A Long-Term Extension Study to Evaluate the Safety of Filgotinib in Subjects With Crohn's Disease
Phase: PHASE3
Conditions: Crohn's Disease
Sponsor: Galapagos NV

Galapagos 
CONFIDENTIAL 
43952_40834_108642 
GS-US-419-3896 (GLPG0634-CL-310) 
 
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CLINICAL STUDY PROTOCOL 
 
 
Study Title: 
A Long-Term Extension Study to Evaluate the Safety of 
Filgotinib in Subjects with Crohn’s Disease 
 
 
Sponsor: 
Galapagos NV 
Generaal De Wittelaan L11 A3 
2800 Mechelen, Belgium 
 
 
IND Number: 
EudraCT Number: 
Clinical Trials.gov 
Identifier: 
129646 
2016-002763-34 
 
NCT02914600 
 
 
Indication: 
Crohn’s Disease 
 
 
Protocol ID: 
GS-US-419-3896 
Galapagos Medical Leader: 
Name: 
 
 
 
Protocol Version/Date: 
Original: 
 
15 July 2016  
Amendment 1: 
 
07 September 2016 
Amendment 2: 
 
11 November 2016 
Amendment 3: 
 
15 June 2017 
Amendment 4: 
 
09 March 2018 
Amendment 5: 
 
09 November 2018 
Amendment 5.1*:  
17 April 2019 
*Canada, Israel, France, UK, US, and VHP countries only 
Amendment 6:  
 
05 September 2019 
Amendment 7:  
 
23 March 2020 
Amendment 8:  
 
02 December 2021 
Amendment 9:  
 
23 November 2022 
 
 
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. 
 

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5. 
INVESTIGATIONAL MEDICINAL PRODUCTS ............................................................. 38 
5.1. 
Randomization, Blinding and Treatment Codes ................................................. 38 
5.1.1. 
Blinding .............................................................................................. 38 
5.2. 
Description and Handling of Filgotinib and Placebo to Match (PTM) .................. 39 
5.2.1. 
Formulation ........................................................................................ 39 
5.2.2. 
Packaging and Labeling ..................................................................... 39 
5.2.3. 
Storage and Handling ......................................................................... 39 
5.3. 
Dosage and Administration ................................................................................ 40 
5.4. 
Prior and Concomitant Medications ................................................................... 40 
5.4.1. 
Allowed Concomitant Medications ...................................................... 40 
5.4.2. 
Prohibited Concomitant Medications ................................................... 41 
5.5. 
Vaccine Guidelines ............................................................................................ 42 
5.6. 
Accountability for Study Drug............................................................................. 42 
5.6.1. 
Investigational Medicinal Product Return or Disposal ......................... 42 
6. 
STUDY PROCEDURES ................................................................................................ 43 
6.1. 
Subject Enrollment and Treatment Assignment ................................................. 43 
6.2. 
Pretreatment Assessments ................................................................................ 43 
6.2.1. 
Day 1 Visit .......................................................................................... 43 
6.3. 
Treatment Assessments .................................................................................... 46 
6.3.1. 
Week 2 and Week 4 (± 3 days) ........................................................... 46 
6.3.2. 
Every 4 Weeks From Day 1 (± 7 days) ............................................... 46 
6.3.3. 
Week 12 and Then Every 12 Weeks Thereafter From Day 1 
(± 7 days) ........................................................................................... 47 
6.3.4. 
Every 24 Weeks From Day 1 (± 7 days) ............................................. 47 
6.3.5. 
Every 48 Weeks From Day 1 (± 7 days) ............................................. 48 
6.3.6. 
End of Treatment Visit ........................................................................ 48 
6.4. 
Safety ................................................................................................................ 48 
6.4.1. 
Thromboembolic Events ..................................................................... 48 
6.5. 
Post-Treatment Assessments (± 3 days) ........................................................... 48 
6.6. 
Early Termination Assessments ........................................................................ 49 
6.7. 
Assessments After Study Unblinding ................................................................. 49 
6.8. 
End of Study ...................................................................................................... 50 
6.9. 
Post Study Care ................................................................................................ 50 
6.10. 
Clinical Laboratory Assessments ....................................................................... 50 
7. 
ADVERSE EVENTS AND TOXICITY MANAGEMENT .................................................. 50 
7.1. 
Definitions of Adverse Events, Adverse Reactions, and 
Serious Adverse Events .................................................................................... 50 
7.1.1. 
Adverse Events .................................................................................. 50 
7.1.2. 
Serious Adverse Events ..................................................................... 51 
7.2. 
Assessment of Adverse Events and Serious Adverse Events ............................ 51 
7.2.1. 
Assessment of Causality for Study Drugs and Procedures ................. 51 
7.2.2. 
Assessment of Severity ...................................................................... 52 
7.3. 
Investigator Requirements and Instructions for Reporting Adverse Events 
and Serious Adverse Events to the Sponsor ...................................................... 52 
7.3.1. 
Adverse Events .................................................................................. 53 
7.3.2. 
Serious Adverse Events ..................................................................... 53 
7.4. 
Sponsor Reporting Requirements ...................................................................... 54 
7.5. 
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events and Serious Adverse Events .................................................... 55 

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7.6. 
Toxicity Management ........................................................................................ 55 
7.6.1. 
Grades 1 and 2 Laboratory Abnormality or Clinical Event ................... 55 
7.6.2. 
Grade 3 Laboratory Abnormality or Clinical Event .............................. 55 
7.6.3. 
Grade 4 Laboratory Abnormality or Clinical Event .............................. 56 
7.7. 
Special Situations Reports ................................................................................. 56 
7.7.1. 
Definitions of Special Situations .......................................................... 56 
7.7.2. 
Instructions for Reporting Special Situations ....................................... 57 
8. 
STATISTICAL CONSIDERATIONS .............................................................................. 58 
8.1. 
Analysis Objectives and Endpoints .................................................................... 58 
8.1.1. 
Analysis Objectives ............................................................................ 58 
8.1.2. 
Primary Endpoint ................................................................................ 59 
8.1.3. 
Secondary Endpoint ........................................................................... 59 
 
 
8.2. 
Analysis Conventions ........................................................................................ 59 
8.2.1. 
Analysis Sets ...................................................................................... 59 
8.3. 
Data Handling Conventions ............................................................................... 59 
8.4. 
Demographic Data and Baseline Characteristics ............................................... 60 
8.5. 
Efficacy Analysis................................................................................................ 60 
8.6. 
Safety Analysis .................................................................................................. 60 
8.6.1. 
Extent of Exposure ............................................................................. 60 
8.6.2. 
Adverse Events .................................................................................. 61 
8.6.3. 
Laboratory Evaluations ....................................................................... 61 
8.6.4. 
Other Safety Evaluations .................................................................... 61 
8.7. 
Pharmacokinetic Analysis .................................................................................. 61 
 
 
8.9. 
Sample Size ...................................................................................................... 62 
8.10. 
Interim Analysis ................................................................................................. 62 
8.11. 
Data Monitoring Committee ............................................................................... 62 
8.12. 
Cardiovascular Safety Endpoint Adjudication Committee .................................. 62 
9. 
RESPONSIBILITIES ..................................................................................................... 63 
9.1. 
Investigator Responsibilities .............................................................................. 63 
9.1.1. 
Good Clinical Practice ........................................................................ 63 
9.1.2. 
Institutional Review Board/Independent Ethics Committee Review 
and Approval ...................................................................................... 63 
9.1.3. 
Informed Consent ............................................................................... 64 
9.1.4. 
Confidentiality ..................................................................................... 64 
9.1.5. 
Study Files and Retention of Records ................................................. 64 
9.1.6. 
Electronic Case Report Forms ............................................................ 65 
9.1.7. 
Investigational Medicinal Product Accountability and Return .............. 66 
9.1.8. 
Inspections ......................................................................................... 66 
9.1.9. 
Protocol Compliance .......................................................................... 66 
9.2. 
Sponsor Responsibilities ................................................................................... 67 
9.2.1. 
Protocol Modifications ........................................................................ 67 
9.2.2. 
Study Report and Publications............................................................ 67 
9.3. 
Joint Investigator/Sponsor Responsibilities ........................................................ 67 
9.3.1. 
Payment Reporting ............................................................................. 67 
9.3.2. 
Access to Information for Monitoring ................................................... 68 
9.3.3. 
Access to Information for Auditing or Inspections ............................... 68 
9.3.4. 
Study Discontinuation ......................................................................... 68 

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10. REFERENCES ............................................................................................................. 68 
11. APPENDICES ............................................................................................................... 70 
 
Appendix 1. Investigator Signature Page ............................................................................. 71 
Appendix 2. Study Procedures Table ................................................................................... 72 
Appendix 3. Management of Clinical and Laboratory Adverse Events ................................. 75 
Appendix 4. Crohn’s Disease Activity Index (CDAI) and Patient Reported Outcomes – 2 
items (PRO2) ................................................................................................... 76 
Appendix 5. CTCAE Grading Scale for Severity of Adverse Events ..................................... 77 
Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements ............................................................................ 78 
Appendix 7. Clinical Laboratory Assessment Table ............................................................. 81 
 
 
LIST OF IN-TEXT TABLES 
 
Table 3-1. 
Dosing Regimens in LTE ................................................................................. 30 
Table 5-1. 
Prohibited Concomitant Medications ................................................................ 41 
Table 7-1. 
Grading of Adverse Event Severity .................................................................. 52 

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CLINICAL STUDY PROTOCOL HISTORY 
Clinical Study Protocol/Amendment # 
Date 
Main Rationale 
General/Country-Specific 
CSP Version 1.0 
15-Jul-2016 
Initial Clinical Study Protocol. 
General 
Amendment 1 
07-Sep-2016 
Updated Study Procedures Table and 
footnotes to reflect changes made to 
weekly visits assessments/procedures in 
the protocol. 
Protocol GS-US-419-3896 title changed 
from Open-Label to Long-Term Extension 
study. 
General 
Amendment 2 
11-Nov-2016 
Updated Study Procedures Table to reflect 
changes made to the study visit 
assessments/procedures in the protocol. 
General 
Amendment 3 
15-Jun-2017 
Updates were made in response to the 
South Korean Ministry of Food and Drug 
Safety request for the use of 200 mg in 
males in Korea to be limited to male 
subjects who had failed 2 classes of 
biologic therapies (any tumor necrosis 
factor-alpha [TNFα] antagonist and 
vedolizumab).  
Updated sections with emerging relevant 
clinical and pipeline data, and ensured 
consistency with Investigator Brochure 
(IB) Ed 12.  
Updated Study Procedures Table to reflect 
changes made to the study visit 
assessments/procedures in the protocol. 
General 
Amendment 4 
09-Mar-2018 
Clarification on inclusion/exclusion 
criteria including those surrounding 
hepatitis and tuberculosis (TB), clarified 
Day 1 visit procedures and provided 
additional flexibility for enhanced safety 
monitoring (suggested infectious workups 
for disease worsening). 
Updated the department name from Drug 
Safety and Public Health (DSPH) to 
Pharmacovigilance & Epidemiology 
(PVE) 
Updated the Study Procedures Table and 
footnotes to reflect changes made to the 

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Clinical Study Protocol/Amendment # 
Date 
Main Rationale 
General/Country-Specific 
study visit assessments/procedures in the 
protocol 
General 
Amendment 5 
09-Nov-2018 
To allow study-wide unblinding of GS-
US-419-3896 after the parent studies (GS-
US-419-4015, GS-US-419-4016 and GS-
US-419-3895) were unblinded. 
Inclusion criterion # 2 was amended to 
include a comprehensive list of the 
Gilead-sponsored Crohn’s disease (CD) 
parent studies eligible for roll-over into 
this long-term extension (LTE) study. 
General 
Amendment 5.1 
17-Apr-2019 
Updated to allow for continuation of 
concomitant vedolizumab use in subjects 
who were previously enrolled in study 
GS-US-419-4016. 
Canada, Israel, France, UK, US, and 
voluntary harmonisation procedure (VHP) 
countries 
Amendment 6 
05-Sep-2019 
Updated duration of treatment to 
432 weeks, or until filgotinib becomes 
commercially available, whichever comes 
first, to ensure continued access to 
filgotinib in subjects who have completed 
the parent study (GS-US-419-3896). 
Amended study drug interruption or 
discontinuation criteria to reflect that 
subjects with newly positive 
QuantiFERON® TB test (or centrally 
reported equivalent assay) are now 
considered for study drug interruption 
instead of permanent discontinuation. 
General 
Amendment 7 
23-Mar-2020 
Updated study unblinding language to 
clarify the unblinding process and to allow 
subject unblinding once the corresponding 
parent study (GS-US-419-4015, 
GS-US-419-4016, or GS-US-419-3895) 
was unblinded. 
Updated study drug interruption criteria to 
allow the investigator to make the 
assessment of active or latent TB infection 
based on subject’s individual risk factors 
and further evaluations per standard of 

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Clinical Study Protocol/Amendment # 
Date 
Main Rationale 
General/Country-Specific 
care upon seroconversion or sequential 
indeterminate QuantiFERON® TB tests. 
Changes were implemented at the request 
of the United States Food and Drug 
Administration (US FDA) regarding new 
safety information of other Janus kinase 
(JAK) inhibitors on the potential risk of 
thromboembolic events. 
A statement was added to clarify the 
procedures to be followed if the Data 
Monitoring Committee (DMC) 
recommended stopping the study due to 
lack of efficacy. 
General 
Amendment 8 
02-Dec-2021 
Changed sponsorship from Gilead 
Sciences, Inc. to Galapagos NV. The 
Galapagos study number 
(GLPG0634-CL-310) was added. 
General 
Amendment 9 
23-Nov-2022 
The duration of treatment and end of study 
were adapted due to the limited number of 
subjects expected to continue after 31 
January 2025 and to allow subjects from 
other filgotinib treatment studies for CD to 
be enrolled into this study. 
Dose interruption criteria regarding renal 
impairment and lymphopenia were added 
to align with the IB Edition 17, 15 Jul 
2022. 
The length of time women of childbearing 
potential should use effective 
contraception after cessation of filgotinib 
treatment was changed to align with the 
post-treatment visit. 
The requirements for male condom use 
and reporting of pregnancies in female 
partners were removed to align with the IB 
Edition 17, 15 Jul 2022. 
Monthly pregnancy testing in clinic was 
changed to allow at home testing for 
subjects outside the US to reduce the 
burden on subjects. 
General 
 

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SUMMARY OF CHANGES 
 
Amendment 9 (23-Nov-2022) 
The overall reasons for this amendment are: 
a 
To adapt the duration of treatment and end of study due to the limited number of subjects expected to 
continue after 31 January 2025 and to allow subjects from other filgotinib treatment studies for Crohn’s 
disease (CD) to be enrolled into this study. 
b 
To add dose interruption criteria regarding renal impairment and lymphopenia to align with the 
Investigator’s Brochure Edition (IB) 17, 15 Jul 2022. 
c 
To change the length of time women of childbearing potential should use effective contraception after 
cessation of filgotinib treatment to align with the post-treatment visit. 
d 
To remove the requirements for male condom use and for reporting pregnancies in female partners during 
this study to align with the IB Edition 17, 15 Jul 2022. 
e 
To allow monthly pregnancy testing either in clinic (when it coincides with a scheduled visit) or at home 
with follow-up contact for subjects outside the US to reduce the burden on subjects. 
In addition, minor updates and administrative corrections were made. 
The changes made to the clinical study protocol (CSP) GS-US-419-3896 (GLPG0634-CL-310 [DIVERSITY 
LTE]) Version 8.0, 02 December 2021, are listed below, with a brief rationale of each change and the 
applicable sections. 
Change and Rationale: The duration of treatment and end of study were adapted due to the limited number 
of subjects expected to continue after 31 January 2025 and to allow subjects from other filgotinib treatment 
studies for CD to be enrolled into this study. 
Applicable Section: 
Protocol Synopsis 
Definition of Terms (new section) 
1.3 Rationale for This Study 
1.3.1 Rationale for Dose3.2 Study Design 
3.3 Study Treatments 
3.4 Duration of Treatment 
3.7 End of Study 
4.2 Inclusion Criteria 
5.1 Randomization, Blinding and Treatment Codes 
6.2.1 Day 1 Visit 
6.3.2 (new section title) Every 4 Weeks From Day 1 (± 7 days) 
6.3.3 (new section title) Week 12 and Then Every 12 Weeks Thereafter From Day 1 (± 7 days) 
6.3.4 Every 24 Weeks From Day 1 (± 7 days) 
6.3.5 Every 48 Weeks From Day 1 (± 7 days) 
6.3.6 (new section) End of Treatment Visit 
Appendix 2. Study Procedures Table 

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Change and Rationale: A study drug interruption criterion for subjects experiencing moderate renal 
impairment (estimated creatinine clearance ≥ 35 mL/min and < 60 mL/min per Cockcroft-Gault formula) was 
added to align with the IB Edition 17, 15 Jul 2022. 
Applicable Section:  
3.5.1 Study Drug Interruption Considerations 
Change and Rationale: A study drug interruption criterion for subjects with an absolute lymphocyte count 
(ALC) < 500 cells/mm3 was added to align with the Investigator’s Brochure Edition 17, 15 Jul 2022. 
Applicable Section:  
3.5.1 Study Drug Interruption Considerations 
Change and Rationale: The length of time women of childbearing potential should use effective 
contraception after cessation of filgotinib treatment was changed to 30 days to align with the post-treatment 
visit. 
Applicable Sections: 
Protocol Synopsis 
4.3 Exclusion Criteria 
Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and Contraceptive 
Requirements 
Change and Rationale: The requirements for male subjects to use condoms and for pregnancies in female 
partners to be reported during this study were removed in alignment with the IB Edition 17, 15 Jul 2022. The 
use of a condom 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 
4.2 Inclusion Criteria 
4.3 Exclusion Criteria 
7.7.2.1 Instructions for Reporting Pregnancies 
Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and Contraceptive 
Requirements 
Change and Rationale: The requirement for female subjects to come to the clinic for monthly pregnancy 
testing was changed for subjects outside the US to allow for testing either in the clinic (when it coincides with 
a scheduled visit) or at home with a follow-up contact in order to reduce the burden on subjects. 
Applicable Sections:  
6.3.2 (new section title) Every 4 Weeks From Day 1 (± 7 days) 
Appendix 2. Study Procedures Table 
Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and Contraceptive 
Requirements 
An overview of the changes introduced in previous amendments can be found in the separate 
protocol amendment summary of changes document for each amendment. 
 

