongoing SELECTION-LTE study (GLPG0634-CL-307), 
are planned to be rolled over and randomized (1:1) to receive either 100 mg or 200 mg 
filgotinib q.d. Subjects will be stratified according to ES (0 or 1) at baseline to ensure 
treatment balance in each stratum. The study will consist of the following study periods: 
− 
screening period: maximum of 28 days with at least 2 screening visits; 
− 
treatment period:  
• 
During the blinded treatment period, study visits will be on Day 1 (randomization to 
blinded treatment), at Week 4, Week 12, and then every 12 weeks. Subjects will 
receive blinded treatment until the primary analysis time point (i.e. after the last 
subject completed their Week 48 postbaseline visit or has completed their Week 12 
post re-escalation visit, or after the last follow-up of subjects discontinuing prior to 
Week 48, whichever comes last), with the exception of subjects with ES-confirmed 
UC flare who will be switched to open-label 200 mg filgotinib q.d. (as explained 
below).  
• 
After unblinding at the study primary analysis time point, subjects will receive 
unblinded treatment and the frequency of study visits will be reduced to every 
24 weeks, as detailed in the protocol.  
− 
follow-up: 4 weeks after last dose (End of Study [EoS] visit). 
Subjects who experience an ES-confirmed UC flare during treatment will be “re-escalated”1 to 
open-label 200 mg filgotinib q.d. for at least 12 weeks, while maintaining the blind for the 
treatment at randomization. An ES-confirmed UC flare should be reported as an adverse event. 
In case of further worsening of symptoms after Week 2 following re-escalation and/or no 
improvement in partial Mayo Clinical Score (pMCS) is detected at Week 4, addition of 
corticosteroid treatment (i.e. orally- and/or rectally-administered corticosteroids) can be 
considered with a maximum dose of 30 mg q.d. prednisone equivalent.  
If the subject does not respond to re-escalation therapy within a timeframe of maximum 
12 weeks, the subject will be permanently discontinued from the treatment and invited to 
remain in the study up to Week 48.  
If subject improvement is sufficient in the opinion of the investigator, the subject may continue 
on open-label 200 mg filgotinib q.d. until the end of the study. 
After unblinding at the study primary analysis time point, subjects will receive unblinded 
treatment q.d. until the end of the study. 
A schematic diagram of clinical study design, procedures, and stages is provided below. 

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EoT: End of Treatment; EoS: End of Study; ES: endoscopic score; mMCS: modified Mayo Clinical Score; 
n: number of subjects in the treatment group; q.d.: once daily. 
a mMCS of ≤2 points, with endoscopic subscore of ≤1, stool frequency subscore of ≤1, and rectal bleeding 
subscore of 0. 
b EoS: when the last subject has completed the safety follow-up visit in that country (i.e. after completing 
minimum 48 weeks of treatment and the safety follow-up visit) OR (in countries where filgotinib is not 
commercially available) when the last subject completes 216 weeks in the study. 
Study Duration 
Each subject will be in the study for a minimum of approximately 56 weeks (screening period 
28 days + 48 weeks of treatment + 4 weeks follow-up) in countries where filgotinib will 
become commercially available, and for a maximum duration of 216 weeks (approximately 
4 years) in case filgotinib will not become commercially available. In case of re-escalation, the 
subject will remain in the study at least until the next regular scheduled visit after the 12 weeks 
post re-escalation visit, or until the end of the study in that country, whichever is longer. 
In countries where filgotinib becomes commercially available, the study will be terminated for 
the subjects who have already completed at least 48 weeks of treatment. Subjects will then be 
requested to attend the End of Treatment (EoT) visit as soon as possible. For the subjects who 
have not yet completed the Week 48 visit when filgotinib becomes commercially available, the 
Week 48 visit can replace or occur on the same day as the EoT visit. When the EoT visit is 
performed, the subjects will be considered as having completed the treatment part of the study 
and can start taking commercial filgotinib or local standard of care the next day. In addition, 
subjects will be requested to attend a follow-up visit 4 weeks after the EoT visit. The study will 
be terminated in that country when the last subject in that country has completed the safety 
follow-up visit. 
                                                 
1 The term re-escalation is used to describe the switch to open-label 200 mg filgotinib q.d. after ES-confirmed UC 
flare regardless of the blinded treatment received before the switch, i.e. from blinded 100 mg q.d. to open-label 
200 mg q.d. (real re-escalation) or from blinded 200 mg to open-label 200 mg q.d. (dummy re-escalation). 

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Main Criteria for Inclusion and Exclusion 
Main Inclusion Criteria 
− 
Criterion modified per amendment 1. 
Subjects must be participating in the SELECTION-LTE study, currently on 200 mg 
filgotinib q.d. and fulfill the following conditions: 
• 
pMCS remission1 over a period of at least 2 consecutive quarterly visits in the 
SELECTION-LTE study prior to screening of the present study; 
• 
free of corticosteroids for at least 12 weeks prior to and including baseline; 
• 
FCP <=250 µg/g at last observation within 6 months prior to screening or 
FCP <=250 µg/g during the screening of the present study. 
• 
sigmoidoscopy ES of 0 or 1 (local score) at screening. 
 
− 
Willing to refrain from live attenuated vaccines during the study and for 12 weeks after 
the last dose of filgotinib in the study. 
− 
Female subjects of childbearing potential must have a negative highly sensitive (serum 
beta human chorionic gonadotropin) pregnancy test during screening and must agree to 
continued monthly urine dipstick pregnancy testing during filgotinib treatment 
− 
Criterion modified per amendment 1.  
Female subjects of childbearing potential must agree to use highly effective contraception 
measures as defined in the protocol.  
Main Exclusion Criteria 
− 
Any chronic medical condition (including but not limited to, cardiac or pulmonary disease, 
alcohol, or drug abuse) that, in the opinion of the investigator or sponsor, would make the 
subject unsuitable for the study or would prevent compliance with the study protocol. 
− 
Subject has a known hypersensitivity to filgotinib ingredients or history of a significant 
allergic reaction to filgotinib ingredients as determined by the investigator. 
− 
Female subject who is pregnant or breastfeeding, or intending to become pregnant or 
breastfeed, and/or plans to undergo egg donation or egg harvesting for the purpose of 
current or future fertilization, during the study and until the end of the study. 
− 
Subject is unable or unwilling to comply with restrictions regarding prior and concomitant 
medication as described in the protocol.Criterion modified per amendment 1.  
Subject has a positive QuantiFERON® tuberculosis (TB) test at screening or has 
2 indeterminate QuantiFERON® TB test results that require IP treatment interruption, or 
subject has sign and symptoms of TB reactivation at screening. 
− 
Criterion modified per amendment 1.  
History of malignancy during or in the last 5 years prior to participation in the UC parent 
studies, except for subjects who have been successfully treated for nonmelanoma skin 
cancer or cervical carcinoma in situ.  
− 
Subject meets discontinuation criteria of the SELECTION-LTE study. 
                                                 
1pMCS of ≤2 points, with Physician’s Global Assessment (PGA) ≤1, stool frequency subscore ≤1,and rectal bleeding 
subscore = 0. 

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Treatment and Treatment Schedule 
Subjects will be randomized to receive either 100 mg or 200 mg filgotinib q.d.  
In case of ES-confirmed UC flare during treatment, subjects will be re-escalated to open-label 
200 mg filgotinib q.d. for at least 12 weeks, while maintaining the blind for the treatment at 
randomization. If the subject does not respond to re-escalation therapy within a timeframe of 
maximum 12 weeks, the subject will be permanently discontinued from the treatment. If 
subject improvement is sufficient in the opinion of the investigator, the subject may continue 
on open-label 200 mg filgotinib q.d. until the end of the study. 
Investigational Product, Dosage, and Mode of Administration 
Filgotinib is available as 200 mg and 100 mg strength tablets. Filgotinib tablets, 200 mg and 
100 mg are beige, debossed with “GSI” on one side and “200” or “100” on the other, 
capsule-shaped, biconvex, film-coated tablets for clinical use. Each tablet contains the 
equivalent of 200 mg or 100 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. 
Placebo-to-match (PTM) 200 mg and 100 mg filgotinib tablets are identical in appearance to 
the respective active filgotinib tablets. PTM 200 mg and 100 mg 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. 
The IP needs to be taken q.d. at approximately the same time. Subjects will be asked to 
swallow the IP with a glass of water. 
Blinded treatment up to the primary analysis time point 
Doses of 100 mg or 200 mg filgotinib, as a combination of 2 tablets (filgotinib and PTM) for 
blinding purposes, will be taken q.d. orally. 
Subjects will be provided with medication kits containing 2 bottles with blinded IP, either: 
− 
100 mg filgotinib tablets in bottle 1 and PTM 200 mg filgotinib tablets in bottle 2; 
− 
200 mg filgotinib tablets in bottle 1 and PTM 100 mg filgotinib tablets in bottle 2. 
If on Day 1, the subject has already taken the IP as assigned in the SELECTION-LTE study, 
the first dose as assigned in this study should be taken on Day 2. Starting from Day 2, subjects 
will be instructed to take 1 tablet from each bottle q.d. (i.e. a total of 2 tablets). 

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Re-escalation 
Subjects who are re-escalated to open-label 200 mg filgotinib q.d. will be provided with bottles 
containing unblinded IP (200 mg filgotinib tablets in 1 bottle). If the subject has already taken 
IP on the re-escalation baseline day, the first adjusted dose should be taken on re-escalation 
Day 2. Subjects will be instructed to take 1 tablet q.d. 
After unblinding at the primary analysis time point 
For continued q.d. treatment after unblinding until the end of the study, subjects will be 
provided with unblinded IP, either: 
− 
1 bottle with 100 mg filgotinib tablets; 
− 
1 bottle with 200 mg filgotinib tablets. 
Subjects will be instructed to take 1 tablet q.d. 
Statistical Analysis 
Interim analysis  
The data collected from this study will be analyzed at 2 time points. An unblinded interim 
analysis of the clinical study data will be performed by the sponsor on cleaned and locked data, 
when the last subject completed their Week 48 postbaseline visit or has completed their 
Week 12 post re-escalation visit (if baseline of re-escalation is within the first 48 weeks of the 
study), or after the last follow-up of subjects discontinuing prior to Week 48, whichever comes 
last. This analysis will be the primary analysis. The analyses will be conducted on efficacy 
data up to Week 48 and safety data up to the data cut-off date, to be able to evaluate the 
primary, secondary, and exploratory efficacy endpoints, and safety. The subjects and the 
clinical study team will be unblinded at the time of the Week 48 analysis. 
The final analysis will be performed after the global end of the study (i.e. date of the last visit 
for the last subject in the last country) and the database is cleaned and locked. At the final 
analysis, all available efficacy and safety data will be summarized using descriptive statistics.  
Efficacy analysis 
No hypothesis testing will be performed. The de-escalation effect will be described using 
standard descriptive statistics, but also with model-based estimates for the differences with 
95% confidence intervals (CIs) as appropriate. 
Primary endpoint 
The primary efficacy estimand for the primary endpoint targets to estimate the effect of 
decreasing the filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 200 mg 
q.d. on corticosteroid-free mMCS remission without ES-confirmed flare or discontinuation of 
treatment at Week 48, regardless of treatment interruptions, in subjects who are in stable 
clinical remission at study entry. The effect size will be estimated using the Mantel-Hanszel 
method and expressed as a difference in proportions. 

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The secondary estimand for the primary endpoint targets to estimate the effect of decreasing 
the filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 200 mg q.d. on 
corticosteroid-free mMCS remission at Week 48, regardless of flare, permanent treatment 
discontinuation, or temporary treatment interruptions, in subjects who are in stable clinical 
remission at study entry. The effect size will be estimated using the Mantel-Hanszel method 
and expressed as a difference in proportions. 
Secondary endpoints 
Estimands for the secondary efficacy endpoints are described in the protocol. 
Safety analysis 
Safety data will be summarized descriptively by treatment group according to the filgotinib 
dosing regimen actually received at randomization. 
For the primary safety analysis, any data collected after ES-confirmed UC flare will not be 
included in the analyses.  
For the secondary safety analysis, data will be included regardless of flare.  
Additionally, safety data may be analyzed in the subgroup of subjects who are initially 
assigned to 100 mg filgotinib q.d. and are re-escalated later to 200 mg q.d. in the safety 
analysis set.  

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2. 
INTRODUCTION 
2.1. 
Clinical Study Rationale 
Ulcerative colitis (UC) is a chronic, idiopathic, inflammatory disease that affects the colon and is 
most prevalent in adults between the ages of 30 and 40 years. It is characterized by relapsing and 
remitting mucosal inflammation extending from the rectum to the proximal segments of the 
colon. 
The etiology of the disease is believed to involve immune, genetic, environmental, and microbial 
factors. Discoordinated activity of both the innate and adaptive immune response in combination 
with defects of the epithelial barrier and dysbiosis lead to an inflammatory cascade resulting in 
bloody diarrhea, rectal urgency and tenesmus, and in its later stages an increased risk for 
colorectal cancer. Further UC extraintestinal symptoms include ocular lesions, skin lesions, 
arthritis, and primary cholangitis. 
Historically, UC has been managed with anti-inflammatory drugs and general 
immunosupressants. In the last 2 decades, approaches have become more targeted using biologics 
acting on tumor necrosis factor (TNF) alpha, and more recently anti-integrin and anti-interleukin 
(IL)-12/IL-23 antibodies. 
However, while biologics have provided substantial improvements in patient therapy, about 30% 
of patients do not respond to biologics and a further 30 to 50% will stop responding during 
therapy. 
A new approach to UC therapy involves orally bioavailable small-molecules inhibiting signal 
transduction pathways involved in UC pathogenesis, such as Janus Kinase (JAK) inhibitors. 
Filgotinib is a preferential JAK1 inhibitor approved for the treatment of rheumatoid arthritis and 
UC in the European Union (EU), United Kingdom (UK), and Japan. 
While clinical data indicate that response to 200 mg filgotinib once daily (q.d.) is more rapid and 
pronounced compared to 100 mg filgotinib q.d. in subjects with moderate to severely active UC, 
maintenance of clinical remission may be achieved at a lower dose. 
This study will explore the possibility of dosing flexibility in subjects who are in clinical 
remission on 200 mg filgotinib q.d. in the SELECTION-LTE (GLPG0634-CL-307) study. 
For more details refer to the latest version of the investigator’s brochure (IB) and its relevant 
updates/addenda. 
This clinical study will be conducted in compliance with this clinical study protocol (CSP), the 
current International Council for Harmonisation of Technical Requirements for Pharmaceuticals 
for Human Use – Good Clinical Practice (ICH-GCP) Guideline E6, and applicable local ethical 
and legal requirements (see also Section 12). 

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2.2. 
Background - Nonclinical Studies 
For nonclinical pharmacology, PK, and toxicology data of filgotinib, refer to the IB (Section 1, 
Company Core Data Sheet). 
2.3. 
Background - Clinical Studies 
The efficacy and safety of 200 mg and 100 mg filgotinib q.d. in 1351 subjects with moderately to 
severely active UC were evaluated in a randomized, double-blind, placebo-controlled combined 
Phase 2b/3 study over a duration of 58 weeks (SELECTION, GS-US-418-3898). The study 
combined 2 consecutive substudies: an induction study assessing subject response at Week 10 
and a maintenance study continuing until Week 58. Subjects who achieved either 
endoscopy/bleeding/stool (EBS) remission or Mayo Clinical Score (MCS) response at Week 10 
of the induction study were re-randomized into the maintenance study. 
A significant number of subjects receiving 200 mg filgotinib q.d. achieved clinical remission at 
the end of the induction study compared to placebo. At Week 58 and the end of the maintenance 
study, significance was achieved by both the 200 mg q.d. and the 100 mg q.d. cohort. 
A long-term extension (LTE) study (SELECTION-LTE, GS-US-418-3899, GLPG0634-CL-307) 
is ongoing in 1161 subjects who have completed the SELECTION study. Subjects who did not 
achieve EBS remission or MCS response as well as subjects who met the prespecified definition 
of disease worsening during the SELECTION study were given the option to receive open-label 
200 mg filgotinib in the SELECTION-LTE study. 
Filgotinib 100 mg and 200 mg q.d. were generally well tolerated in both studies. In an integrated 
safety analysis based on results of the SELECTION study and interim results of the 
SELECTION-LTE study, including 1253 subjects, no significant differences between treatment 
groups in occurrence of adverse events (Aes), serious Aes (SAEs), or Aes leading to study 
discontinuation could be found. Rates of serious infections, herpes zoster, opportunistic 
infections, venous thrombosis, pulmonary embolism, malignancies, and gastrointestinal 
perforation were low and comparable across treatment groups. Overall, 3 deaths were reported; 
none of the Aes leading to death were assessed as related to filgotinib. 
3. 
CLINICAL STUDY OBJECTIVES 
3.1. 
Primary Objective 
− 
To evaluate the efficacy of filgotinib in subjects in stable clinical remission on 200 mg 
filgotinib q.d. for whom the dose was decreased to 100 mg q.d. compared to subjects 
remaining on 200 mg q.d. 
3.2. 
Secondary Objective(s) 
− 
To evaluate the effect of dose de-escalation of filgotinib on time to flare. 
− 
To evaluate the effect of dose de-escalation of filgotinib on disease-specific biomarkers and 
Inflammatory Bowel Disease Questionnaire (IBDQ). 

