A Phase 2, Randomized, Double-Blind, Placebo Controlled Study Evaluating the Safety, Tolerability, and Efficacy of GS-9674 in Subjects With Primary Sclerosing Cholangitis Without Cirrhosis
Phase: PHASE2
Conditions: Primary Sclerosing Cholangitis
Sponsor: Gilead Sciences

Study Title: 
Sponsor: 
IND Number: 
EudraCT Number: 
Clinical Trials.gov 
Identifier: 
Indication: 
Protocol ID: 
Gilead Medical 
Monitor: 
Protocol Version/Date: 
(r'J GILEAU 
CLINICAL STUDY PROTOCOL 
A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study 
Evaluating the Safety, Tolerability, and Efficacy ofGS-9674 in 
Subjects with Primruy Sclerosing Cholangitis Without Cinhosis 
Gilead Sciences, Inc. 
333 Lakeside D1i.ve 
Foster City, CA 94404 
USA 
131031 
2016-00244 2-23 
NCT02943460 
Pti.mruy Sclerosing Cholangitis (PSC) 
GS-US-428-4025 
Name: 
Telephone: 
Fax: 
Email: 
Original: 
Amendment 1: 
Amendment 2: 
Georgia Li, MD 
PPD 
1-'1-'U 
PI-'U 
29 June 2016 
30 September 2016 
21 December 2016 
Amendment3: 
09 Febmruy 2017 
CONFIDENTIALITY STATEMENT 
The infonnation contained in this document, prui:iculru·ly unpublished data, is the property or 
under control of Gilead Sciences, Inc., and is provided to you in confidence as an investigator, 
potential investigator, or consultant, for review by you, yom staff, and an applicable Institutional 
Review Boru·d or Independent Ethics Committee. The inf01mation is only to be used by you in 
connection with authorized clinical studies of the investigational dmg described in the protocol. 
You will not disclose any of the infonnation to others without w1i.tten authorization from 
Gilead Sciences, Inc., except to the extent necessruy to obtain infonned consent from those 
persons to whom the dmg may be administered. 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 2
09 February 2017
TABLE OF CONTENTS
TABLE OF CONTENTS ..............................................................................................................................................2
LIST OF IN-TEXT TABLES........................................................................................................................................5
LIST OF IN-TEXT FIGURES ......................................................................................................................................5
PROTOCOL SYNOPSIS ..............................................................................................................................................6
GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS....................................................................14
1.
INTRODUCTION ..............................................................................................................................................18
1.1.
Background ............................................................................................................................................18
1.2.
GS-9674 .................................................................................................................................................19
1.2.1.
General Information .............................................................................................................19
1.2.2.
Nonclinical Toxicology........................................................................................................19
1.2.3.
Nonclinical Pharmacology ...................................................................................................20
1.2.4.
Nonclinical Pharmacokinetics..............................................................................................21
1.2.5.
Clinical Trials of GS-9674 ...................................................................................................22
1.3.
Rationale for this Study..........................................................................................................................25
1.4.
Risk/Benefit Assessment for the Study..................................................................................................26
1.5.
Compliance ............................................................................................................................................27
2.
OBJECTIVES.....................................................................................................................................................28
3.
STUDY DESIGN................................................................................................................................................29
3.1.
Study Design..........................................................................................................................................29
3.2.
Treatment Plan and Regimen .................................................................................................................30
3.3.
Biomarker Testing..................................................................................................................................30
3.3.1.
Biomarker Samples to Address the Study Objectives:.........................................................30
3.3.2.
Biomarker Samples for Optional Future Research...............................................................31
3.3.3.
Biomarker Samples for Optional Genomic Research...........................................................31
4.
SUBJECT POPULATION..................................................................................................................................32
4.1.
Number of Subjects and Subject Selection ............................................................................................32
4.2.
Inclusion Criteria....................................................................................................................................32
4.3.
Exclusion Criteria...................................................................................................................................33
5.
INVESTIGATIONAL MEDICINAL PRODUCTS ...........................................................................................36
5.1.
Randomization, Blinding and Treatment Codes ....................................................................................36
5.1.1.
Procedures for Breaking Treatment Codes...........................................................................36
5.2.
Description and Handling of GS-9674 and PTM GS-9674....................................................................36
5.2.1.
Formulation..........................................................................................................................36
5.2.2.
Packaging and Labeling .......................................................................................................37
5.2.3.
Storage and Handling...........................................................................................................37
5.3.
Dosage and Administration of GS-9674/PTM GS-9674........................................................................37
5.4.
Prior and Concomitant Medications.......................................................................................................38
5.5.
Prohibited Medications ..........................................................................................................................38
5.6.
Accountability for GS-9674/ PTM GS-9674 .........................................................................................39
5.6.1
Investigational Medicinal Product Return or Disposal........................................................40
6.
STUDY PROCEDURES ....................................................................................................................................41
6.1.
Subject Randomization and Treatment Assignment ..............................................................................41
6.2.
Pretreatment Assessments-Screening Visit ............................................................................................41
6.3.
Blinded Study Phase: Baseline/Day 1 Randomization and Assessments...............................................43

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 3
09 February 2017
6.4.
Treatment Assessments (Blinded Study Phase) .....................................................................................44
6.4.1.
Weeks 1, 2, 4 and 8 (± 3 days) .............................................................................................44
6.4.2.
Week 12 (± 3 days) ..............................................................................................................45
6.5.
Blinded Study Phase follow-up Visit (±5 days).....................................................................................47
6.6.
Open Label Extension (OLE) Phase (± 3 days for Weeks 1–12 and ± 5 days for Weeks 24-96) ..........48
6.7.
Unscheduled Visits.................................................................................................................................49
6.8.
OLE follow-up Visit (±5 days) ..............................................................................................................50
6.9.
Assessments for Premature Discontinuation from Study.......................................................................51
6.10.
Criteria for Discontinuation of Study Treatment....................................................................................51
6.11.
PK and PD Substudy Visits....................................................................................................................52
6.12.
Procedures and Specifications................................................................................................................52
6.12.1.
Clinical Laboratory Analytes ...............................................................................................52
6.12.2.
Medical History....................................................................................................................53
6.12.3.
Physical Examination...........................................................................................................53
6.12.4.
Quality of Life (QoL) Measures and Pruritus Assessments .................................................54
6.12.5.
Electrocardiogram................................................................................................................55
6.12.6.
FibroScan® ...........................................................................................................................55
6.12.7.
Magnetic Resonance Elastography.......................................................................................55
6.12.8.
Magnetic Resonance Cholangiopancreatography.................................................................55
6.13.
End of Study...........................................................................................................................................55
6.13.1.
Sample Storage.....................................................................................................................55
7.
ADVERSE EVENTS AND TOXICITY MANAGEMENT...............................................................................56
7.1.
Definitions of Adverse Events, Adverse Reactions, and Serious Adverse Events.................................56
7.1.1.
Adverse Events.....................................................................................................................56
7.1.2.
Serious Adverse Events........................................................................................................56
7.1.3.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events .........................................................................57
7.2.
Assessment of Adverse Events and Serious Adverse Events.................................................................57
7.2.1.
Assessment of Causality for Study Drugs and Procedures...................................................57
7.2.2.
Assessment of Severity ........................................................................................................58
7.3.
Investigator Requirements and Instructions for Reporting Adverse Events and Serious 
Adverse Events to Gilead.......................................................................................................................58
7.4.
Gilead Reporting Requirements.............................................................................................................60
7.5.
Toxicity Management ............................................................................................................................60
7.5.1.
PSC Specific Study Stopping Rule: .....................................................................................60
7.5.2.
Observation for Drug Induced Liver Injury (DILI):.............................................................60
7.6.
Special Situations Reports......................................................................................................................63
7.6.1.
Definitions of Special Situations..........................................................................................63
7.6.2.
Instructions for Reporting Special Situations.......................................................................64
8.
STATISTICAL CONSIDERATIONS................................................................................................................66
8.1.
Analysis Objectives and Endpoints........................................................................................................66
8.1.1.
Analysis Objectives..............................................................................................................66
8.1.2.
Primary Endpoint .................................................................................................................66
8.1.3.
Exploratory Endpoints..........................................................................................................67
8.2.
Analysis Conventions.............................................................................................................................67
8.2.1.
Analysis Sets ........................................................................................................................67
8.2.2.
Analysis by Study Phase ......................................................................................................69
8.3.
Data Handling Conventions ...................................................................................................................69
8.4.
Demographic Data and Baseline Characteristics ...................................................................................69
8.5.
Efficacy Analysis ...................................................................................................................................69
8.6.
Exploratory Analyses.............................................................................................................................69
8.7.
Safety Analysis.......................................................................................................................................70