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Target Population: 
Subjects with CD who have completed* or met protocol specified 
efficacy discontinuation criteria in a prior filgotinib treatment 
study for CD. 
*A subject is defined as completed if they have completed all 
study visits and procedures as defined in the protocol or have 
completed treatment up to the primary endpoint. 
Duration of 
Treatment: 
Subjects will receive filgotinib or placebo until filgotinib becomes 
commercially available in the country or until the end of study (31 
January 2025), whichever comes first.  All subject visits, 
including the post-treatment (PTx) visit, must be completed by 31 
January 2025 at the latest. The maximum treatment duration will 
be approximately 7.5 years. 
Diagnosis and Main 
Eligibility Criteria: 
Inclusion Criteria 
Subjects will be eligible if they meet all of the following inclusion 
criteria: 
1) Must have the ability to understand and sign a written 
informed consent form (ICF), which must be obtained prior to 
initiation of study procedures associated with this trial 
2) Criterion modified per amendment 9 
2.1)  Must have enrolled in a CD parent protocol, GS-US-419-
4015, GS-US-419-4016 or GS-US-419-3895 or any other 
Gilead/Galapagos-sponsored filgotinib treatment study for CD 
3) Females of childbearing potential must have a negative 
pregnancy test at Day 1 and must agree to continued monthly 
pregnancy testing during use of filgotinib treatment 
4) Criterion modified per amendment 9 
4.1)  Female subjects of childbearing potential who engage in 
heterosexual intercourse must agree to use protocol specified 
method(s) of contraception for the duration described in 
Appendix 6 
5) Willingness to refrain from live or attenuated vaccines during 
the study and for 12 weeks after last dose of study drug  
6) Must have completed all required procedures or met protocol 
specified efficacy discontinuation criteria in a prior filgotinib 
treatment study for CD 
Exclusion Criteria 
Subjects who meet any of the following exclusion criteria are not 
to be enrolled in the study. 

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1) Subjects who are discontinued from a parent study for reasons 
other than disease worsening or lack of response or remission; 
eg, subjects who discontinue for safety or tolerability issues 
are not eligible for this study  
2) Known hypersensitivity to the study drug 
 
3) 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 
4) Criterion modified per amendment 9 
4.1)  Females who may wish to become pregnant and/or plan 
to undergo egg donation or egg harvesting for the purpose of 
current or future fertilization during the course of the study 
and for at least 30 days after the last dose of study drug 
5) Criterion deleted per amendment 9 
6) Criterion modified per amendment 9 
6.1)  Females of reproductive potential who are unwilling to 
abide by protocol-specified contraceptive methods as defined 
in Appendix 6 
7) Use of prohibited concomitant medications as outlined in 
Section 5.4.2 
Study Procedures/ 
Frequency: 
Study visits with safety procedures will occur at Week 2, Week 4, 
Week 12, and then every 12 weeks thereafter. until the End of 
Treatment (EoT) visit. The EoT visit will be scheduled when 
filgotinib becomes commercially available in the country or prior 
to the end of study on 31 January 2025, whichever comes first. 
Day 1 assessments will include medical history, symptom 
directed physical examination (PE) including body weight and 
height, vital signs, safety laboratory assessments, urine pregnancy 
test (for females of childbearing potential), PRO2 and CDAI, 
adverse events (AEs) and concomitant medication assessments. 
PRO2, CDAI, symptom directed PE including body weight, vital 
signs, safety laboratory analyses, urine pregnancy test (for 
females of child-bearing potential), AEs and concomitant 
medications assessments will occur at each study visit.  
Women of child-bearing potential will require urine pregnancy 
tests every 4 weeks starting from Day 1 for the entire duration of 
the study.  
Subjects rolling over from GS-US-419-4016 will require 
complete perianal fistulae assessment every 12 weeks. 

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Urine samples will be collected at Day 1 and once every 24 
weeks. 
Peripheral Blood Mononuclear Cell (PBMC) (United States [US] 
and Canadian sites only), 
, 
, 
 
, and 
 
 will be collected at Day 1 and once 
every 24 weeks.  
 
Tuberculosis (TB) QuantiFERON® (or centrally reported 
equivalent assay) testing and 
 will be completed at Day 1 
and once every 48 weeks. A standard 12-lead electrocardiogram 
(ECG) will be performed every 48 weeks.  
Flexible sigmoidoscopy/colonoscopy collection with biopsies is 
optional per standard of care. The date of the procedure may be 
requested for accuracy of data analysis. 
Other inflammatory bowel disease (IBD) therapies 
(eg, prednisone > 30 mg) not permitted in the parent protocol are 
not allowed in this study. Refer to Section 5.4 for further details. 
Increases to or the addition of oral medications for the treatment 
of CD are allowed provided their dose does not exceed what was 
allowed in the parent protocol. 
Subjects who complete all study treatment visits or discontinue 
early will return 30 days after the last dose of study drug for PTx 
safety assessments. All subject visits, including the PTx visit, 
must be completed by 31 January 2025 at the latest. 
Test Product, Dose, and 
Mode of 
Administration: 
Filgotinib 200 mg oral tablet, once daily 
Filgotinib 100 mg oral tablet, once daily  
Dosing regimen is determined by regimen in parent study and 
reason for exiting parent study, as noted in Section 3.3. 
Reference Therapy, 
Dose, and Mode of 
Administration: 
Placebo-to-match (PTM) filgotinib 200 mg oral tablet, once daily 
PTM filgotinib 100 mg oral tablet, once daily 
Criteria for Evaluation: 
 
Safety: 
Assessments of AEs and concomitant medications will continue 
throughout the duration of the study. Safety evaluations include 
documentation of AEs, PE (symptom driven), vital signs, and 
clinical laboratory evaluations (hematology, chemistry, and 
urinalysis). An ECG will be performed every 48 weeks. 
Efficacy: 
Efficacy will be evaluated in terms of changes in PRO2 and 
CDAI scores. 

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GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS 
 
5-ASA 
5-aminosalicylate 
6-MP 
6-mercaptopurine 
ADL 
Activities of Daily Living 
AE 
adverse event 
ALC 
absolute lymphocyte count 
ALT 
alanine aminotransferase 
AP 
abdominal pain 
AST 
aspartate aminotransferase 
AUC 
area under the plasma/serum/peripheral blood mononuclear cell concentration, drug 
versus time curve 
 
 
BMI 
body mass index 
CC&G 
Cockcroft-Gault 
CD 
Crohn’s disease 
CDAI 
Crohn’s Disease Activity Index 
CES 
Carboxylesterases 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CIA 
collagen-induced arthritis 
CK 
creatine kinase 
Cmax 
the maximum observed serum/plasma/peripheral blood mononuclear (PBMC) 
concentration of drug 
CMV 
Cytomegalovirus 
CNS 
central nervous system 
CPK  
creatine phosphokinase 
CrCl 
creatinine clearance 
CRO 
contract (or clinical) research organization  
CRP 
c-reactive protein 
CSR 
clinical study report 
CTCAE 
Common Terminology Criteria for Adverse Events 
CVEAC 
Cardiovascular Safety Endpoint Adjudication Committee 
CYP 
Cytochrome 
DAI 
disease activity index 
DMC 
Data monitoring committee 
DNA 
deoxyribonucleic acid 
DSS 
dextran sodium sulfate 
EC 
ethics committee 
ECG 
Electrocardiogram 
eCRF 
electronic case report form(s) 
EDC 
Electronic Data Capture  

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LLT 
Lower-Level Term 
LTE 
long-term extension 
mAb 
monoclonal antibody 
MACE 
major adverse cardiovascular events 
MedDRA 
Medical Dictionary for Regulatory Activities 
 
 
 
  
MTX 
Methotrexate 
NOEL 
no-observed-effect-levels 
NSAID 
Nonsteroidal Anti-inflammatory Drugs 
O&P 
ova and parasites test 
OAT 
organic anion transporters 
PBMC 
peripheral blood mononuclear cell 
PD 
Pharmacodynamic 
PE 
physical examination 
PEG 
polyethylene glycol 
PI  
principal investigator 
PK 
Pharmacokinetic 
PRO2 
Patient reported outcomes consisting of 2 items: abdominal pain severity and liquid 
stool frequency 
PT 
Preferred Term 
PTM 
Placebo-to-match 
PTx 
Post-Treatment 
Q1 
1st quartile 
Q3 
3rd quartile 
RA 
Rheumatoid Arthritis 
RNA 
ribonucleic acid 
ROC 
receiver operating characteristic 
RT-PCR 
reverse transcription polymerase chain reaction 
SADR 
serious adverse drug reaction 
SAE 
serious adverse event 
SAP 
Statistical Analysis Plan 
SD 
standard deviation 
 
 
SI 
international system of units  
SOC 
system organ class 
SOP 
standard operating procedure 
STAT 
signal transducer and activator of transcription 
SUSAR 
Suspected Unexpected Serious Adverse Reaction 
TB 
Tuberculosis 
TEAE 
treatment-emergent adverse event 
TgrasH2 
Transgenic 

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TNFα 
tumor necrosis factor-alpha 
TYK 
Tyrosine kinase 
UC 
ulcerative colitis 
UGT 
uridine 5’ diphosphate glucuronosyltransferase  
ULN 
upper limit of the normal range 
US 
United States 
 
 
WBC 
white blood cell 
 
  
 
DEFINITION OF TERMS 
 
Completed in any other 
Gilead/Galapagos-sponsored 
filgotinib treatment parent 
study for CD 
A subject is defined as completed if they have completed all study visits and 
procedures as defined in the protocol or have completed treatment up to the 
primary endpoint. 
 
 

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1. 
INTRODUCTION 
1.1. 
Background 
Crohn’s disease (CD) is a relapsing and remitting form of inflammatory bowel disease (IBD) that 
causes gastrointestinal signs and symptoms of diarrhea, abdominal pain, weight loss, and the 
passage of blood or mucous per rectum. The inflammation of CD can involve the mucosal 
surface of the gastrointestinal tract and penetrate through the full thickness of the gastrointestinal 
wall, including the serosal surface. Crohn’s disease is characterized by phenotype and location of 
involved bowel. The phenotypes include inflammatory, stricturing, and penetrating subtypes. 
Stricture formation can result in intestinal obstruction requiring surgical management. Over time, 
patients with repeated surgeries are at risk for developing short bowel syndrome and/or intestinal 
failure. Penetrating disease is characterized by fistula formation, which can be bowel to bowel, 
bowel to skin, or bowel to adjacent organ. Depending on location, penetrating disease can also 
require surgical management. Penetrating disease can also manifest with intra-abdominal 
abscess, a condition which can be life threatening if not treated early with systemic antibiotics. In 
addition, CD may affect other organ systems leading to rashes, joint pain and stiffness, fever, and 
weight loss {Baumgart 2012}. 
The incidence and prevalence of CD has been increasing, with bimodal peaks affecting young 
adults (15 to 35 years of age) and older adults aged 50 to 70 with the age of onset often occurring 
in children < 12 years of age. Although geographic variation does occur, the overall incidence of 
CD in the northern hemisphere ranges from 7 to 20 per 100,000 person years, with a 
prevalence of up to 300 per 100,000 people. In the United States (US) and Europe, up to 
1.5 million individuals may be affected and the incidence is on the rise in parts of Asia and the 
Middle East {Molodecky 2012}. 
The cause of CD is poorly understood, however a complex interplay of genetic predisposition, 
aberrant immune activation, and early infection during childhood may be involved. The 
importance of environmental triggers is suggested by increasing rates due to industrialization and 
improved domestic hygiene and sanitation. This “hygiene hypothesis” has also been implicated 
in various other autoimmune disorders {Ventham 2013}. 
To assess disease severity, a number of clinical scoring systems are utilized based upon signs, 
symptoms, laboratory parameters, imaging modalities, and endoscopy. The Crohn’s Disease 
Activity Index (CDAI) is one such scoring tool with scores ranging from 0 to over 600 based 
upon a composite of symptoms (eg, abdominal pain), signs (the presence of abdominal mass 
and weight), laboratory values (eg, hematocrit), and physician assessment amongst others. In this 
scoring system, patients with a score > 220 are defined as moderate to severe these comprise the 
patients with the greatest unmet medical need. The CDAI can also be used to determine how 
well a therapy is working, with therapeutic remission defined as a CDAI of < 150 points 
{Dignass 2010}. 

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The CDAI has 2 patient reported outcomes of interest in CD drug development: liquid or very 
soft stool frequency and abdominal pain. In the Patient Reported Outcomes (PRO2) for the 
current study, these symptoms are recorded daily for 7 days and averaged to determine sub score 
cut off values of ≤1 for abdominal pain and ≤3 for stool frequency that define clinical remission. 
As yet, the stool frequency and abdominal pain sub scores of the CDAI have not been used on 
their own in prospective clinical trials. 
A significant change in CD management and therapeutic strategy has occurred over the last 
decade. Recent therapeutic goals extend beyond symptomatic control and include long-term 
mucosal and 
 {Cheifetz 2013}. The ultimate aim is to change the natural 
course of the disease by slowing down or halting its progression, thus avoiding surgery or 
hospitalization. This is achieved by utilizing earlier, aggressive, and goal-directed therapy. Risk 
assessment and prediction by means of complex clinical, biochemical, and endoscopic markers 
has become the key to patient management, therapy optimization, and prediction of the outcome 
and side effects of medical therapy.  
Currently available biologic therapies focus on neutralizing cytokine activity or altering T-cell 
differentiation and homing Three monoclonal antibodies which inhibit tumor necrosis 
factor-alpha (TNFα), are currently marketed for the treatment of CD: infliximab (Remicade®), 
adalimumab (Humira® [approved in US and European Union {EU}]) and certolizumab pegol 
(Cimzia® [approved in US]). Vedolizumab (Entivyo®, a monoclonal antibody against 
α4β71100 integrin is also approved for moderately to severely active CD. Recently, ustekinumab 
(Stelara®), a monoclonal antibody directed against the p40 subunit of IL-23 and therefore an 
antagonist for both IL-12 and IL-23 signaling, has been approved for the treatment of CD. 
Leukocytapheresis therapy may be used in Japan {Fukunaga 2012}.Other investigational 
treatment approaches still in development include the administration of cytokines to stimulate 
innate immunity, the use of prebiotics to alter the gut flora, and blocking the IL-6 signaling 
pathway {Ito 2004, Korzenik 2016}. New treatments being tested in clinical trials includes janus 
kinase (JAK) inhibitors (eg, upadacitinib), and new biologic agents such as 
IL-23 p19 antagonists (eg, risankizumab) and a monoclonal antibody directed against β7 integrin 
(eg, etrolizumab). 
While the introduction of biologic therapies has significantly improved response rates in patients 
with moderately to severely active CD, long-term or durable remission rates are still low at 
approximately 20%. Many patients receiving biologic therapies develop neutralizing antibodies 
with resulting loss of efficacy. These agents may be associated with specific safety issues 
including but not limited to anaphylaxis, increased risk of infection including progressive 
multifocal leukoencephalopathy, and liver injury. Safe and effective treatment options which 
may be conveniently administered in a chronic setting would provide a significant treatment 
advance for patients with moderately to severely active CD. 