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The primary estimand for the primary endpoint is described according to the following attributes: 
Primary Endpoint 
Primary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 200 mg 
q.d. defined through the appropriate inclusion / exclusion criteria. 
Variable 
Binary corticosteroid-free mMCS remission without ES-confirmed 
flare and without discontinuation of treatment at Week 48. 
Corticosteriod-free is defined as free of corticosteroids for at least 
12 weeks. 
Intercurrent events 
including strategy for 
addressing them 
− 
ES-confirmed UC flare: Subjects randomized to the filgotinib 
100 mg q.d. or 200 mg q.d. group will be considered as 
nonresponders for any visit after the re-escalation visit, for 
flares occurring prior to Week 48 (Composite strategy). 
− 
Permanent treatment discontinuation (not flare-related): 
Subjects who discontinue treatment prior to Week 48 will be 
considered as nonresponders in both the 100 mg q.d. and the 
200 mg q.d. group (Composite strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be included 
as reported in the analysis (Treatment policy strategy). 
Population-level 
summary 
The treatment difference in the percentage of subjects meeting 
corticosteroid-free mMCS remission criteria between the filgotinib 
100 mg q.d. group and 200 mg q.d. group at Week 48. 
Estimator 
The adjusted proportion difference (filgotinib 200 mg – filgotinib 
100 mg) with corresponding 95% confidence interval (CI) as 
calculated by a stratified Mantel-Haenszel test (stratification factor: 
baseline ES [0 or 1]). 
 
Refer to Section 9.3.4.1 for more information. 
4.2. 
Secondary Endpoints  
− 
Time to PRO2 flare1. 
− 
Time to ES-confirmed UC flare. 
− 
Change from baseline in C-reactive protein (CRP) and fecal calprotectin (FCP) up to 
Week 48. 
− 
Change from baseline in IBDQ at Week 48. 
                                                 
1 Defined as a PRO2 (patient-reported outcome based on 2 items) score worsening of at least 2 points and an 
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− 
Frequency and severity of treatment-emergent adverse events (TEAEs), treatment-emergent 
SAEs, and TEAEs leading to treatment discontinuation. 
 
Refer to Section 9.3.4.2 for more information. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5. 
INVESTIGATIONAL PLAN 
5.1. 
Clinical Study Design 
This study is a Phase 3b, randomized, double-blind, controlled, multi-center study to evaluate the 
efficacy and safety of dose de-escalation of orally administered filgotinib in subjects with UC in 
corticosteroid-free clinical remission. 
Approximately 80 subjects, who are in clinical remission on 200 mg filgotinib q.d. for at least 
2 consecutive quarterly visits in the ongoing SELECTION-LTE study, are planned to be rolled 
over and randomized (1:1) to receive either 100 mg or 200 mg filgotinib q.d. Subjects will be 
stratified according to ES (0 or 1) at baseline to ensure treatment balance in each stratum.  
                                                 
 
 
 
 
 
 

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The study will consist of the following study periods: 
− 
screening period: a maximum of 28 days with at least 2 screening visits; 
− 
treatment period:  
• 
During the blinded treatment period, study visits will be on Day 1 (randomization to 
blinded treatment), at Week 4, Week 12, and then every 12 weeks. Subjects will receive 
blinded treatment until the primary analysis time point (i.e. after the last subject 
completed their Week 48 postbaseline visit or has completed their Week 12 post re-
escalation visit, or after the last follow-up of subjects discontinuing prior to Week 48, 
whichever comes last, see Section 6.4.2), with the exception of subjects with ES-
confirmed UC flare who will be switched to open-label 200 mg q.d. (as explained 
below). 
• 
After unblinding at the study primary analysis time point, subjects will receive 
unblinded treatment and the frequency of study visits will be reduced to every 24 weeks 
(see Section 8.1.4).  
− 
follow-up: 4 weeks after last dose (End of Study [EoS]) visit). 
Sigmoidoscopy 
The ES will be obtained from a sigmoidoscopy performed during screening, including collection 
of 2 biopsies for histology assessment. 
Roll-over from SELECTION-LTE 
Subjects in the SELECTION-LTE study who are in clinical remission with 200 mg filgotinib q.d. 
for at least 2 consecutive quarterly visits, will be provided the option to roll-over to the present 
study at any scheduled visit of the SELECTION-LTE study or at a separate visit.  
Subjects will be requested to attend the site for at least 2 screening visits. Depending on the 
results of  FCP (if applicable) and ES at screening, the subject will either be a screening failure 
(FCP >250 µg/g or ES >1) in the present study and will remain in SELECTION-LTE, or the 
subject will be eligible (FCP ≤250 µg/g and ES ≤1) and will need to perform the End of 
Treatment (EoT) assessments in SELECTION-LTE before being randomized to the present 
study. Subjects who fail screening in the present study may be re-screened once. Re-screening 
may only be conducted after approval from the sponsor’s medical lead (see Section 8.1.3). 
Further details on the timing of screening and Day 1 assessments are provided in Section 8.1. 
Flare 
When a subject experiences an increase in clinical symptoms, a stool sample will be obtained for 
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An endoscopy will be performed in subjects who experience during treatment an increase in 
clinical symptoms defined as: 
− 
an increase in rectal bleeding subscore by at least 1 point, AND an increase in stool 
frequency subscore by at least 2 points, AND a Clostridium difficile infection is excluded. 
An ES-confirmed UC flare is defined as: 
− 
an increase in rectal bleeding subscore by at least 1 point AND an increase in stool frequency 
subscore by at least 2 points AND an increase in endoscopic subscore by at least 1 point. 
Subjects who experience an ES-confirmed UC flare during treatment will be “re-escalated” (see 
Definition of Terms) to open-label 200 mg filgotinib q.d. for at least 12 weeks, while maintaining 
the blind for the treatment at randomization, and should follow the Schedule of Activities after 
re-escalation (Section 8.9.2). An ES-confirmed UC flare should be reported as an adverse event 
(AE), as explained in Section 8.4.1. 
Re-escalation 
Subjects should follow the Schedule of Activities after re-escalation (Section 8.9.2). 
− 
In case of further worsening of symptoms after Week 2 following re-escalation and/or no 
improvement in pMCS is detected at Week 4, addition of corticosteroid treatment (i.e. orally- 
and/or rectally-administered corticosteroids) can be considered with a maximum oral dose of 
30 mg q.d. prednisone equivalent. 
− 
If the subject does not respond to re-escalation therapy within a timeframe of maximum 
12 weeks, the subject will be permanently discontinued from the treatment and invited to 
remain in the study up to Week 48 (see Section 5.4.1.1). 
− 
If subject improvement is sufficient in the opinion of the investigator, the subject will restart 
the regular Schedule of Activities (Section 8.9.1), starting from the next 12-weekly visit 
assessments. The subject may continue on open-label 200 mg filgotinib q.d. until the end of 
the study. Corticosteroid treatment should be tapered off at the discretion of the investigator. 
In case symptoms are worsening again after 12 weeks of re-escalation, the disease worsening 
criteria must be applied, as explained in Section 5.4.1.3. 
Study duration 
Each subject will be in the study for a minimum of approximately 56 weeks (28 days screening 
period + 48 weeks of treatment + 4 weeks follow-up) in countries where filgotinib will become 
commercially available, and for a maximum duration of 216 weeks (approximately 4 years) in 
case filgotinib will not become commercially available. In case of re-escalation, the subject will 
remain in the study at least until the next regular scheduled visit after the 12 weeks post 
re-escalation visit, or until the end of the study in that country, whichever is longer. 
In countries where filgotinib becomes commercially available, the study will be terminated for 
the subjects who have already completed at least 48 weeks of treatment. Subjects will then be 
requested to attend the EoT visit as soon as possible. For the subjects who have not yet completed 

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the Week 48 visit when filgotinib becomes commercially available, the Week 48 visit can replace 
or occur on the same day as the EoT visit (see Section 8.1.2). When the EoT visit is performed, 
the subjects will be considered as having completed the treatment part of the study and can start 
taking commercial filgotinib or local standard of care the next day. In addition, subjects will be 
requested to attend a follow-up visit 4 weeks after the EoT visit. The study will be terminated in 
that country when the last subject in that country has completed the safety follow-up visit. 
Reduction in study visits 
After unblinding at the study primary analysis time point, the frequency of study visits will be 
reduced to every 24 weeks (see Section 8.1.4). All subjects should be invited for an unblinding 
visit no later than 4 weeks after the study primary endpoint unblinding. If no regular visit is 
scheduled within this time frame, an unscheduled visit should be performed for IP dispensing to 
ensure the subject has sufficient IP to cover the period until the next 24-weekly visit.  
Subjects who discontinue the study will be asked to attend an early discontinuation (ED) visit. 
A schematic diagram of clinical study design, procedures, and stages is provided in Figure 1. 
 
Figure 1: 
Schematic Diagram 
EoT: End of Treatment; EoS: End of Study; ES: endoscopic score; mMCS: modified Mayo Clinical Score; 
n: number of subjects in the treatment group; q.d.: once daily. 
a mMCS of ≤2 points, with endoscopic subscore of ≤1, stool frequency subscore of ≤1, and rectal bleeding subscore 
of 0. 
b EoS: when the last subject has completed the safety follow-up visit in that country (i.e. after completing minimum 
48 weeks of treatment and the follow-up visit) OR (in countries where filgotinib is not commercially available) when 
the last subject completes 216 weeks in the study. 
5.2. 
Clinical Study Design Rationale 
The study is designed to evaluate the efficacy and safety of dose de-escalation of orally 
administered filgotinib in subjects with UC in clinical remission. 

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Subjects must have been in clinical remission for at least 2 consecutive quarterly visits in the 
SELECTION-LTE study prior to and including screening of the present study, to ensure that 
subjects are stable and that possible effects on efficacy can be attributed to dose change. Since 
UC is a progressive disease and worsening symptoms and flares can occur due to external factors 
as well as natural disease progression, a control group that remains on 200 mg filgotinib q.d. is 
included in the study design. The selected population will be recruited from subjects currently in 
the SELECTION-LTE study.  
While the main objective of the study evaluates the possibility to maintain clinical remission 
while lowering the dose, subjects who do experience a flare will re-escalate to 200 mg filgotinib 
q.d. to evaluate if and how rapidly a response can be re-established. 
Filgotinib is now approved for the treatment of UC in the EU, UK, and Japan, and shows a 
positive benefit-risk profile in patients with UC. To reduce the subject’s burden in terms of both 
travel and site attendance, and assessments required, a reduction of on-site visit frequency will be 
introduced. After study unblinding at the primary analysis time point (see Section 6.4.2), the 
frequency of study visits will be reduced to every 24 weeks. In terms of safety data collection, 
prompt reporting and follow-up of any potential intermittent safety event is emphasized and 
continued on an ongoing basis. 
The maximum study duration for a single subject in the present study is 216 weeks 
(approximately 4 years). This maximum duration is calculated based on the last subject enrolled 
and still included in the SELECTION-LTE study. Since subjects are recruited from 
SELECTION-LTE, they will be provided the opportunity to have the same length of treatment as 
in SELECTION-LTE. 
 
 
 Patients with an active disease state will have elevated IL-6 plasma 
concentrations reported to decrease activity of carboxylesterase (CES)2 (Li et al., 2021; Shen et 
al., 2019), the enzyme involved in the metabolism of filgotinib into the active metabolite. 
 
 
 
 
 
 
5.3. 
Dosing Rationale 
Doses have been selected based on efficacy and safety data in the preceeding SELECTION and 
SELECTION-LTE studies. 
5.4. 
Treatment Discontinuation, Subject Withdrawal 
5.4.1. 
Treatment Discontinuation 
The investigator, who may consult the medical monitor, can consider stopping the study 
treatment in case of concerns about the subject’s safety, serious or severe AEs or worsening of 

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the disease condition, which in the investigator’s opinion needs an alternative treatment approach 
not being covered in the clinical study. Every effort should be made to keep subjects in the study 
and on treatment, taking into account the subject’s safety and well-being. 
5.4.1.1. 
Permanent Treatment Discontinuation 
Treatment with IP must be discontinued by the investigator (who may consult the medical 
monitor) for any of the following conditions: 
a. 
any opportunistic infection, defined at the discretion of the investigator; 
b. any serious infection that requires antimicrobial therapy or hospitalization, or any infection 
that meets SAE reporting criteria; 
c. 
febrile neutropenia (temperature>38.3 °C or a sustained temperature of 38 °C for more than 
1 hour) with absolute neutrophil count of <1000/mm3; 
d. symptomatic anemia (e.g. signs/symptoms including pallor, shortness of breath, new heart 
murmur, palpitations, lethargy, fatigue) with hemoglobin <7.5 g/dL, or if transfusion is 
indicated regardless of hemoglobin value; 
e. 
complicated herpes zoster infection (with multi-dermatomal, disseminated, opthalmic, or 
central nervous system involvement); 
f. 
evidence of active hepatitis C virus (HCV) during the study, as evidenced by HCV RNA 
positivity; 
g. evidence of active hepatitis B virus (HBV) during the study, as evidenced by HBV DNA 
positivity; 
h. any thromboembolic event that meets SAE reporting criteria; 
i. 
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 to be in the 
subjects’s best interest; 
j. 
subject’s request to discontinue for any reason; 
k. subject’s noncompliance; 
l. 
pregnancy; 
m. subject’s use of prohibited concurrent therapy; 
n. laboratory criteria: After becoming aware of any of the below described abnormal laboratory 
changes occurring at any one time, an unscheduled visit (i.e. sequential visit) should occur to 
retest within 3 to 7 days (except creatinine, which should be retested 7 to 14 days apart). 
• 
2 sequential platelet counts <75000 platelets/mm3 (SI <75.0x109 cells/L); 
• 
2 sequential aspartate aminotransferase (AST) or alanine aminotransferase (ALT) 
>3 times the upper limit of normal range (ULN) and at least 1 of the following 
confirmed values: 
• total bilirubin >2x ULN; 
• or international normalized ratio (INR) >1.5; 
• or accompanied by symptoms consistent with hepatic injury. 
For any subject with an initial AST or ALT elevation >3x ULN, at the time of the second 
confirmatory blood draw, INR, prothrombin time (PT) and partial thromboplastin time 
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• 
2 sequential AST or ALT elevations >5x ULN; 
• 
2 sequential values for estimated creatinine clearance (CrCl) <35 mL/min based on the 
Cockcroft-Gault formula1. 
o. disease worsening (refer to Section 5.4.1.3); 
p. nonreponse to re-escalation therapy (refer to Section 5.1). 
q. subjects diagnosed with malignancy during the study except successfully treated non-
melanoma skin cancer or cervical carcinoma in situ.  
Any subject who discontinues study treatment, regardless of reason, will be invited to remain in 
the study and complete the visits as scheduled up to Week 48. 
When the subject is discontinued from the study, the subject will be requested to return for the 
ED visit. 
5.4.1.2. 
Temporary Treatment Discontinuation 
Where possible, IP should not be interrupted. In case IP interruption is needed as per the 
discretion of the investigator (e.g. for intercurrent illnesses, new infections, or elective or 
emergency surgeries), the medical monitor should be consulted prior to IP interruption when 
medically feasible. 
IP interruption should be considered in the following circumstances: 
− 
Subjects with newly positive (converted) or 2 indeterminate QuantiFERON® tuberculosis 
(TB) test (or centrally reported equivalent assay) result(s) should interrupt study drug dosing 
and be evaluated for active TB and latent TB by the investigator per local standard of care. 
An indeterminate result should be repeated once and the second result (if positive or 
negative) will be accepted. Positive or negative results must not be repeated.  
• 
Subjects diagnosed with latent TB (i.e. a subject who has newly identified positive 
diagnostic TB test result, in which active TB has been ruled out) may initiate an 
adequate course of prophylaxis as per local standard of care. Appropriate, ongoing, 
prophylactic treatment for latent TB must be initiated for a minimum of 4 weeks prior to 
the continuation of study medication. Subjects may resume study drug after 
investigator’s consultation with medical monitor.  
• 
Subjects with positive or 2 indeterminate QuantiFERON® test result(s) who are 
determined as having neither latent nor active TB infection may continue participation in 
the study after consultation and approval from the medical monitor.  
• 
Any subject with active TB must be discontinued from the study.  
• 
Subjects who were previously treated for TB with a complete and adequate course of 
therapy as per local standard of care and as verified by the investigator do not need to 
have yearly QuantiFERON® tests. Subjects previously treated for TB should be 
                                                 
1 Estimate of CrCl using serum creatinine level: CrCl (male) = ([140-age] × weight in kg)/(serum creatinine × 72); 
CrCl (female) = CrCl (male) × 0.85. 

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screened at least yearly for signs and symptoms consistent with reactivation of TB and 
any subject with active TB should be discontinued from the study. 
− 
For subjects with absolute lymphocyte count  less than 500 cells/mm3, confirmed via retest 
within 3 to 7 days, filgotinib should be interrupted until grade returns to ≤Grade 2 (more than 
500 cells/mm3). If absolute lymphocyte count does not return to ≤Grade 2 within 4 weeks or 
returns to less than 500 cells/mm3 following re-challenge with IP, then IPshould be 
permanently discontinued and the subject managed according to local practice. 
− 
For subjects with absolute neutrophil counts <1000 cells/mm3 (international system of units 
[SI]: <1.0 x 109 cells/L); an unscheduled visit should occur to retest within a reasonable 
timeframe after establishing, treating, and resolving any possible underlying condition 
(within 3-7 days). The IP should be interrupted until the retest result is available. If the 
abnormal neutrophil count has been confirmed by a retest, the IP will be interrupted until the 
value returns to ≥1000 cells/mm3 (SI: ≥1.0 x 109 cells/L). If the neutrophil abnormality does 
not return to >=1000 cells/mm3 within 4 weeks or recurs following a re-challenge with IP 
and is considered related to IP, then IP should be permanently discontinued and the subject 
should be managed according to local clinical practice. 
− 
After a confirmed laboratory change representing moderate renal impairment (estimated 
CrCl ≥35 mL/min and <60 mL/min per Cockcroft-Gault formula) at any time during the 
study, the following actions should be taken by the investigator and documented: 
• 
Establish possible underlying condition and initiate appropriate action to resolve. 
• 
Retest CrCl within 8 weeks. 
• 
Carefully consider individual benefit/risk of continuation of filgotinib in relation to the 
observation.  If continuation of filgotinib is not considered appropriate, interrupt 
treatment until retest confirms CrCl ≥60 mL/min. The investigator/designee should 
assess individual subject benefit/risk with regards to re-initiation of treatment after 
repeat or prolonged interruptions, or if re-initiation is not considered appropriate. 
Prior to resumption of IP, the investigator should discuss the case with the medical monitor. 
5.4.1.3. 
Disease Worsening Criteria 
When a subject becomes symptomatic, including worsening or return of disease activity, a stool 
sample will be obtained for culture for pathogenic bacteria, ova and parasite evaluation, and 
Clostridium difficile toxin assay. 
Subjects who have been re-escalated after an ES-confirmed UC flare (Section 5.1) and who meet 
the following criteria will be permanently discontinued from study drug treatment and, if 
applicable, will be invited to remain in the study up to Week 48: 
− 
Any subject with significant disease worsening or lack of response to therapy based on 
investigator judgment should discontinue study drug treatment. 
− 
If a subject experiences significant worsening of underlying UC, which requires any of the 
prohibited medications (refer to Section 6.3.2.2), or surgical intervention at any point during 
the study, treatment should be discontinued.  