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 4
09 February 2017
8.7.1.
Extent of Exposure...............................................................................................................70
8.7.2.
Adverse Events.....................................................................................................................70
8.7.3.
Laboratory Evaluations ........................................................................................................70
8.7.4.
Other Safety Evaluations......................................................................................................71
8.8.
Pharmacokinetic Analysis......................................................................................................................71
8.9.
Pharmacodynamics Analysis..................................................................................................................71
8.10.
Biomarker Analysis................................................................................................................................71
8.11.
Sample Size............................................................................................................................................71
8.12.
Data Monitoring Committee ..................................................................................................................71
9.
RESPONSIBILITIES..........................................................................................................................................73
9.1.
Investigator Responsibilities ..................................................................................................................73
9.1.1.
Good Clinical Practice..........................................................................................................73
9.1.2.
Institutional Review Board (IRB)/Independent Ethics Committee (IEC) 
Review and Approval...........................................................................................................73
9.1.3.
Informed Consent.................................................................................................................73
9.1.4.
Confidentiality......................................................................................................................74
9.1.5.
Study Files and Retention of Records ..................................................................................74
9.1.6.
Case Report Forms...............................................................................................................75
9.1.7.
Investigational Medicinal Product Accountability and Return.............................................76
9.1.8.
Inspections............................................................................................................................76
9.1.9.
Protocol Compliance............................................................................................................76
9.2.
Sponsor Responsibilities ........................................................................................................................77
9.2.1.
Protocol Modifications.........................................................................................................77
9.2.2.
Study Report and Publications .............................................................................................77
9.3.
Joint Investigator/Sponsor Responsibilities ...........................................................................................77
9.3.1.
Payment Reporting...............................................................................................................77
9.3.2.
Access to Information for Monitoring..................................................................................78
9.3.3.
Access to Information for Auditing or Inspections ..............................................................78
9.3.4.
Study Discontinuation..........................................................................................................78
10.
REFERENCES ...................................................................................................................................................79
11.
APPENDICES ....................................................................................................................................................80
Appendix 1.
Investigator Signature Page....................................................................................................81
Appendix 2.
Study Procedures Table for GS-US-428-4025 .......................................................................82
Appendix 3.
CTCAE Grading Scale for Severity of Adverse Events and Laboratory 
Abnormalities .........................................................................................................................86
Appendix 4.
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements...................................................................................................87

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 5
09 February 2017
LIST OF IN-TEXT TABLES
Table 1-1.
Exposure Margins for GS-9674 Based on Observed GS-9674 Exposure After 
Administration of 100 mg GS-9674 Under Fed Conditions in Cohort 5 Compared to 
Exposures Observed at NOAEL Doses in Mouse and Cynomolgus Monkey........................20
Table 1-2.
Preliminary Pharmacokinetic Results from Study GS-US-402-2102 Evaluating the 
Effect of DDIs on Administration of 100 mg GS-9674 with Food (Cohorts 1-3)..................24
Table 1-3.
Preliminary Pharmacokinetic Results from Study GS-US-402-2102 Evaluating the 
Effect of GS-9674 100 mg with Food on CYP3A, OATP/CYP3A, P-gp, OATP, or 
OATP/BCRP (Cohorts 5-6)....................................................................................................25
Table 5-1.
List of Medications Prohibited and to be used with Caution..................................................39
LIST OF IN-TEXT FIGURES
Figure 3-1.
Overall Study Design .............................................................................................................29

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 6
09 February 2017
PROTOCOL SYNOPSIS
Gilead Sciences, Inc.
333 Lakeside Drive
Foster City, CA 94404, USA
Study Title: 
A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study 
Evaluating the Safety, Tolerability, and Efficacy of GS-9674 in 
Subjects with Primary Sclerosing Cholangitis Without Cirrhosis
IND Number:
EudraCT Number:
Clinical Trials.gov 
Identifier:
131031
2016-002442-23
NCT02943460
Study Centers 
Planned:
Approximately 40 centers in North America and Europe
Objectives:
The primary objective of this study is to evaluate the safety and 
tolerability of GS-9674 in subjects with primary sclerosing 
cholangitis (PSC).
The exploratory objectives of this study are listed in Section 2. 
Study Design:
This is a Phase 2 randomized, double-blind, placebo-controlled study 
evaluating the safety, tolerability, and efficacy of GS-9674 in subjects 
with PSC without cirrhosis.
The study will consist of 2 phases, a Blinded Study Phase and an 
Open Label Extension (OLE) Phase. 
Blinded Study Phase: Includes a 4-week screening period, 12 weeks 
of blinded treatment, and a Blinded Study Phase follow-up visit, 4 
weeks after completion of blinded treatment. 
Subjects completing the Blinded Study Phase without permanently 
discontinuing study drug will be eligible to participate in the OLE 
Phase of the study.
OLE Phase:  Includes a 96-week OLE and an OLE Phase follow-up 
visit 4 weeks after completion of open label treatment.
Participation in the Blinded Study Phase can last up to 20 weeks and 
the OLE Phase can last up to 100 weeks, thus total study duration can 
be up 120 weeks.
Subjects meeting the study’s entry criteria will be randomly assigned 
in a 2:2:1 ratio to 1 of 3 treatment groups during the Blinded Study 
Phase as shown in the figure below:

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 7
09 February 2017
Randomization will be stratified by the presence or absence of 
ursodeoxycholic acid (UDCA) use. 
Number of Subjects 
Planned:
Approximately 50 subjects
Target Population:
Males and non-pregnant females between 18-70 years of age with 
PSC without cirrhosis
Duration of 
Treatment:
Total study duration of up to 120 weeks with up to 20 weeks for the 
Blinded Study Phase and up to 100 weeks for the OLE Phase.
Diagnosis and Main 
Eligibility Criteria:
Key inclusion and exclusion criteria are as follows:
Inclusion Criteria

Diagnosis of PSC based on cholangiogram (magnetic 
resonance cholangiopancreatography [MRCP], endoscopic 
retrograde cholangiopancreatography [ERCP], or 
percutaneous transhepatic cholangiogram [PTC]) within the 
previous 12 months;

Serum ALP > 1.67 x ULN;

For subjects on ursodeoxycholic acid (UDCA), the dose of 
UDCA must have been stable for at least 12 months prior to 
screening through the end of treatment. For subjects not on 
UDCA, no UDCA use for at least 12 months before screening 
through the end of treatment;

For subjects being administered biologic treatments (eg, anti-
tumor necrosis factor [TNF] or anti-integrin monoclonal 
antibodies), immunosuppressants or systemic corticosteroids,  
the dose must have been stable at least 3 months prior to
screening and anticipated to remain stable throughout the trial;

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 8
09 February 2017

Screening FibroSURE/FibroTest® <0.75, unless a historical liver 
biopsy within 12 months of screening does not reveal cirrhosis. In 
subjects with Gilbert’s syndrome or hemolysis, 
FibroSURE/FibroTest® will be calculated using direct bilirubin 
instead of total bilirubin.  
Exclusion Criteria

ALT > 10x ULN;

Total bilirubin > 2x ULN;

INR > 1.2 unless on anticoagulant therapy;

Serum albumin < 3.3 g/dL;

Cirrhosis of the liver as defined by any of the following:
a) Historical liver biopsy demonstrating stage 4 fibrosis 
(e.g. Ludwig stage 4 or Ishak stage ≥5); 
b) History of decompensated liver disease, including 
ascites, hepatic encephalopathy or variceal bleeding;
c) Liver stiffness > 14.4 kPa by FibroScan®