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1.2. 
Filgotinib (GS-6034) 
1.2.1. 
General Information 
Janus kinases (JAKs) are intracellular cytoplasmic tyrosine kinases (TYKs) that transduce 
cytokine signaling from membrane receptors through signal transducer and activator of 
transcription (STAT) to the nucleus of cells. JAK inhibitors block the signaling of various 
cytokines, growth factors, and hormones, including the proinflammatory cytokine interleukin 
(IL)-6. Four different types of JAKs are known, JAK1, JAK2, JAK3, and TYK2 which interact 
with different sets of membrane receptors. Inhibition of JAKs is a promising therapeutic option 
for a range of inflammatory conditions including rheumatoid arthritis (RA) and CD. 
Filgotinib (GS-6034, formerly known as GLPG0634) is a potent and selective inhibitor of JAK1. 
Filgotinib is approved in the European Union (EU), Japan, and Great Britain for treatment of 
moderate to severe active RA in adult patients. It is also approved for the treatment of 
moderately to severely active ulcerative colitis (UC) in adults in the EU, Japan and Great Britain. 
The compound has shown good preliminary efficacy in CD patients in Phase 2 studies. 
In humans, filgotinib is metabolized to form one major active metabolite, GS-829845. Though 
the potency of this metabolite is lower than the parent molecule, the overall exposure and peak 
plasma concentration in humans is higher than seen in all tested animal species. As a 
consequence, dedicated pharmacology and toxicology studies have been performed with 
GS-829845. Results from pharmacodynamics (PD) testing in healthy volunteers suggest that the 
clinical activity of filgotinib could result from the combination of the parent molecule and the 
metabolite. 
For further information on filgotinib, refer to the current Investigator’s Brochure (IB). 
1.2.2. 
Preclinical Pharmacology and Toxicology 
Filgotinib and its metabolite, GS-829845 have been extensively characterized in nonclinical 
studies. This program includes cellular assays demonstrating potency and selectivity of the 
compound against JAK1; efficacy studies in rats and mice; repeat-dose toxicity studies 
(up to 26 weeks in the rat and 39 weeks in the dog), in vitro and in vivo safety pharmacology and 
genetic toxicology studies, and reproductive toxicology studies in rats and rabbits.  
Additional toxicology studies conducted include phototoxicity studies and dose-range finding 
studies in support of a definitive juvenile toxicity study. A definitive juvenile toxicology study in 
rats is ongoing.  

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1.2.2.1. 
Nonclinical Pharmacology 
In cellular assays, filgotinib inhibits JAK1 signaling with the concentration of an inhibitor that is 
required for 50% inhibition (IC50) values of ≥ 179 nM, and demonstrates 30-fold selectivity over 
JAK2 in a human whole blood assay. Filgotinib has been profiled against 451 kinases and it is 
highly selective for JAK1; only 2.5% of kinases were inhibited ≥ 50% at 50-fold higher 
concentration than IC50 for JAK1. Broad receptor profiling (~70 receptors, ion channels, 
transporters and enzymes) did not reveal any off-target liabilities of the compound. Filgotinib 
demonstrated high potency in the rat collagen-induced arthritis (CIA) model as well as in the 
mouse dextran sulfate sodium (DSS)-induced colitis model, the latter of which is detailed below. 
The major human metabolite of filgotinib GS-829845 exhibits a similar JAK1 selectivity profile 
but is approximately 10-fold less potent as compared to parent filgotinib in vitro. 
The efficacy of filgotinib was evaluated in a prophylactic setting of the chronic mouse Dextran 
DSS model in two separate studies. Both studies evaluated oral dose levels of 10 and 30 mg/kg 
once daily. In addition to assessments of clinical score (disease activity index [DAI] and colon 
lesion score), serum markers of inflammation, immunohistochemical analysis, and expression of 
various chemokines and cytokines known to be altered in CD and UC patients were also 
evaluated in the distal colon of these mice.  
In both studies, the DAI score, which takes into account body weight loss, rectal bleeding, and 
stool consistency, was reduced by filgotinib in a dose-dependent manner, demonstrating that 
filgotinib protected mice against colitis induced by DSS. Histology of the colon revealed a 
filgotinib-mediated dose-related reduction in colon lesion score, correlating with reductions in 
DAI score.  
Additional end points evaluated across the DSS colitis model studies confirmed the suppression 
of various inflammatory markers including serum levels of C-reactive protein (CRP) and 
myeloperoxidase (MPO) and expression of IL-6 and TNFα (by reverse transcription polymerase 
chain reaction [RT-PCR]) by filgotinib. Immunohistochemical analysis of the colon confirmed 
inhibition of the JAK-STAT pathway by filgotinib as evidenced by a reduction of DSS-induced 
STAT3 phosphorylation. 
1.2.2.2. 
Safety Pharmacology 
Filgotinib and GS-829845 had no relevant effects on cardiovascular parameters 
(human ether-a-go-go [hERG] and dog telemetry studies), apart from a slight non-adverse 
increase in heart rate and arterial pressure with GS-829845 at exposures 8-fold that of the peak 
serum concentration (Cmax) in subjects with CD treated with 200 mg once daily filgotinib. There 
were no relevant effects on electrocardiogram (ECG) and QT. Filgotinib and GS-829845 had no 
effects on the respiratory system and central nervous system (CNS). 
1.2.2.3. 
Key Nonclinical Distribution, Metabolism, and Excretion Data 
Filgotinib demonstrates good oral bioavailability in mice, rats, dogs, and mini-pigs but less in 
monkeys. Plasma protein binding is low (< 70%) in all species, including humans. 

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The pharmacokinetics (PK) of filgotinib is generally dose proportional without gender 
differences. No accumulation occurs with repeated dosing. The mean terminal half-life after oral 
administration is 4 hours and 5 hours in rats and dogs, respectively. 
In the rat, filgotinib showed a rapid and even distribution throughout the body. High 
concentrations were observed only in the gastrointestinal (GI) tract and urinary bladder. 
Filgotinib does not penetrate into CNS tissues. The distribution of filgotinib indicates some 
affinity for melanin-containing tissues. 
Excretion is nearly complete within 24 hours (rat) and 48 hours (dog) post-dosing. In the rat, 
fecal and urinary excretion accounted for 40% and 53% of the administered dose, respectively, 
with a bile secretion of about 15%. In the dog, fecal excretion was the primary route of excretion, 
accounting for 59% of the administered dose, with urinary excretion accounting for 25%. 
In vitro metabolism studies in all species revealed one major metabolite (GS-829845). The 
formation of GS-829845 is mediated by carboxylesterases (CES) and is not dependent on 
cytochrome P450 (CYP). 
In vitro experiments have shown that drug-drug interactions with filgotinib and GS-829845 are 
unlikely. There is no inhibition or induction of CYPs or uridine 5’- diphosphate -
glucuronosyltransferase (UGTs), and no relevant inhibition of key drug transporters, including 
organic anion transporters (OATs), by filgotinib or GS-829845. OCT2 was inhibited by both 
filgotinib (IC50: 8.7 μM) and GS-829845 (IC50: 67 μM). The clinical relevance of the IC50 values 
for inhibition of OCT2 will be further evaluated. MATE1 was also weakly inhibited by filgotinib 
(IC50: 94 μM) and GS-829845 (IC50: >100 μM). Filgotinib was found to be a substrate of P-
glycoprotein (P-gp). 
1.2.2.4. 
Nonclinical Toxicology 
In repeat oral dose toxicity studies in both rats and dogs, the primary target tissues identified for 
filgotinib were the lymphoid tissues which are expected based on the pharmacology of JAK 
inhibition. Additional filgotinib-related findings were observed in the male reproductive organs 
of both species, and in the incisor teeth of rats only. Effects on the lymphoid system were fully 
reversible. Testicular toxicity demonstrated partial reversibility; however, sperm counts 
remained low. When using the mean exposure (AUC) at the NOAELs for the most sensitive 
species (the dog), the exposure margins compared to a 200 mg once daily dose of filgotinib in 
CD subjects are 2.5, 1.9, and 3.6-fold for the 26-week and 39-week chronic toxicity studies and 
the 39-week targeted exposure toxicity study, respectively. 
GS-829845-related findings in the repeat-dose toxicity studies were generally similar to those of 
the parent filgotinib; however, no testicular toxicity was noted following administration of 
GS-829845. 
Filgotinib and GS-829845 were non-genotoxic when evaluated in the bacterial mutagenicity 
assay, the in vitro mouse lymphoma mutagenicity assay, and the rat bone marrow micronucleus 
assay. 

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In embryofetal development studies, filgotinib and GS-829845 caused embryolethality and 
teratogenicity in rats and rabbits. Teratogenicity was observed at exposures slightly higher or 
similar to the human exposure at 200 mg once daily of filgotinib in subjects with CD. 
Administration of filgotinib did not affect female fertility but impaired fertility was observed in 
male rats at exposures approximately 12-fold the human exposure at 200 mg of filgotinib in 
subjects with CD. GS-829845 did not have any effects on fertility parameters in either male or 
female rats. 
In an in vitro phototoxicity study in 3T3 cells, the metabolite GS-829845 was positive for 
phototoxic potential and results with filgotinib were equivocal. A follow-up in vivo rat 
phototoxicity assay revealed a lack of phototoxic potential for both compounds. 
1.2.3. 
Clinical Trials of Filgotinib 
An overview of exposure and clinical studies conducted with filgotinib is available in the IB. 
1.2.3.1. 
Phase 2 Study in Crohn’s Disease (GLPG0634-CL-211, FITZROY) 
A Phase 2, randomized, double-blind, placebo-controlled, multicenter study with filgotinib was 
performed in subjects with active CD with evidence of mucosal ulceration {Vermeire 2017}. In 
Part 1, a total of 174 subjects were randomized (3:1) to receive either filgotinib 200 mg once 
daily or placebo for 10 weeks. Based on their clinical response in Part 1, subjects in Part 2 either 
continued their current treatment or were reassigned to a different treatment for an additional 
10 weeks. 
The efficacy of filgotinib was assessed by evaluating clinical remission (defined as CDAI 
score < 150), clinical response (defined as a decrease in CDAI of at least 100 points from 
baseline), and endoscopic response (defined as a decrease of at least 50% from baseline in the 
SES-CD score). 
The primary end point of the study was met: at Week 10, 60 of 128 subjects (46.9%) who 
received filgotinib achieved clinical remission versus 10 of 44 subjects (22.7%) who received 
placebo, a difference of 24.1% (P-value = 0.0077). In addition, filgotinib treatment was 
associated with increases in the proportion of subjects with clinical and endoscopic response 
compared with placebo.  
Overall, the safety profile of filgotinib in CD subjects was consistent with prior studies.  
For additional details about the efficacy and safety of filgotinib in CD, reference is made to the 
IB. 
1.3. 
Rationale for This Study 
A need for safer, better tolerated, durable efficacious therapies for patients with CD exists. 
Despite significant uptake in the use of anti-TNF agents, tolerability of anti-TNFs due to allergic 
and autoimmune reactions, lack of durable response, and significant increased risk of infection 
remain problematic. Filgotinib is a once daily, oral therapy that may prove efficacious without 
the risk of allergic and autoimmune phenomena observed with anti-TNF agents.  

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This is a long-term extension study (GS-US-419-3896; Galapagos Study ID GLPG0634-CL-310 
[DIVERSITY LTE]) to provide treatment with filgotinib for subjects with moderately to severely 
active CD (who have completed or met protocol specified efficacy discontinuation criteria in a 
prior filgotinib treatment study for CD) until filgotinib becomes commercially available in the 
country or until the end of study (31 January 2025), whichever comes first.. 
The purpose of this study is to observe the safety of long-term therapy and to ensure continued 
access to study drug for subjects who responded in the parent protocol of filgotinib. In addition, 
the study provides an open-label alternative at the highest possible dose (excluding males who 
are not dual-biologic refractory in the US and Korea, refer to Section 3.3 for further information) 
for subjects who had disease worsening or lack of response in the parent study. 
1.3.1. 
Rationale for Dose 
In Phase 2 trials in RA, pooled data with an exposure – response analysis demonstrated a 
dose-dependent increase in efficacy up to 200 mg total daily dose. In the Phase 2 study of CD, 
subjects treated in the 200 mg arm showed favorable response and remission rates 
(47% remission over 23% placebo and 59% response over 41% placebo). Remission rates at 
Week 20 for subjects who failed placebo for the first 10 weeks and commenced 100 mg from 
Weeks 10 to 20 was slightly lower (32%) though response rate was comparable (59%), 
indicating some level of efficacy at the 100 mg dose. These results are consistent with the 
relationship observed between filgotinib exposures and inhibition of pSTAT1 activation 
(ex-vivo) following single and multiple filgotinib doses, where maximal inhibition of pSTAT1 
activation (~78%) was achieved at or above 200 mg total daily dose and intermediate inhibition 
(~47%) at 100 mg {Namour 2015}. pSTAT1 data, in conjunction with considerations around the 
margin for nonclinical testicular findings, suggests assessing doses above 200 mg is not 
indicated. The presence of response in CD subjects in the exploratory 10 to 20 week arm of 
Study GLPG0634-CL-211, and study of multiple doses (ie, 100 mg and 200 mg once daily) in 
the present study will enable establishment of an appropriate nominal dose and determine the 
dose with the most favorable risk/benefit profile for CD subjects. The present study will ensure 
continued access to blinded dosing for specific subjects (those who complete a respective parent 
protocol through the end of that study). After the corresponding parent study (GS-US-419-4015, 
GS-US-419-4016, or GS-US-419-3895 [Galapagos Study ID: GLPG0634-CL-309]) is 
unblinded, subjects enrolled in the present study may be unblinded. Subjects who enroll from a 
parent study and receive blinded treatment in the DIVERSITY LTE study will have their 
DIVERSITY LTE treatment assignment unblinded when the parent study is unblinded. Subjects 
will continue on the same dose of open-label filgotinib as they had been receiving in blinded 
treatment. Subjects on placebo treatment will discontinue study drug and study participation. In 
addition, the present study allows open-label access at the highest possible dose for subjects who 
were non-responders or experienced disease worsening on blinded dosing in a parent study. At 
no time will males in the US and Korea who are not dual biologic refractory receive 200 mg.  
Subjects enrolled from other filgotinib treatment studies for CD will receive open-label 200 mg 
filgotinib daily. Reference is made to Section 3.3 for details about dosing regimen and definition 
of being dual biologic refractory. 

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1.4. 
Risk/Benefit Assessment for the Study 
Crohn’s disease is a progressive and potentially life-threatening disease with few treatment 
options, many of which result in primary or secondary nonresponse. Inflammatory bowel disease 
may lead to increased risk of gastrointestinal malignancies, impairment in quality of life, and 
ultimate need for life-altering surgery. Current treatment options are limited in ability to establish 
mucosal healing and clinical remission and have significant safety and efficacy limitations; for 
example, biologics have significant immunogenic risks and steroids are associated with increased 
morbidity and mortality. Remission rates are generally low when compared to placebo rates 
across most therapies for IBD. There remains substantial unmet need in IBD, particularly in 
moderate to severe disease. The lifelong nature of IBD increases the probability that subjects 
have cycled through various therapies, leaving few approved options. 
Nonclinical studies in rats and dogs identified lymphoid tissues and testes as target organs for 
filgotinib in long-term repeat-dose toxicity studies. Although decreased lymphocyte numbers 
observed in nonclinical studies have not been seen in clinical studies, hematological 
assessment will be performed throughout the present study to ensure this potential risk is 
appropriately monitored. In both rats and dogs, microscopic findings in the testes included germ 
cell depletion and degeneration, with reduced sperm content and increased cell debris in the 
epididymis and reduction in fertility in male rats. The dog was determined to be the most 
sensitive species. When using the (AUC at the NOAELs for dogs in the 26-week and 39-week 
chronic toxicity studies, and the 39 week targeted exposure toxicity study, the exposure margins 
compared with the highest proposed clinical dose of 200 mg once daily are 2.5, 1.9 and 3.6-fold 
respectively, in subjects with CD. A male safety study is planned to examine the potential effect 
of filgotinib on sperm/ejaculate parameters. Pending those results, the use of 200 mg in males in 
the US and Korea with CD or UC will be limited to subjects who have failed at least 
two biologic therapies (any TNFα antagonist and vedolizumab). Refer to the IB for further 
information about nonclinical and clinical testicular findings.  
Filgotinib has shown an increase of embryofetal malformations in rats and rabbits at exposures 
similar to, or slightly higher than, exposures associated with a 200 mg once daily dose in CD 
subjects, the use of highly effective contraception in the subject population is expected to 
mitigate this risk. 
JAK inhibition is expected to increase the risk of infection based on mechanism of action. Across 
the global studies in filgotinib, in general, active treated arms have increased incidences of 
infection versus placebo. In the present protocol, treatment interruption and discontinuation 
considerations surrounding infections are incorporated and sites and investigators will be trained 
regarding such circumstances. All subjects will be screened for tuberculosis (TB) and subjects 
with clinically significant active infections will be excluded. Malignancy has been reported in 
subjects on filgotinib; in the present trial, subjects will be required to have up to date colorectal 
cancer screening and surveillance and subjects with recent malignancies will be excluded as 
outlined in the inclusion criteria in the parent study. For further details about infections and 
malignancies, please refer to the IB. 
The potential benefits of JAK inhibition include improvement in clinical symptoms and mucosal 
and 
. JAK inhibition may be efficacious in the treatment of IBD based on 