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5.4.2. 
Subject Withdrawal 
Subjects will be informed prior to clinical study entry that they are allowed to withdraw from the 
clinical study. At any time and for any reason, a subject’s participation in the clinical study may 
terminate at his/her request, without prejudice to their future medical care. The subject will be 
encouraged to share the reason(s) for withdrawal so this can be documented in the source 
documents, and to complete the assessments of the ED visit, but will not be obliged to do so. 
A subject may be withdrawn from the clinical study at any time without the subject’s consent If 
the investigator or sponsor determines that it is not in the best interest of the subject to continue 
participation. In such case, the reason for withdrawal will be documented in the source 
documents, and the subject will be asked to complete the assessments of the ED visit. 
5.4.3. 
Lost to Follow-up 
A subject will be considered lost to follow-up if he or she repeatedly fails to return for scheduled 
visits and is unable to be contacted by the site. The site must make every effort to contact the 
subject to assess and document their health status in the source documents, including checking 
the medical records and contacting general practitioner or relatives, if necessary. 
The following actions must be taken if a subject fails to return to the clinic for a required study 
visit: 
− 
The site must attempt to contact the subject and reschedule the missed visit as soon as 
possible and counsel the subject on the importance of maintaining the assigned visit schedule 
and ascertain whether or not the subject wishes to and/or should continue in the study. 
− 
Before a subject is deemed lost to follow-up, the investigator or designee must make every 
effort to regain contact with the subject (where possible, 3 telephone calls and, if necessary, a 
letter to the subject’s last known mailing address or local equivalent methods). These contact 
attempts should be documented in the subject’s medical record. 
5.5. 
Potential Risks and Benefits 
Potential Benefits 
Filgotinib 200 mg q.d. has shown a rapid and pronounced efficacy response in subjects with 
moderate to severe UC in both the SELECTION and SELECTION-LTE study. 
Patients may benefit from a decrease in filgotinib dose if they can maintain remission (see 
below). 
Potential Risks 
− 
Serious infections: 
JAK inhibition is expected to increase the risk of infection based on the mechanism of 
action. Serious and opportunistic infections, and herpes zoster have been reported for 
participants in clinical studies receiving filgotinib and are considered Important Identified 

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Risks with filgotinib. Adult patients receiving immunomodulatory treatment without any 
evidence of immunity to varicella, may be at increased risk of primary varicella (chicken 
pox) infection should they contract the virus. Reactivation of varicella zoster virus latent 
infection causes herpes zoster (shingles) and is of concern in patients on immunomodulatory 
therapy, including JAK inhibitors. Herpes zoster is an AE of interest in the ongoing long-
term safety evaluations. The underlying immune pathology and chronic use of drugs such as 
corticosteroids has also been associated with an increased risk of infection. 
− 
Malignancy:  
There have been no nonclinical findings that are directly relevant to malignancy. However, 
the risk of malignancies is increased in patients with UC, and immunomodulatory medicines 
may increase this risk. Clinical studies are insufficient to assess the potential risk following 
exposure to filgotinib. Long-term safety evaluations are ongoing. 
− 
Major adverse cardiovascular events (MACE) and hyperlipidemia: 
The association of JAK inhibitors and cardiovascular outcomes, including the potential for 
MACE as a result of elevations of lipid levels remains unclear. Filgotinib treatment was 
associated with dose-dependent increases in total cholesterol and high-density lipoprotein 
(HDL) levels, while low-density lipoprotein (LDL) levels were slightly increased, and 
LDL/HDL ratios were generally unchanged. Traditional cardiovascular risk factors (e.g. 
smoking, dyslipidemia, obesity, hypertension, diabetes mellitus, age, and cardiovascular 
history) may also apply to patients with UC. The Cardiovascular Safety Endpoint 
Adjudication Committee (CVEAC) will periodically review and adjudicate all potential 
MACE (refer to Section 10.1.1). 
− 
Venous thromboembolism (deep vein thrombosis [DVT] and pulmonary embolism [PE]): 
DVT and PE have been reported in patients receiving JAK inhibitors including filgotinib, but 
there is currently insufficient evidence indicating a causal relationship between filgotinib 
treatment and DVT/PE occurrence. The CVEAC will periodically review and adjudicate all 
potential thromboembolic events (refer to Section 10.1.1). 
− 
Embryolethality and teratogenicity:  
Embryolethality and teratogenicity were identified in nonclinical studies. It is not known 
whether these effects apply to humans exposed to filgotinib; however, similar effects from 
nonclinical studies with other medicinal products in the same class have been identified. The 
possible impact for a pregnant female participant taking filgotinib could be fetal death or a 
congenital anomaly. Filgotinib is contraindicated in pregnancy. 
− 
Impaired spermatogenesis, leading to possible reduction in male fertility: 
Filgotinib-related findings were observed in the male reproductive system of both rats and 
dogs. Spermatogenic and histopathological effects were reversible at lower exposures but 
were not completely reversible at exposure margins of approximately 7- to 9-fold the 
exposure at the 200 mg q.d. dose in humans. Based on the results of ongoing male safety 
studies to examine the potential effect of filgotinib on sperm parameters, it was concluded 
that there is no evidence of filgotinib-related effects on measures of testicular function at the 
marketed dose of 200 mg once daily (details are provided in IB Edition 17, Section 6.3.2). 
Information on important safety risks is included in the latest version of the IB and relevant 
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Risk Mitigation 
Due to the listed risk of infection, investigators are advised to monitor infections appropriately. 
Treatment interruption and discontinuation considerations surrounding infections are 
incorporated in the present protocol, and sites and investigators will be trained regarding such 
circumstances. Filgotinib should not be administered to patients with active TB. All subjects will 
be screened for TB and subjects with clinically significant active infections will be excluded. Use 
of live attenuated vaccines during filgotinib treatment is not recommended. 
Given this study will be performed during a severe acute respiratory syndrome coronavirus 2 
(SARS-CoV-2) pandemic, appropriate measures should be taken to minimize the risk of 
SARS-CoV-2 infection for subjects participating in the study as well as study site personnel. 
Local guidelines to prevent SARS-CoV-2 infection should be adhered to. 
HBV Surveillance  
− 
Subjects with positive HBV surface antigen (HBsAg) at screening were excluded from the 
parent UC studies (GS-US-418-3898 and GS-US-418-3899). Subjects who were positive for 
HBV surface antibody (HBsAb), but negative for both HBsAg and HBV core antibody 
(HBcAb) at screening were eligible to participate in the parent UC studies (GS-US-418-3898 
and GS-US-418-3899) and are also eligible to participate in the present study. 
− 
Subjects with positive HBcAb and HBV DNA below the lower limit of quantification 
(LLOQ) in a parent UC study will require ongoing HBV DNA monitoring every 12 weeks 
during the present study. After study primary analysis endpoint unblinding frequency will be 
reduced to every 24 weeks. These subjects may also require prophylactic treatment per 
investigator discretion in accordance with local guidelines/standard of care.  
− 
Any subject who has HBV DNA ≥LLOQ will be discontinued from the present study 
(Section 5.4.1.1 and Section 6.2 item 10).  
 
Malignancy has been reported in subjects on filgotinib. In the present study, subjects will be 
required to have up to date colorectal cancer screening and surveillance as per standard of care. 
Following SELECTION and SELECTION-LTE studies, subjects with recent malignancies will 
be excluded from the present study (Section 6.2, Item 9.1) and those diagnosed during the study 
will be discontinued, except successfully treated non-melanoma skin cancer or cervical 
carcinoma in situ. 
Highly effective contraceptive measures are expected to mitigate the risk of fetal toxicity. Refer 
to Section 6.3.1 for further guidance on pregnancy precautions and contraceptive requirements. 
For more details refer to the latest version of the IB and its relevant updates/addenda. 

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6. 
CLINICAL STUDY POPULATION 
6.1. 
Inclusion Criteria 
Subjects must meet all of the following inclusion criteria to be eligible for participation in this 
study: 
Signed Informed Consent Form 
1. Subject must be able and willing to comply with the CSP requirements and must sign and 
date the informed consent form (ICF) as approved by the Independent Ethics Committee 
(IEC) / Institutional Review Board (IRB), prior to any screening evaluations. 
Target Population 
2. Criterion modified per amendment 1. 
2.1 
Subjects must be participating in the SELECTION-LTE study, currently on 200 mg 
filgotinib q.d. and fulfill the following conditions: 
• 
pMCS remission1 over a period of at least 2 consecutive quarterly visits in the 
SELECTION-LTE study prior to screening of the present study; 
• 
free of corticosteroids for at least 12 weeks prior to and including baseline; 
• 
FCP <=250 µg/g at last observation within 6 months prior to screening or FCP 
<=250 µg/g during the screening of the present study. 
• 
sigmoidoscopy ES of 0 or 1 (local score) at screening. 
3. Subject must be able and willing to comply with restrictions on prior and concomitant 
medication (as described in Section 6.3.2). 
4. Willing to refrain from live attenuated vaccines during the study and for 12 weeks after the 
last dose of filgotinib in the study. 
Reproductive Status 
5. Female subjects of childbearing potential must have a negative highly sensitive (serum beta 
human chorionic gonadotropin) pregnancy test during screening, and must agree to 
continued monthly urine dipstick pregnancy testing during filgotinib treatment. 
6. Criterion modified per amendment 1. 
6.1 
Female subjects of childbearing potential must agree to use highly effective 
contraception measures as defined in Section 6.3.1.1.2. 
                                                 
1pMCS score ≤2 points, with PGA ≤1, stool frequency subscore ≤1, and rectal bleeding subscore = 0. 

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6.2. 
Exclusion Criteria 
Subjects meeting one or more of the following criteria cannot be selected for this clinical study. 
Medical History and Concurrent Diseases 
1. Any chronic medical condition (including but not limited to, cardiac or pulmonary disease, 
alcohol, or drug abuse) that, in the opinion of the investigator or sponsor would make the 
subject unsuitable for the study or would prevent compliance with the study protocol. 
 
Previous and Concomitant Medications 
2. Subject has taken any prohibited therapies before the planned first dose of IP. 
3. Subject concurrently participates or participated in a drug, drug/device, or biologic 
investigational research study with the exception of the preceeding SELECTION-LTE study 
within 12 weeks or 5 half-lives of the IP, whichever is longer, prior to the first dose. 
Allergies and Adverse Drug Reactions 
4. Subject has a known hypersensitivity to filgotinib ingredients or history of a significant 
allergic reaction to filgotinib ingredients as determined by the investigator. 
Other Exclusion Criteria 
5. Female subject who is pregnant or breastfeeding, or intending to become pregnant or 
breastfeed, and/or plans to undergo egg donation or egg harvesting for the purpose of current 
or future fertilization, during the study and until the end of the study. 
6. Criterion deleted per amendment 1. 
7. Subject is unable or unwilling to comply with restrictions regarding prior and concomitant 
medication as described in the protocol. 
8. Criterion modified per amendment 1. 
8.1  
Subject has a positive QuantiFERON® TB test at screening or has 2 indeterminate 
QuantiFERON® TB test results that require IP treatment interruption, or subject has signs 
and symptoms of TB reactivation at screening. 
9. Criterion modified per amendment 1. 
9.1 
History of malignancy during or in the last 5 years prior to participation in the UC 
parent studies, except for subjects who have been successfully treated for nonmelanoma skin 
cancer or cervical carcinoma in situ. 
10. Subject meets discontinuation criteria of the SELECTION-LTE study. 
11. Investigator or other study staff or relative thereof who is directly involved in the conduct of 
the study. 
12. Subject has any condition or circumstances that, in the opinion of the investigator, may make 
a subject unlikely or unable to complete the study or comply with study procedures and 
requirements (e.g. active alcohol or drug abuse). 

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13. Subject is institutionalized by virtue of an order issued by either the judicial or the 
administrative authorities, or has a dependence on the sponsor or investigator. 
6.3. 
Prohibition and Restrictions 
6.3.1. 
Precautions for Sexual Intercourse 
For participation in this study, the use of highly effective contraception is required as outlined 
below for all female subjects who are of childbearing potential. In addition, during the study 
women of childbearing potential (WOCBP) must have at minimum a urine pregnancy test every 
4 weeks. 
6.3.1.1. 
Female Subjects 
6.3.1.1.1. Definition of Childbearing Potential 
Woman of Childbearing Potential 
A female subject is considered of childbearing potential, i.e. fertile, following menarche and until 
becoming postmenopausal unless permanently sterile (see below). 
Woman of Non-childbearing Potential 
A female subject is considered of non-childbearing potential: 
1. Premenopausal female with permanent infertility due to one of the following documented 
conditions: 
a. 
hysterectomy 
b. bilateral salpingectomy 
c. 
bilateral oophorectomy 
d. For individuals with permanent infertility due to an alternate medical cause other than 
the above, (e.g. Mullerian agenesis, androgen insensitivity, gonadal dysgenesis), 
investigator judgment should be applied to determine study eligibility which should be 
properly documented. 
2. Postmenopausal female: 
The postmenopausal state is defined as: 
• 
no menses for ≥12 months without an alternative medical cause 
AND 
• 
confirmed high follicle stimulating hormone (FSH) level in the postmenopausal range. 
Note: If the FSH level is below the postmenopausal range while the female subject is 
using hormonal therapy, the postmenopausal state will be assessed by the investigator 
taking into account the subject’s age, medical records, medical examination, and/or 
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6.3.1.1.2. Contraceptive Methods 
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 during screening of 
the present study. Urine pregnancy tests will be performed at monthly intervals thereafter during 
filgotinib treatment. Female subjects must agree to continue to use one of the following 
contraceptive methods from screening, during the study, and until the end of the study: 
− 
complete abstinence from intercourse of reproductive potential. 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: 
• 
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); 
• 
vasectomy in the male partner (provided that the partner is the sole sexual partner and 
had confirmation of surgical success 3 months after procedure). 
Female subjects who utilize a hormonal contraceptive as one of their birth control methods must 
have consistently used the same method for at least 3 months prior to study dosing. 
Hormonally-based contraceptive methods permitted for use in this protocol are as follows: 
− 
oral contraceptives (either combined estrogen/progestin or progesterone only); 
− 
injectable progesterone; 
− 
implants of levonorgestrel; 
− 
transdermal contraceptive patch; 
− 
contraceptive vaginal ring. 
All female subjects must also refrain from egg donation and in vitro fertilization during the study 
and until the end of the study. 
The used contraceptive methods for female subjects must be documented in the source 
documents. 
Women of nonchildbearing potential are not required to use any contraceptive method. 
For information on the timing and requirements for pregnancy testing or FSH testing, refer to 
Section 8.4.2 and the Schedule of Activities. 
6.3.1.2. 
Male Subjects 
Section deleted per amendment 1. 

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6.3.1.3. 
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. Female condom and male condom should not be used together. 
6.3.1.4. 
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 30 days of the last IP dose. Subjects who become 
pregnant or who suspect that they are pregnant during the study must report the information to 
the investigator and discontinue the IP intake immediately.  
Instructions for reporting pregnancy, and pregnancy outcome are outlined in Section 11.3.3. 
6.3.2. 
Prior and Concomitant Medications 
6.3.2.1. 
Allowed Medications 
Doses for allowed concomitant medications for UC must be maintained at a stable dose. 
Discontinuation or dose modifications within the limits of allowed doses are permitted at the 
discretion of the investigator. 
The allowed medications for UC disease are as follows: 
− 
oral and rectal 5-aminosalicylate (5-ASA) compounds; 
− 
azathioprine, 6-mercaptopurine or methotrexate; 
− 
rectally administered, nonsystemically absorbed steroids (except for at least 12 weeks prior 
to screening and including baseline of the present study); 
− 
antidiarrheals (e.g. loperamide or diphenoxylate/atropine). 
Oral and/or rectal corticosteroids are allowed in case of flare (see Section 5.1), and oral 
corticosteroids should not exceed prednisone 30 mg/day equivalents. 
6.3.2.2. 
Prohibited Medications 
A list of prohibited medications is provided in Table 1. 