Small-duct PSC (histologic evidence of PSC with normal bile 
ducts on cholangiography);

Other causes of liver disease including secondary sclerosing 
cholangitis and viral, metabolic, alcoholic, and other 
autoimmune conditions. Subjects with hepatic steatosis may 
be included if there is no evidence of nonalcoholic 
steatohepatitis (NASH) in the opinion of the investigator or on 
liver biopsy;

Ascending cholangitis within 60 days of screening;

Presence of a percutaneous drain or bile duct stent;

Use of fibrates or obeticholic acid within 3 months prior to
screening and through the end of treatment;

Current, active inflammatory bowel disease (IBD) defined as 
a partial Mayo score of > 1 and/or a score on the Rectal 
Bleeding Domain > 0.
Please refer to section 4.2 and 4.3 of the protocol for detailed 
inclusion and exclusion criteria. 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Study Procedures/ 
Frequency: 
CONFIDENTIAL 
Blinded Study Phase 
Final 
Amendment 3 
After signing the informed consent form, subjects will complete a 
screening visit which will include the following assessments: 
complete medical history, complete physical examination (PE), vital 
signs (heart rate, systolic and diastolic blood pressure, respiratory 
rate, and body temperature), cirrhosis assessments, laboratory 
assessments (blood chemistry, hematology, coagulation panel, and 
biomarkers), calculation of partial Mayo score for subjects with IBD, 
serum pregnancy test (for females of childbearing potential), urine 
drug test and review of adverse events (AEs) related to screening 
procedures and concomitant medications (CMs). 
After the screening period, visits will occur at Baseline/Day 1 and at 
Weeks 1, 2, 4, 8, and 12. At minimum, vital signs, symptom-driven 
PE, safety laboratory tests (blood chemistry, hematology, and 
coagulation panel), calculation of partial Mayo score for subjects with 
IBD and review of adverse events and concomitant medications will 
be done at every visit. 
PPD 
Eligible subjects will be randomized to one of three treatment groups 
of the Blinded Study Phase. Prior to initial dosing, required 
Baseline/Day 1 assessments will be performed and will include 
symptom-driven PE, vital signs, laboratory assessments, pregnancy 
tests (for females of child-bearing potential), urine, blood, and stool 
collection for biomarker assessments, pruritus assessments and 
Quality of Life (QoL) questionnaires, standard 12-lead ECG, MRCP, 
MRE (if available), FibroScan ® (if available), review of AEs and 
CMs. 
PPD 
While on study, subjects will undergo the following procedures and 
laboratory assessments: 
• 
Symptom-directed PE and vital signs at Baseline/Day 1 and at 
Weeks 1, 2, 4, 8 and 12 
• 
Height at Baseline/Day 1 and weight at all visits 
• 
FibroScan® (if available) at Baseline/Day 1 and Week 12 
Page 9 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 10
09 February 2017

12-lead ECG at Baseline/Day 1 and Week 12 

C-peptide, insulin and hemoglobin A1c (HbA1c) at Baseline/Day 
1 and Week 12

PK and PD sampling at Baseline/Day 1 (PD only) and at Weeks 
1, 2, 4, 8 and 12 

Blood for Biomarker assessments at Baseline/Day 1 and at Weeks 
1, 4, and 12 

Urine Biomarker collection at Baseline/Day 1 and at Weeks 1, 4,
and 12

Urine pregnancy testing (females of childbearing potential only) 
at Baseline/Day 1 and Weeks 1, 4, 8 and 12 

Stool collection at Baseline/Day 1 and Week 12

Hematology, blood chemistry, coagulation panel (PT, PTT, INR) 
and fasting lipid profile at Baseline/Day 1 and Weeks 1, 2, 4, 8, 
and 12 

QoL Questionnaires: PBC-40, SF-36, and PSC Patient-Reported 
Outcome (PRO) at Baseline/Day 1 and Week 12 

Pruritus Assessments: Pruritus visual analog Scale (VAS) and 
5D-Itch at Baseline/Day 1 and at Weeks 1, 2, 4, 8, and 12

Partial Mayo score calculation at Baseline/Day 1 and at Weeks 1, 
2, 4, 8, and 12 for subjects with IBD
At the Blinded Study Phase follow up visit, subjects will have a 
symptom-driven PE, vital signs, laboratory assessments, urine 
pregnancy tests (for females of childbearing potential), urine, stool 
and blood collection for biomarker assessments, QoL and pruritus 
questionnaires (PBC-40, SF-36, PSC-PRO, Pruritus VAS and 
5D-Itch), weight, review of AEs, and review of CMs and serum will 
be drawn for hematology, blood chemistry, and a coagulation panel.
Subjects will be unblinded to their Blinded Study Phase treatment 
assignment after the primary analysis has been completed, 
approximately 6 weeks after all subjects have completed the Blinded 
Study Phase.
During the Blinded Study Phase early termination (ET) visit, subjects 
who prematurely discontinue participation will complete Week 12 
assessments and will also complete the Blinded Study follow-up visit 
4 weeks after their last dose if possible.  
Open-Label Extension (OLE) Phase
Subjects who do not permanently discontinue study drug and 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 11
09 February 2017
complete the Blinded Study Phase follow-up visit will be eligible to 
enter into the OLE Phase of the study for 96 weeks. Subjects will 
begin open-label treatment with GS-9674 (100 mg po once daily).  
The dose of GS-9674 may be reduced from 100 mg to 30 mg (or 
subsequently increased back to 100 mg) at the PI’s discretion with the 
approval of the Medical Monitor (MM), if required due to 
tolerability. In the OLE Phase, subjects will have in-clinic study 
assessments at OLE Baseline/Day 1, OLE Week 1, OLE Week 2, 
OLE Week 4, OLE Week 8, OLE Week 12, and every 12 weeks 
thereafter for symptom-driven PE, vital signs, laboratory assessments, 
urine pregnancy tests (for females of childbearing potential at OLE 
Baseline/Day 1 and every 4 weeks thereafter), urine, stool and blood 
collection for biomarker assessments (at OLE Baseline/Day 1, Weeks 
4, 12 and every 12 weeks thereafter), QoL (SF-36, PBC-40 and PSC-
PRO) at OLE Baseline/Day 1, Weeks 4, 12 and every 12 weeks 
thereafter) and pruritus questionnaires (Pruritus VAS and 5D-Itch), 
calculation of partial Mayo score (subjects with IBD), weight, and 
review of AEs and CMs.
Subjects in the OLE Phase will the complete treatment Week 96 visit 
and then return for their final visit, the OLE follow up visit 4 weeks 
following the last dose of study drug. Subjects who prematurely 
discontinue participation in the OLE Phase will complete the Week 
96 assessments and will also complete the follow-up visit 4 weeks 
after their last dose if possible.  
At the OLE follow up visit, subjects will have a symptom-driven PE, 
measurement of vital signs, review of AEs, CMs, pruritus and 
assessment and serum will be drawn for hematology, blood 
chemistry, lipids, and a coagulation panel. A urine pregnancy test will 
be performed for females of childbearing potential only.
Test Product: 
GS-9674 30 mg tablet administered orally once daily with food.
GS-9674 100 mg tablet administered orally once daily with food.
Reference Product:
Placebo-to-match (PTM) GS-9674 30 mg tablet administered orally 
once daily with food.
Placebo-to-match (PTM) GS-9674 100 mg tablet administered orally 
once daily with food.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 12
09 February 2017
Dose and Mode of 
Administration:

Treatment Group A: GS-9674 30 mg (1 x 30 mg tablet) + PTM 
GS-9674 100 mg (1 x PTM 100 mg tablet) administered orally 
once daily with food.