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1) Failed any TNFα antagonist and vedolizumab at the time of randomization in studies 
GS-US-419-3895, GS-US-419-4015, and GS-US-419-4016, or 
2) Failed any TNFα antagonist and are taking vedolizumab at the time of randomization into the 
GS-US-419-4016 study.  
Details on dosing regimen for LTE are noted below in Table 3-1. 
Table 3-1. Dosing Regimens in LTE 
Dose in parent study 
Reason for exiting parent 
study 
Dose in LTE 
Dose in LTE after  
LTE Unblinding  
All Females, Non-US males and US & Korea dual refractory males 
200 mg filgotinib, 
blinded 
Study completed to end 
200 mg filgotinib + PTM 
100 mg (blinded dosing) 
200 mg filgotinib, 
open- label 
100 mg filgotinib, 
blinded 
Study completed to end 
100 mg filgotinib + PTM 
200 mg (blinded dosing) 
100 mg filgotinib, 
open-label 
Placebo, blinded 
Study completed to end 
PTM 100 mg + PTM 
200 mg (blinded dosing) 
Discontinue study drug 
200 mg filgotinib, open-
label/ blinded 
Completed treatment up to 
primary endpoint 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
Placebo, open-label/ 
blinded 
Completed treatment up to 
primary endpoint 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
blinded 
Disease worsening and/or 
failure to meet 
response/remission criteria 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
100 mg filgotinib, 
blinded 
Disease worsening and/or 
failure to meet 
response/remission criteria 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
Placebo, blinded 
Disease worsening and/or 
failure to meet 
response/remission criteria 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
Study completed to end 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
Study completed to end 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
Disease worsening and/or 
failure to meet 
response/remission criteria 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
Disease worsening and/or 
failure to meet 
response/remission criteria 
200 mg filgotinib, 
open-label 
200 mg filgotinib, 
open-label 

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Dose in parent study 
Reason for exiting parent 
study 
Dose in LTE 
Dose in LTE after  
LTE Unblinding  
US & Korea Males who have not failed at least two biologic therapies (any TNFα and vedolizumab) 
100 mg filgotinib, 
blinded 
Study completed to end 
100 mg filgotinib 
(blinded dosing) 
100 mg filgotinib, 
open-label 
Placebo, blinded 
Study completed to end 
PTM 100 mg (blinded 
dosing) 
Discontinue study drug 
100 mg filgotinib, 
blinded 
Disease worsening and/or 
failure to meet 
response/remission criteria 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
Placebo, blinded 
Disease worsening and/or 
failure to meet 
response/remission criteria 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
Study completed to end 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open-label 
Disease worsening and/or 
failure to meet 
response/remission criteria 
100 mg filgotinib, 
open-label 
100 mg filgotinib, 
open- label 
Abbreviations: LTE=long-term extension; PTM=placebo-to-match 
3.4. 
Duration of Treatment 
Subjects will receive filgotinib or placebo until filgotinib becomes commercially available in the 
country or until the end of study (31 January 2025), whichever comes first. All subject visits, 
including the PTx visit, must be completed by 31 January 2025 at the latest. The maximum 
treatment duration will be approximately 7.5 years. 
3.5. 
Criteria for Study Drug Interruption or Discontinuation  
3.5.1. 
Study Drug Interruption Considerations 
The medical monitor should be consulted prior to study drug interruption when medically 
feasible. 
Study drug interruption should be considered in the following circumstances; prior to resumption 
of study drug, the investigator should discuss the case with the medical monitor: 
• Intercurrent illness that would, in the judgment of the investigator, affect assessments of 
clinical status to a significant degree. 
• Subject is scheduled for elective or emergency surgery (excluding minor skin procedures 
under local or no anesthesia); timing of study drug pausing should be determined in 
consultation with the medical monitor. 
• Any subject who develops a new infection during the study should undergo prompt and 
complete diagnostic testing appropriate for an immunocompromised individual, and the 
subject should be closely monitored.  

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• Subjects with newly positive (converted) or 2 indeterminate QuantiFERON® 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 (ie, 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 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 screened at least yearly for signs and symptoms consistent with reactivation of 
TB. Any subject with active TB should be discontinued from the study. 
• After a confirmed laboratory change representing moderate renal impairment (estimated 
creatinine clearance [CrCl] ≥ 35 mL/min and < 60 mL/min per Cockcroft-Gault [CC&G] 
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 200 mg once daily 
in relation to the observation. 
⎯ If continuation of filgotinib 200 mg once daily 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. 
• For subjects with confirmed absolute lymphocyte count (ALC) less than 500 cells/mm3, 
retest within 3 to 7 days, filgotinib should be interrupted until grade returns to ≤ Grade 2 
(more than 500 cells/mm3). If ALC does not return to ≤ Grade 2 within 4 weeks or returns to 
less than 500 cells/mm3 following re-challenge with filgotinib, then filgotinib should be 
permanently discontinued and the subject managed according to local practice. 

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NOTE: During the time of study drug interruption for any of the above, the subject may continue 
to have study visits and to take part in procedures and assessments, if deemed medically 
appropriate by the investigator. 
The medical monitor should consult the medical leader as needed. 
3.5.2. 
Study Drug Discontinuation Considerations 
The medical monitor should be consulted prior to study drug discontinuation when medically 
feasible.  
Study drug must be permanently discontinued in the following instances: 
• Any opportunistic infection 
• Any serious infection that requires antimicrobial therapy or hospitalization, or any infection 
that meets SAE reporting criteria 
• Febrile neutropenia (temperature > 38.3°C or a sustained temperature of > 38°C for more 
than one hour) with absolute neutrophil count of < 1,000/mm3 
• Symptomatic anemia (eg, 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 
• Complicated herpes zoster infection (with multi-dermatomal, disseminated, ophthalmic, or 
CNS involvement) 
• Evidence of active HCV during the study, as evidenced by HCV RNA positivity 
• Evidence of active HBV during the study, as evidenced by HBV DNA positivity 
• Any thromboembolic event that meets SAE reporting criteria 
• Unacceptable toxicity, or toxicity that, in the judgment of the investigator, compromises the 
subject’s ability to continue study-specific procedures or is considered to not be in the 
subject’s best interest 
• Subject request to discontinue for any reason 
• Subject noncompliance 
• Pregnancy during the study; refer to Section 7.7.2.1 and Appendix 6 
• Discontinuation of the study at the request of the Sponsor, a regulatory agency or an 
institutional review board or independent ethics committee (IRB/IEC) 
• Subject use of prohibited concurrent therapy may trigger study drug discontinuation; 
consultation should be made with the medical monitor. 

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• Laboratory criteria: After becoming aware of any of the below described abnormal laboratory 
changes occurring at any one time, an unscheduled visit (ie, sequential visit) should occur to 
retest within 3 to 7 days (except creatinine, which should be retested 7 to 14 days apart). 
⎯ 2 sequential neutrophil counts < 750 neutrophils/mm3 (international system units [SI]: 
< 0.75 × 109 cells/L) 
⎯ 2 sequential platelet counts < 75,000 platelets/mm3(SI: < 75.0 × 109 cells/L) 
⎯ 2 sequential aspartate aminotransferase (AST) or alanine aminotransferase (ALT) 
> 3 times the upper limit of normal range (ULN) and at least one of the following 
confirmed values:  
■ total bilirubin > 2× ULN 
■ international normalized ratio (INR) > 1.5 
■ or accompanied by symptoms consistent with hepatic injury.  
For any subject with an initial AST or ALT elevation > 3× ULN, at the time of the 
second confirmatory draw, an INR, prothrombin time (PT) and partial thromboplastin 
time (PTT) must also be drawn. 
⎯ 2 sequential AST or ALT elevations > 5× ULN 
⎯ 2 sequential values for estimated CrCl < 35 mL/min based on the Cockcroft-Gault 
(CC&G) formula 
Male 
[(140–age in years) × (weight in kg)]/[72 × (serum creatinine in mg/dL)] 
= CLcr (mL/min) 
Female [(140–age in years) × (weight in kg) × 0.85]/[72 × (serum creatinine in mg/dL)] 
= CLcr (mL/min) 
• Subjects who were receiving blinded placebo at the time of study unblinding 
• Subjects are free to withdraw from the study at any time without providing reason(s) for 
withdrawal and without prejudice to further treatment. The reason(s) for withdrawal will be 
documented in the electronic case report form (eCRF).  
• Subjects who permanently discontinue study drug for any reason should discuss their 
continued care plan with their physicians.  
• Subjects who permanently discontinue study drug for pregnancy should not continue in the 
study; if there are any questions regarding permanent discontinuation, these should be 
discussed with the Sponsor. 

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• Subjects withdrawing from the study should complete Early Termination (ET), followed by 
PTx assessments 30 days after the last dose of study drug. 
Reasonable efforts will be made to contact subjects who are lost to follow-up. All contacts and 
contact attempts must be documented in the subject’s file. 
The Sponsor has the right to terminate the study at any time in case of safety concerns or if 
special circumstances concerning the study medication or the company itself occur, making 
further treatment of subjects impossible. In this event, the investigator(s) and relevant authorities 
will be informed of the reason for study termination. 
The medical monitor should consult the medical leader as needed. 
3.6. 
Disease Worsening Criteria 
Subjects meeting the following criteria should be considered to be discontinued from the study. 
• Any subject with significant disease worsening or lack of response to therapy based on 
investigator judgment may discontinue study drug at any time during the LTE 
• Disease worsening based on change in CDAI score may also be used to guide discontinuation 
of the subject: eg, increase in CDAI ≥100 from Day 1 in present study and CDAI >220 at 
2 consecutive visits.  
⎯ The disease worsening visits may include unscheduled visits (eg, a study visit followed 
by an unscheduled visit, or 2 sequential unscheduled visits). 
• If a subject experiences significant worsening of underlying CD, which requires any of the 
prohibited medications (refer to Section 5.4.2), or surgical intervention at any point during 
the study, treatment discontinuation should be considered at investigator’s discretion, in 
consultation with medical monitor if feasible (refer to Section 3.5.2).  
• A stool sample will be obtained for culture for pathogenic bacteria, ova and parasite 
evaluation, and C. difficile toxin assay, when a subject becomes symptomatic, including 
worsening or return of disease activity. 
3.7. 
End of Study 
End of Study is defined as last subject last visit. This will be when filgotinib becomes 
commercially available in the country or 31 January 2025, whichever comes first. All subject 
visits, including the PTx visit, must be completed by 31 January 2025 at the latest. 
3.8. 
Post Study Care 
Post study care is at the discretion of the treating investigator or physician. 

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4. 
SUBJECT POPULATION 
4.1. 
Number of Subjects and Subject Selection 
Approximately 1000 subjects who meet eligibility criteria at Day 1 will receive filgotinib or 
placebo. 
4.2. 
Inclusion Criteria 
Subjects must meet all of the following inclusion criteria to be eligible for participation in this 
study. 
1) Must have the ability to understand and sign a written ICF, which must be obtained prior to 
initiation of study procedures associated with this trial 
2) Criterion modified per amendment 9 
2.1) Must have enrolled in a CD parent protocol, GS-US-419-4015, GS-US-419-4016, 
GS-US-419-3895 or any other Gilead/Galapagos-sponsored filgotinib treatment study 
in CD 
3) Females of childbearing potential must have a negative pregnancy test at Day 1 and must 
agree to continued monthly pregnancy testing during use of filgotinib treatment 
4) Criterion modified per amendment 9 
4.1) Female subjects of childbearing potential who engage in heterosexual intercourse must 
agree to use protocol specified method(s) of contraception for the duration described 
as described in Appendix 6 
5) Willingness to refrain from live or attenuated vaccines during the study and for 12 weeks 
after last dose of study drug 
6) Must have completed all required procedures or met protocol specified efficacy 
discontinuation criteria in a prior filgotinib treatment study for CD 
4.3. 
Exclusion Criteria 
Subjects who meet any of the following exclusion criteria are not to be enrolled in this study. 
1) Subjects who are discontinued from a parent study for reasons other than disease worsening, 
or lack of response or remission; eg, subjects who discontinue for safety or tolerability issues 
are not eligible for the present study 
2) Known hypersensitivity to the study drug 

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3) 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 
4) Criterion modified per amendment 9 
4.1) Females who may wish to become pregnant and/or plan to undergo egg donation or 
egg harvesting for the purpose of current or future fertilization during the course of the 
study and for at least 30 days after the last dose of study drug 
5) Criterion deleted per amendment 9 
6) Criterion modified per amendment 9 
6.1) Females of reproductive potential who are unwilling to abide by protocol-specified 
contraceptive methods as defined in Appendix 6 
7) Use of prohibited concomitant medications as outlined in Section 5.4.2 
5. 
INVESTIGATIONAL MEDICINAL PRODUCTS 
5.1. 
Randomization, Blinding and Treatment Codes 
In the event of a medical emergency where breaking the blind is required to provide medical care 
to the subject, the investigator may obtain treatment assignment directly from the interactive web 
response system (IWRS) for that subject. The Sponsor recommends but does not require that the 
investigator contact the medical monitor before breaking the blind. Treatment assignment should 
remain blinded unless that knowledge is necessary to determine subject emergency medical care. 
The rationale for unblinding must be clearly explained in source documentation and on the 
eCRF, along with the date on which the treatment assignment was obtained. The investigator is 
requested to contact the medical monitor promptly in case of any treatment unblinding. 
Blinding of study treatment is critical to the integrity of this clinical trial; therefore, if a subject’s 
treatment assignment is disclosed to the investigator, the subject will have study treatment 
discontinued (unless study-wide unblinding occurs or is specific to subjects previously enrolled 
in a given parent study [GS-US-419-4015, GS-US-419-4016, GS-US-419-3895, or any other 
Gilead/Galapagos-sponsored filgotinib treatment study for CD]). All subjects will be followed 
until study completion unless consent to do so is specifically withdrawn by the subject. 
The Sponsor may independently unblind cases for expedited reporting of suspected unexpected 
serious adverse reactions (SUSARs). 
5.1.1. 
Blinding 
During the blinded treatment phase, subjects and all personnel directly involved in the conduct of 
the study will be blinded to treatment assignment. Specified personnel may be unblinded based 
on their study role. Study drug will be dispensed by the study pharmacist, or designee, in a 
blinded fashion to the subjects. Individuals in Clinical Packaging & Labeling or Clinical Supply 

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Management who have an Unblinded Inventory Manager role in the IWRS for purposes of study 
drug inventory management will remain unblinded. Individuals responsible for safety signal 
detection, investigational new drug safety reporting, and/or expedited reporting of SUSARs may 
be unblinded to individual case data and/or group level summaries. External (ie, contract 
research organizations) Biostatisticians and Programmers will be unblinded to verify treatment 
assignment and to support data monitoring committee data review if needed. Regulatory Quality 
and Compliance personnel in Research and Development may also be unblinded for purposes of 
supporting Quality Assurance activities and/or Regulatory Agency inspections. 
5.2. 
Description and Handling of Filgotinib and Placebo to Match 
(PTM) 
5.2.1. 
Formulation  
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) filgotinib 200 mg and 100 mg tablets are identical to the respective 
active tablets, in appearance. PTM filgotinib 200 mg and 100 mg 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. 
5.2.2. 
Packaging and Labeling  
Filgotinib and PTM filgotinib tablets are packaged in white, high density polyethylene (HDPE) 
bottles. Each bottle contains 30 tablets, silica gel desiccant and polyester packing material. Each 
bottle is enclosed with a white, continuous thread, child-resistant polypropylene screw cap fitted 
with an induction-sealed, aluminum-faced liner. 
Study drugs to be distributed to centers in the US, EU and other participating countries shall be 
labeled to meet applicable requirements of the US Food and Drug Administration (FDA), EU 
Guideline to Good Manufacturing Practice − Annex 13 (Investigational Medicinal Products), 
and/or other local regulations, as applicable. 
5.2.3. 
Storage and Handling  
Filgotinib and PTM filgotinib tablets should be stored at controlled room temperature of 
25°C (77°F); excursions are permitted between 15°C and 30°C (59°F and 86°F). Storage 
conditions are specified on the label. Until dispensed to the subjects, all bottles of study drugs 
should be stored in a securely locked area, accessible only to authorized site personnel. 