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Table 1: 
Prohibited Medications 
Drug Class 
Prohibited Agents 
Prohibited inflammatory bowel disease medication 
Corticosteroids (intravenous)a 
 
TNF alpha agonist 
Infliximab, adalimumab, golimumab, certolizumab, or 
biosimilar agent 
Integrin antagonist 
Vedolizumab and natalizumab 
Interleukin antagonist 
Ustekinumab 
JAK inhibitor 
Any JAK inhibitors including, but not limited to, 
tofacitinib, baricitinib, and updadacitinib 
Other (nonbiologics) 
Cyclosporine, thalidomide, tacrolimus, ozanimod, 
leflunomide and any investigational agent 
Investigational biologics 
Any investigational biologic agent 
Lymphocyte-depleting therapies 
Alemtuzumab, cyclophosphamide, total lymphoid 
irradiation, rituximab, and any other lymphocyte-
depleting therapy 
Other probited Medications 
Chronic nonsteroidal anti-inflammatory drugs 
(NSAIDs)b 
Aspirin, ibuprofen, naproxen, diclofenac, 
indomethacin, cyclooxygenase-2 (COX-2) inhibitors 
Other biologics 
Antibody based or other systemic biologics, e.g. 
denosumab, trastuzumab 
a Oral and/or rectal corticosteroids  may be used in case of a flare (see Section 5.1), and oral corticosteroids should not exceed prednisone 30 
mg/day equivalents (except for at least 12 weeks prior to screening and including baseline of the present study). 
b Occasional use for transient symptoms and daily use of aspirin up to 162.5 mg for the purpose of cardiovascular prophylaxis are permitted 
 
6.3.3. 
Food and Beverage Restrictions 
There are no specific food and beverage restrictions for this study. The IP can be taken with or 
without food. There are no specific requirements regarding IP and the dietary intake. 
6.4. 
Measures to Minimize Bias 
6.4.1. 
Randomization 
Subjects will keep the subject number received in the SELECTION-LTE study. When a subject 
is confirmed to be eligible for the clinical study, the subject will be randomized. Allocation of 
each subject to a given treatment will be done using a centralized electronic system 
(randomization and trial supply management [RTSM]). Subjects will be randomized in a 1:1 ratio 
to 200 mg or 100 mg filgotinib q.d. Subjects will be stratified according to ES (score of 0 or 1) at 
baseline to ensure treatment balance in each stratum. 
6.4.2. 
Blinding and Unblinding 
This is a randomized, double-blind clinical study. The subjects and the entire clinical study team, 
including the investigators, clinical study coordinators, and sponsor personnel are blinded to 

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treatment assignment until the study primary analysis time point, with the exception of the 
sponsor’s clinical study supply leader. 
Unblinding will take place at the study primary analysis time point, i.e. after the last subject 
completed their Week 48 postbaseline visit or has completed their Week 12 post re-escalation 
visit (if baseline of re-escalation is within the first 48 weeks of the study), or after the last follow-
up of subjects discontinuing prior to Week 48, whichever comes last. Unblinding at the Week 48 
interim analysis is described in Section 9.3.2. In addition, 
 
 external functions 
specified in RTSM specification, will also be unblinded to treatment assignment. 
Study medication provided to the sites will be packaged and labeled assuring the blinding of the 
IP. Unblinded study medication will be provided for treatment in case of re-escalation and for 
treatment after unblinding. Subjects who are re-escalated to 200 mg filgotinib q.d. will remain 
blinded to their treatment at randomization. 
The blind can be broken only if the investigator deems it necessary for the safety of a subject. 
The investigator is encouraged to discuss considerations to break the blind with the medical 
monitor of the study, whenever possible and where the situation allows. However, the 
responsibility to break the treatment code in emergency situations resides solely with the 
investigator. The investigator is not required to discuss unblinding beforehand if he or she feels 
rapid emergency unblinding is necessary, but is required to inform the sponsor within 24 hours 
after unblinding has occurred. 
The blind can be broken by the investigator via RTSM. 
If the blind is broken for any reason during the course of the clinical study, all relevant 
information will be documented by the site. The reason for breaking the blind will be indicated 
and justified in the source documentation. 
In case an AE leads to unblinding, that AE should be given as the reason for unblinding. 
The pharmacovigilance department of the sponsor (or a representative thereof) may 
independently unblind cases for expedited reporting of suspected unexpected serious adverse 
reactions (SUSARs) to worldwide regulatory agencies (see Section 11.4). 
7. 
INVESTIGATIONAL PRODUCT 
7.1. 
Identity of the Investigational Product 
Filgotinib is available as 200 mg and 100 mg strength tablets. Filgotinib tablets, 200 mg and 
100 mg are beige, debossed with “GSI” on one side and “200” or “100” on the other, 
capsule-shaped, biconvex, film-coated tablets for clinical use. Each tablet contains the equivalent 
of 200 mg or 100 mg filgotinib free base in the form of filgotinib maleate. In addition to the 
active ingredient, filgotinib tablets contain the following inactive ingredients: microcrystalline 
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stearate, macrogol/polyethylene glycol (PEG) 3350, polyvinyl alcohol, talc, titanium dioxide, 
iron oxide yellow, and iron oxide red. 
Placebo-to-match (PTM) 200 mg and 100 mg filgotinib tablets are identical in appearance to the 
respective active filgotinib tablets. PTM 200 mg and 100 mg 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. 
7.2. 
Dosage and Administration 
The IP needs to be taken q.d. at approximately the same time. Subjects will be asked to swallow 
the IP with a glass of water and to not chew the drug prior to swallowing. The IP can be taken 
with or without food. There are no specific requirements regarding IP and the dietary intake.  
Blinded treatment up to the primary analysis time point 
Doses of 100 mg or 200 mg filgotinib, as a combination of 2 tablets (filgotinib and PTM) for 
blinding purposes, will be taken q.d. orally. 
Subjects will be provided with medication kits containing 2 bottles with blinded IP, either: 
− 
100 mg filgotinib tablets in bottle 1 and PTM 200 mg filgotinib tablets in bottle 2; 
− 
200 mg filgotinib tablets in bottle 1 and PTM 100 mg filgotinib tablets in bottle 2. 
At the baseline visit (Day 1), IP will be administered on-site after predose assessments have been 
completed. If on Day 1, the subject has already taken the IP as assigned in the SELECTION-LTE 
study, the first dose as assigned in this study should be taken on Day 2. 
Starting from Day 2, subjects will be instructed to take 1 tablet from each bottle q.d. (i.e. a total 
of 2 tablets). 
Re-escalation 
Subjects who are re-escalated to open-label 200 mg filgotinib q.d. will be provided with bottles 
containing unblinded IP (200 mg filgotinib tablets in 1 bottle). If the subject has already taken IP 
on the re-escalation baseline day, the first adjusted dose should be taken on re-escalation Day 2. 
Subjects will be instructed to take 1 tablet q.d. 
Subjects who are re-escalated continue on open-label 200 mg filgotinib q.d. for at least 12 weeks. 
If the subject does not respond to re-escalation therapy within a timeframe of maximum 
12 weeks, the subject will be permanently discontinued from the treatment. If subject 
improvement is sufficient in the opinion of the investigator, the subject may continue on open-
label 200 mg filgotinib q.d. until the end of the study. 

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After unblinding at the primary analysis time point 
For continued q.d. treatment after unblinding until the end of the study, subjects will be provided 
with bottles containing unblinded IP, either: 
− 
1 bottle with 100 mg filgotinib tablets; 
− 
1 bottle with 200 mg filgotinib tablets. 
Subjects will be instructed to take 1 tablet q.d. 
At each IP dispensing visit, subjects will receive IP to take home on non-study visit days and will 
be provided with instructions for dosing. Multiple medication kits can be provided to ensure the 
subject has sufficient tablets to cover the period until the next visit when IP dispensing is 
scheduled. 
If a subject misses a dose (e.g. because he/she forgot to take the medication), he/she should take 
the missed dose as soon as possible during the same day of the planned intake time, or else that 
dose should be skipped. If a dose is not taken it should be returned to the bottle. 
7.3. 
Packaging, Labeling, and Distribution 
Filgotinib and PTM filgotinib tablets are packaged in white, high-density polyethylene 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. The IP to be distributed to centers in the United States 
(US), EU, and other participating countries shall be labeled to meet applicable requirements of 
the US Food and Drug Administration, EU Guideline to Good Manufacturing Practice – 
Annex 13 (Investigational Medicinal Products), and/or other local regulations, as applicable. 
The distribution of IP to the site will only occur after the required local documentation is 
obtained, including clinical study approval by regulatory authorities and the IECs/IRBs, 
documentation on which the assessment of the investigator’s qualifications was based (e.g. 
curriculum vitae), and the signed and dated clinical study agreement. 
In case of travel restrictions (including due to SARS-CoV-2 pandemic), to ensure study subjects 
maintain dosing per protocol requirements during this study, special delivery services through 
Direct to Patient (DTP) shipments of IP to the subject can be implemented. DTP shipments 
should only be used in case of emergency when on-site IP dispensation is not possible, and if 
allowed per local regulations. Local guidelines must be followed and regulatory approval or 
notification of authorities may be required. Agreement of the subject to receive IP at home is 
required prior to the shipment of IP to the subject’s home. The DTP shipment process used will 
be reviewed and approved by the sponsor. In case the DTP shipments originate from the site they 
will be coordinated by the investigational site(s) in collaboration with the local CRO without the 
involvement of the sponsor, to ensure clinical study integrity. 

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7.4. 
Storage 
Sites must store IP supplies in a secure temperature-controlled area at room temperature 
(15-25 °C; excursions permitted between 15 °C and 30 °C) until dispensed. Sites are required to 
monitor the storage temperature by using at least a min-max temperature recording device and to 
record each working day the minimum and maximum temperature (either by the temperature 
recording device or in a temperature log). This is to establish a record of compliance with these 
storage conditions. The investigator will instruct subjects how the IP should be stored at home. 
7.5. 
Treatment Compliance and Drug Accountability 
The investigator must discuss treatment compliance with the subject prior to the start of the 
study. Missed doses should be discussed to try to ascertain the reason(s). Every effort should be 
made to ensure the proper subject dose. Subjects with poor compliance will be retrained by the 
site. IP administration as indicated by the subject (amounts as well as periods) will be recorded 
on the case report form (CRF). 
The pharmacist or designated clinical study staff will maintain a log (paper or electronic) of the 
total amount of IP received at site, amount dispensed to the subject, and the amount of IP 
returned by the subject to the site. IP supplies for each subject will be inventoried and accounted 
for throughout the clinical study. On an ongoing basis and at the end of the treatment period, 
these records will be checked against the inventory by the study monitor. All clinical supplies 
will be stored in locked facilities. 
Subjects will return any unused IP and empty IP packages at every dispensing visit, unscheduled 
visit, and/or ED visit. All used and unused IP, and packages are to be returned from the sites 
and/or any vendor involved in the clinical study supplies management activities to the agreed 
location (depot), if possible. Only in exceptional cases, upon sponsor approval, IP can be 
destroyed at the site. All returns and destructions must be properly documented. 
8. 
CLINICAL STUDY ASSESSMENTS 
Every effort must be made to ensure that CSP-required tests and procedures are completed as 
described in the Schedule of Activities (see Section 8.9.1 and Section 8.9.2). To avoid inter-
observer variability, every effort should be made to ensure that clinical observations are 
performed by the same individual who made the initial baseline determinations. 
8.1. 
Timing of Assessments 
The study assessments described below will be performed at time points as specified in the 
Schedule of Activities in Section 8.9.1 and Section 8.9.2. 
The ICF needs to be signed before any study procedure, including screening procedure, is carried 
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Subjects in the SELECTION-LTE study who are in clinical remission with 200 mg filgotinib q.d. 
for at least 2 consecutive quarterly visits, will be provided the option to roll over to the present 
study at any scheduled visit of the SELECTION-LTE study or at a separate visit. 
Subjects will be requested to attend the site for at least 2 screening visits: 
− 
Screening visit 1 (ICF signature) (S1) and other screening assessments as per Schedule of 
Activities in Section 8.9.1, including TB assessment and screening FCP assessment (if last 
FCP observation was >6 months prior to screening or most recent FCP value was >250 µg/g) 
in order to obtain the results prior to randomization. 
 
Depending on the screening FCP in the present study (if applicable) and the ES, the subject 
will either be a screening failure (FCP >250 µg/g or ES >1) in the present study and will 
remain in SELECTION-LTE, or the subject will be eligible (FCP ≤250 µg/g and ES ≤1) and 
will need to perform the EoT assessments in SELECTION-LTE and the remaining screening 
assessments before being randomized to the present study (refer to Schedule of Activities in 
Section 8.9.1).  
− 
Screening visit 2 (S2), the EoT visit in SELECTION-LTE, and the Day 1 visit of the present 
study can occur on the same day or on 2 consecutive days. 
Some data collected in SELECTION-LTE, as specified in the Schedule of Activities in 
Section 8.9.1, may be used in the present study. 
In case a randomized subject is not able to attend a scheduled study visit on-site for reasons 
related to SARS-CoV-2 pandemic restrictions, a phone call or a televisit may be conducted 
(televisit after obtaining approval from the sponsor). It is strongly recommended to conduct 
planned study assessments for the applicable visit as per protocol as much as possible. If possible 
and if local regulations allow, and the subject agrees, trained site study staff are encouraged to 
perform study assessments at the study subjects’ home or a local facility. Only staff trained in 
conducting the protocol planned assessments are authorized to perform home or local facility 
visit assessments and the alternative arrangements need to be adequately documented.  
DTP shipments are possible, if needed, in case of travel restrictions (e.g. due to SARS-CoV-2 
pandemic), and if allowed per local regulations (refer to Section 7.3). 
8.1.1. 
Order of Assessments 
For assessments to be performed at screening visits, refer to the Schedule of Activities in 
Section 8.9.1. 
In case the following assessments are planned to be performed at the same time point, they need 
to be performed in the following order: 
 
2. 12-lead electrocardiogram (ECG) and vital signs; 
3. blood sampling for clinical laboratory assessments, 
 

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For other assessments planned to be performed at the same time point, a random order is allowed. 
 
 
8.1.2. 
End of Treatment Visit 
In countries where filgotinib becomes commercially available, subjects will be requested to 
attend the EoT visit as soon as possible after the subject has completed at least 48 weeks of 
treatment (see Section 5.1). For the subjects who have not yet completed 48 weeks of treatment 
when filgotinib becomes commercially available, the Week 48 visit can replace or occur on the 
same day as the EoT visit. All assessments listed at the EoT visit can be conducted as part of the 
Week 48 visit; therefore the EoT assessments do not need to be repeated. If not performed on the 
same day, there should be a minimum of 1 week and maximum of 4 weeks between the 2 
assessments, and the TB assessment at Week 48 suffices for TB assessment at EoT. Other 
assessments for the EoT visit should be performed according to the Schedule of Activities 
(Section 8.9). 
8.1.3. 
Re-screening of Subjects 
If a subject fails screening, it is allowed to re-screen the subject once. Re-screening may only be 
conducted after approval from the sponsor’s medical lead. When a subject is re-screened, the 
subject needs to be reconsented and all screening assessments need to be repeated. The subject 
will be assigned a new subject number.  
8.1.4. 
Unblinding of Subjects at the Study Primary Analysis Time Point 
After unblinding at the study primary analysis time point, subjects will receive unblinded 
treatment and the frequency of study visits will be reduced to every 24 weeks. All subjects should 
be invited for an unblinding visit no later than 4 weeks after the study primary endpoint 
unblinding. If no regular visit is scheduled within this time frame, an unscheduled visit should be 
performed for IP dispensing to ensure the subject has sufficient IP to cover the period until the 
next 24-weekly visit. Assessments indicated as to be performed every 12 weeks will then be 
added to the assessments at Week 24. 
The unblinded treatment duration depends on commercial availability of filgotinib in the country 
but will be limited to the maximum study duration for individual subjects of 216 weeks. 
8.2. 
Unscheduled Visits 
Additional visits can be performed at other time points for IP dispensing and /or any safety 
assessments, if clinically indicated. These unscheduled visits and outcomes of additional safety 
assessments need to be recorded in the source and, if it is a CSP-specified safety assessment 
performed before the subject’s last visit per CSP, also in the CRF. 

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8.3. 
Efficacy Assessments 
8.3.1. 
Endoscopy and Biopsy Sample Collection 
A sigmoidoscopy will be performed at the visits specified in the Schedule of Activities in 
Section 8.9.1. 
The ES for randomization purposes will be obtained from a sigmoidoscopy performed during the 
screening period (including biopsy collection for histology assessment). It is recommended that 
the screening sigmoidoscopy be performed only after the subject meets all other eligibility 
criteria. 
In case of a suspected UC flare, an additional sigmoidoscopy is needed (refer to Section 5.1). 
Subjects who discontinue the study prior to Week 48 need a sigmoidoscopy at the ED visit. 
The endoscopy will be assessed by a local reader and scored using the Mayo scoring system 
(refer to Section 8.3.2). 
 
 
 
8.3.2. 
Mayo Clinical Score 
The Mayo scoring system for assessment of UC activity is shown in Appendix 2. The total MCS 
consists of 4 subscores (stool frequency, rectal bleeding, endoscopic findings, and PGA). 
The primary efficacy objective will be assessed based on the mMCS. The mMCS is composed of 
3 subscores: stool frequency, rectal bleeding, and endoscopic findings. 
 
 
Stool frequency and rectal bleeding scores will be established based on the subject’s e-Diary. 
PGA will be completed electronically by the investigator. 
 