Treatment Group B: GS-9674 100 mg (1 x 100 mg tablet) + 
PTM GS-9674 30 mg (1 x PTM 30 mg tablet) administered orally 
once daily with food.
Treatment Group C: PTM GS-9674 30 mg (1 x PTM 30 mg 
tablet) + PTM GS-9674 100 mg (1 x PTM 100  mg tablet) 
administered orally once daily with food.
Criteria for 
Evaluation:
Safety:
The primary endpoint is the safety of GS-9674 in subjects with PSC
without cirrhosis.
Safety will be assessed during the study through the reporting of AEs, 
and by clinical laboratory tests and vital sign assessments at various 
time points during the study. Concomitant medication usage will also 
be assessed throughout the study.
An independent, external Data Monitoring Committee (DMC) that 
consists of two hepatologists and a PhD statistician will convene once 
20 subjects have been randomized and every 3 to 4 months thereafter 
to monitor the study for safety events in the Blinded Study Phase and 
every 6 months in the OLE Phase. The DMC will meet on an ad hoc 
basis if there are at least 3 similar Grade ≥ 3 serious, treatment related 
Common Terminology Criteria for Adverse Events (CTCAE) 
observed in the study. In the event of two similar treatment-related 
Grade 4 CTCAE events or one treatment-related Grade 5 CTCAE, 
the DMC will review the data and advise the sponsor regarding 
stopping or continuing the study.
Efficacy:
Efficacy will be assessed through a number of exploratory endpoints. 
These exploratory endpoints are described in Section 8.1.3.
Pharmacokinetic and 
Pharmacodynamic:
Plasma concentrations of GS-9674, GS-716070 (metabolite of 
GS-9674), and other metabolites as appropriate, will be determined 
for PK analyses as applicable. Plasma or serum concentrations of 
FGF19, C4, and bile acids will be determined as applicable for PD 
analyses.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Statistical Methods: 
Safety Analysis: 
Efficacy Analysis: 
Exploratory 
Analysis: 
Sample Size: 
All safety data collected will be listed and summarized, as 
appropriate, by treatment group. 
Final 
Amendment 3 
The biological and histological activity of study drugs will be 
evaluated using histologic endiJoints and biomarker variables. 
PPD 
PPD 
Due to the exploratory nature of this study, no formal power 
calculations were used to determine sample size. The number of 
subjects was chosen based on clinical experience with other similar 
proof of concept studies. 
This study will be conducted in accordance with the guidelines of Good Clinical Practice (GCP) 
including archiving of essential documents. 
CONFIDENTIAL 
Page 13 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 14
09 February 2017
GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS
C 
degrees Celsius
F
degrees Fahrenheit
AE
adverse event
ALT
alanine aminotransferase
ALP
alkaline phosphatase
ATV
atorvastatin
AMA
anti-mitochondrial antibodies
Apo B
apolipoprotein B
aPTT
activated partial thromboplastine time
AST
aspartate aminotransferase
ATP
Adenosine triphosphate
AUC
area under the plasma/serum/peripheral blood mononuclear cell concentration 
versus time curve
-hCG
beta human chorionic gonadotropin
BAP
Biomarker Analysis Plan
BCRP
breast cancer resistance protein
BUN
blood urea nitrogen
BW
body weight
C4
7-alpha-hydroxy-4-cholesten-3-one
CFR
code of federal regulations
Clast
last observed quantifiable plasma/serum concentration of the drug
Cmax
maximum observed plasma/serum concentration of drug
CMs
concomitant medications
CNS
central nervous system
CRO
contract (or clinical) research organization 
CsA
cyclosporine
CSR
Clinical Study Report
CTCAE
Common Terminology Criteria for Adverse Events
DAB
metabolite of dabigatran etexilate
DDI
drug-drug interaction
DE
dabigatran etexilate
CYP3A
cytochrome P4503A
CV
cardiovascular
DILI
drug induced liver injury
DMC
Data Monitoring Committee
DNA
deoxyribonucleic acid
DSPH
Drug Safety and Public Health
EC50
Concentration of drug that gives half-maximum response

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 15
09 February 2017
ECG
electrocardiogram
ET
early terminated
eCRF
electronic case report form
EDC
electronic data capture
e.g.
example
ELF™Test
enhanced liver fibrosis test
ERCP
endoscopic retrograde cholangiopancreatography
EU
European Union
FAS
Full analysis set
FDA
(United States) Food and Drug Administration
FSH
Follicle-stimulating hormone
FGF
Fibroblast growth factor
FXR
Farnesoid X Receptor
GCP
good clinical practice
GCSF
granulocyte colony stimulating factor
GFZ
gemfibrozil
GGT
gamma glutamyl transferase
GSI
Gilead Sciences, Inc.
HbA1c
Hemoglobin A1c
HBsAg
Hepatitis B surface antigen
HBV
Hepatitis B virus
Hct
Hematocrit
HDPE
High-density polyethylene
HCV
Hepatitis c virus
Hg
Hemoglobin
HIV
Human immunodeficiency virus
HLT
high-level term
HLGT
high-level group term
HMG-CoA
3-hydroxy-3-methylglutaryl-coenzyme A
HOMA-IR
homeostatic assessment of insulin resistance
IB
investigator’s brochure
IBD
inflammatory bowel disease
ICF
Informed Consent Form
ICH
International Conference on Harmonisation of Technical Requirements for 
Registration of Pharmaceuticals for Human Use
IEC
independent ethics committee
IMP
Investigational Medicinal Product
IND
Investigational New Drug (Application)
INR
international normalized ratio
IRB
institutional review board

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 16
09 February 2017
IUD
intrauterine device
IWRS
interactive web response system
kg
Kilogram
LDH
lactate dehydrogenase
LLT
lower-level term
MedDRA
Medical Dictionary for Regulatory Activities
g
Microgram
MDZ
midazolam
mg
Milligram
min
Minute
mL
Milliliter
mm
Millimeter
mm Hg
millimeters of mercury
MM
Medical Monitor
MRCP
Magnetic Resonance Cholangiopancreatography
MRE
Magnetic Resonance Elastography
NAFLD
non-alcoholic fatty liver disease
NASH
non-alcoholic steatohepatitis
NTCP
sodium-taurocholate cotransporting polypeptide
NMR
nuclear magnetic resonance spectroscopy
NOAEL
no observed adverse event level
OATP
Organic anion-transporting polypeptide
OLE
Open Label Extension
PRA
pravastatin
PBC
Primary Biliary Cholangitis
PBMCs
peripheral blood mononuclear cell(s)
PD
Pharmacodynamic
PK
Pharmacokinetic
P-gp
P-glycoprotein
PO
taken by mouth
PRA
pravastatin
PRO
Patient –Reported Outcome
PSC
Primary Sclerosing Cholangitis
PT
preferred term
PTC
percutaneous transhepatic cholangiogram
PT
prothrombin time
PTT
Partial prothrombin time
QoL
Quality of Life
RBC
red blood cell count
RIF
rifampin

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 17
09 February 2017
RNA
ribonucleic acid
RXR
Retinoid X receptor
SADR
serious adverse drug reaction
SAE
serious adverse event
SAP
statistical analysis plan
SD
standard deviation
SF-36
Short Form (36) Health Survey
SOC
System Organ Class
SOP
standard operating procedure
SUSAR
Suspected Unexpected Serious Adverse Reaction
t½
Time required for the terminal elimination half-life of the drug
TEAEs
Treatment emergent adverse events
TGR5
bile acid receptor
TPO
thrombopoietin
TR-FRET
Time-resolved fluorescence resonance energy transfer
Tlast
last measured concentration
Tmax
time (observed time point) of Cmax
TNF
tumor necrosis factor
UDCA
ursodeoxycholic acid
UGT
uridine dophosphate glucuronosyltransferase
ULN
upper limit of the normal range
US
United States
USPI
United States product insert
Vss
Volume of distribution at steady state
VAS
visual analog scale
VORI
voriconazole
WBC
white blood cell count