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To ensure the stability and proper identification, study drugs should not be stored in a container 
other than the container in which they were supplied. Consideration should be given to handling, 
preparation, and disposal through measures that minimize drug contact with the body. 
Appropriate precautions should be followed to avoid direct eye contact or exposure when 
handling. 
5.3. 
Dosage and Administration 
The study medication will consist of 200 mg and 100 mg filgotinib tablets and PTM 200 mg and 
100 mg filgotinib tablets for oral administration, to be taken once a day. 
For missed dose(s) of study medication, subjects should be instructed to take the missed dose(s) 
of study medication as soon as possible during the same day. If the missed dose is not taken on 
the original day, then subjects should not take the missed dose and the missed dose should be 
returned to the study drug bottle. Subjects should be cautioned not to double the next dose 
(ie, taking the missed dose of study drug with that day’s dose). 
5.4. 
Prior and Concomitant Medications 
At each study visit, the study center will record any and all concomitant medications taken by the 
subject since the last visit or during the visit (as applicable). All concomitant medications 
(prescription, peri-procedural medications, over-the-counter medications, including vaccines, 
vitamins, herbal, dietary supplements, and minerals) must be recorded in the concomitant 
therapy section of the eCRF. 
Effective current therapies should not be discontinued for the sole purpose of participating in this 
study. Subjects may receive medications as supportive care or to treat AEs as deemed necessary 
by the Investigator or the subject’s physician. Should subjects have a need to initiate treatment 
with any excluded concomitant medication, the medical monitor should be consulted prior to 
initiation of the new medication. In instances where an excluded medication is initiated prior to 
discussion with the Sponsor, the Investigator should notify the Sponsor as soon as he/she is 
aware of the use of the excluded medication. 
5.4.1. 
Allowed Concomitant Medications 
Doses for allowed concomitant medications for CD must remain within the acceptable dose 
limits from the parent protocol. Steroids cannot exceed prednisone at a prescribed dose of 
30 mg/day equivalents. Discontinuation or dose modifications within the limits of allowed doses 
are permitted at the discretion of the investigator. 
The allowed medications for CD are as follows: 
• Oral 5-ASA compounds  
• Azathioprine, 6-MP, or MTX* 
• Oral corticosteroid therapy (prednisone at ≤ 30 mg/day or budesonide at a dose 
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• Antidiarrheals for chronic diarrhea 
• Antibiotics for the treatment of CD (eg, metronidazole, ciprofloxacin) consistent with 
subject’s standard low-dose regimen or cyclic therapy 
*Subjects enrolling into this study from the GS-US-419-4016 study and are taking concomitant 
vedolizumab may continue to take vedolizumab during their participation in this study. These 
subjects cannot take concomitant azathioprine, 6-MP, or MTX. 
5.4.2. 
Prohibited Concomitant Medications 
The prohibited medications are as follows: 
Table 5-1. Prohibited Concomitant Medications 
Drug Class 
Agents Disallowed 
Strong P-gp Inducersa 
Anticonvulsants 
Phenobarbital, phenytoin, carbamazepine 
Antimycobacterials 
Rifabutin, rifapentine, rifampin 
Herbal/Natural Supplements 
St. John’s wort, danshen (Salvia Miltiorrhiza) 
Prohibited IBD Medications 
Corticosteroids 
Dose equivalent to > 30 mg/day of prednisone 
TNFα antagonist 
Infliximab, adalimumab, golimumab, certolizumab, or biosimilar agent 
Integrin antagonist 
Vedolizumabb and natalizumab 
Interleukin antagonist 
Ustekinumab 
JAK inhibitor 
Any JAK inhibitors including but not limited to tofacitinib, baricitinib, 
and upadacitinib 
Other (non-biologic) 
Cyclosporine, thalidomide, tacrolimus, 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 Prohibited Medications 
Chronic Nonsteroidal 
Anti-inflammatory Drugs (NSAIDs)c  
Aspirin, ibuprofen, naproxen, diclofenac, indomethacin, 
COX-2 inhibitors 
Other biologicsd 
Antibody based or other systemic biologics, eg, denosumab, trastuzumab 
Abbreviations: COX-2=Cyclooxygenase-2; JAK=Janus Kinase; NSAID=Nonsteroidal Anti-inflammatory Drugs; TNFα=tumor 
necrosis factor-alpha 
a 
May decrease study drug exposure and are excluded to avoid potential reduction in study drug activity. Pharmacokinetic 
(PK) results indicate that filgotinib is a P-gp substrate, as a single dose of 200 mg itraconazole (a potent P-gp inhibitor) 
increased filgotinib Cmax by 64% and AUCinf by 45% and had no effect on the major, active metabolite GS-829845. 
b 
Subjects enrolling into this study from the GS-US-419-4016 study and are taking concomitant vedolizumab may continue to 
take vedolizumab during their participation in this study. 
c 
Occasional use of NSAIDs for transient symptoms and daily use of aspirin up to 162.5 mg for the purpose of cardiovascular 
prophylaxis are permitted. 
d 
Other biologics may be allowed with the approval of the medical monitor 

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5.5. 
Vaccine Guidelines 
• Prior to study participation, it is recommended that the subject’s vaccinations be brought up 
to date according to local vaccination standards. 
• Live or attenuated vaccines (including, but not limited to varicella and inhaled flu vaccine) 
are prohibited within 30 days of Day 1, throughout the study, and for 12 weeks after the 
last dose of study drug. 
• Subjects should be advised to avoid routine household contact with persons vaccinated with 
live/attenuated vaccine components. General guidelines suggest that a study subject’s 
exposure to household contacts should be avoided for the below stated time periods: 
⎯ Varicella or attenuated typhoid fever vaccination–avoid contact for 4 weeks following 
vaccination 
⎯ Oral polio vaccination–avoid contact for 6 weeks following vaccination 
⎯ Attenuated rotavirus vaccine–avoid contact for 10 days following vaccination 
⎯ Inhaled flu vaccine–avoid contact for 1 week following vaccination 
• Inactivated vaccines (such as inactivated flu vaccines) should be administered according to 
local vaccination standards whenever medically appropriate; however, there are no available 
data on the concurrent use of filgotinib and its impact on immune responses following 
vaccination. 
5.6. 
Accountability for Study Drug  
The investigator is responsible for ensuring adequate accountability of all used and unused study 
drug. This includes acknowledgement of receipt of each shipment of study drug (quantity and 
condition). All used and unused study drug dispensed to subjects must be returned to the site. 
Study drug accountability records will be provided to each study site to: 
• Record the date received and quantity of study drug 
• Record the date, subject number, subject initials, the study drug number dispensed 
• Record the date, quantity of used and unused study drug returned, along with the initials of 
the person recording the information 
5.6.1. 
Investigational Medicinal Product Return or Disposal 
Please refer to Section 9.1.7. 

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6. 
STUDY PROCEDURES 
The study procedures to be conducted for each subject enrolled in the study are presented in 
tabular form in Appendix 2 and described in the text that follows.  
The investigator must document any deviation from protocol procedures and notify the Sponsor 
or contract research organization (CRO). 
6.1. 
Subject Enrollment and Treatment Assignment 
Subjects who meet the eligibility criteria at Day 1 will be enrolled. Dosing regimen is determined 
by regimen in parent study and reason for exit (reference Section 3.3. for details).  
6.2. 
Pretreatment Assessments 
6.2.1. 
Day 1 Visit 
LTE Day 1 Rollover from GS-US-419-3895 
Subjects that meet protocol specified non-response criteria based on Week 10 assessments in the 
GS-US-419-3895 study may enter this study after completing the Week 11 visit procedures in 
the GS-US-419-3895 study. After LTE consent is obtained, complete all Day 1 LTE procedures 
that are not duplicates of Week 11 procedures in the GS-US-419-3895 study.  
Subjects that meet the protocol specified disease worsening criteria in the GS-US-419-3895 
study may enter the LTE study after completing the visit procedures on the GS-US-419-3895 
study. The Day 1 LTE visit must occur within a 10 day window from the confirmatory visit that 
determined their disease worsening status in the GS-US-419-3895 study. After LTE consent is 
obtained, complete all Day 1 LTE procedures. 
Subjects that potentially meet protocol specified disease worsening criteria based on Week 58 
assessments in the GS-US-419-3895 study must have their Day 1 LTE within a 10 day window 
from the Week 58 visit, while awaiting laboratory results in order to complete the CDAI 
calculation. The potential meeting of protocol specified disease worsening criteria occurs if the 
second consecutive visit coincides with the Week 58 visit. All Week 58 procedures must be 
completed from the GS-US-419-3895 study. After LTE consent is obtained, complete all Day 1 
LTE procedures that are not duplicates of Week 58 procedures in the GS-US-419-3895 study. 
Subjects that complete Week 58 and do not meet protocol specified disease worsening criteria in 
the GS-US-419-3895 study may enter this study after completing the Week 58 procedures in the 
GS-US-419-3895 study. After LTE consent is obtained, complete all Day 1 LTE procedures that 
are not duplicates of Week 58 procedures in the GS-US-419-3895 study. 
LTE Day 1 Rollover from GS-US-419-4015 or GS-US-419-4016 
Subjects that are non-responders based on Week 10 assessments in the prior study must return 
for the Day 1 LTE visit within 10 days of Week 10. All Day 1 LTE procedures must be 
completed. 

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Subjects that met protocol specified disease worsening criteria in the prior study should have 
their Day 1 LTE visit within a 10 day window from the confirmatory visit that determined their 
disease worsening status. All Day 1 LTE procedures must be completed. 
Subjects that have completed the prior study up to and including Week 24 and did not meet 
protocol specified disease worsening criteria in the prior study should have their Day 1 LTE visit 
on the same day as Week 24. All Week 24 procedures must be completed along with any 
non-duplicate Day 1 LTE procedures.  
Subjects that flare at the time of their Week 24 visit may require visit rescheduling in order to 
have confirmation of disease worsening status. Under these circumstances, the Day 1 LTE visit 
cannot be scheduled until their final status is known. At this time, the Day 1 LTE visit should be 
scheduled within a 10 day window from the confirmatory visit to determine disease worsening 
status. 
LTE Day 1 Rollover from any other filgotinib treatment study for CD 
Subjects that have completed* a Gilead/Galapagos-sponsored parent study may enter this study 
up to 30 days after completing the end of study procedures in the parent study. After LTE 
consent is obtained, complete all Day 1 LTE procedures. 
*A subject is defined as completed if they have completed all study visits and procedures as 
defined in the protocol or have completed treatment up to the primary endpoint. 
Please refer to the Phase 2 studies’ subject rollover manual for details on rollover procedures. 
Day 1 LTE Procedures 
Subjects will be screened to ensure eligibility, and if confirmed, subjects will be enrolled on the 
same day and study drug dispensed. The following will be performed and documented at this 
visit: 
• Obtain written informed consent 
• Review inclusion/exclusion criteria and other protocol restrictions (Sections 4.2 and 4.3) 
• Review medical history (ongoing AEs from prior filgotinib treatment studies should be 
recorded as medical history) 
• Review AEs and concomitant medications 
• TB Assessment QuantiFERON® (or centrally reported equivalent assay)  
• Review electronic diary (e-Diary) for completion from prior filgotinib treatment study when 
available and remind subjects of diary instructions 
• Collect the variables to calculate CDAI score (reference Appendix 4) 
⎯ Site enters patient assessments from Day 1 visit 
⎯ CDAI score calculated centrally after all components have been captured electronically 

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• Baseline PRO2 (reference Appendix 4) – centrally calculated using the patient reported 
symptoms of stool frequency and abdominal pain captured in the electronic diary 
• Symptom-directed physical examination (PE)  
• Transfer a copy of the subject’s last perianal fistulae assessment into source documentation 
(for subjects rolling over from GS-US-419-4016 only)  
• Obtain weight and height  
• Obtain vital signs (resting blood pressure, respiratory rate, pulse, and temperature) 
• Obtain blood samples (reference Study Procedures Table [Appendix 2]) 
⎯ HBV Surveillance Guidelines 
■ Subjects with positive HBcAb and HBV DNA < LLOQ in a parent CD protocol will 
require ongoing HBV DNA monitoring every 3 months during this study. These 
subjects may also require prophylactic treatment per investigator discretion in 
accordance with local guidelines/standard of care.   
■ In Japan and where required by local guidelines, subjects with positive HBcAb and/or 
positive HBsAb but with HBV DNA < LLOQ in a parent CD protocol will require 
ongoing HBV DNA monitoring every 4 weeks for at least 12 months after starting 
study drug in accordance with local guidelines during this study.   
■ Any subject who has HBV DNA ≥ LLOQ during the study will be discontinued 
(reference Section 3.5.2). 
• 
 
 
 
• Obtain stool samples (reference Study Procedures Table [Appendix 2])  
• Obtain urine sample (reference Study Procedures Table [Appendix 2]) 
⎯ Sample will be used for urinalysis and pregnancy test (for females of childbearing 
potential only) 
• Administer 
 surveys to subject 
• Enter subject information in the IWRS to receive assignment 
• Dispense study drug as directed by the IWRS 
• Instruct the subject on the packaging, storage, and administration of the study drug 
• Document first dose in LTE for the subject–If a subject has already taken study drug for that 
day within the parent protocol, first dose should take place on Day 2. 

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Please refer to Section 7 Adverse Events and Toxicity Management for details regarding the 
reporting of AEs and SAEs. 
6.3. 
Treatment Assessments 
6.3.1. 
Week 2 and Week 4 (± 3 days) 
On Week 2 and Week 4, the following evaluations are to be completed: 
• Review AEs and concomitant medications 
• Review e-Diary for completion and remind subjects of diary instructions 
• Collect the variables to calculate CDAI score (reference Appendix 4)  
⎯ Site enters patient assessments at each visit 
⎯ CDAI score calculated centrally after all components have been captured electronically 
• PRO2 (reference Appendix 4) – calculated centrally  
• Symptom-directed PE  
• Obtain weight  
• Obtain vital signs (resting blood pressure, respiratory rate, pulse, and temperature) 
• Obtain blood samples (reference Study Procedures Table [Appendix 2]) 
• Obtain urine sample (reference Study Procedures Table [Appendix 2]) 
⎯ Pregnancy test (for females of child-bearing potential only) –Week 4 only 
• Dispense study drug as directed by the IWRS–Week 4 only 
6.3.2. 
Every 4 Weeks From Day 1 (± 7 days) 
Once every 4 weeks from Day 1 until EoT or early discontinuation, women of childbearing 
potential must have a urine pregnancy test. The test will be performed at home or in the clinic if 
it coincides with a scheduled visit. In case of home urine pregnancy testing, the site will contact 
the subject to obtain the results and will record the information in the eCRF. For subjects in the 
US, all pregnancy tests will be carried out in the clinic. If any pregnancy test is positive, study 
drug should be immediately interrupted and the subject should have a serum pregnancy test in 
clinic. 

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6.3.3. 
Week 12 and Then Every 12 Weeks Thereafter From Day 1 (± 7 days) 
On Week 12 and then every 12 weeks thereafter from Day 1 until EoT or early discontinuation, 
the following evaluations are to be completed: 
• Review AEs and concomitant medications 
• Review e-Diary for completion and remind subjects of diary instructions 
• Collect the variables to calculate CDAI score (reference Appendix 4)  
⎯ Site enters patient assessments at each visit 
⎯ CDAI score calculated centrally after all components have been captured electronically 
• PRO2 (reference Appendix 4) – calculated centrally  
• Symptom-directed PE  
• Complete perianal fistulae assessment (for subjects rolling over from GS-US-419-4016 only)  
• Obtain weight  
• Obtain vital signs (resting blood pressure, respiratory rate, pulse, and temperature) 
• Obtain blood samples (reference Study Procedures Table [Appendix 2]) 
• Dispense study drug as directed by the IWRS 
6.3.4. 
Every 24 Weeks From Day 1 (± 7 days) 
Once every 24 weeks from Day 1 until EoT or early discontinuation, the following evaluations 
are to be completed: 
• Obtain fasting (8 hours with no food or drink except water) blood samples (reference Study 
Procedures Table [Appendix 2]) 
• Obtain stool samples (reference Study Procedures Table [Appendix 2]) 
 
  
• Obtain urine sample for urinalysis (reference Study Procedures Table [Appendix 2]) 

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6.3.5. 
Every 48 Weeks From Day 1 (± 7 days) 
Once every 48 weeks from Day 1 until EoT or early discontinuation, the following evaluations 
are to be completed: 
• TB Assessment (See Section 3.5.1 for further information) 
• Perform 12-lead ECG 
 
6.3.6. 
End of Treatment Visit 
The EoT visit will be scheduled when filgotinib becomes commercially available in the country 
or prior to the end of study on 31 January 2025, whichever comes first. 
The same assessments as for the Early Termination visit should be performed at the EoT visit 
(Section 6.6). 
6.4. 
Safety 
6.4.1. 
Thromboembolic Events 
Subjects experiencing a thromboembolic event should be evaluated for the overall risk of 
recurrent thromboembolism and referred to a specialist for further testing as appropriate 
(including but not limited to evaluation for an underlying inherited hypercoagulable state).  
6.5. 
Post-Treatment Assessments (± 3 days) 
All subjects must complete the Post-Treatment (PTx) assessments 30 days after the last dose of 
study drug. 
The following evaluations are to be completed: 
• Symptom-directed PE 
• Complete perianal fistulae assessment (for subjects rolling over from GS-US-419-4016 only)  
• Obtain weight  
• Review AEs and concomitant medications 
• Obtain vital signs (resting blood pressure, respiratory rate, pulse and temperature) 
• Obtain blood samples (reference Study Procedures Table [Appendix 2]) 
• Obtain urine sample (reference Study Procedures Table [Appendix 2]) 

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⎯ Sample will be used for pregnancy test (for females of childbearing potential only) 
6.6. 
Early Termination Assessments  
Early termination assessments should occur after the corresponding parent study is unblinded for 
all subjects who were receiving placebo. In addition, early termination assessments should occur 
for any subject who discontinues the study due to meeting study drug discontinuation criteria 
(see Section 3.5.2 Study Drug Discontinuation Considerations).  
The following evaluations are to be completed: 
• Review AEs and concomitant medications 
• Obtain vital signs (resting blood pressure, respiratory rate, pulse and temperature) 
• Symptom-directed PE  
• Complete perianal fistulae assessment (for subjects rolling over from GS-US-419-4016 only)  
• Obtain weight  
• Obtain blood samples (reference Study Procedures Table [Appendix 2]) 
• Obtain urine sample (reference Study Procedures Table [Appendix 2])  
⎯ Sample will be used for pregnancy test (for females of childbearing potential only) 
• Collect the variables to calculate CDAI score (reference Appendix 4)  
⎯ Site enters patient assessments at each visit 
⎯ CDAI score calculated centrally after all components have been captured electronically 
• PRO2 (reference Appendix 4) – calculated centrally 
6.7. 
Assessments After Study Unblinding  
After study unblinding, subjects who were receiving placebo will discontinue study drug and 
study participation. Subjects should attend the clinic at their next scheduled study visit or earlier 
during an unscheduled visit and undergo the early termination assessments as described in 
Section 6.6 followed by the PTx assessments 30 days after the last dose of study drug (see 
Section 6.5). 
After study unblinding, subjects who were receiving active filgotinib will continue to receive the 
same dose (as received blinded) of open-label filgotinib dosing. Subjects should attend the clinic 
at their next scheduled study visit and complete study procedures as per their next scheduled 
study visit.  