 

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8.3.3.4. 
IBDQ 
This disease-specific questionnaire comprises 32 questions divided into 4 health subscales: 
− 
bowel symptoms (10 questions); 
− 
systemic symptoms, including sleep disorders, and fatigue (5 questions); 
− 
emotional function such as depression, aggression, and irritation (12 questions); 
− 
social function, meaning the ability to participate in social activities and to work 
(5 questions). 
8.4. 
Safety Assessments 
This section describes methods for all safety assessments and recording. Additional assessments 
(e.g. unscheduled clinical laboratory evaluations or extra vital signs recordings) are allowed to 
ensure appropriate collection of safety data and to assess any perceived safety concerns. 
Retesting is allowed in case no results from the assessment(s) are available due to subject-
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Clinically significant abnormal findings should be recorded as AE as indicated in Section 11.1.5. 
8.4.1. 
Adverse Events 
The AE reporting period for safety surveillance begins when the subject signs the ICF and ends at 
their last scheduled visit. 
Detailed definitions, reporting period, ratings and reporting requirements for AEs and SAEs are 
found in Section 11. 
8.4.2. 
Clinical Laboratory Evaluations 
The clinical laboratory evaluations (listed in Appendix 3) will be performed at visits and time 
points specified in the Schedule of Activities in Section 8.9.1 and Section 8.9.2 (see also 
Section 8.1, “Timing of Assessments”). Reference ranges will be supplied by the central 
laboratory. Clinical laboratory values outside the normal range will be flagged and clinical 
relevance will be assessed by the investigator. Only laboratory test abnormalities judged as 
clinically significant by the investigator should be recorded as AEs (see Section 11.1.5). At the 
discretion of the investigator, when following up AEs, additional laboratory parameters may be 
tested, and additional samples taken. 
Clinical and clinically significant laboratory abnormalities will be managed according to uniform 
guidelines detailed in Appendix 4. 
Blood and urine sample handling, and shipment instructions will be provided in a separate 
laboratory manual. 
8.4.3. 
Physical Examination 
Physical examinations, including height (only during screening) and weight, will be conducted by 
a physician or a trained physician’s assistant, as acceptable according to local regulation at visits 
specified in the Schedule of Activities in Section 8.9.1 and Section 8.9.2 (see also Section 8.1, 
Timing of Assessments). 
Physical examinations will be symptom-directed. 
The person conducting the physical examination will document this in the subject’s source 
documents. 
8.4.4. 
Vital Signs 
Vital signs (systolic and diastolic blood pressure, pulse, respiratory rate, and body temperature) 
will be measured. 
Vital signs values will be recorded in a standardized manner at visits specified in the Schedule of 
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• 
systolic and diastolic blood pressure and pulse: after the subject has rested in a seated or 
supine position for 5 minutes; 
• 
respiratory rate; 
• 
body temperature: oral or tympanic (consistent method to be used at every time point 
within the same subject). 
8.4.5. 
12-lead Electrocardiogram 
At the time points specified in the Schedule of Activities (see Section 8.9.1 and also Section 8.1, 
“Timing of Assessments”), a 12-lead ECG will be recorded. 
12-lead ECG recordings will be performed before blood sampling and after subjects rested for 
5 minutes in supine position. In case an indwelling catheter is used, ECGs may be recorded after 
blood sampling, provided that there is at least 30 minutes between catheter insertion and the ECG 
recording. When catheter insertion would fail, the 12-lead ECG needs to be taken before the 
venipuncture and at least 30 minutes after the failed attempt.  
The following parameters need to be recorded: heart rate, PR interval, QRS interval, uncorrected 
QT interval, morphology, and rhythm analysis. 
The ECG will be reviewed by the investigator to detect clinically significant abnormalities. This 
review during the visit needs to be documented in the subject’s source documents.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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8.7.2. 
Blood and Urine Samples for Routine Safety Tests 
All blood and urine samples for routine safety tests (see Section 8.4.2) will be analyzed in a 
central laboratory and will be destroyed after analysis as per laboratory procedure (unless 
otherwise indicated in Section 8.8). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
8.8. 
Optional Long-term Storage of Samples and Associated Data for 
Future Clinical and Research Assessments 
Left-over samples from samples already collected during the study and associated data (e.g. 
sample type, quantity, treatment name) qualify for long-term storage for use as part of future 
scientific research if subjects have agreed to participate and provide their optional informed 
consent. Blood (serum and plasma), stool samples, and biopsy samples will be stored. Samples 
that qualify for long-term storage will be stored for 30 years or according to local legislation, for 
future scientific research. 
The sample(s) and associated data collected for future scientific research will be stored in the 
Galapagos Biobank and may be used by the sponsor, sponsor partners, and/or other companies 
contracted by the sponsor. The objective of biobanking is to allow the gathering of additional 
knowledge on the compound GLPG0634 and/or diseases it may target both investigated during 
this study and beyond. 
No characterization of human genetic material (genes, DNA, or RNA) will be undertaken on 
these sample(s).  
Subjects are not required to consent for the long-term storage of sample(s) and associated data for 
future scientific research in order to participate in the study. Subjects will also be informed that 
consent to storage for future scientific research is voluntary and that they may withdraw their 
consent at any time. If a subject chooses to withdraw consent for the storage of sample(s) and 

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associated data for future research after the end of the study, then the investigator or designated 
personnel must inform the sponsor (withdrawal@glpg.com). 
Withdrawal from the study or 
does not, by itself, implicate withdrawal of consent 
for the storage of sample(s) and associated data for future research. Likewise, withdrawal of 
consent for the storage of sample(s) and associated data for future research does not implicate 
withdrawal from the study or 
 
In the event of subject’s death or loss of competence, the already collected sample(s) and data 
will continue to be used as part of the future scientific research only for the purposes as described 
in the ICF that was signed by the subject. 
The sample(s) and associated data for future research, e.g. body fluids, solid tissue, and 
derivatives thereof (e.g. protein, peptides) will be destroyed no later than 30 years after the end of 
the study or according to local legislation. The sample(s) and associated data storage period will 
be in accordance with the IRB/EC-approved ICF and applicable legislation (e.g. regulatory 
authority requirements). 
The subject will receive additional information specific to the long-term processing of their 
personal data for future scientific research purposes, as required by the EU General Data 
Protection Regulation. This includes information about the broader scientific purposes of future 
research, the lawful bases of the processing activities involved, as well as the retention period of 
their personal data for these additional purposes. The details are included in the optional ICF. 

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8.9. 
Schedule of Activities 
For additional information on the timing of the clinical study procedures, please see Section 8.1, “Timing of Assessments”. 
8.9.1. 
Regular Schedule of Activities 
EVENT 
SCREENING 
PERIOD 
TREATMENT PERIOD 
FOLLOW-UP 
PERIOD 
Study Day (D)/ Week (W)  
S1a 
S2 
Day 1b 
W4 
W12 and then 
every 12 weeks 
W24 and then 
every 24 weeks 
W48 c and then
every 48 weeks 
ED 
EoTd 
4 weeks after 
last IP dose 
(EoS) 
D-28 to D-1 
 
± 3 days 
± 7 days 
± 7 days 
± 7 days 
 
 
± 3 days 
Informed consent  
✓ 
 
 
 
 
 
 
 
 
 
TB assessment e 
✓ f 
 
 
 
 
 
✓ 
 
✓ 
 
Sigmoidoscopy g  
including biopsy collection  
✓ h 
 
 
 
 
✓ 
✓ i 
 
 
                                                 
a Screening visit 1 (S1) may occur at the same time as any scheduled visit of the SELECTION-LTE study or as a separate visit. 
b Screening visit 2 (S2) and the Day 1 visit can occur on the same day or on 2 consecutive days. 
c After unblinding at the study primary analysis time point, subjects will receive unblinded treatment and the frequency of study visits will be reduced to every 24 weeks with 
an allowed window of ±10 days (see Section 8.1.4).  
d In countries where filgotinib becomes commercially available, the study will be terminated for the subjects who have already completed at least 48 weeks of treatment. 
Subjects will then be requested to attend the EoT visit as soon as possible (see Section 5.1). For the subjects who have not yet completed 48 weeks of treatment when 
filgotinib becomes commercially available, the Week 48 visit can replace or occur on the same day as the EoT visit. All assessments listed at the EoT visit can be conducted 
as part of the Week 48 visit; therefore EoT assessments do not need to be repeated.  
e Subjects who have been previously treated for TB with a complete and adequate course of therapy as per local standard of care and as verified by the investigator and do not 
need to have yearly QuantiFERON® tests should only be screened for signs and symptoms of reactivation at the time of screening and at visits as indicated in the Schedule of 
Activities. 
f Blood sample for QuantiFERON® test, if applicable, at S1 needs to be taken after signing ICF, preferably 4 weeks before Day 1 to obtain the TB assessment result before 
randomization. An indeterminate result should be repeated once and the second result (if positive or negative) will be accepted. Subjects who had 2 sequential indeterminate 
QuantiFERON® tests or a positive QuantiFERON® test during any of the visits of the SELECTION-LTE but do not have active or latent TB at the time of screening, as 
 

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EVENT 
SCREENING 
PERIOD 
TREATMENT PERIOD 
FOLLOW-UP 
PERIOD 
Study Day (D)/ Week (W)  
S1a 
S2 
Day 1b 
W4 
W12 and then 
every 12 weeks 
W24 and then 
every 24 weeks 
W48 c and then
every 48 weeks 
ED 
EoTd 
4 weeks after 
last IP dose 
(EoS) 
D-28 to D-1 
 
± 3 days 
± 7 days 
± 7 days 
± 7 days 
 
 
± 3 days 
Inclusion/exclusion criteria 
✓ 
Prerandom-
ization 
 
 
 
 
 
 
 
Demographics  
✓
 
 
 
 
 
 
 
 
Medical history  
✓ 
 
 
 
 
 
 
 
 
Pregnancy test 
✓j
 
✓j
✓j
 
 
✓j
✓j
✓j
FSH test k 
✓
 
 
 
 
Physical examination (symptom-
directed) 
 
✓l 
 
✓ 
✓ 
 
 
✓ 
✓ 
✓ 
Vital signs  
 
✓l 
 
✓ 
✓ 
 
 
✓ 
✓ 
✓ 
Height  
✓ 
 
 
 
 
 
 
 
 
Weight 
✓ l 
 
✓ 
✓ 
 
 
✓ 
✓ 
✓ 
                                                 
verified by the investigator, or had latent TB and underwent adequate treatment and continued in the SELECTION-LTE, are not required to have a screening QuantiFERON® 
test. In this case, the subject must be screened for signs and symptoms of TB reactivation. 
g Sigmoidoscopy during screening, at Week 48 and every 48 weeks thereafter, and ED (if applicable), in fasting condition, as per local guidance. In case of a suspected UC 
flare, an additional sigmoidoscopy is needed. Two biopsies should be collected during every sigmoidoscopy performed during the study. 
h Bowel preparation for screening sigmoidoscopy can only start after signing ICF. 
i Subjects who discontinue the study prior to Week 48 require a sigmoidoscopy at the ED visit. 
j WOCBP only. Serum pregnancy test during screening; urine dipstick pregnancy test at the Week 4 visit, thereafter at the site every 12 weeks, and in-between every 4 weeks 
at home (±3 days). If a urine test cannot be confirmed as negative (e.g. an ambiguous result), a serum pregnancy test is required to confirm.  
k For postmenopausal women only. 
l Could be taken from SELECTION-LTE. In case assessments listed at S2 are conducted as part of the EoT visit in SELECTION-LTE, the assessments do not need to be 
repeated and assessment results may be used. 
 

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EVENT 
SCREENING 
PERIOD 
TREATMENT PERIOD 
FOLLOW-UP 
PERIOD 
Study Day (D)/ Week (W)  
S1a 
S2 
Day 1b 
W4 
W12 and then 
every 12 weeks 
W24 and then 
every 24 weeks 
W48 c and then
every 48 weeks 
ED 
EoTd 
4 weeks after 
last IP dose 
(EoS) 
D-28 to D-1 
 
± 3 days 
± 7 days 
± 7 days 
± 7 days 
 
 
± 3 days 
Hematology 
 
✓ l, m 
 
✓ 
✓ 
 
 
✓ 
✓ 
✓ 
Chemistry 
 
✓l, m 
 
✓ 
✓ 
 
 
✓ 
✓ 
✓ 
Lipid profile (fasted n) 
 
✓ l, m 
 
 
 
✓ 
 
 
✓ 
 
Urine analysis 
 
✓l, m 
 
 
 
✓ 
 
 
✓ 
 
HBV DNA monitoring o 
 
✓ l 
 
 
✓ 
 
 
 
✓ 
 
12-lead ECG 
 
✓ l 
 
 
 
 
✓ 
 
✓ 
 
Serum immunoglobulin 
 
✓ l 
 
 
 
✓ 
 
 
✓ 
 
CRP 
 
✓ l 
 
✓ 
✓ 
 
 
✓ 
✓ 
 
Fecal calprotectin p  
✓q  
✓ l,r 
 
✓ 
✓ 
 
 
✓ 
✓ 
 
                                                 
m Screening clinical laboratory results may only be available after randomization. In that case,  these results will be reviewed after randomization and subjects with laboratory 
results meeting discontinuation criteria, will be discontinued from the study. 
n Subjects should remain fasted for at least 8 hours, excluding water. 
o Only subjects with positive HBcAb and HBV DNA <LLOQ in a parent UC study will require ongoing HBV DNA monitoring every 12 weeks during the present study, and 
after study primary endpoint unblinding every 24 weeks. 
p Stool samples need to be taken prior to bowel preparation for endoscopy. Stool samples can be collected within 24 hours prior to the visit or during the visit. 
q FCP should be assessed during screening if the last assessment during SELECTION-LTE was >6 months prior to screening or the most recent value was >250 µg/g. 
r This FCP assessment should be obtained at the EoT visit in SELECTION-LTE (i.e. performed after the subject is fully eligible to roll over to the present study) and will be 
the baseline of the present study. In case FCP was not obtained at the EoT visit of SELECTION-LTE, an unscheduled stool sample should be collected within 24 hours prior 
to or during Day 1 (i.e. predose). 
 

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9. 
STATISTICAL METHODS 
All statistical methods shall be detailed in a statistical analysis plan (SAP). The SAP will be 
finalized prior to the interim analysis (see Section 9.3.2) and unblinding. All relevant data 
collected in this clinical study will be documented using summary tables, figures, and subject 
data listings. 
Any deviations from the CSP are to be justified in the SAP. 
9.1. 
Determination of Sample Size 
The primary objective is to estimate the difference in remission rates at Week 48 between 200 mg 
filgotinib q.d. and 100 mg filgotinib q.d. No formal hypothesis testing will be conducted. 
The sample size is determined based on the desired level of precision (half width of the 95% CI) 
of the estimated treatment difference between 200 mg filgotinib q.d. and 100 mg filgotinib q.d. in 
the percentage of subjects meeting corticosteroid-free1 mMCS remission criteria at Week 48. The 
level of precision determines the range in which the treatment difference is estimated to be. This 
range is expressed in percentage points. 
The highest variability in the estimation of the treatment effect (i.e. CI with the lowest precision, 
or largest width) is observed when the remission rate is 50%. Figure 2 shows the worst-case 
precision for a range of observed treatment differences when the remission rate is 50% in at least 
one treatment group for a fixed set of possible sample sizes ranging from 30 subjects to 
70 subjects per group (assuming 2 groups of equal size). Continuity-corrected Newcombe 
confidence limits were used to calculate the precision. The precision is better if the actual 
observed remission rates differ from 50%. A sample size of 40 subjects per group will guarantee 
a worst-case precision of maximum 22.5%. 
                                                 
1 Free of corticosteroids for at least 12 weeks. 

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Figure 2: 
Worst-case Precision for a Range of Sample Sizes Using Newcombe Continuity-
corrected CIs With 50% Remission Rate in at Least 1 Group 
Figure 3 shows the precision achieved for a range of potential treatment differences for a sample 
size of 80 subjects. With 40 subjects per group, the estimated half width of the 95% CI for the 
treatment difference between filgotinib 200 mg q.d. and 100 mg q.d. will lie within 11% and 
22.5%. 

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Figure 3: 
Precision for a Sample Size of 40 Subjects per Group Using Newcombe 
Continuity-corrected CIs 
9.2. 
Population for Analyses 
9.2.1. 
All Screened Subjects 
All subjects who signed and dated an ICF. 
9.2.2. 
All Randomized Subjects 
All screened subjects who were randomized into the clinical study. 
9.2.3. 
Full Analysis Set 
All randomized subjects who have received at least 1 dose of IP. 

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9.2.4. 
Safety Analysis Set 
All randomized subjects who received at least 1 dose of IP (same as full analysis set [FAS]). 
 
 
 
 
9.3. 
Statistical Analyses 
9.3.1. 
General Statistical Considerations 
Summary tabulations will be presented and will display the number of observations, mean, 
standard deviations (SDs) and/or standard error (SE) (as appropriate), median, minimum and 
maximum (for continuous variables), and the number and percentage per category (for 
categorical data). In addition to tabulated descriptive statistics, graphical data displays may be 
used to summarize the data. 
Baseline is defined as the last available assessment prior to the first intake of IP in the current 
study. 
9.3.2. 
Interim Analysis 
An interim analysis is planned for this clinical study. 
The data collected from this study will be analyzed at 2 time points. An unblinded interim 
analysis of the clinical study data will be performed by the sponsor on cleaned and locked data, 
after the last subject completed their Week 48 postbaseline visit or has completed their Week 12 
post re-escalation visit (if baseline of re-escalation is within the first 48 weeks of the study), or 
after the last follow-up of subjects discontinuing prior to Week 48, whichever comes last. This 
analysis will be the primary analysis. The analyses will be conducted on efficacy data up to 
Week 48 and safety data up to the data cut-off date, to be able to evaluate the primary, secondary, 
and exploratory efficacy endpoints, and safety. The subjects and the clinical study team will be 
unblinded at the time of the Week 48 analysis (for details, refer to Section 6.4.2). 
The final analysis will be performed after the global end of the study (i.e. date of the last visit for 
the last subject in the last country) and the database is cleaned and locked. At the final analysis, 
all available efficacy and safety data will be summarized using descriptive statistics. 
Details on the interim analysis and the final analysis will be further described in the SAP. 
9.3.3. 
Analyses of Demographics and Baseline Characteristics 
Subject disposition (including reasons for ED), CSP deviations, demographics, baseline 
characteristics, medical history, and concomitant therapies will be analyzed descriptively. 
Baseline will be defined as the last measurement before the first dose of IP in the present study. 