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 18
09 February 2017
1.
INTRODUCTION
1.1.
Background
Primary Sclerosing Cholangitis (PSC) is a chronic biliary disease of unknown etiology 
characterized by a fibrosing cholangitis that leads to inflammation, cholestasis and cirrhosis. The 
overall incidence of PSC is 0.77 per 100,000 person-years, with a median age at diagnosis of 
41 years and 2-to-1 male to female predominance {Molodecky 2011}. PSC is highly associated 
with inflammatory bowel disease (IBD), typically ulcerative colitis (UC) with up to 90% of PSC 
patients having associated IBD and conversely, PSC develops in approximately 8% of all IBD 
patients {Saich 2008}. There are approximately 30,000-45,000 patients with PSC in the United 
States, making it an orphan disease. PSC affects less than 1.6 in 10,000 people in the European 
Union (EU), equivalent to a total of fewer than 82,000 people. 
PSC is a progressive disease that leads to cirrhosis of the liver. The clinical presentation of PSC 
is variable, and ranges from asymptomatic disease with mild elevations in alkaline phosphatase 
(ALP) and transaminases to more rapidly progressive, symptomatic disease in 15-30% of all 
patients. In addition to complications related to cirrhosis and portal hypertension, patients with 
PSC are prone to repeated episodes of bacterial cholangitis, pruritus, and are at high risk for 
cholangiocarcinoma. Specifically, the lifetime risk of cholangiocarcinoma in patients with PSC 
is 10-15%, a rate 160-fold that of the general population {Saich 2008}. Mortality from PSC is 
estimated to be 35% over 10 years from diagnosis {Kornfeld 1997}.
There are no approved therapies for PSC. Medical therapy with ursodeoxycholic acid (UDCA) 
may improve liver biochemistry, but has no impact on symptoms or clinical outcomes {Triantos 
2011}. Immunosuppressive therapy has also been ineffective {Lindor 2015}. Episodes of 
ascending cholangitis are managed supportively with antibiotics in conjunction with therapeutic 
drainage if necessary. Liver transplantation is the only therapeutic option currently available to 
patients with PSC. Outcomes of transplantation are generally favorable (five-year survival 
~85%), but the disease recurs post-transplant in up to 25% of patients {Graziadei 1999}.
The etiology of PSC is unknown. As noted above, there is a strong association with IBD and 
genome-wide association studies (GWAS) indicate moderate genetic associations with PSC. The 
strongest associations are in the HLA complex on chromosome 6p21 with weaker associations at 
loci known to be associated with IBD, chromosome 3p21, 2q35 and the GPC5/GPC6 region on 
chromosome 13q31 {Karlsen 2010}. Several hypotheses as to the underlying cause of the 
disease have been proposed including aberrant homing of T cells to the bile ducts, autoimmunity, 
bile acid toxicity, and gut bacterial translocation leading to fibrosing cholangitis, and subsequent 
cholestasis and hepatotoxicity.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 19
09 February 2017
1.2.
GS-9674
1.2.1.
General Information
GS-9674 is a potent agonist of Farnesoid X Receptor (FXR) whose activity in intestinal 
epithelial cells results in the release of fibroblast growth factor 19 (FGF19). FGF19 is an 
endocrine peptide which drives a signaling cascade to decrease hepatic lipogenesis, 
gluconeogenesis, triglyceride accumulation, and bile acid synthesis.
Please refer to the Investigator’s Brochure (IB) for additional information on GS-9674 including:

In Vitro FXR agonism

Nonclinical Pharmacokinetics and In Vitro Metabolism

Nonclinical Pharmacology and Toxicology
1.2.2.
Nonclinical Toxicology
The nonclinical toxicity profile of GS-9674 has been assessed in mice and cynomolgus monkeys 
administered GS-9674 orally for up to 26 and 39 weeks, respectively. GS-9674-related effects 
were primarily limited to non-adverse findings in the liver for both species that are likely related 
to the pharmacology of the compound. Mild increases in alkaline phosphatase (ALP) activity and 
liver weights were observed in the 4 week and chronic (26 or 39 weeks) studies. In the 4-week 
studies and 26-week mouse study, these findings were associated with hepatocellular 
hypertrophy (both species) and minimal oval cell hyperplasia (monkeys). In the chronic monkey 
study, there were no correlating histological changes in the liver after 39 weeks of dosing. The 
above findings were observed at ≥100 mg/kg/day after 4 weeks of dosing and at all doses (≥ 20 
mg/kg/day) after 26 weeks of dosing in mice. In monkeys, the above findings were observed at 
doses of 300 mg/kg/day after both 4 and 39 weeks of dosing. The decreases in cholesterol 
(≥60 mg/kg/day) and triglycerides (≥100 mg/kg/day) as well as increased albumin 
(≥60 mg/kg/day) observed in mice after 4 and/or 26 weeks of dosing as well as the decrease in 
serum bile acids (300 mg/kg/day) in monkeys 39 weeks of dosing are also likely to be related to 
the pharmacology of GS-9674. Other minimal to mild, non-adverse findings observed after 26 or 
39 weeks of dosing in mice or monkeys, respectively, that were considered GS-9674-related 
included decreased red blood cell parameters (mouse; ≥20 mg/kg/day), increased platelets 
(mouse; 600/300 mg/kg/day), shortened activated partial thromboplastin time (monkey; 300 
mg/kg/day), and increased phosphorus (mouse; 600/300 mg/kg/day). All findings showed 
evidence of reversibility after a 4-week recovery period. The no-observed-adverse effect levels 
(NOAEL) in mice after 26 weeks of dosing and in monkeys after 39 weeks of dosing were 60 
and 300 mg/kg/day, respectively. 
Preliminary PK data from Cohort 5 (administration of GS-9674 100 mg with food) in the 
ongoing Phase 1 study of GS-9674 (GS-US-402-1851, included in IB) indicate adequate safety 
margins based on GS-9674 exposures at the nonclinical NOAEL doses in mouse and 
cynomolgus monkey (Table 1-1).

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 20
09 February 2017
Table 1-1.
Exposure Margins for GS-9674 Based on Observed GS-9674 
Exposure After Administration of 100 mg GS-9674 Under Fed
Conditions in Cohort 5 Compared to Exposures Observed at NOAEL 
Doses in Mouse and Cynomolgus Monkey 
Species
NOAEL
Exposure Margina
Dose 
mg/kg/day
AUCtau
µg*hr/mL
Mouse
60
Male: 66
Female: 110
Male: 13
Female: 22
Cynomolgus Monkey
300
163
32
a
Calculated using observed human AUCinf of 5.02 µg*hr/mL at 100 mg QD dose administered fed from cohort 5 in 
Study GS-US-402-1851.
1.2.3.
Nonclinical Pharmacology
GS-9674 is a potent and selective agonist of FXR. This conclusion is supported by the following 
data: 1) modeling demonstrated an interaction of GS-9674 with the binding domain of FXR/
Retinoid X receptor (RXR) consistent with agonist activity, 2) GS-9674 induced an agonist 
response in a time-resolved fluorescence resonance energy transfer (TR-FRET) biochemical 
assay with an EC50 of 16 nM, which was comparable to that of other known FXR agonists, and 
3) GS-9674 did not activate the structurally similar bile acid receptor TGR5, did not activate 
other nuclear hormone receptors, and did not bind to a panel of other off-target receptors and 
enzymes.
The cellular potency of GS-9674 to activate FXR-mediated transcription was characterized using 
a firefly luciferase reporter gene engineered under the control of a FXR/RXR response element 
(PC-402-2012). GS-9674 caused complete FXR activation with an EC50 value of 43 nM, which 
was more potent than chenodeoxycholic acid (EC50 of 1770 nM).
Oral dose-ranging experiments in male cynomolgus monkeys demonstrated maximal increases in 
plasma FGF19 at a dose of 5 mg/kg (PC-402-2016). In addition, the oral administration of 
GS-9674 (30 mg/kg) to cynomolgus monkeys directly activated intestinal FXR, as measured by 
the expression of FXR-target genes in the ileum (15-fold increase in FGF19 mRNA, and a 2-fold 
increase in organic solute transporter (OSTα and OSTβ mRNA) (PC-402-2005).
The effects of GS-9674 on FGF19 levels were compared in cynomolgus monkeys following both 
oral and intravenous (IV) administration (PC-402-2016). Despite greater exposures following IV 
administration, only the oral administration of GS-9674 increased circulating FGF19 levels. 
These data suggest that intestinal FXR agonism by GS-9674 causes FGF19 production, whereas 
low systemic free drug concentrations limit effects following IV administration of GS-9674.
GS-9674 was evaluated in a choline-deficient high fat diet/NaNO2 rat model of liver fibrosis 
(PC-402-2015). This in vivo model utilized “2 hits” to mimic the metabolic and oxidative stress 
components of NASH disease in humans {Nakamoto 2009}, {Murakami 2013}. Treatment with