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6.8. 
End of Study 
Please refer to Section 3.7. 
6.9. 
Post Study Care 
Please refer to Section 3.8. 
6.10. 
Clinical Laboratory Assessments 
Please refer to Appendix 7. 
7. 
ADVERSE EVENTS AND TOXICITY MANAGEMENT 
7.1. 
Definitions of Adverse Events, Adverse Reactions, and 
Serious Adverse Events 
7.1.1. 
Adverse Events 
An adverse event (AE) is any untoward medical occurrence in a clinical study subject 
administered an investigational product, which does not necessarily have a causal relationship 
with the treatment. An AE can therefore be any unfavorable and/or unintended sign, symptom, or 
disease temporally associated with the use of an investigational product, whether or not 
considered related to the investigational product. Adverse Events may also include pre- or 
post-treatment complications that occur as a result of protocol specified procedures, lack of 
efficacy, overdose, drug abuse/misuse reports, or occupational exposure. Preexisting events that 
increase in severity or change in nature during or as a consequence of participation in the clinical 
study will also be considered AEs. 
An AE does not include the following: 
• Medical or surgical procedures such as surgery, endoscopy, tooth extraction, and transfusion. 
The condition that led to the procedure may be an adverse event and must be reported. 
• Pre-existing diseases, conditions, or laboratory abnormalities present or detected before the 
screening visit that do not worsen 
• Situations where an untoward medical occurrence has not occurred (eg, hospitalization for 
elective surgery, social and/or convenience admissions) 
• Overdose without clinical sequelae (See Section 7.7.1) 
• Any medical condition or clinically significant laboratory abnormality with an onset date 
before the consent form is signed and not related to a protocol-associated procedure is not an 
AE. It is considered to be pre-existing and should be documented on the medical history 
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7.1.2. 
Serious Adverse Events 
A serious adverse event (SAE) is defined as an event that, at any dose, results in the following: 
• Death 
• Life-threatening (Note: The term “life-threatening” in the definition of “serious” refers to an 
event in which the subject was at risk of death at the time of the event; it does not refer to an 
event that hypothetically might have caused death if it were more severe.) 
• In-patient hospitalization or prolongation of existing hospitalization 
• Persistent or significant disability/incapacity 
• A congenital anomaly/birth defect 
• A medically important event or reaction: such events may not be immediately 
life-threatening or result in death or hospitalization but may jeopardize the subject or may 
require intervention to prevent one of the other outcomes constituting SAEs. Medical and 
scientific judgment must be exercised to determine whether such an event is a reportable 
under expedited reporting rules. Examples of medically important events include intensive 
treatment in an emergency room or at home for allergic bronchospasm; blood dyscrasias or 
convulsions that do not result in hospitalization; and development of drug dependency or 
drug abuse. For the avoidance of doubt, infections resulting from contaminated 
investigational product will be considered a medically important event and subject to 
expedited reporting requirements. 
7.2. 
Assessment of Adverse Events and Serious Adverse Events 
The investigator or qualified sub-investigator is responsible for assessing AEs and SAEs for 
causality and severity, and for final review and confirmation of accuracy of event information 
and assessments. 
7.2.1. 
Assessment of Causality for Study Drugs and Procedures 
The investigator or qualified sub-investigator is responsible for assessing the relationship to IMP 
therapy using clinical judgment and the following considerations: 
• No: Evidence exists that the adverse event has an etiology other than the IMP. For SAEs, an 
alternative causality must be provided (eg, pre-existing condition, underlying disease, 
intercurrent illness, or concomitant medication). 
• Yes: There is reasonable possibility that the event may have been caused by the 
investigational medicinal product. 
It should be emphasized that ineffective treatment should not be considered as causally related in 
the context of adverse event reporting.  

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The relationship to study procedures (eg, invasive procedures such as venipuncture or biopsy) 
should be assessed using the following considerations: 
• No: Evidence exists that the adverse event has an etiology other than the study procedure. 
• Yes: The adverse event occurred as a result of protocol procedures (eg, venipuncture) 
7.2.2. 
Assessment of Severity 
The severity of AEs will be graded using the modified Common Terminology Criteria for 
Adverse Events (CTCAE), Version 4.03. For each episode, the highest grade attained should be 
reported. 
If a CTCAE criterion does not exist, the investigator should use the grade or adjectives: 
Grade 1 (mild), Grade 2 (moderate), Grade 3 (severe), Grade 4 (life-threatening) or 
Grade 5 (fatal) to describe the maximum intensity of the adverse event. For purposes of 
consistency with the CTCAE, these intensity grades are defined in Table 7-1 and Appendix 5. 
Table 7-1. Grading of Adverse Event Severity 
Grade 
Adjective 
Description 
Grade 1 
Mild 
Asymptomatic or mild symptoms; clinical or diagnostic observations only; 
intervention not indicated 
Grade 2 
Moderate 
Local or noninvasive intervention indicated; limiting age-appropriate instrumental 
ADL 
Grade 3 
Severe 
Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling; limiting self-
care ADL 
Grade 4 
Life-threatening 
Urgent intervention indicated 
Grade 5 
Death 
Death related AE 
* 
Activities of Daily Living (ADL) Instrumental ADL refer to opening preparing meals, shopping for groceries or clothes, 
using the telephone, managing money, etc.  
** Self-care ADL refer to bathing, dressing and undressing, feeding self, using the toilet, taking medications, and not bedridden  
7.3. 
Investigator Requirements and Instructions for Reporting Adverse 
Events and Serious Adverse Events to the Sponsor 
Requirements for collection prior to initiation of Day 1 LTE IMP: 
After informed consent, but prior to initiation of Day 1 LTE IMP, the following types of events 
should be reported on the eCRF: all SAEs and adverse events related to protocol mandated 
procedures. 

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7.3.1. 
Adverse Events 
Non-serious Adverse Events that occur prior to initiation of Day 1 LTE IMP: 
After LTE informed consent is signed, but prior to initiation of Day 1 LTE IMP, all non-serious 
AEs related to LTE protocol-mandated procedures must be reported on the LTE electronic case 
report form (eCRF). 
All other non-serious events that occur after LTE informed consent is signed, but prior to 
initiation of Day 1 LTE IMP, should be reported on the parent Study eCRFs. 
Non-serious Adverse Events that occur after initiation of Day 1 LTE IMP:  
Following initiation of Day 1 LTE IMP, all non-serious AEs, regardless of cause or relationship, 
until 30 days after last administration of LTE IMP, must be reported on the LTE eCRF. 
All AEs should be followed up until resolution or until the adverse event is stable, if possible. 
The Sponsor may request that certain AEs be followed beyond the protocol defined follow-up 
period. 
7.3.2. 
Serious Adverse Events 
Serious Adverse Events that occur prior to initiation of Day 1 LTE IMP: 
After LTE informed consent is signed, but prior to initiation of Day 1 LTE IMP, all SAEs related 
to LTE protocol-mandated procedures must be reported on the LTE eCRF. 
All other SAEs that occur after informed consent is signed for the parent study, but prior to 
initiation of Day 1 of the LTE IMP must be reported in the parent study eCRF.  
Serious Adverse Events that occur after initiation of Day 1 LTE IMP: 
All SAEs, regardless of causal relationship, must be reported to LTE study eCRF and the 
Sponsor from initiation of Day 1 of the LTE IMP and throughout the duration of the LTE study 
(including the protocol-required post treatment follow-up period).  
General SAE Guidance: 
Any SAEs and deaths that occur after the post-treatment follow-up visit but within 30 days of the 
last dose of study IMP, regardless of causality, should also be reported.  
Investigators are not obligated to actively seek SAEs after the protocol defined follow-up period. 
However, if the investigator learns of any SAEs that occur after study participation has 
concluded and the event is deemed relevant to the use of IMP, he/she should promptly document 
and report the event to the Sponsor. 
• All AEs and SAEs will be recorded in the eCRF database within the timelines outlined in the 
eCRF completion guideline.  

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• At the time of study start, SAEs may be reported using a paper serious adverse event 
reporting form. During the study conduct, sites may transition to an electronic SAE (eSAE) 
system. 
Electronic Serious Adverse Event Reporting Process 
• Site personnel record all SAE data in the eCRF database and from there transmit the SAE 
information to the Sponsor within 24 hours of the investigator’s knowledge of the event. 
Detailed instructions can be found in the eCRF completion guidelines. 
• If for any reason it is not possible to record the SAE information electronically, ie, the eCRF 
database is not functioning, record the SAE on the paper serious adverse event reporting 
form and submit within 24 hours as described below. 
Email:  
DIVERSITYLTE_safety@glpg.com 
• As soon as it is possible to do so, any SAE reported via paper must be transcribed into the 
eCRF Database according to instructions in the eCRF completion guidelines. 
• If an SAE has been reported via a paper form because the eCRF database has been locked, 
no further action is necessary. 
• For fatal or life-threatening events, copies of hospital case reports, autopsy reports, and other 
documents are also to be submitted by e-mail or fax when requested and applicable. 
Transmission of such documents should occur without personal subject identification, 
maintaining the traceability of a document to the subject identifiers. 
• Additional information may be requested to ensure the timely completion of accurate safety 
reports. 
• Any medications necessary for treatment of the SAE must be recorded onto the concomitant 
medication section of the subject’s eCRF and the event description section of the SAE form. 
7.4. 
Sponsor Reporting Requirements 
Depending on relevant local legislation or regulations, including the applicable US FDA Code of 
Federal Regulations (CFR), the EU Clinical Trials Directive (2001/20/EC) and relevant updates, 
and other country-specific legislation or regulations, the Sponsor may be required to expedite to 
worldwide regulatory agencies reports of SAEs, serious adverse drug reactions (SADRs), 
or SUSARs. In accordance with the EU Clinical Trials Directive (2001/20/EC), the Sponsor or a 
specified designee will notify worldwide regulatory agencies and the relevant IRB/IEC in 
concerned Member States of applicable SUSARs as outlined in current regulations.  
Assessment of expectedness for SAEs will be determined by the Sponsor or designee using 
reference safety information specified in the investigator's brochure (IB) or relevant local label as 
applicable.  

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All investigators will receive a safety letter notifying them of relevant SUSAR reports associated 
with any study IMP. The investigator should notify the IRB or IEC of SUSAR reports as soon as 
is practical, where this is required by local regulatory agencies, and in accordance with the local 
institutional policy. 
7.5. 
Clinical Laboratory Abnormalities and Other Abnormal 
Assessments as Adverse Events and Serious Adverse Events   
Laboratory abnormalities are usually not recorded as AEs or SAEs. However, laboratory 
abnormalities (eg, clinical chemistry, hematology, and urinalysis) independent of the underlying 
medical condition that require medical or surgical intervention or lead to investigational 
medicinal product interruption or discontinuation must be recorded as an AE, as well as an SAE, 
if applicable. In addition, laboratory or other abnormal assessments (eg, ECG, x-rays, vital signs) 
that are associated with signs and/or symptoms must be recorded as an AE or SAE if they meet 
the definition of an AE (or SAE) as described in Sections 7.1.1 and 7.1.2. If the laboratory 
abnormality is part of a syndrome, record the syndrome or diagnosis (ie, anemia) not the 
laboratory result (ie, decreased hemoglobin). 
Severity should be recorded and graded according to the CTCAE Grading Scale for Severity of 
Adverse Events and Laboratory Abnormalities (Appendix 5). 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. 
7.6. 
Toxicity Management 
All clinical and clinically significant laboratory toxicities will be managed according to uniform 
guidelines detailed in Appendix 3, and as outlined below. 
Refer to Section 3.5, Criteria for Study Drug Interruption or Discontinuation, for additional 
specific discontinuation criteria. Specific toxicity discontinuation criteria in Section 3.5 
supersede below general toxicity guidelines, and in general, where discrepancy is present, the 
more conservative criteria apply. The medical monitor should be consulted prior to study drug 
discontinuation when medically feasible. 
7.6.1. 
Grades 1 and 2 Laboratory Abnormality or Clinical Event 
Continue study drug at the discretion of the investigator. 
7.6.2. 
Grade 3 Laboratory Abnormality or Clinical Event 
• For a Grade 3 clinically significant laboratory abnormality or clinical event, IMP may be 
continued if the event is considered to be unrelated to IMP. 
• For a Grade 3 clinical event, or clinically significant laboratory abnormality confirmed by 
repeat testing, that is considered to be related to IMP, IMP should be withheld until the 
toxicity returns to ≤ Grade 2. 

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• If a laboratory abnormality recurs to ≥ Grade 3 following re-challenge with IMP and is 
considered related to IMP, then IMP should be permanently discontinued and the subject 
managed according to local practice. Recurrence of laboratory abnormalities considered 
unrelated to IMP may not require permanent discontinuation. 
7.6.3. 
Grade 4 Laboratory Abnormality or Clinical Event 
For a Grade 4 clinical event or clinically significant Grade 4 laboratory abnormality confirmed 
by repeat testing that is considered related to IMP, IMP should be permanently discontinued and 
the subject managed according to local practice. The subject should be followed as clinically 
indicated until the laboratory abnormality returns to baseline or is otherwise explained, 
whichever occurs first. A clinically significant Grade 4 laboratory abnormality that is not 
confirmed by repeat testing should be managed according to the algorithm for the new toxicity 
grade. 
Investigational medicinal product may be continued without dose interruption for a clinically 
non-significant Grade 4 laboratory abnormality (eg, Grade 4 creatine kinase [CK] after strenuous 
exercise or triglyceride elevation that is nonfasting or that can be medically managed) or a 
clinical event considered unrelated to IMP. 
Treatment-emergent toxicities will be noted by the investigator and brought to the attention of 
the medical monitor, who will have a discussion with the investigator and decide the appropriate 
course of action. Whether or not considered treatment-related, all subjects experiencing AEs 
must be monitored periodically until symptoms subside, any abnormal laboratory values have 
resolved or returned to baseline levels or they are considered irreversible, or until there is a 
satisfactory explanation for the changes observed. Any questions regarding toxicity management 
should be directed to the medical monitor. The medical monitor should consult the medical 
leader as needed. 
7.7. 
Special Situations Reports 
7.7.1. 
Definitions of Special Situations 
Special situation reports include all reports of medication error, abuse, misuse, overdose, 
occupational exposure, drug interactions, exposure via breastfeeding, unexpected benefit, 
transmission of infectious agents via the product, product complaints, counterfeit or falsified 
medicine, and pregnancy reports regardless of an associated AE. 
Medication error is any unintentional error in the prescribing, dispensing, preparation for 
administration or administration of an investigational product while the medication is in the 
control of a health care professional, patient, or consumer. Medication errors may be classified as 
a medication error without an AE, which includes situations of missed dose; medication error 
with an AE; intercepted medication error; or potential medication error. 
Abuse is defined as persistent or sporadic intentional excessive use of an investigational product 
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Misuse is defined as any intentional and inappropriate use of an investigational product that is 
not in accordance with the protocol instructions or the local prescribing information. 
An overdose is defined as an accidental or intentional administration of a quantity of an 
investigational product given per administration or cumulatively which is above the maximum 
recommended dose as per protocol or in the product labeling (as it applies to the daily dose of the 
subject in question). In cases of a discrepancy in drug accountability, overdose will be 
established only when it is clear that the subject has taken the excess dose(s). Overdose cannot 
be established when the subject cannot account for the discrepancy except in cases in which the 
investigator has reason to suspect that the subject has taken the additional dose(s). 
Occupational exposure is defined as exposure to an investigational product as a result of one's 
professional or non-professional occupation.  
Drug interaction is defined as any drug/drug, drug/food, or drug/device interaction. 
Unexpected benefit is defined as an unintended therapeutic effect where the results are judged to 
be desirable and beneficial.  
Transmission of infectious agents is defined as any suspected transmission of an infected agent 
through an investigational product. 
Product complaint is defined as complaints arising from potential deviations in the manufacture, 
packaging, or distribution of the investigational product. 
Counterfeit or falsified medicine: Any investigational product with a false representation of: 
a) its identity, b) its source, or c) its history. 
7.7.2. 
Instructions for Reporting Special Situations 
7.7.2.1. 
Instructions for Reporting Pregnancies 
The investigator should report pregnancies in female study subjects that are identified after 
initiation of study drug and throughout the study, including the post study drug follow-up period, 
to DIVERSITYLTE_safety@glpg.com using the pregnancy report form within 24 hours of 
becoming aware of the pregnancy.  
Refer to Section 7.3 and the eCRF completion guidelines for full instructions on the mechanism 
of pregnancy reporting. 
The pregnancy itself is not considered an AE nor is an induced elective abortion to terminate a 
pregnancy without medical reasons. 
Any premature termination of pregnancy (eg, a spontaneous abortion, an induced therapeutic 
abortion due to complications or other medical reasons) must be reported within 24 hours as an 
SAE. The underlying medical reason for this procedure should be recorded as the AE term. 