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9.3.4. 
Analyses of Efficacy Parameters 
No hypothesis testing will be performed. The de-escalation effect will be described using 
standard descriptive statistics, but also with model-based estimates for the differences with 95% 
CIs as appropriate. For binary efficacy data, the number and proportion of responders will be 
presented by treatment group. The continuous data and change from baseline will be summarized 
descriptively by treatment group. 
Besides the efficacy analyses specified in the protocol, additional estimands may be defined and 
sensitivity analyses performed for the efficacy assessments. More details on efficacy analyses 
will be described in the SAP. 
9.3.4.1. 
Analysis for Primary Efficacy Endpoint 
9.3.4.1.1. Primary Efficacy Estimand 
The primary estimand for the primary endpoint targets to estimate the effect of decreasing the 
filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 200 mg q.d.on 
corticosteroid-free mMCS remission without ES-confirmed flare or discontinuation of treatment 
at Week 48, regardless of treatment interruptions, in subjects who are in stable clinical remission 
at study entry. The effect size will be estimated using the Mantel-Hanszel method and expressed 
as a difference in proportions.  

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The primary estimand for the primary endpoint is described according to the following attributes: 
Primary Endpoint 
Primary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 200 mg 
q.d. defined through the appropriate inclusion / exclusion criteria. 
Variable 
Binary corticosteroid-free mMCS remission without ES-confirmed 
flare and without discontinuation of treatment at Week 48. 
Corticosteriod-free is defined as free of corticosteroids for at least 
12 weeks. 
Intercurrent events 
including strategy for 
addressing them 
− 
ES-confirmed UC flare: Subjects randomized to the filgotinib 
100 mg q.d. or 200 mg q.d. group will be considered as 
nonresponders for any visit after the re-escalation visit, for 
flares occurring prior to Week 48 (Composite strategy). 
− 
Permanent treatment discontinuation: Subjects who 
discontinue treatment prior to Week 48 will be considered as 
nonresponders in both the 100 mg q.d. and the 200 mg group 
q.d. (Composite strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be included 
as reported in the analysis (Treatment policy strategy). 
Population-level 
summary 
The treatment difference in the percentage of subjects meeting 
corticosteroid-free mMCS remission criteria between the filgotinib 
100 mg q.d. group and 200 mg q.d. group at Week 48.  
Estimator 
The adjusted proportion difference (filgotinib 200 mg – filgotinib 
100 mg) with corresponding 95% CI as calculated by a stratified 
Mantel-Haenszel test (stratification factor: baseline ES [0 or 1]). 
Details on sensitivity analyses for the primary estimand will be described in the SAP. 
9.3.4.1.2. Secondary Efficacy Estimand 
The secondary estimand for the primary endpoint targets to estimate the effect of decreasing the 
filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 200 mg q.d. on 
corticosteroid-free mMCS remission at Week 48, regardless of flare, permanent treatment 
discontinuation, or temporary treatment interruptions, in subjects who are in stable clinical 
remission at study entry. The effect size will be estimated using the Mantel-Hanszel method and 
expressed as a difference in proportions. 

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The secondary estimand for the primary endpoint is described according to the following 
attributes: 
Primary Endpoint 
Secondary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 200 mg 
q.d. defined through the appropriate inclusion / exclusion criteria. 
Variable 
Binary corticosteroid-free mMCS remission at Week 48. 
Intercurrent events 
including strategy for 
addressing them 
− 
ES-confirmed UC flare: Data collected for subjects 
randomized to the filgotinib 100 mg q.d. or 200 mg q.d. group 
for any visit after the re-escalation visit will be included in the 
analyses (Treatment policy strategy). 
− 
Permanent treatment discontinuation: Data collected for 
subjects who discontinue treatment prior to Week 48 will be 
included in the analyses (Treatment policy strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be included 
as reported in the analysis (Treatment policy strategy). 
Population-level 
summary 
The treatment difference in the percentage of subjects meeting 
corticosteroid-free mMCS remission criteria between the filgotinib 
100 mg q.d. group and 200 mg q.d. group. 
Estimator 
The adjusted proportion difference (filgotinib 200 mg – filgotinib 
100 mg) with corresponding 95% CI as calculated by a stratified 
Mantel-Haenszel test (stratification factor: baseline ES [0 or 1]). 
In both the primary and secondary estimands for the primary endpoint, any subjects with missing 
data at Week 48 will primarily be considered as nonresponders. Additional sensitivity analyses 
may be defined in the SAP. 
9.3.4.2. 
Analyses for Secondary Efficacy Endpoints 
9.3.4.2.1. Analyses for Continuous Efficacy Data 
Analyses for endpoints analyzed at Week 48 
The primary estimand for the secondary endpoint that is analyzed at Week 48 (i.e. change from 
baseline in IBDQ) targets to estimate the effect of decreasing the filgotinib dose from 200 mg 
q.d. to 100 mg q.d. versus remaining on 200 mg q.d. in subjects who are in stable clinical 
remission at study entry, regardless of temporary treatment interruptions, under the hypothetical 
condition that no subject had an ES-confirmed UC flare and all subjects remained on treatment. 
The effect size will be estimated using an analysis of covariance and expressed as the mean 
treatment difference. 

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The primary estimand for the secondary endpoint that is analyzed at Week 48 is described 
according to the following attributes: 
Continuous Endpoint 
Primary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as 
randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 
200 mg q.d. defined through the appropriate inclusion / 
exclusion criteria. 
Variable 
Change from baseline in IBDQ at Week 48. 
Intercurrent events including 
strategy for addressing them 
− 
ES-confirmed UC flare: Data collected for subjects 
randomized to the filgotinib 100 mg q.d. or 200 mg q.d. 
group for any visit after the re-escalation visit will be 
considered missing and will be imputed using Last 
Observation Carried Forward (LOCF), if the flare 
occurred prior to Week 48 (Hypothetical strategy). 
− 
Permanent treatment discontinuation: Data collected after 
permanent treatment discontinuation prior to Week 48 
will be considered missing and will be imputed using 
LOCF (Hypothetical strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be 
included as reported in the analysis (Treatment policy 
strategy). 
Population-level summary 
The mean treatment difference between the filgotinib 
100 mg q.d. group and 200 mg q.d. group at Week 48. 
Estimator 
The adjusted mean difference between the 2 treatments 
(filgotinib 200 mg – filgotinib 100 mg) and its corresponding 
95% CI will be estimated using an analysis of covariance 
(ANCOVA) with treatment group and the ES at baseline 
(0 versus 1) as factors and baseline scores as covariate.  
 
The secondary estimand for the secondary endpoint that is analyzed at Week 48 (i.e. change from 
baseline in IBDQ) targets to estimate the effect of decreasing the filgotinib dose from 200 mg 
q.d. to 100 mg q.d. versus remaining on 200 mg q.d. in subjects who are in stable clinical 
remission at study entry, regardless of flare, permanent treatment discontinuation, or temporary 
treatment interruptions. The effect size will be estimated using an analysis of covariance and 
expressed as the mean treatment difference. 

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The secondary estimand for the secondary endpoint that is analyzed at Week 48 is described 
according to the following attributes: 
Continuous Endpoint 
Secondary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as 
randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 
200 mg q.d. defined through the appropriate inclusion / 
exclusion criteria. 
Variable 
Change from baseline in IBDQ at Week 48. 
Intercurrent events including 
strategy for addressing them 
− 
ES-confirmed UC flare: Data collected for subjects 
randomized to the filgotinib 100 mg or 200 mg q.d. 
group for any visit after the re-escalation visit will be 
included in the analyses (Treatment policy strategy). 
− 
Permanent treatment discontinuation: Data collected 
after permanent treatment discontinuation prior to 
Week 48 will be included in the analyses (Treatment 
policy strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be 
included as reported in the analysis (Treatment policy 
strategy). 
Population-level summary 
The mean treatment difference between the filgotinib 
100 mg q.d. group and 200 mg q.d. group at Week 48. 
Estimator 
The adjusted mean difference between the 2 treatments 
(filgotinib 200 mg – filgotinib 100 mg) and its corresponding 
95% CI will be estimated using an analysis of covariance 
(ANCOVA) with treatment group and the ES at baseline 
(0 versus 1) as factors and baseline scores as covariate. 
In both the primary and secondary estimands for the secondary endpoint that is analyzed at 
Week 48, any missing data will be handled using LOCF.  
Analyses for endpoints analyzed over time up to Week 48 
The primary estimand for the secondary endpoints that are measured over time targets to estimate 
the effect of decreasing the filgotinib dose from 200 mg q.d. to 100 mg q.d. versus remaining on 
200 mg q.d. in subjects who are in stable clinical remission at study entry, regardless of 
temporary treatment interruptions, under the hypothetical condition that no subject had an ES-
confirmed UC flare and all subjects remained on treatment. The effect size will be estimated 
using a linear mixed effects model and expressed as the mean treatment difference. 

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The primary estimand for the secondary endpoints that are measured over time is described 
according to the following attributes: 
Continuous Endpoint 
Primary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as 
randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 
200 mg q.d. defined through the appropriate inclusion / 
exclusion criteria. 
Variable 
− 
Change from baseline in CRP up to Week 48. 
− 
Change from baseline in FCP up to Week 48. 
Intercurrent events including 
strategy for addressing them 
− 
ES-confirmed UC flare: Data collected for subjects 
randomized to the filgotinib 100 mg q.d. or 200 mg q.d. 
group for any visit after the re-escalation visit will be 
considered missing, if the flare occured prior to Week 48, 
and will be handled in a linear mixed effects model 
(Hypothetical strategy). 
− 
Permanent treatment discontinuation: Data collected after 
permanent treatment discontinuation prior to Week 48 
will be considered missing and will be handled in a linear 
mixed effects model (Hypothetical strategy). 
− 
Any temporary treatment interruption: Data collected for 
subjects who temporarily interrupt treatment will be 
included as reported in the analysis (Treatment policy 
strategy). 
Population-level summary 
The mean treatment difference between the filgotinib 100 mg 
q.d. group and 200 mg q.d. group at all postbaseline visits up 
to Week 48. 
Estimator 
The adjusted mean difference between the 2 treatments 
(filgotinib 200 mg – filgotinib 100 mg) and its corresponding 
95% CI will be estimated using a linear mixed effects model 
with baseline value, treatment group, the ES at baseline 
(0 versus 1), visit, and treatment group by visit interaction, all 
as fixed effects, and subject as a random effect. 
Details on sensitivity analyses for the primary estimand for the secondary endpoints that are 
measured over time will be described in the SAP. 
The secondary estimand for the secondary endpoints that are measured over time targets to 
estimate the effect of decreasing the filgotinib dose from 200 mg q.d. to 100 mg q.d. versus 
remaining on 200 mg q.d. in subjects who are in stable clinical remission at study entry, 
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The effect size will be estimated using a linear mixed effects model and expressed as the mean 
treatment difference. 
The secondary estimand for the secondary endpoints that are measured over time is described 
according to the following attributes: 
Continuous Endpoint 
Secondary Estimand 
Treatment 
Filgotinib 100 mg q.d. and filgotinib 200 mg q.d. as 
randomized. 
Population 
Subjects who are in stable clinical remission on filgotinib 
200 mg q.d. defined through the appropriate inclusion / 
exclusion criteria. 
Variable 
− 
Change from baseline in CRP up to Week 48. 
− 
Change from baseline in FCP up to Week 48. 
Intercurrent events including 
strategy for addressing them 
− 
ES-confirmed UC flare: Data collected for subjects 
randomized to the filgotinib 100 mg or 200 mg q.d. 
group for any visit after the re-escalation visit will be 
included in the analyses (Treatment policy strategy). 
− 
Permanent treatment discontinuation: Data collected 
after permanent treatment discontinuation prior to 
Week 48 will be included in the analyses (Treatment 
policy strategy). 
− 
Any temporary treatment interruption: Data collected 
for subjects who temporarily interrupt treatment will be 
included as reported in the analysis (Treatment policy 
strategy). 
Population-level summary 
The mean treatment difference between the filgotinib 
100 mg q.d. group and 200 mg q.d. group at all postbaseline 
visits up to Week 48. 
Estimator 
The adjusted mean difference between the 2 treatments 
(filgotinib 200 mg – filgotinib 100 mg) and its 
corresponding 95% CI will be estimated using a linear 
mixed effects model with baseline value, treatment group, 
the ES at baseline (0 versus 1), visit, and treatment group 
by visit interaction all as fixed effects, and subject as a 
random effect.  
In both the primary and secondary estimands for the secondary endpoints that are measured over 
time, any missing data will be handled using a linear mixed effects model where missing values 
are assumed to be missing at random. 

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9.3.4.2.2. Analyses for Time-to-Event Data 
For time-to-event endpoints, the time to occurrence of the first event of interest will be estimated 
in each treatment group using the Kaplan-Meier method. 
The median time-to-event (if reached) will be reported for each treatment group. 
The Cox proportional hazards model, stratified by ES (0 or 1), will be used to estimate outcome 
differences between treatment groups. Hazard ratios and 95% CIs will be provided to quantify the 
treatment difference. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                 
 
 
 
 
  

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9.3.5. 
Analyses of Safety Data 
All safety analyses will be performed using the safety analysis set (Section 9.2.4). All safety data 
will be summarized descriptively by treatment group according to the filgotinib dosing regimen 
actually received at randomization. 
For the primary safety analysis, any data collected after ES-confirmed UC flare will not be 
included in the analyses. 
For the secondary safety analysis, data will be included regardless of flare. 
Additionally, safety data may be analyzed in the subgroup of subjects who are initially assigned 
to 100 mg filgotinib q.d. and are re-escalated later to 200 mg q.d. in the safety analysis set. 
Missing data for safety endpoints will not be imputed. 
Clinical safety will be addressed by assessing AEs, laboratory assessments, physical 
examinations, ECG, and vital signs. 
9.3.5.1. 
Extent of Exposure 
A subject’s extent of exposure to the IP will be generated from the IP administration page of the 
CRF. Exposure data will be summarized by treatment group. Duration of exposure to the IP will 
be expressed as the number of weeks between the first and last dose of IP, inclusive, regardless of 
temporary interruptions in IP administration, and summarized by treatment group. 
9.3.5.2. 
Adverse Events 
Clinical and laboratory AEs will be coded using the Medical Dictionary for Regulatory 
Activities. System Organ Class (SOC), High-Level Group Term, High-Level Term, Preferred 
Term, and Lower-Level Term will be attached to the clinical database. 
The following AEs will be considered as treatment-emergent adverse events (TEAEs): 
Any AE with an onset date on or after the IP start date and no later than 30 days after last dose of 
IP, or any worsening of any AE on or after the IP start date. 
Summaries (number and percentage of subjects) of TEAEs per subject by SOC and Preferred 
Term will be provided by treatment group. TEAEs will also be summarized by causal 
relationship to the IP and severity. In addition, TEAEs leading to treatment interruption or 
permanent discontinuation of the IP will be summarized and listed. Also, all SAEs, including the 
non-treatment-emergent SAEs, will be listed. 
9.3.5.3. 
Clinical Laboratory Evaluations 
Laboratory assessments will be analyzed descriptively. Changes from baseline and shifts 
according to normal ranges and/or a laboratory abnormality grading scale will be presented as 
well. Analyses will be done per treatment group. 

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9.3.5.4. 
Vital Signs 
Vital signs will be analyzed descriptively. Changes from baseline will be presented as well. 
Analyses will be done per treatment group. 
9.3.5.5. 
12-lead Electrocardiogram 
A descriptive analysis will be done for the 12-lead ECG. Summary analyses of abnormalities will 
be presented as well. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
. 
. 
 
 
 
 
 
 
 
 
 
 
 
 
 

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9.3.9. 
Subgroups 
Selected efficacy analyses may be repeated for the subgroups by stratification factor ES 
(0 versus 1). 
Other subgroup analysis can be added to the SAP. 
9.3.10. 
Additional Statistical Considerations 
Not applicable. 
10. 
DATA MONITORING 
10.1. 
Data Monitoring Committee 
In this study subjects will receive the recommended filgotinib dose for UC (approved in EU, UK, 
and Japan) and/or a lower dose, and in case of flare, subjects will be re-escalated to 200 mg 
filgotinib q.d. and addition of corticosteroids can be considered. Subjects will be monitored 
through standard medical and safety monitoring processes. Therefore, no data monitoring 
committee will be installed. 
10.1.1. 
Cardiovascular Safety Endpoint Adjudication Committee 
An independent adjudication committee will be formed to periodically review and adjudicate all 
potential MACE and thromboembolic events in a blinded manner. 
The CVEAC’s specific activities will be governed by a mutually agreed charter, which will 
define the CVEAC’s membership, conduct, and meeting schedule. 
The following events will be adjudicated and classified by the CVEAC: 
− 
cardiovascular death; 
− 
myocardial infarction; 
− 
stroke; 
− 
arterial thromboembolism; 
− 
venous thromboembolism (e.g. deep venous thrombosis, pulmonary embolism). 
Further details will be specified in the CVEAC Charter. 