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Final 
Amendment 3 
GS-9674 dose-dependently reduced both biochemical and histological measures of liver fibrosis 
in this model. 
Safety pharmacology studies have been conducted to examine the potential effects ofGS-9674 
on the cardiovascular (CV), respiratory, and central nervous system (CNS) systems. There were 
no GS-9674-related effects on the CNS or respiratory system in mice administered up to 
600 mg/kg. In addition, there was no significant human ether-a-go-go-related gene inhibition at 
concentrations up to 100 J..LM or GS-9674-related effects on the CV system in monkeys 
administered up to 300 mg/kg. 
Overall, the results from these pharmacology studies demonstrate that GS-9674 is a potent and 
selective agonist of intestinal FXR with the potential to benefit patients with PSC by inducing 
FGF19 production and reducing bile acid levels. 
1.2.4. 
Non clinical Pharmacokinetics 
when dosed as 
pH-dependents 
GS-9674 absorption. 
10% and 20% 
. Low, 
limiting 
The low systemic clearance (CL) of GS-9674 in rats, dogs and monkeys was considerably lower 
than the predicted hepatic clearance based on in vitro studies with hepatocytes. This discrepancy 
is most likely a result of protein-restricted clearance in vivo due to the very high plasma protein 
binding(> 99.6%) across species. The volume of distribution (V ss) ofGS-9674 was consistent 
with extracellular fluid (ranging from 0.16-0.21 Llkg) in rats, dogs, and monkeys. 
After oral dosing to albino and pigmented mice, e
4C] GS-9674-derived radioactivity was 
distributed to most of the tissues, with the highest maximum concentrations of radioactivity 
determined in organs of absorption and excretion. Generally similar distribution patterns and 
tissue concentrations of e4C]GS-9674-derived radioactivity were observed in albino and 
pigmented mice with no observed binding to melanin. In both strains, no quantifiable 
radioactivity was detected in brain, suggesting [14C] GS-9674-derived radioactivity did not cross 
the blood-brain barrier. Fecal elimination was a predominant route of elimination of [14C] 
GS-9674-derived radioactivity in both mice (85.7% and 5.45% recovered in feces and urine, 
respectively) and monkeys (78.2% and 69.7% recovered in feces in intact and bile duct 
cannulated animals) likely representing drug not absorbed from the gastrointestinal tract. 
Approximately 6% of the administered radioactivity was excreted in bile and urine in monkeys. 
Radiolabeled material was primarily excreted within the first 48 hours. 
GS-9674 undergoes oxidative metabolism in human hepatocytes. Comparison of metabolism in 
hepatocytes from mice, rats, dogs, monkeys, and humans did not identify any metabolites unique 
to humans, supporting the selection of mice and monkeys for the assessment of the toxicology of 
GS-9674. Of the recombinant human CYP isozymes tested, CYP2C8, CYP3A4, and CYP2C19 
were shown to metabolize GS-9674. Potent inhibitors ofthese CYPs therefore may affect 
metabolism ofGS-9674. GS-9674 had little inhibitory effect on the activities ofCYP1A2, 
CONFIDENTIAL 
Page 21 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 22
09 February 2017
CYP2B6, CYP2C19 or CYP2D6 (IC50 > 25 μM). For CYP2C8, CYP2C9, and CYP3A, IC50
values of 2.4 to 13.6 μM were obtained but GS-9674 was not a mechanism-based inhibitor of 
these enzymes. GS-9674 showed moderate inhibition of human UGT1A1, sodium-taurocholate 
cotransporting polypeptide (NTCP), and bile salt export pump (IC50 2.8-7.7 μM). GS-9674 
inhibited human OATP1B1, OATP1B3, and OATP2B1 with IC50 values of 0.68, 0.41, and 
0.21 μM, respectively. GS-9674 therefore has the potential to affect hepatic/intestinal uptake of 
OATP substrates or metabolism of CYP2C8, CYP2C9, or CYP3A4 substrates when its 
concentrations are sufficiently high. However, low solubility, high protein binding (> 99.98%) 
and low systemic levels reduce the potential for GS-9674 to cause drug-drug interactions via 
inhibition of metabolic enzymes and transporters.
GS-9674 was a substrate for efflux transporters P-glycoprotein and breast cancer resistance 
protein, as well as the uptake transporters OATP1B1, 1B3, and 2B1, and NTCP. Inhibitors or 
genetic polymorphisms affecting the activity of these transporters may affect GS-9674 intestinal 
absorption and hepatic uptake. This was illustrated in an in vivo study in monkeys where 
pretreatment with Cyclosporin A, a known inhibitor of efflux transporters, increased the 
bioavailability of GS-9674 approximately 5-fold.
GS-9674 is highly selective for FXR over other nuclear hormone receptors in cell-based reporter 
assays, including those associated with potential for induction of human drug metabolizing 
enzymes and transporters (eg, pregnane X receptor, constitutive androstane receptor). Thus the 
liability of GS-9674 to cause drug-drug interactions through proteins regulated by these nuclear 
receptors is low.
1.2.5.
Clinical Trials of GS-9674
As of 23 Sept 2016, 4 Phase 1 clinical studies are ongoing (GS-US-402-1851, GS-US-402-3885, 
GS-US-402-2102, and GS-US-402-2101), and 4 Phase 2 studies in subjects with NAFLD, 
NASH, PBC, and PSC are ongoing or planned (GS-US-384-3914, GS-US-402-1852, 
GS-US-427-4024, and GS-US-428-4025, respectively). These Phase 1 and 2 studies are
described in the IB.
A brief summary of preliminary results, not included in the IB from ongoing study GS-US-402-
2102 is presented below.
1.2.5.1.
GS-US-402-2102
Study GS-US-402-2102 is an ongoing Phase 1, open-label, multicenter, multiple-cohort study 
designed to evaluate transporter and CYP-mediated drug-drug interactions (DDIs) between 
GS-9674 100 mg and various probe drugs in healthy subjects. A total of approximately 180 
subjects are planned to be enrolled.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 23
09 February 2017
Preliminary PK results from the following cohorts are presented below and in Table 1-2 and 
Table 1-3:

Cohort 1: Impact of OATP/MRP2/P-gp inhibition (single dose cyclosporine 600 mg: CsA) or 
OATP1B1/1B3 inhibition (single dose rifampin 600 mg: RIF) on single dose administration 
of GS-9674 100 mg with food (N=24).  Single doses of CsA or RIF significantly increased 
GS-9674 exposure (6.5- and 8.0-fold respectively), with more modest increases in 
GS-716070 exposure (3.3- and 4.9-fold respectively). These data indicate the GS-9674 is a 
sensitive substrate of hepatic OATP with intestinal P-gp playing a minimal to no role in 
GS-9674 absorption as seen by a smaller increase in GS-9674 by CsA compared to single 
dose RIF.  Based on these data, coadministration of GS-9674 with potent inhibitors of OATP 
is not recommended and moderate inhibitors of OATP should be used with caution whereas 
GS-9674 may be coadministered with P-gp inhibitors.

Cohort 2: Impact of CYP3A inhibition (multiple dose voriconazole 200 mg BID 4 days: 
VORI) and CYP2C8 inhibition (multiple dose gemfibrozil 600 mg BID 4 days: GFZ) on 
single dose administration of GS-9674 100 mg with food (N=18).  Coadministration of 
GS-9674 with VORI did not result in clinically meaningful changes in GS-9674 or 
GS-716070 exposures indicating that CYP3A plays a minimal role in the disposition of 
GS-9674 and GS-716070.  As such, GS-9674 may be coadministered with CYP3A 
inhibitors. Coadministration of GS-9674 with GFZ increased GS-9674 exposure 75% with 
reduction of GS-716070 exposure by 55% indicating that biotransformation of GS-9674 to 
GS-716070 is predominantly mediated by CYP2C8.  Based on the less than 2-fold increase 
in GS-9674 exposure, GS-9674 may be coadministered with inhibitors of CYP2C8.