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A spontaneous abortion is always considered to be an SAE and will be reported as described in 
Section 7.3. Furthermore, any SAE occurring as an adverse pregnancy outcome post study must 
be reported to DIVERSITYLTE_safety@glpg.com. 
The subject should receive appropriate monitoring and care until the conclusion of the 
pregnancy. The outcome should be reported to DIVERSITYLTE_safety@glpg.com using the 
pregnancy outcome report form. If the end of the pregnancy occurs after the study has been 
completed, the outcome should be reported directly to DIVERSITYLTE_safety@glpg.com.  
Refer to Appendix 6 for Pregnancy Precautions, Definition for Female of Childbearing Potential, 
and Contraceptive Requirements. 
7.7.2.2. 
Reporting Other Special Situations 
All other special situation reports must be reported on the special situations report form and 
forwarded to DIVERSITYLTE_safety@glpg.com within 24 hours of the investigator becoming 
aware of the situation. These reports must consist of situations that involve study drug, but do not 
apply to concomitant medications.  
Special situations involving concomitant medications do not need to be reported on the special 
situations report form; however, special situations that result in AEs due to a concomitant 
medication, must be reported as an AE.  
Any inappropriate use of concomitant medications prohibited by this protocol should not be 
reported as “misuse,” but may be more appropriately documented as a protocol deviation. 
Refer to Section 7.3 and the eCRF completion guidelines for full instructions on special 
situations reporting. 
All clinical sequelae in relation to these special situation reports will be reported as AEs or SAEs 
at the same time using the AE eCRF and/or the SAE report form. Details of the symptoms and 
signs, clinical management, and outcome will be reported, when available. 
8. 
STATISTICAL CONSIDERATIONS 
8.1. 
Analysis Objectives and Endpoints 
8.1.1. 
Analysis Objectives 
The primary analysis objective is: 
• To observe the long-term safety of filgotinib in subjects who have completed or met protocol 
specified discontinuation criteria in a prior filgotinib treatment study for CD 
The secondary analysis objective is: 
• To evaluate the effect of filgotinib on PRO2 and CDAI scores 

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8.6.2. 
Adverse Events 
Adverse events will be coded using the Medical Dictionary for Regulatory Activities 
(MedDRA). System Organ Class (SOC), High-Level Group Term (HLGT), High-Level Term 
(HLT), Preferred Term (PT), and Lower-Level Term (LLT) will be attached to the clinical 
database. 
Treatment-Emergent Adverse Events (TEAEs) are defined as 1 or both of the following: 
• Any AEs with an onset date of on or after the study drug start date and no later than 30 days 
after permanent discontinuation of study drug 
• Any AEs leading to premature discontinuation of study drug 
Summaries (number and percentage of subjects) of TEAEs by SOC and PT will be provided. 
TEAEs will also be summarized by relationship to study drug and severity. In addition, TEAEs 
leading to premature discontinuation of study drug will be summarized and listed. 
8.6.3. 
Laboratory Evaluations 
Selected laboratory data (using conventional units) will be summarized using only observed data. 
Absolute value and change from baseline at all scheduled time points will be summarized. 
Graded laboratory abnormalities will be defined using the grading scheme defined in the 
CTCAE. 
Incidence of treatment-emergent laboratory abnormalities defined as values that increase at least 
one toxicity grade from baseline at any time post baseline will be summarized. If baseline data 
are missing, then any graded abnormality (ie, at least a Grade 1) will be considered treatment 
emergent. 
8.6.4. 
Other Safety Evaluations 
Individual data for PE findings, prior and concomitant medications and medical history will be 
provided. Vital signs measurements will be listed by subject and summarized by incidence of 
events/abnormalities or descriptive statistics as appropriate. 
8.7. 
Pharmacokinetic Analysis 
Not applicable. 
8.8. 
 
 
  

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• Myocardial Infarction 
• Stroke 
• Arterial thromboembolism 
• Venous thromboembolism (eg, deep venous thrombosis, pulmonary embolism) 
Further details will be specified in the CVEAC Charter.  
9. 
RESPONSIBILITIES 
9.1. 
Investigator Responsibilities 
9.1.1. 
Good Clinical Practice 
The investigator will ensure that this study is conducted in accordance with the principles of the 
Declaration of Helsinki, International Council for Harmonisation (ICH) guidelines, or with the 
laws and regulations of the country in which the research is conducted, whichever affords the 
greater protection to the study subject. These standards are consistent with the EU Clinical Trials 
Directive 2001/20/EC and GCP Directive 2005/28/EC. 
The investigator will ensure adherence to the basic principles of GCP, as outlined in 
21 CFR 312, subpart D, “Responsibilities of Sponsors and Investigators,” 21 CFR, part 50, and 
21 CFR, part 56. 
The investigator and all applicable sub-investigators will comply with 21 CFR, Part 54, 
providing documentation of their financial interest or arrangements with the Sponsor, or 
proprietary interests in the investigational drug under study. This documentation must be 
provided prior to the investigator’s (and any sub-investigator’s) participation in the study. The 
investigator and sub-investigator agree to notify the Sponsor of any change in reportable interests 
during the study and for 1 year following completion of the study. Study completion is defined 
as the date when the last subject completes the protocol-defined activities. 
9.1.2. 
Institutional Review Board/Independent Ethics Committee Review and 
Approval 
The investigator (or Sponsor as appropriate according to local regulations) will submit this 
protocol, ICF, and any accompanying material to be provided to the subject (such as 
advertisements, subject information sheets, or descriptions of the study used to obtain informed 
consent) to an IRB/IEC. The investigator will not begin any study subject activities until 
approval from the IRB/IEC has been documented and provided as a letter to the investigator. 
Before implementation, the investigator will submit to and receive documented approval from 
the IRB/IEC any modifications made to the protocol or any accompanying material to be 
provided to the subject after initial IRB/IEC approval, with the exception of those necessary to 
reduce immediate risk to study subjects. 

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9.1.3. 
Informed Consent 
The investigator is responsible for obtaining written informed consent from each individual 
participating in this study after adequate explanation of the aims, methods, objectives, and 
potential hazards of the study and before undertaking any study-related procedures. The 
investigator must use the most current IRB/IEC-approved consent form for documenting written 
informed consent. Each informed consent (or assent as applicable) will be appropriately signed 
and dated by the subject or the subject’s legally authorized representative and the person 
conducting the consent discussion, and also by an impartial witness if required by IRB/IEC or 
local requirements. 
9.1.4. 
Confidentiality 
The investigator must assure that subjects’ anonymity will be strictly maintained and that their 
identities are protected from unauthorized parties. Only subject initials, date of birth, another 
unique identifier (as allowed by local law) and an identification code will be recorded on any 
form or biological sample submitted to the Sponsor, IRB/IEC, or laboratory. Laboratory 
specimens must be labeled in such a way as to protect subject identity while allowing the results 
to be recorded to the proper subject. Refer to specific laboratory instructions or in accordance 
with local regulations. NOTE: The investigator must keep a screening log showing codes, and 
names for all subjects screened and for all subjects enrolled in the trial. Subject data will be 
processed in accordance with all applicable regulations.  
The investigator agrees that all information received from the Sponsor, including but not limited 
to the IB, this protocol, eCRF, the IMP, and any other study information, remain the sole and 
exclusive property of the Sponsor during the conduct of the study and thereafter. This 
information is not to be disclosed to any third party (except employees or agents directly 
involved in the conduct of the study or as required by law) without prior written consent from the 
Sponsor. The investigator further agrees to take all reasonable precautions to prevent the 
disclosure by any employee or agent of the study site to any third party or otherwise into the 
public domain. 
9.1.5. 
Study Files and Retention of Records 
The investigator must maintain adequate and accurate records to enable the conduct of the study 
to be fully documented and the study data to be subsequently verified. These documents should 
be classified into at least the following two categories: (1) investigator’s study file, and 
(2) subject clinical source documents. 
The investigator’s study file will contain the protocol/amendments, eCRF and query forms, 
IRB/IEC and governmental approval with correspondence, informed consent, drug records, staff 
curriculum vitae and authorization forms, and other appropriate documents and correspondence. 
The required source data should include sequential notes containing at least the following 
information for each subject: 
• Subject identification (name, date of birth, gender); 

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• Documentation that subject meets eligibility criteria, ie, history, PE, and confirmation of 
diagnosis (to support inclusion and exclusion criteria); 
• Documentation of the reason(s) a consented subject is not enrolled 
• Participation in study (including study number); 
• Study discussed and date of informed consent; 
• Dates of all visits; 
• Documentation that protocol specific procedures were performed; 
• Results of efficacy parameters, as required by the protocol; 
• Start and end date (including dose regimen) of IMP, including dates of dispensing and return; 
• Record of all AEs and other safety parameters (start and end date, and including causality 
and severity); 
• Concomitant medication (including start and end date, dose if relevant; dose changes); 
• Date of study completion and reason for early discontinuation, if it occurs. 
All clinical study documents must be retained by the investigator until at least 2 years or 
according to local laws, whichever is longer, after the last approval of a marketing application in 
an ICH region (ie, US, Europe, or Japan) and until there are no pending or planned marketing 
applications in an ICH region; or, if no application is filed or if the application is not approved 
for such indication, until 2 years after the investigation is discontinued and regulatory authorities 
have been notified. Investigators may be required to retain documents longer if specified by 
regulatory requirements, by local regulations, or by an agreement with the Sponsor. The 
investigator must notify the Sponsor before destroying any clinical study records. 
Should the investigator wish to assign the study records to another party or move them to another 
location, the Sponsor must be notified in advance. 
If the investigator cannot provide for this archiving requirement at the study site for any or all of 
the documents, special arrangements must be made between the investigator and the Sponsor to 
store these records securely away from the site so that they can be returned sealed to the 
investigator in case of an inspection. When source documents are required for the continued care 
of the subject, appropriate copies should be made for storage away from the site. 
9.1.6. 
Electronic Case Report Forms 
For each subject consented, an eCRF will be completed by an authorized study staff member 
whose training for this function is documented according to study procedures. The eCRF should 
be completed on the day of the subject visit to enable the Sponsor to perform central monitoring 
of safety data. The Eligibility Criteria eCRF should be completed only after all data related to 

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eligibility have been received. Subsequent to data entry, a study monitor will perform source data 
verification within the electronic data capture (EDC) system. Original entries as well as any 
changes to data fields will be stored in the audit trail of the system. Prior to database lock (or any 
interim time points as described in the clinical data management plan), the investigator will use 
his/her log in credentials to confirm that the forms have been reviewed, and that the entries 
accurately reflect the information in the source documents. The eCRF captures the data required 
per the protocol schedule of events and procedures. System-generated or manual queries will be 
issued to the investigative site staff as data discrepancies are identified by the monitor or the data 
management staff, who routinely review the data for completeness, correctness, and consistency. 
The site coordinator is responsible for responding to the queries in a timely manner, within the 
system, either by confirming the data as correct or updating the original entry, and providing the 
reason for the update (eg, data entry error). At the conclusion of the trial, the Sponsor will 
provide the site with a read-only archive copy of the data entered by that site. This archive must 
be stored in accordance with the records retention requirements outlined in Section 9.1.5. 
9.1.7. 
Investigational Medicinal Product Accountability and Return 
Where possible, IMP should be destroyed at the site. At the start of the study, the study monitor 
will evaluate each study center’s IMP disposal procedures and provide appropriate instruction for 
disposal or return of unused IMP supplies. If the site has an appropriate standard operating 
procedure (SOP) for drug destruction as determined by the Sponsor, the site may destroy used 
(empty or partially empty) and unused IMP supplies as long as performed in accordance with the 
site’s SOP. This can occur only after the study monitor has performed drug accountability during 
an on-site monitoring visit.  
A copy of the site’s IMP Disposal SOP or written procedure (signed and dated by the Principal 
Investigator [PI] or designee) will be obtained for the Sponsor site files. If the site does not have 
acceptable procedures in place, arrangements will be made between the site and the Sponsor 
(or the Sponsor’s representative) for return of unused study drug supplies.  
If IMP is destroyed on site, the investigator must maintain accurate records for all IMPs 
destroyed. Upon study completion, copies of the IMP accountability records must be filed at the 
site. Another copy will be returned to the Sponsor. 
The study monitor will review IMP supplies and associated records at periodic intervals. 
9.1.8. 
Inspections 
The investigator will make available all source documents and other records for this trial to the 
Sponsor’s appointed study monitors, to IRBs/IECs, or to regulatory authority or health authority 
inspectors. 
9.1.9. 
Protocol Compliance 
The investigator is responsible for ensuring the study is conducted in accordance with the 
procedures and evaluations described in this protocol. 

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9.2. 
Sponsor Responsibilities 
9.2.1. 
Protocol Modifications 
Protocol modifications, except those intended to reduce immediate risk to study subjects, may be 
made only by the Sponsor. The investigator must submit all protocol modifications to the 
IRB/IEC in accordance with local requirements and receive documented IRB/IEC approval 
before modifications can be implemented. 
9.2.2. 
Study Report and Publications 
A clinical study report (CSR) will be prepared and provided to the regulatory agency(ies). The 
Sponsor will ensure that the report meets the standards set out in the ICH Guideline for Structure 
and Content of CSRs (ICH E3). Note that an abbreviated report may be prepared in certain cases.  
Investigators in this study may communicate, orally present, or publish in scientific journals or 
other scholarly media only after the following conditions have been met: 
• The results of the study in their entirety have been publicly disclosed by or with the consent 
of the Sponsor in an abstract, manuscript, or presentation form or the study has been 
completed at all study sites for at least 2 years 
• The investigator will submit to the Sponsor any proposed publication or presentation along 
with the respective scientific journal or presentation forum at least 30 days before submission 
of the publication or presentation.  
• No such communication, presentation, or publication will include the Sponsor’s confidential 
information (See Section 9.1.4). 
• The investigator will comply with the Sponsor’s request to delete references to its 
confidential information (other than the study results) in any paper or presentation and agrees 
to withhold publication or presentation for an additional 60 days in order to obtain patent 
protection if deemed necessary. 
9.3. 
Joint Investigator/Sponsor Responsibilities 
9.3.1. 
Payment Reporting 
Investigators and their study staff may be asked to provide services performed under this 
protocol, eg, attendance at Investigator’s Meetings. If required under the applicable statutory and 
regulatory requirements, the Sponsor will capture and disclose to Federal and State agencies any 
expenses paid or reimbursed for such services, including any clinical trial payments, meal, travel 
expenses or reimbursements, consulting fees, and any other transfer of value. 

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9.3.2. 
Access to Information for Monitoring 
In accordance with regulations and guidelines, the study monitor must have direct access to the 
investigator’s source documentation in order to verify the accuracy of the data recorded in the 
eCRF. 
The monitor is responsible for routine review of the eCRF at regular intervals throughout the 
study to verify adherence to the protocol and the completeness, consistency, and accuracy of the 
data being entered on them. The monitor should have access to any subject records needed to 
verify the entries on the eCRF. The investigator agrees to cooperate with the monitor to ensure 
that any problems detected through any type of monitoring (central, on site) are resolved. 
9.3.3. 
Access to Information for Auditing or Inspections 
Representatives of regulatory authorities or of the Sponsor may conduct inspections or audits of 
the clinical study. If the investigator is notified of an inspection by a regulatory authority the 
investigator agrees to notify the medical monitor immediately. The investigator agrees to provide 
to representatives of a regulatory agency or the Sponsor access to records, facilities, and 
personnel for the effective conduct of any inspection or audit. 
9.3.4. 
Study Discontinuation 
Both the Sponsor and the investigator reserve the right to terminate the study at any time. Should 
this be necessary, both parties will arrange discontinuation procedures and notify the appropriate 
regulatory authority(ies), IRBs, and IECs. In terminating the study, the Sponsor and the 
investigator will assure that adequate consideration is given to the protection of the subjects’ 
interests. 
10. 
REFERENCES 
Baumgart DC, Sandborn WJ. Crohn's disease. Lancet 2012;380 (9853):1590-605. 
Cheifetz AS. Management of active Crohn disease. JAMA 2013;309 (20):2150-8. 
Dignass A, Van Assche G, Lindsay JO, Lemann M, Soderholm J, Colombel JF, et al. The second 
European evidence-based Consensus on the diagnosis and management of Crohn's 
disease: Current management. Journal of Crohn's & colitis 2010;4 (1):28-62. 
Fukunaga K, Matsumoto T. Current status and future perspectives of leukocytapheresis for 
inflammatory bowel disease. J Gastroenterol Hepatol 2012;27 (6):997-1003. 
Ito H, Takazoe M, Fukuda Y, Hibi T, Kusugami K, Andoh A, et al. A pilot randomized trial of a 
human anti-interleukin-6 receptor monoclonal antibody in active Crohn's disease. 
Gastroenterology 2004;126 (4):989-96; discussion 47. 
Khanna R, Zou G, D'Haens G, Feagan BG, Sandborn WJ, Vandervoort MK, et al. A 
retrospective analysis: the development of patient reported outcome measures for 

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the assessment of Crohn's disease activity. Aliment Pharmacol Ther 2015;41 
(1):77-86. 
Korzenik JR. Investigational therapies in the medical management of Crohn disease. Available 
at: www.uptodate.com/contents/4076. UpToDate 2016. 
Molodecky NA, Soon IS, Rabi DM, Ghali WA, Ferris M, Chernoff G, et al. Increasing incidence 
and prevalence of the inflammatory bowel diseases with time, based on 
systematic review. Gastroenterology 2012;142 (1):46-54 e42; quiz e30. 
Namour F, Diderichsen PM, Cox E, Vayssiere B, Van der Aa A, Tasset C, et al. 
Pharmacokinetics and Pharmacokinetic/Pharmacodynamic Modeling of Filgotinib 
(GLPG0634), a Selective JAK1 Inhibitor, in Support of Phase IIB Dose Selection. 
Clin Pharmacokinet 2015;54 (8):859-74. 
Sandborn WJ, Feagan BG, Hanauer SB, Lochs H, Lofberg R, Modigliani R, et al. A review of 
activity indices and efficacy endpoints for clinical trials of medical therapy in 
adults with Crohn's disease. Gastroenterology 2002;122 (2):512-30. 
Ventham NT, Kennedy NA, Nimmo ER, Satsangi J. Beyond gene discovery in inflammatory 
bowel disease: the emerging role of epigenetics. Gastroenterology 2013;145 
(2):293-308. 
Vermeire S, Schreiber S, Petryka R, Kuehbacher T, Hebuterne X, Roblin X, et al. Clinical 
remission in patients with moderate-to-severe Crohn's disease treated with 
filgotinib (the FITZROY study): results from a phase 2, double-blind, 
randomised, placebo-controlled trial. Lancet 2017;389:266-75. 
 