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11. 
SAFETY REPORTING 
11.1. 
Definitions of Adverse Events, Serious Adverse Events, and 
Special Situations 
11.1.1. 
Adverse Events 
An AE is any untoward medical occurrence, new or worsening of any preexisting condition, in a 
clinical study subject administered a medicinal product and which does not necessarily have to 
have a causal relationship with this treatment. 
An AE can therefore be any unfavorable and unintended sign (e.g. an abnormal laboratory 
finding), symptom, or disease temporally associated with the use of a medicinal product, whether 
or not considered related. AEs may also include pre- or post-treatment complications that occur 
as a result of CSP-specified procedures, worsening of the targeted disease, overdose, drug 
abuse/misuse reports, or occupational exposure. Preexisting conditions that increase in severity or 
change in nature during or as a consequence of participation in the clinical study will also be 
considered AEs. 
11.1.2. 
Serious Adverse Events 
An SAE is defined as an AE that: 
− 
Results in death. 
− 
Is 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). 
− 
Requires in-patient hospitalization or prolongation of existing hospitalization. 
− 
Results in persistent or significant disability/incapacity. 
− 
Is a congenital anomaly / birth defect. 
− 
Is medically significant (medical and scientific judgment should be exercised in deciding 
whether other situations should be considered serious such as important medical events that 
might not be immediately life-threatening or result in death or hospitalization but might 
jeopardize the subject or might require intervention to prevent 1 of the other outcomes listed 
in the definition above). 
11.1.3. 
Unlisted (Unexpected) Adverse Events/ Reference Safety Information 
An AE is considered unlisted if the nature or intensity is not consistent with the applicable 
product reference safety information. For an IP, the expectedness of an AE will be determined by 
whether or not it is listed in the reference safety information part of the IB. 
11.1.4. 
Adverse Events of Special Interest (Immediately Reportable to the 
Sponsor) 
Not applicable. 

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11.1.5. 
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events 
Laboratory abnormalities or other abnormal safety assessments (e.g. ECG, radiography, vital 
signs) without clinical significance based on the investigator’s judgment are not considered AEs 
or SAEs. However, laboratory abnormalities (e.g. clinical chemistry, hematology, and urinalysis) 
or other abnormal (clinical study-specific) assessments (e.g. ECG, radiography, vital signs) that 
require medical or surgical intervention, are associated with signs and/or symptoms, and/or lead 
to IP interruption, modification, or discontinuation must be recorded as an AE or SAE if they 
meet the definition as described in Sections 11.1.1 and 11.1.2, respectively. If the laboratory 
abnormality is part of a syndrome, the syndrome or diagnosis is to be reported (e.g. anemia 
instead of decreased hemoglobin). 
Management of clinical and clinically significant laboratory abnormalities is detailed in 
Appendix 4. 
11.1.6. 
Special Situations 
Special situations are situations that have a possible impact on the safe use of the IP. These 
situations might be or might not be associated with AEs. 
− 
Pregnancy. 
− 
Exposure to IP via breastfeeding. 
− 
Abuse or misuse of IP. 
• 
Abuse of IP is defined as the persistent or sporadic, intentional excessive use of the IP, 
which is accompanied by harmful physical or psychological effects. 
• 
Misuse of IP is defined as a situation where the IP is intentionally and inappropriately 
used not in accordance with the protocol/patient information. 
− 
Drug interaction with IP. 
• 
A drug interaction with IP is defined as any drug/drug, drug/food, or drug/device 
interaction. 
− 
Medication error with IP. 
• 
A medication error with IP is defined as an unintended failure in the drug treatment 
process that leads to, or has the potential to lead to, harm to the subject. 
− 
Overdose with IP. 
An overdose with IP is defined as an accidental or intentional administration of a 
quantity of the IP 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). When applying this definition, clinical 
judgment should always be applied. 
− 
Occupational exposure to IP. 
• 
Occupational exposure to IP is defined as an exposure to the IP as a result of one’s 
professional or nonprofessional occupation. 
− 
Unexpected benefit of IP. 

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• 
Unexpected benefit of IP is defined as an unintended therapeutic effect where the results 
are judged to be desirable and beneficial. 
− 
Transmission of infectious agents via the IP. 
• 
Transmission of infectious agents via the IP is defined as any suspected transmission of 
an infectious agent through the IP. 
− 
Counterfeit or falsified medicine. 
• 
Any IP with a false representation of a) its identity, b) its source, or c) its history. 
− 
Product complaint or quality defect of IP. 
• 
Product complaint or quality defect of IP is defined as complaints or defects of the IP 
arising from potential deviations in the manufacture, packaging, or distribution of the IP. 
11.2. 
Assessment of Adverse Events and Serious Adverse Events 
The investigator is responsible for assessing AEs and SAEs for causality and severity. This is the 
basis for the sponsor’s final review and confirmation of accuracy and completeness of event 
information and causality assessments. 
11.2.1. 
Assessment of Causality 
Investigators should use their knowledge of the subject, the circumstances surrounding the event, 
and an evaluation of any potential alternative causes to determine whether an AE is considered to 
be related to the study drug, indicating "related" or "not related" accordingly. The following 
guidance must be taken into consideration (see also Table 2): 
− 
Temporal relationship of event onset to the initiation of study drug. 
− 
Course of the event, with special consideration of the effects of dose reduction, 
discontinuation of study drug, or reintroduction of study drug (as applicable). 
− 
Known association of the event with the study drug or with similar treatments. 
− 
Known association of the event with the disease under study. 
− 
Presence of risk factors in the subject or use of concomitant medications known to increase 
the occurrence of the event. 
− 
Presence of non-treatment-related factors that are known to be associated with the 
occurrence of the event. 

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Table 2: 
Causal Attribution Guidance 
Is the adverse event suspected to be caused by the study drug on the basis of facts, evidence, science-
based rationales, and clinical judgment? 
Related 
There is a plausible temporal relationship between the onset of the adverse event and 
administration of the study drug, and the adverse event cannot be readily explained by the 
patient's clinical state, intercurrent illness, or concomitant therapies; and/or the adverse 
event follows a known pattern of response to the study drug; and/or the adverse event abates 
or resolves upon discontinuation of the study drug or dose reduction and, if applicable, 
reappears upon re-challenge. 
Not 
related 
An adverse event will be considered related, unless it fulfills the criteria specified below. 
Evidence exists that the adverse event has an etiology other than the study drug 
(e.g. preexisting medical condition, underlying disease, intercurrent illness, or concomitant 
medication); and/or the adverse event has no plausible temporal relationship to 
administration of the study drug (e.g. cancer diagnosed 2 days after first dose of study drug). 
 
It should be emphasized that ineffective treatment should not be considered as causally related in 
the context of AE reporting. 
11.2.2. 
Assessment of Severity 
The severity of AEs must be graded using the Common Terminology Criteria for Adverse Events 
(CTCAE) version 5.0. If a CTCAE criterion does not exist, the investigator must use the grade or 
adjectives: Grade 1 (mild), Grade 2 (moderate), Grade 3 (severe), Grade 4 (life-threatening), or 
Grade 5 (fatal) to describe the maximum intensity of the AE. For purposes of consistency with 
the CTCAE, these intensity grades are defined in Table 3. 
Table 3: 
Grading of AE 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 ADLa  
Grade 3  
Severe 
Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling; 
limiting self-care ADLb  
Grade 4  
Life-threatening 
Urgent intervention indicated  
Grade 5  
Death 
Death-related AE  
ADL = Activities of Daily Living. 
a Instrumental ADL refers to preparing meals, shopping for groceries or clothes, using the telephone, managing money, etc. 
b Self-care ADL refers to bathing, dressing, and undressing, feeding self, using the toilet, taking medications, and not bedridden. 

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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. 
Management of clinical and clinically significant laboratory abnormalities is detailed in 
Appendix 4. This is upon the investigator’s assessment. 
If there is a worsening of an AE, it must be recorded. 
11.3. 
Instructions for Reporting Adverse Events, Serious Adverse 
Events, Pregnancies, and Other Special Situations 
11.3.1. 
Adverse Events 
The AE reporting period for safety surveillance begins when the subject signs the ICF and ends at 
the subject’s last scheduled visit. In this period, all new AEs, regardless of cause or relationship, 
derived by spontaneous, unsolicited reports of subjects, by observation, and by routine open 
questioning (such as “How do you feel?”) need to be recorded in the source and in the CRF. 
In case an AE is ongoing at the time of the last follow-up visit, the investigator needs to 
follow-up on the subject until AE resolution or reasonable stabilization and to document in the 
subject’s source documentation. No related updates or additional data on the AE should be 
reported in the CRF. 
If a subject is documented as lost to follow-up, ongoing/unknown outcome AEs will not be 
followed-up. 
If the AE meets the criteria for seriousness, the SAE must be reported as indicated in 
Section 11.3.2. 
11.3.2. 
Serious Adverse Events 
Subjects experiencing an SAE or an emergency situation will be examined by a physician as soon 
as possible. The subject will remain under observation as long as medically indicated. 
Appropriate additional examinations will be performed until all parameters return to normal or 
are otherwise explained or stable. 
All SAEs, whether or not deemed IP-related, must be recorded in the eCRF database and from 
there transmitted to the sponsor. The investigator must report each SAE immediately, and under 
no circumstances should this exceed 24 hours following the knowledge of the SAE, as indicated 
on page 2 under “Emergency Contact Information”. 
If for any reason it is not possible to record SAE information electronically, i.e. the eCRF 
database is not functioning, record the SAE on a SAE form and submit the SAE within 24 hours 
by e-mail to: 
 
Every SAE reported via form must be transcribed into the eCRF database as soon as possible 
according to instructions in the eCRF completion guidelines. 

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The SAE reporting must at least contain identifiers of the subject and the reporter, SAE term and 
statement of relatedness to the IP, and at a later stage if not yet available within 24 hours, the 
form needs to be completed with a clearly written narrative describing signs, symptoms, and 
treatment of the event, diagnostic procedures, as well as any relevant laboratory data and any 
sequelae. 
Follow-up and outcomes must be reported and documented in the source documents for all 
subjects that experience an SAE.  
Copies of additional laboratory tests, consultation reports, post-mortem reports, hospital case 
reports, autopsy reports, and other documents must be sent when requested and available. Only 
subject identifiers (subject number) should appear on the copies, and all names and initials must 
be blackened and rendered illegible. Follow-up reports relative to the subject’s subsequent course 
must be submitted until the event has subsided or, in case of permanent impairment, until the 
condition stabilizes. 
Any SAEs that occur after the post-treatment follow-up visit but within 30 days of the last dose 
of IP(s), regardless of causality, should also be reported (Emergency Contact Information on 
page 2) but not entered in the source. Investigators are not obligated to actively seek SAEs after 
the CSP-defined follow-up period. However, if the investigator is informed about an SAE that 
occurs at any time after the subjects’ post-treatment follow-up visit and the event is deemed 
relevant to the use of IP(s), he/she must promptly document and report the event to the sponsor 
by using the SAE form. 
11.3.3. 
Pregnancy 
All initial reports of pregnancy in female subjects included in the clinical study must be recorded 
and documented in the source documents and on the pregnancy form. The investigator must 
report each pregnancy immediately, and under no circumstances should this exceed 24 hours 
following the knowledge of the pregnancy, as indicated on page 2 under “Emergency Contact 
Information”.  
All pregnancies should be followed-up until delivery or pregnancy interruption. The investigator 
will contact the subject after acquiring consent, at the expected time of delivery for follow-up and 
for information regarding the outcome of the newborn. Abnormal pregnancy and/or abnormal 
newborn outcomes are considered SAEs and must be reported using the SAE form. 
11.3.4. 
Reporting of Special Situations (Other Than Pregnancy) With or Without 
Associated Adverse Events 
In case a special situation is not associated with an AE, the special situation must be reported 
within 24 hours by using the Special Situations form as indicated on page 2 under “Emergency 
Contact Information”. 
In case a special situation is associated with an AE, the special situation must be reported within 
24 hours by using the Special Situations form and the associated AE must be reported as 
specified in Section 11.3.1. 

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In case a special situation is associated with an SAE, the special situation must be reported within 
24 hours by using the SAE form (and not the Special Situations form) and the associated SAE 
must be reported as specified in Section 11.3.2. 
11.4. 
Sponsor Reporting Requirements 
Depending on relevant local legislation or regulations the sponsor may be required to expedite to 
worldwide regulatory agencies reports of SAEs and serious adverse drug reactions or SUSARs. 
The sponsor or a specified designee will notify worldwide regulatory authorities and the relevant 
IEC/IRB in concerned Member States of applicable SUSARs as outlined in current regulations. 
Assessment of expectedness for SAEs will be determined using the reference safety information 
section in the IB or relevant local label as applicable. 
All concerned investigators will receive a safety letter notifying them of relevant SUSAR reports 
associated with any IP(s). The investigator must notify the IEC/IRB of SUSAR reports as soon as 
is practical, where this is required by local regulatory authorities, and in accordance with the local 
institutional policy. 
12. 
SPONSOR’S AND INVESTIGATOR’S RESPONSIBILITIES 
This clinical study will be conducted in compliance with this CSP, the current ICH Guideline E6 
“Good Clinical Practice (GCP)”, and applicable local ethical and legal requirements. 
Good Clinical Practice is an international ethical and scientific quality standard for designing, 
conducting, recording, and reporting studies that involve the participation of human subjects. 
Compliance with this standard provides public assurance that the rights, safety, and well-being of 
clinical study subjects are protected, consistent with the principles that have their origin in the 
Declaration of Helsinki (1996 and successive amendments), and that the clinical study data are 
credible. 
The contact details of each third party vendor involved in the conduct of the clinical trial will be 
available in the investigator’s (as appropriate) and sponsor’s files. 
12.1. 
Sponsor’s Responsibilities 
12.1.1. 
Regulatory Authority Approval 
Prior to clinical study start, this CSP together with all relevant documentation needs to be 
submitted to the respective regulatory authorities for review and approval in compliance with 
current regulations before the study can start. 
12.1.2. 
Clinical Study Closure Considerations 
The sponsor reserves the right to close the site or end the clinical study at any time for any 
reason. In case of an early termination of the clinical study, i.e. premature end of the study for 
any reason before the conditions specified in the protocol are complied with, or temporary halt by 

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the sponsor, the IEC/IRB, and regulatory authorities will be notified according to local 
requirements, unless more strict requirements are specified by IEC/IRB and/or regulatory 
authorities. The notification will include a detailed written explanation of the reasons for the 
termination/halt. 
Reasons for the closure of a site may include, but are not limited to: 
− 
successful completion of the clinical study at the site; 
− 
the overall required number of subjects for the clinical study has been recruited; 
− 
failure of the investigator to comply with the CSP, ICH-GCP guidelines, or local 
requirements; 
− 
inadequate recruitment of subjects by the investigator. 
Reasons for early termination of a clinical study by the sponsor may include, but are not limited 
to: 
− 
safety concerns; 
− 
sufficient data suggesting lack of efficacy. 
The end of clinical study declaration will be submitted to the regulatory authorities and IEC/IRB 
after the complete clinical study has ended in all participating sites, in all countries. This 
notification will also be submitted according to local requirements of the end of the clinical study 
in a given country/member state. 
12.1.3. 
Indemnification 
Under the conditions of a contract concluded between investigator, site, and sponsor or designee, 
which shall prevail, the sponsor shall, except in case of gross negligence or willful misconduct, 
indemnify and hold harmless the investigator and his/her medical staff from any claim arising 
from the clinical study activities carried out in compliance with the CSP, sponsor’s instructions, 
and applicable local regulations. 
The investigator must notify the sponsor immediately upon notice of any claims or lawsuits. 
12.1.4. 
Insurance 
The sponsor shall maintain insurance coverage that is sufficient to cover its obligations and that 
is consistent with human clinical study local regulations. Provided that the subject has been 
treated according to the CSP and sponsor’s instructions, any injury caused to a subject, which is 
the direct result of his/her participation to the clinical study shall be covered by the sponsor’s 
insurance, except in case of gross negligence or willful misconduct by the investigator. 
12.1.5. 
Archiving 
The sponsor will archive the content of the trial master file (TMF) for at least 25 years after the 
end of the clinical study. 

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12.2. 
Reporting 
Where required by IEC/IRB per local requirements, at least once a year, the investigator will 
provide the IEC/IRB with a progress report to allow review of the clinical study (see 
Section 12.7.1). 
The results of the unblinded Week 48 interim analyses (primary, secondary, and exploratory 
efficacy endpoint results up to Week 48 and safety up to the data cut-off date) will be reported by 
the sponsor in an interim clinical study report. At the global end of the clinical study, the final 
results of the clinical study will be reported in a final clinical study report by the sponsor. A 
summary or full report, depending on the requirements, will be provided by the sponsor to the 
investigators, to the relevant regulatory authorities, and IECs/IRBs (if required by the applicable 
regulatory requirements) within 1 year after the end of the clinical study.  
12.3. 
Publication 
It is understood by the investigator that the sponsor shall be free to use the compound-related 
information, which is generated during the clinical study and may disclose it to other clinical 
investigators and to regulatory agencies. As a consequence, the investigator agrees to provide all 
clinical study results and data generated during this clinical study to the sponsor. 
The investigator shall not be authorized to submit the results of this clinical study and any data 
for public disclosure (e.g. publication or presentation) without the prior written approval of the 
sponsor, which shall not be unreasonably withheld. 
However, it is understood and agreed by the investigators that their results and/or findings shall 
not be authorized for publication prior to sponsor’s publication of the overall clinical study 
results. The investigator agrees that prior to the publication of any results, he/she shall provide 
the sponsor with a draft copy of the intended publication. The sponsor shall have the right to 
review it and to make any comments. In accordance with generally accepted scientific 
collaboration principles, co-authorship with any staff member sponsor involved in the clinical 
study, will be discussed and mutually agreed upon before submission of any manuscript to a 
publisher. 
12.4. 
Investigator’s Responsibilities 
12.4.1. 
Financial Disclosure 
The disclosed financial interest of any (sub-)investigator participating in this study must be 
collected before the investigator is permitted to begin participation in the study. The investigator 
is required to promptly update this information if any relevant changes occur during the course of 
the study and for 1 year following the completion of the study. 
Any (sub)-investigator participating in the study must complete the Financial Disclosure Form 
prior to site activation. 