Cohort 3: Impact of CYP3A/2C8/OATP/P-gp induction (multiple dose rifampin 600 mg QD 
7 days in the evening: RIF) on single dose AM administration of GS-9674 100 mg with food
(N=18).  Plasma exposure of GS-9674 and GS-716070 were substantially reduced after 
multiple dose administration of RIF indicating that GS-9674 and GS-716070 are sensitive to 
induction of OATP and CYP2C8.  As such coadministration of GS-9674 with potent or 
moderate inducers of OATP or CYP2C8 is not recommended.

Cohort 5: Impact of single dose administration of GS-9674 100 mg with food on CYP3A 
activity (single dose midazolam: MDZ) or OATP/CYP3A activity (single dose atorvastatin: 
ATV) (N=24).  GS-9674 did not alter MDZ exposure (90%CIs of the %GMR for AUC and 
Cmax were contained within the predetermined lack of effect bounds of 70-143%) indicating 
that GS-9674 is not an inhibitor of CYP3A. As such, GS-9674 may be coadministered with 
CYP3A substrates.  GS-9674 modestly increased ATV exposure (39%).  Similar increases in 
ATV exposure do not necessitate a priori dose modification as per the LIPITOR® United 
States product insert (USPI). As such, ATV may be coadministered with GS-9674.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 24
09 February 2017

Cohort 6: Impact of single dose administration of GS-9674 100 mg with food on P-gp (single 
dose dabigatran etexilate 75 mg: DE), OATP (single dose pravastatin 40 mg: PRA) or 
OATP/BCRP (single dose rosuvastatin 10 mg: ROS) (N=24). GS-9674 did not alter DE (free 
or total dabigatran: DAB metabolite of DE), PRA, or ROS exposures (90%CIs of the %GMR 
for AUC and Cmax were contained within the predetermined lack of effect bounds of 
70-143%) indicating the GS-9674 is not an inhibitor of P-gp, OATP, or BCRP.  As such,
GS-9674 may be coadministered with P-gp, OATP, or BCRP substrates.
Table 1-2.
Preliminary Pharmacokinetic Results from Study GS-US-402-2102 
Evaluating the Effect of DDIs on Administration of 100 mg GS-9674 
with Food (Cohorts 1-3)
%GMR (90%CI) Test/Reference
Cohort 1 (N=24)
Cohort 2 (N=18)
Cohort 3 (N=18)
Analyte
PK 
Parameter
CsA
RIFa
VORI
GFZ
RIFb
GS-9674
AUCinf
655 
(577, 743)
796
(719, 880)
95.9
(81.0, 114)
175
(149, 206)
32.8
(27.9, 38.4)
Cmax
512
(448, 584)
547
(497, 603)
76.8
(60.2, 97.9)
139
(115, 168)
35.5
(29.1, 43.3)
GS-716070
AUCinf
331
(297, 369)
493
(442, 551)
129
(109, 154)
44.5
(38.7, 51.1)
12.6
(10.5, 15.0)
Cmax
211
(191, 232)
301
(274, 331)
99.2
(81.1, 121)
31.2
(26.1, 37.4)
17.0
(13.7, 21.2)
Data are presented to 3 significant digits
a
Single Dose
b
Multiple Dose