 

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11. 
APPENDICES 
Appendix 1. Investigator Signature Page 
Appendix 2. Study Procedures Table 
Appendix 3. Management of Clinical and Laboratory Adverse Events 
Appendix 4. Crohn’s Disease Activity Index (CDAI) and Patient Reported Outcomes – 2 
items (PRO2) 
Appendix 5. CTCAE Grading Scale for Severity of Adverse Events 
Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements 
Appendix 7. Clinical Laboratory Assessment Table 
 

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Appendix 1. Investigator Signature Page 
 
GALAPAGOS NV 
GENERAAL DE WITTELAAN L11 A3 
2800 MECHELEN 
BELGIUM 
 
STUDY ACKNOWLEDGEMENT 
 
A Long-Term Extension Study to Evaluate the Safety of Filgotinib in Subjects with 
Crohn’s Disease 
GS-US-419-3896 (GLPG0634-CL-310 [DIVERSITY LTE]),  
Amendment 9, 23 November 2022 
This protocol has been approved by Galapagos NV. The following investigator signature 
documents this approval. An electronic signature of the sponsor’s responsible person is provided 
at the end of the document. 
  
 
 
Signature 
 
 
 
Date 
 
 
INVESTIGATOR STATEMENT 
 
I have read the protocol, including all appendices, and I agree that it contains all necessary 
details for me and my staff to conduct this study as described. I will conduct this study as 
outlined herein and will make a reasonable effort to complete the study within the time 
designated. 
I will provide all study personnel under my supervision copies of the protocol and access to all 
information provided by Galapagos NV. I will discuss this material with them to ensure that they 
are fully informed about the drugs and the study. 
 
 
 
Principal Investigator Name (Printed) 
 
Signature 
 
 
 
 
Date 
 
Site Number 

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Appendix 2. Study Procedures Table 
Study Procedures 
Day 1a 
Week 2 
Week 4 
Every 
4 Weeks 
from 
Day 1 
Week 12 
and then 
every 
12 Weeks 
from Day 
1 Clinic 
Visit 
Every 
24 Weeks 
from 
Day 1 
Clinic 
Visit 
Every 
48 Weeks 
from 
Day 1 
Clinic 
Visit 
Early 
Termination 
(ET) / End 
of 
Treatment 
Visit 
Post-
Treatment 
(PTx)b 
 
± 3 days 
± 3 days 
± 7 days 
± 7 days 
± 7 days 
± 7 days 
 
± 3 days 
Written Informed Consent 
X 
 
 
 
 
 
 
 
 
Review Inclusion/Exclusion 
Criteria  
X 
 
 
 
 
 
 
 
 
Medical History 
X 
 
 
 
 
 
 
 
 
Symptom-Directed Examination 
(as needed) 
X 
X 
X 
 
X 
 
 
X 
X 
Perianal fistulae assessment 
(for subjects rolling over from 
GS-US-419-4016 only) c 
 
 
 
 
X 
 
 
X 
X 
Vital Signsd 
X 
X 
X 
 
X 
 
 
X 
X 
Height 
X 
 
 
 
 
 
 
 
 
Weight  
X 
X 
X 
 
X 
 
 
X 
X 
Hematology 
X 
X 
X 
 
X 
 
 
X 
X 
Chemistry 
X 
X 
X 
 
X 
 
 
X 
X 
Lipid Profile (fasting)e 
 
 
 
 
 
X 
 
 
 
Urinalysis 
X 
 
 
 
 
X 
 
 
 
Pregnancy Testf 
X 
 
X 
X 
 
 
 
X 
X 
HBV DNA monitoring (Japan)g 
X 
 
X 
X 
 
 
 
 
 
HBV DNA monitoring (other 
regions)h 
X 
 
 
 
X 
 
 
 
 

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a 
Day 1 visit for this study may occur at the same time as the final scheduled treatment visit of the prior filgotinib study or up to 30 days after completing the end of study 
procedures in the parent study, see Section 6.2.1. All procedures necessary for the final visit in the prior filgotinib study will be completed as well as any additional 
procedures required for this study. Procedures that are duplicates of the final visit from prior filgotinib study do not need to be performed again for this protocol. Day 1 may 
be delayed up to 10 days. If Day 1 of LTE is not the same as the last study visit of the prior study, a full set of Day 1 procedures should be performed. If a subject has already 
taken study drug for that day within the parent protocol, first dose should take place on Day 2.  
b 
The Post-Treatment (PTx) Visit should occur 30 days after the last dose of study drug. 
c 
The perianal fistula assessment entails tracking the clinical status of draining external openings of perianal fistulae that were identified at baseline of Study GS-US-419-4016. 
For additional details on the perianal assessment, refer to the Perianal Fistula Assessment Manual 
d 
Vital signs include resting blood pressure, respiratory rate, pulse, and temperature. 
e 
Fasting means no food or drink except water, for 8 hours 
f 
Females who are of childbearing potential only. A urine pregnancy test must be completed every 4 weeks at a minimum. The test will be performed at home or in the clinic if 
it coincides with a scheduled visit. In case of home urine pregnancy testing, the site will contact the subject to obtain the results and will record the information in the eCRF. 
For subjects in the US, all pregnancy tests will be carried out in the clinic. If any pregnancy test is positive, study drug should be immediately interrupted and the subject 
should have a serum pregnancy test in clinic.  
g 
In Japan, subjects with negative HBsAg, positive HBcAb and/or positive HBsAb in a parent CD protocol require HBV DNA monitoring every 4 weeks in accordance with 
local guidelines (Section 6.2.1).  
h 
In other regions, subjects with negative HBsAg and positive HBcAb require HBV DNA monitoring every 3 months in accordance with local guidelines (Section 6.2.1)  
i 
Subjects who were previously treated for TB do not need to have yearly QuantiFERON® (or centrally reported equivalent assay) tests but should be screened at least yearly 
for signs and symptoms of reactivation. 
j 
 
k 
 
l 
At Day 1 visit, review diary of subject reported components from parent study, if available. Subjects should begin filling out the Diary at the Day 1 visit and continue to fill it 
out throughout the study. 
m 
Colonoscopy with biopsies is optional per standard of care. The date of the procedure may be requested for accuracy of data analysis. 
n 
 
o 
Ongoing AEs from previous filgotinib studies should be recorded as medical history. Collection of AEs and SAEs related to protocol-mandated procedures will begin once 
informed consent is signed and will continue through the Post-Treatment (PTx) Visit. 

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

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Appendix 4. Crohn’s Disease Activity Index (CDAI) and Patient Reported Outcomes – 2 
items (PRO2) 
The Crohn’s Disease Activity Index (CDAI) will be calculated as follows: 
Variable no. 
Variable 
Variable description 
Multiplier 
1 
Liquid or very soft stool 
Daily stool count is summed for 7 days 
2 
2 
Abdominal pain 
Sum of 7 days of daily ratings as 
5 
0 = none, 1 = mild, 2 = moderate, 3 = severe 
3 
General wellbeing 
Sum of 7 days of daily ratings as 
7 
0 = generally well, 1 = slightly below par, 2 = poor, 
3 = very poor, 4 = terrible 
4 
Complications 
Number of listed complications: 
20 each 
Arthritis or arthralgia 
Erythema nodosum, pyoderma gangrenosum or 
aphthous stomatitis 
Iritis or uveitis 
Anal fissures or fistulae or abscess 
Other fistula 
Fever over 37.8°C [100°F] during past week 
5 
Use of anti-diarrheal 
medications 
Use of diphenoxylate or loperamide or other opiate 
for diarrhea 
30 
0 = No, 1 = Yes 
6 
Abdominal mass 
0 = none, 2 = questionable, 5 = definite 
10 
7 
Hematocrit* 
Males: 47 – Hct [%] 
Females: 42 – Hct [%] 
6 × 
difference 
* Result must be greater than or equal to 0. If 
negative result enter 0 
8 
Weight* 
Percentage deviation from standard weight 
1 
(1 – weight / standard weight) × 100 
* Limit of -10 
CDAI score 
 
 
TOTAL 
CDAI = Crohn’s Disease Activity Index; Hct = hematocrit 
{Sandborn 2002} 
The patient reported outcomes of liquid or very soft stool and abdominal pain (PRO2) score will 
be assessed as follows:  
Variable 
no. 
Variable 
Variable description 
1 
Liquid or very soft stool 
Mean of the daily stool count for 7 days 
2 
Abdominal pain 
Mean of 7 days of daily ratings as 
0 = none, 1 = mild, 2 = moderate, 3 = severe 
{Khanna 2015} 
Each PRO2 score will be rounded to the nearest integer for determination of eligibility and calculation of endpoints. 

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Appendix 5. CTCAE Grading Scale for Severity of Adverse Events 
Please refer to the Common Terminology Criteria for Adverse Events (CTCAE) Version 4.03, 
which can be found at: 
http://evs.nci.nih.gov/ftp1/CTCAE/CTCAE_4.03_2010-06-14_QuickReference_8.5x11.pdf  
For AEs associated with laboratory abnormalities, the event should be graded on the basis of the 
clinical severity in the context of the underlying conditions; this may or may not be in agreement 
with the grading of the laboratory abnormality. 
The only modification to the CTCAE criteria is the addition of a Grade 1 upper respiratory 
infection as follows: 
CTCAE 
V4.0 
Term 
Grade 1 
Grade 2 
Grade 3 
Grade 4 
Grade 5 
CTCAE V4.03 
AE Term 
Definition 
Upper 
respiratory 
infection 
Mild 
symptoms; 
symptomatic 
relief 
(eg, cough 
suppressant, 
decongestant) 
Moderate 
symptoms; 
oral 
intervention 
indicated 
(eg, antibiotic, 
antifungal, 
antiviral) 
IV antibiotic, 
antifungal, or 
antiviral 
intervention 
indicated; 
radiologic, 
endoscopic, 
or operative 
intervention 
indicated 
Life-threatening 
consequences; 
urgent 
intervention 
indicated 
Death 
A disorder 
characterized by 
an infectious 
process 
involving the 
upper respiratory 
tract 
(nose, paranasal 
sinuses, pharynx, 
larynx, or 
trachea). 
 

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Appendix 6. Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements 
The administration of filgotinib in embryofetal animal development studies resulted in decreased 
numbers of viable rat fetuses, increased resorptions, and visceral and skeletal malformations. 
Similar effects were noted in the rabbit. A safety margin relative to human exposure has not been 
identified. Pregnancy is contraindicated during use of filgotinib. 
For participation in this study, the use of highly effective contraception is required as outlined 
below for all subjects who are of childbearing potential. In addition, during the study women of 
childbearing potential must have at minimum a urine pregnancy test every 4 weeks. 
• 
Definitions 
⎯ Definition of Childbearing Potential 
For the purposes of this study, a female-born subject is considered of childbearing potential 
following the initiation of puberty (Tanner stage 2) until becoming post-menopausal, unless 
permanently sterile or with medically documented ovarian failure. Women who do not meet 
below criteria for being post-menopausal, are not permanently sterile, or do not have medically 
documented ovarian failure must have pregnancy testing as outlined by the protocol.  
Women are considered to be in a postmenopausal state when they are > 54 years of age with 
cessation of previously occurring menses for > 12 months without an alternative cause. 
Permanent sterilization includes hysterectomy, bilateral oophorectomy, or bilateral 
salpingectomy in a female subject of any age. Bilateral tubal ligation is not considered 
permanent sterilization. 
⎯ Definition of Male Fertility 
For the purposes of this study, a male-born subject is considered fertile after the initiation of 
puberty unless permanently sterilized by bilateral orchidectomy or has medical documentation of 
permanent male infertility. Vasectomy is not considered permanent sterilization. 
• 
Contraception for Female Subjects 
⎯ Study Drug Effects on Pregnancy and Hormonal Contraception 
Filgotinib is contraindicated in pregnancy as there is a possibility of human 
teratogenicity/fetotoxicity in early pregnancy based on non-clinical data. Data from a drug-drug 
interaction study of filgotinib and hormonal contraceptives (GS-US-417-3916) have 
demonstrated coadministration with filgotinib did not alter the pharmacokinetics of 
representative hormonal contraceptives levonorgestrel/ethinyl estradiol. 
For female subjects, hormonal contraceptives will be permitted as a form of contraception when 
used in conjunction with a barrier method (preferably a male condom). Details are outlined 
below. 
Please refer to the latest version of the filgotinib IB for additional information. 

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⎯ 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 pregnancy test at the Day 1 visit of the 
LTE. Pregnancy tests will be performed at monthly intervals thereafter. In the event of a delayed 
menstrual period (> one month between menstruations), a pregnancy test must be performed to 
rule out pregnancy. This is true even for women of childbearing potential with infrequent or 
irregular periods.  
Female subjects must agree to continue to use one of the following methods from Screening 
(parent study) until 30 days following the last dose of study drug.  
• 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 wish to use a hormonally based method, must use it in conjunction with a 
barrier method; the barrier method is to be used either by the female subject or by her male 
partner. Female subjects who utilize a hormonal contraceptive as one of their birth control 
methods must have consistently used the same method for at least three months prior to study 
dosing. Hormonally-based contraceptives and barrier methods permitted for use in this protocol 
are as follows: 
• Hormonal methods (each method must be used with a barrier method, preferably male 
condom) 
⎯ Oral contraceptives (either combined estrogen/progestin or progesterone only) 
⎯ Injectable progesterone 
⎯ Implants of levonorgestrel 
⎯ Transdermal contraceptive patch 
⎯ Contraceptive vaginal ring 

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• Barrier methods (each method must be used with a hormonal method) 
⎯ Male or female condom with or without spermicide 
⎯ Diaphragm with spermicide 
⎯ Cervical cap with spermicide 
⎯ Sponge with spermicide 
All female subjects must also refrain from egg donation and in vitro fertilization during treatment 
and until at least 30 days after the last study drug dose. 
• 
Unacceptable Birth Control Methods 
Birth control methods that are unacceptable include periodic abstinence (eg, calendar, ovulation, 
symptothermal, post-ovulation methods), withdrawal (coitus interruptus), spermicides only, and 
lactational amenorrhea method (LAM). Female condom and male condom should not be used 
together. 
• 
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 last study drug dose. Subjects who 
become pregnant or who suspect that they are pregnant during the study must report the 
information to the investigator and discontinue study drug immediately.  
Instructions for reporting pregnancy and pregnancy outcome are outlined in Section 7.7.2.1. 
• 
Pregnancy Testing 
All females of childbearing potential will have urine pregnancy testing every 4 weeks during 
their study participation. The test will be performed at home or in the clinic if it coincides with a 
scheduled visit. In case of home urine pregnancy testing, the site will contact the subject to 
obtain the results and will record the information in the eCRF. For subjects in the US, all 
pregnancy tests will be carried out in the clinic. If a urine pregnancy test is positive, the subject 
should stop study drug immediately, contact the investigator, and have confirmatory serum 
pregnancy test in clinic. 

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Appendix 7. Clinical Laboratory Assessment Table 
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 
(BUN) 
Calcium 
Chloride 
Serum creatinine 
Creatinine clearance 
CC&G 
Glucose 
Phosphorus 
Magnesium 
Potassium 
Sodium 
Creatine Phosphokinase 
(CPK) 
Appearance: 
Blood 
Color 
Glucose 
Leukocyte esterase 
pH 
Protein 
Urobilinogen 
 (
) 
 
 
 
 
Bacterial stool culture 
C-diff toxin 
Ova and parasites 
(O&P) 
 
 
 
Serum Immunoglobulin 
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: 
Urine pregnancy 
Serum pregnancy 
Fasting Lipids 
Triglycerides 
Cholesterol and its 
subfractions (high-density 
lipoprotein [HDL] and 
low density lipoprotein 
[LDL])