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12.4.2. 
Source Data and Data Capture 
The nature and location of all source documents need to be identified and documented to ensure 
that all sources of original data required to complete the CRF are known and are accessible for 
verification by the monitor. 
Data transferred from third partners (e.g. laboratory data) may be directly captured as source data. 
The CRF completion guidelines will be provided to each site. 
It is required that the author of an entry in the source documents is identifiable. Following ICH-
GCP guidelines, direct access to sponsor’s representatives to source documents must be granted 
for the purpose of verifying that the data recorded on the CRF are consistent with the original 
source data. 
12.4.3. 
Archiving 
Unless local legislation requires archiving for a longer period, the investigator shall archive the 
content of the clinical investigator site file for at least 25 years after the end of the clinical study. 
However, the medical files of subjects shall be archived in accordance with national law. 
The investigator should take measures to prevent accidental or premature destruction of these 
documents. 
Under no circumstance shall the investigator relocate or dispose any clinical study documents 
before having obtained a written approval of the sponsor. 
If it becomes necessary for the sponsor or the appropriate regulatory authority to review any 
documentation relating to this clinical study, the investigator must permit access to such reports. 
The subject is granting access to his/her source data by signing the ICF. 
Any difficulty in storing original documents must be discussed with the monitor prior to the 
initiation of the clinical study. 
12.4.4. 
Participation Cards 
If the subjects are not under 24-hour supervision of the investigator or site staff, they must be 
provided with a subject participation card indicating the investigator’s name, and the site’s 
24-hour emergency contact number. The subjects should be advised to keep the participation card 
with them at all times. 
12.5. 
Confidentiality 
The subject will receive all information as required by the EU General Data Protection 
Regulation (i.e. the identity and contact details of the controller, the contact details of the data 
protection officer, the clinical research purposes, the legal basis for the processing, the recipients 
of the personal data, the transfer of the personal data to third countries and respective safeguards, 
the retention periods, the fair processing of his data, and all his/her data subject’s rights) or by 
any other (locally) applicable requirements and/or regulations. All details are listed in the ICF. 

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All information concerning the product and the sponsor’s operations (such as patent applications, 
formulae, manufacturing processes, basic scientific data, or formulation information supplied to 
the investigator by the sponsor and not previously published) is considered confidential and must 
not be disclosed by the investigator to any third party without the sponsor’s prior written 
approval. The investigator agrees to use this information only in accomplishing the clinical study 
and will not use it for other purposes. 
In order to permit easy identification of the individual subject during and after the clinical study, 
the investigator is responsible for keeping an updated Subject Identification Code List. The 
monitor will review this document for completeness. However, the investigator must guarantee 
the subject’s anonymity will be maintained. Therefore, in order to ensure subject confidentiality, 
the Subject Identification Code List must remain at the site and no copy will be made. 
12.6. 
Protection of Personal Data 
The subject will receive all information as required by the EU General Data Protection 
Regulation (i.e. the identity and contact details of the controller, the contact details of the data 
protection officer, the clinical research purposes, the legal basis for the processing, the recipients 
of the personal data, the transfer of the personal data to third countries and respective safeguards, 
the retention periods, the fair processing of his data, and all his/her data subject’s rights) and/ or 
by any other (locally) applicable requirements and/or regulations. All required information is 
listed in the ICF. 
The sponsor is considered as a controller in respect to the personal data of the study subjects that 
are collected in connection with the study, and shall act in accordance with the relevant data 
protection laws in relation to the collection and processing of that personal data. The personal 
data of the subjects will be pseudonymized as indicated above (see Section 12.5), making sure 
that the identity of the subjects is not disclosed. Personal data such as health status, year of birth, 
age, and demographics (sex, race, and ethnicity) will be collected. Samples for safety analysis 
may include subject number, panel number, sex, year of birth. Samples collected for bioanalysis 
will contain either subject number or panel number. All other personal data will be kept at the 
site. The study subject’s personal data shall be collected and processed for the purposes (and the 
corresponding legal bases) as described in the ICF. The study subjects’ personal data might be 
processed for such purposes by other parties including: the sponsor’s affiliates and licensing 
partners, its business partners, processors, regulatory agencies and other health authorities, and 
IECs. The study subjects’ data may also be further de-identified and added to research databases 
and used in the future by the sponsor and its affiliates for certain additional statistical, clinical 
research purposes. 
Personal data is securely protected to prevent accidental or unlawful destruction, unauthorized 
access, disclosure, alteration, or loss of the personal data. Access to personal data is restricted so 
that only staff members who are required to access personal data as part of their job role can do 
so. All staff members who access personal data are bound by a duty of confidentiality. 
Technical requirements for the electronic storage and use of data by the sponsor and vendor are 
as follows:  

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− 
All personal data is pseudonomized by assigning a code to the subject, which replaces his or 
her name. 
− 
All personal data is stored on password-protected computers. 
− 
Computers storing electronic personal data are protected by antivirus software and the 
network on which computers are linked is protected by industry-grade firewalls. 
− 
Off-site staff members can only access networked computers through a virtual private 
network (VPN). 
− 
Electronic access to data is limited according to users’ roles and tracked (Privileged Access 
Management). 
− 
Regular audits of certain applications and systems. 
− 
Incident management system and patch management is in place. 
− 
All data is backed up regularly and stored in a protected location. 
− 
Regular inspections of emergency equipments. 
− 
Encryption of the computer, firewalls, and anti-malware software(s). 
 
Organizational arrangements are as follows:  
− 
The premises are secured by key-card access. 
− 
Data Protection Policies Framework is adopted (Global Internal Data Protection Policy, ICF 
including a Privacy Statement, Privacy Statement toward Staff Members and External 
Contractors, Electronic Communication Policy; etc.). 
− 
Data Protection Procedures are in place (Data Subject Rights Procedures, Maintenance of 
Record of Processing Activities Procedure, etc.). 
− 
Homeworking Policy and Password Policy. 
− 
Physical files containing personal data are stored within locked cabinets that can only be 
accessed by authorized personnel. 
− 
Sponsor due diligence and assessment of third parties is accomplished via a Vendor Risk 
Assessment process before entering into any contractual relationship. 
− 
Data security and/or confidentiality provisions are included in Data Processing Agreements 
and Data Sharing Agreements with pre-assessed third parties. 
− 
Documented back-up and disaster recovery procedures are in place. 
− 
Internal audit and compliance functions of the sponsor provide regulatory oversight. 
− 
Additionally, the sponsor’s staff members - contractually bound by a duty of confidentiality - 
receive regular awareness training in this matter. 
Concerning Personal Data Security Breach Management, the sponsor has a comprehensive 
process in place for identifying, assessing, resolving, and reporting any potential personal data 
breach. All staff are trained in the identification of potential personal breaches. Potential breaches 
are managed by appropriately trained personnel in accordance with SOPs. After robust 
assessment, data breaches deemed serious will be reported to the supervisory authority not later 
than 72 hours and/or to study subjects without undue delay after having become aware of it. 

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12.7. 
Ethical Considerations 
12.7.1. 
Independent Ethics Committee / Institutional Review Board 
This clinical study can only be undertaken after IEC/IRB approval of this CSP together with all 
relevant documentation. This approval document must be dated and clearly identify the clinical 
study and the related clinical study documents being approved, including the subject 
compensation programs, if applicable. 
During the course of the clinical study, at least the following documents have to be submitted to 
the IEC/IRB, per local requirements: 
− 
changes to the IB; 
− 
reports of AEs that are serious, unlisted, and associated with the IP (in compliance with 
IEC/IRB, per local requirements); 
− 
CSP amendments; 
− 
ICF amendments. 
 
The IEC/IRB is responsible for continuous review of the clinical study. Where required by 
IEC/IRB, per local requirements, at least once a year the investigator will provide the IEC/IRB 
with a progress report to allow review of the clinical study. Additional progress reports should be 
provided according to local legal requirements. These requests and (re-)approvals, if applicable, 
should be documented in writing. 
12.7.2. 
Informed Consent 
The investigator or designated personnel must explain the clinical study and the implications of 
participation (e.g. objectives, methods, anticipated benefits, possible risks) to potential subjects 
according to applicable regulations prior to any clinical study-related activity. Subjects will be 
informed that their participation is voluntary and that they may withdraw from the clinical study 
at any time. They will be informed that choosing not to participate or to withdraw from the 
clinical study will not have an impact on the care the subject will receive for the treatment of 
their disease. 
The subject will be given sufficient time to read the ICF and to ask additional questions. After 
this explanation and before entry in the clinical study, the subject’s consent must be appropriately 
recorded by means of the subject’s personally dated signature and by the dated signature of the 
investigator or their authorized delegate. After having obtained the consent, a copy of the signed 
and dated ICF must be given to the subject. 
If new information becomes available relevant to the subject’s willingness to participate in the 
clinical study, the subject will be informed in a timely manner by means of an amended ICF. This 
amended ICF will be signed and dated by the subject and the investigator to document the 
willingness of the subject to continue with the clinical study. 

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This signed and dated amended version will be filed together with the initially signed and dated 
ICF. 
 
 
 
 
 
 
 
 
12.8. 
Data Quality Control/Assurance 
12.8.1. 
Monitoring 
Data quality will be assured through monitoring, medical monitoring, and other relevant activities 
as described in the study plans available in the TMF. This clinical study will be monitored by 
sponsor representatives according to their current SOPs. 
To guarantee adequate protection of the subjects and to guarantee the quality of the data, the 
sponsor will ensure oversight of any clinical study-related duties and functions carried out on its 
behalf, including clinical study-related duties and functions that are subcontracted to another 
party by the sponsor’s contracted CRO(s). 
A Risk Management process is in place that includes risk identification, risk analysis, risk 
evaluation, risk control, risk communication, risk review, and risk reporting. A Risk Management 
Tool is prepared for the study that evaluates potential risks and defines Quality Tolerance Limits 
in relation to rights, safety, and well-being of the study subjects as well as the data quality. Risks 
are considered at study level (e.g. personnel, vendors, IP, study design, data collection, and 
recording). 
12.8.2. 
Audit and Inspection 
To ensure compliance with relevant regulations, an independent quality assurance representative, 
regulatory authorities, and/or IECs/IRBs may review this clinical study. This implies that 
auditors/inspectors will have the right to inspect the site(s) at any time during and/or after 
completion of the clinical study and will have access to the data generated during the clinical 
study, source documents, and subject’s files. By participating in this clinical study, investigators 
agree to this requirement. 
 

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13. 
REFERENCES 
Dragoni, G., Innocenti, T., & Galli, A. (2021). Biomarkers of Inflammation in Inflammatory 
Bowel Disease: How Long before Abandoning Single-Marker Approaches? Digestive 
Diseases, 39(3), 190–203. https://doi.org/10.1159/000511641. 
Li, M., Lan, L., Zhang, S., Xu, Y., He, W., Xiang, D., Liu, D., Ren, X., & Zhang, C. (2021). 
IL-6 downregulates hepatic carboxylesterases via NF-κB activation in dextran sulfate sodium-
induced colitis. International Immunopharmacology, 99, 107920. 
https://doi.org/10.1016/j.intimp.2021.107920. 
Shen, Y., Shi, Z., & Yan, B. (2019). Carboxylesterases: Pharmacological Inhibition Regulated 
Expression and Transcriptional Involvement of Nuclear Receptors and other Transcription 
Factors. Nuclear Receptor Research, 6, 101435. doi:10.32527/2019/101435. 
World Health Organization (WHO). (1994). Requirements for the collection, processing and 
quality control of blood, components and plasma derivatives. WHO Technical Report Series, 
No 840. Available at: https://www.who.int/publications/m/item/annex2-who-trs-840. 
 
 
 

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14. 
APPENDICES 
 
 
 
 
 

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Appendix 2: Mayo Scoring System for Assessment of Ulcerative Colitis Activity 
 
Stool Frequency–Each subject serves 
as his or her own control to establish 
the degree of abnormality of the stool 
frequency  
 0  
Normal number of stools for subject  
 1  
1 to 2 stools per day more than normal  
 2  
3 to 4 stools more than normal  
 3 
≥5 stools more than normal 
Rectal Bleeding–The daily bleeding 
score represents the most severe 
bleeding of the day  
 0  
No blood seen  
 1  
Streaks of blood with stool less than half the time  
 2  
Obvious blood with stool half or more than half of the 
 
time  
 3  
Blood alone passes 
Endoscopic findings–Assessed by 
local reader (include only for MCS 
assessment) 
 0  
Normal or inactive disease  
 1  
Mild disease (erythema, decreased vascular pattern)  
 2  
Moderate disease (marked erythema, lack of vascular 
 
pattern, friability, erosions)  
 3  
Severe disease (spontaneous bleeding, ulceration) 
Physician’s Global Assessment–The 
physician’s global assessment 
acknowledges the 3 other criteria, the 
subject’s daily recollection of 
abdominal discomfort and general 
sense of well-being, and other 
observation, such as physical findings 
and the subject’s performance status 
 0  
Normal  
 1  
Mild disease  
 2  
Moderate disease  
 3  
Severe disease 
 
 
 

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Appendix 3: Clinical Laboratory Assessments 
Hematology  
Chemistry 
Urinalysis 
Other 
Hematocrit 
Hemoglobin 
Platelet count 
Red blood cell (RBC) 
count 
White blood cell 
(WBC) count 
Differentials (absolute 
and percentage), 
including: 
Lymphocytes 
Monocytes 
Neutrophils 
Eosinophils 
Basophils 
Reticulocyte count 
Mean corpuscular 
volume (MCV) 
Alkaline phosphatase 
Aspartate aminotransferase 
(AST) 
Alanine aminotransferase 
(ALT) 
Total bilirubin 
Direct and indirect bilirubin 
Total protein 
Albumin 
Bicarbonate 
Blood urea nitrogen 
Calcium 
Chloride 
Serum creatinine 
Creatinine clearance (CrCl) 
Cockcroft-Gault formula 
Glucose 
Phosphorus 
Magnesium 
Potassium 
Sodium 
Creatine phosphokinase (CPK) 
Appearance: 
Blood 
Color 
Glucose 
Leukocyte esterase 
pH 
Protein 
Urobilinogen 
 
C-reactive protein (CRP) 
Fecal (stool) 
Calprotectin 
Bacterial stool culture 
Clostridium difficile 
toxin 
Ova and parasites 
Serum biomarkers 
Serum immunoglobulins 
QuantiFERON® (or 
centrally reported 
equivalent assay) 
Prothrombin time (PT) 
Partial Thromboplastin 
time (PTT) 
International Normalized 
Ratio (INR)  
HBV DNA 
Pregnancy 
In females of 
childbearing potential: 
Serum pregnancy  
Urine pregnancy  
In postmenopausal 
females: 
Serum FSH test at 
screening 
Lipids (fasted) 
Triglycerides 
Cholesterol and its subfractions 
(high-density lipoprotein [HDL]
and low-density lipoprotein 
[LDL]) 
  
 
 
 
 

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Appendix 4: Management of Clinical and Laboratory Adverse Events 
 
 
 
 
 
 
 
 
Grade 1 
Grade 2 
Grade 3 
Grade 4 
May continue 
dosing at the 
discretion of the 
investigator 
Repeat lab to 
confirm toxicity 
grade 
Repeat lab to 
confirm toxicity 
grade 
If confirmed and 
possibly or probably 
related to IP, 
discontinue IP dosing 
permanently and 
follow at periodic 
intervals at least 
weekly until a return 
to baseline or is 
otherwise explained 
If confirmed and possibly and/or probably 
related to IP:  
1. Withhold IP until <= Grade 2 
2. Restart all IP at full dose 
If confirmed and unrelated to IP, 
dosing may continue at the 
discretion of the investigator 
If Grade 3 or 4 recurrence that is confirmed 
and possibly or probably related to IP, 
discontinue all IP dosing permanently 
If Grade 3 or 4 recurrence that is considered 
unrelated to IP, continue all IP at the same dose at 
the discretion of the investigator 

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SIGNATURE PAGE – SPONSOR 
Study Title: 
A randomized, double-blind, controlled, multi-center study to evaluate the 
efficacy and safety of dose de-escalation of orally administered filgotinib in 
subjects with ulcerative colitis in clinical remission 
CSP Version: 
2.0 
Date: 
17-Mar-2023 
Amendment: 
1 
 
 
 
This CSP has been reviewed and approved by the sponsor to ensure compliance with this CSP, 
the current ICH-GCP Guideline E6, and applicable local ethical and legal requirements. 
 
 
 
 An electronic signature for the sponsor is provided 
at the end of the document. 
Medical Leader 
 Signature 
 Date 
 
 
 

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SIGNATURE PAGE – INVESTIGATOR 
Study Title: 
A randomized, double-blind, controlled, multi-center study to evaluate the 
efficacy and safety of dose de-escalation of orally administered filgotinib in 
subjects with ulcerative colitis in clinical remission 
CSP Version: 
2.0 
Date: 
17-Mar 2023 
Amendment: 
1 
 
 
 
I, the undersigned, have read this CSP and will conduct the study as described in compliance with 
this CSP, the current ICH-GCP Guideline E6, and applicable local ethical and legal requirements. 
 
 
 
  
  
Investigator Name 
 Signature 
 Date 
 

Signature Page for glpg0634-cl-341-protocol-amend1 20975
Signature Page for glpg0634-cl-341-protocol-amend143952_37012_115917
Approval
Associate Medical Director
Clinical Development
21-Mar-2023 11:28:17 GMT+0000