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 25
09 February 2017
Table 1-3.
Preliminary Pharmacokinetic Results from Study GS-US-402-2102 
Evaluating the Effect of GS-9674 100 mg with Food on CYP3A, 
OATP/CYP3A, P-gp, OATP, or OATP/BCRP (Cohorts 5-6)
Cohort
Enzyme/ 
Transporter
Analyte
PK Parameter
Test
Reference
% GMR 
(90%CI) 
Test/Reference
5 
(N=24)
CYP3A
MDZ
AUCinf 
37.3 (27.5)
63.9 (29.1)
102 (95.8, 108)
Cmax 
7.79 (27.6)
7.92 (35.6)
100 (94.8, 106)
OATP/
CYP3A
ATV
AUCinf 
15.5 (33.5)
10.8 (39.0)
139 (124, 156)
Cmax 
1.06 (35.6)
0.98 (35.9)
107 (94.6, 120)
6
(N=24)
P-gp
Total 
DAB
AUCinf 
624 (32.0)
535 (34.3)
118 (109, 128)
Cmax 
84.4 (40.0)
68.0 (37.8)
125 (112, 139)
Free 
DAB
AUCinf 
543 (32.0)
477 (37.3)
116 (108, 124)
Cmax 
75.0 (39.6)
60.8 (42.5)
125 (114, 138)
OATP
PRA
AUCinf 
109 (55.6)
99.6 (66.7)
115 (104, 126)
Cmax 
41.7 (58.8)
42.4 (66.5)
104 (91.5, 117)
OATP/ 
BCRP
ROS
AUCinf 
38.3 (40.3)
34.9 (39.5)
111 (101, 121)
Cmax 
3.06 (40.4)
2.86 (43.4)
108 (98.3, 119)
Data are presented as mean (%CV) to three significant digits
1.3.
Rationale for this Study
PSC is a disorder of unknown etiology characterized by inflammation and fibrosis of the 
intrahepatic and/or extrahepatic bile ducts that result in the impairment of bile flow (cholestasis). 
Accumulation of excess bile acids causes hepatocellular cytotoxicity that leads to progressive 
liver fibrosis and cirrhosis. In pre-clinical and clinical studies, FXR agonism has been shown to 
reduce bile acid levels via FGF19-mediated suppression of cholesterol-7-alpha-hydroxylase 
(CYP7A1), the rate-limiting enzyme in bile acid biosynthesis {Inagaki 2005}, {Pellicciari 2002}, 
{Mudaliar 2013}. In addition, in a murine model of fibrosis caused by administration of a 
methionine choline deficient diet and sodium nitrite injections, GS-9674 has demonstrated an 
anti-fibrotic effect. Thus, GS-9674 is postulated to be beneficial in subjects with PSC.  
This study will evaluate the safety, tolerability, and efficacy of 30 mg and 100 mg GS-9674 
administered with food for 12 weeks in subjects with PSC. The doses were selected based on 
short-term safety, PD and PK results from Study GS-US-402-1851 in healthy subjects. 
Across the range of GS-9674 doses evaluated (10 to 300 mg QD), doses > 30 mg provide 
comparable intestinal FXR agonism assessed by increases in plasma FGF19 exposure. Food, by 
slowing oral absorption of GS-9674, results in prolonged elevation of plasma FGF19 
concentrations. Exposure-response relationships show that changes in C4 exposure are 
negatively correlated with changes in FGF19 exposure as well as GS-9674 exposure. Based on 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 26
09 February 2017
these results, GS-9674 doses of 30 and 100 mg with food are selected for further study as they 
are expected to 1) provide enteral FXR agonism, reductions in bile acid pools, and liver 
biochemical improvements in subjects with PSC; and 2) inform regarding the impact of 
increasing systemic GS-9674 exposure on safety and efficacy.
In the Phase 1 study, GS-US-402-1851, GS-9674 was tested at doses up to 300 mg once daily for 
up to 14 days and was well-tolerated. Taken together, these data support the evaluation of 
GS-9674 30 and 100 mg in subjects with PSC.
Inclusion criteria for this study were developed in order to identify subjects with PSC who have 
persistently abnormal liver biochemistry but without cirrhosis. These subjects are at an increased 
risk of PSC-related complications including the need for liver transplantation and death. Subjects 
with clinical and histologic evidence of cirrhosis will be excluded from this study due to the 
uncertain PK and PD properties of GS-9674 to the setting of subjects with cirrhosis. Targeting 
interventions in the proposed study population will provide evidence for the safety and efficacy 
of GS-9674 in subjects at risk for progressive hepatic fibrosis and cirrhosis.
1.4.
Risk/Benefit Assessment for the Study
This study will provide information on the safety and efficacy of GS-9674 for the treatment of 
patients with PSC. It should be noted that there are no currently approved therapies specifically 
for the treatment of PSC. The only therapeutic option available to PSC subjects with advanced 
liver disease is liver transplantation.
The potential benefits of GS-9674 for the treatment of PSC in the current study population 
include hypothesized improvements in hepatic injury due to reduced bile acid synthesis 
attributable to FXR agonism. Improvements in liver biochemistry, hepatic fibrogenesis, and 
potentially quality of life, would be expected to ensue based on these effects. Subjects with PSC 
randomized to the placebo control arm in the study may benefit from frequent medical 
monitoring and close assessment of their PSC and associated pathologies during the duration of 
placebo treatment. Moreover, all subjects, including those treated with placebo during the 
randomized phase, will have the opportunity to receive GS-9674 treatment during a long-term 
open-label extension phase.
In the Phase 1 study, 94 subjects have received GS-9674 in single or multiple doses (14 days) up 
to 300 mg. All treatment emergent adverse events (TEAEs) were mild to moderate (Grade 1 or 
2), and overall, the rate of any adverse events (AEs) was similar between subjects treated with 
GS-9674 or placebo. The predominant toxicities were anemia, back pain, diarrhea, and headache. 
Grade 2 or 3 elevations in serum ALT were seen in five (5%) GS-9674 treated subjects and one 
(4%) placebo treated subject. Grade 2 or 3 ALT elevations that occurred on-treatment were 
observed in 2/23 (9%) BID treated subjects, but none of the 71 subjects who received once daily 
(QD) GS-9674 dosing. In these cases, elevations in serum bilirubin or prolongation of INR were 
not observed, serum ALT levels normalized upon treatment cessation, and no evidence of drug 
hypersensitivity syndrome (e.g., fever, rash, eosinophilia) was noted. In nonclinical studies, 
effects on the liver have been limited to non-adverse mild increases in alkaline phosphatase and 
liver weights and minimal hepatocellular hypertrophy that are likely a pharmacological response 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 27
09 February 2017
to FXR agonism. There were no elevations in liver transaminases or changes in liver pathology 
(degeneration/necrosis) in the nonclinical studies to suggest direct cellular damage. In order to 
mitigate the potential risk of hepatotoxicity with GS-9674, QD dosing of GS-9674 has been 
chosen for this study. Moreover, close monitoring of liver biochemistry values will be performed 
and parameters for discontinuation of the study drugs due to liver test abnormalities have been 
defined (see Section 7.5, Toxicity Management: Observation for Drug-Induced Liver Injury) and 
will be closely followed.
Additional risks to study subjects include those attributable to study participation in general, 
including risks associated with frequent clinic visits and laboratory blood draws, and the 
associated pain and discomfort of phlebotomy. Strategies to mitigate these risks include close 
monitoring of lab values as well as AEs. Parameters for discontinuation of the study drugs due to 
AEs and non-hepatic laboratory abnormalities are also defined and will be closely followed.
Overall, the nonclinical and limited preliminary clinical data show a positive benefit/risk ratio in 
support of the study in subjects with PSC.
1.5.
Compliance
This study will be conducted in compliance with this protocol, Good Clinical Practice (GCP), 
and all applicable regulatory requirements.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
2. 
OBJECTIVES 
The primary objective of this study is as follows: 
• 
To evaluate the safety and tolerability of GS-9674 in subjects with PSC 
The exploratory objectives ofthis study are as follows: 
IT 
I 
I 
I 
I 
I 
I 
I 
I 
I 
CONFIDENTIAL 
Page 28 
-
Final 
Amendment 3 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 29
09 February 2017
3.
STUDY DESIGN
3.1.
Study Design
This is a Phase 2 randomized, double-blind, placebo-controlled study evaluating the safety, 
tolerability, and efficacy of GS-9674 in subjects with PSC without cirrhosis.
The study will consist of 2 phases, a Blinded Study Phase and an OLE Phase. 
Blinded Study Phase: Includes a 4-week screening period, 12-weeks of blinded treatment, and a 
Blinded Study Phase Follow up visit 4 weeks after completion of blinded treatment. 
Subjects completing the Blinded Study Phase without permanently discontinuing study drug will 
be eligible to participate in the OLE Phase of the study.
OLE Phase: Includes a 96-week OLE and an OLE Phase follow-up visit 4 weeks after 
completion of open label treatment.
The overall study design is presented graphically in Figure 3-1.
Figure 3-1.
Overall Study Design 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 30
09 February 2017
3.2.
Treatment Plan and Regimen
Subjects meeting the study’s entry criteria will be randomly assigned in a 2:2:1 ratio to 1 of 3 
different treatment groups during the Blinded Study Phase as shown in Figure 3-1. 
Randomization will be stratified by the presence or absence of UDCA use.
Study drug(s) will be administered for a total of 12 weeks from the Baseline/Day 1 visit during 
the Blinded Study Phase and 96 weeks during the OLE Phase. During the OLE Phase subjects 
will begin open-label treatment with GS-9674 (100 mg po daily). The dose of GS-9674 may be 
reduced from 100 mg to 30 mg (or subsequently increased back to 100 mg) at the PI’s discretion 
with the approval of the MM, as required.
Subjects will be unblinded to their Blinded Study Phase treatment assignment after the primary 
analysis has been completed, approximately 6 weeks after all subjects have completed the 
Blinded Study Phase.
Dosage and administration of the study drug(s) and reference product are described in 
Section 5.3.
3.3.
Biomarker Testing
3.3.1.
Biomarker Samples to Address the Study Objectives:
Biological specimens will be collected in this study as per the study procedures table
(Appendix 2) and will be used to evaluate the association of exploratory systemic biomarkers 
with study drug response, including efficacy and/or adverse events and to increase knowledge 
and understanding of the biology of PSC or related diseases such as Primary Biliary Cholangitis 
(PBC) and/or the validation of a companion diagnostic for PSC. Because biomarker science is a 
rapidly evolving area of investigation, and adverse events in particular are difficult to predict, it 
is not possible to specify prospectively all tests that will be done on the specimens provided.  The 
testing outlined is based upon the current state of scientific knowledge. It may be modified 
during or after the end of the study to remove tests no longer indicated and/or to add new tests 
based upon the growing state of art knowledge. Samples will be destroyed no later than 15 years 
after the end of the study.
Biomarker testing can include biomarkers that monitor auto-antibodies characteristic of PSC, and 
markers of bone metabolism. In addition biomarkers such as biochemicals, biological 
macromolecules, naturally occurring metabolites, and biomarkers of FXR activity (e.g. FGF19, 
C4 and bile acids) can also be determined.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
3.3.2. 
Biomarker Samples for Optional Future Research 
PPD 
3.3.3. 
Biomarker Samples for Optional Genomic Research 
PPD 
CONFIDENTIAL 
Page 31 
Final 
Amendment 3 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 32
09 February 2017
4.
SUBJECT POPULATION
4.1.
Number of Subjects and Subject Selection
This study will enroll approximately 50 adults, between 18-70 years old with non-cirrhotic PSC.
4.2.
Inclusion Criteria
Subjects must meet all of the following inclusion criteria to be eligible for participation in this 
study.
1) Males and females between 18-70 years of age; inclusive based on the date of the screening 
visit;
2) Willing and able to give informed consent prior to any study specific procedures being 
performed;
3) Diagnosis of PSC based on cholangiogram (magnetic resonance cholangiopancreatography 
[MRCP], endoscopic retrograde cholangiopancreatography [ERCP], or percutaneous 
transhepatic cholangiogram [PTC]) within the previous 12 months;
4) Serum ALP > 1.67 x ULN;
5) For subjects on UDCA, the dose of UDCA must have been stable for at least 12 months 
before screening through the end of the treatment. For subjects not on UDCA, no UDCA use 
for at least 12 month before screening through the end of the treatment;
6) For subjects being administered biologic treatments (eg, anti-tumor necrosis factor (TNF) or 
anti-integrin monoclonal antibodies), immunosuppressants or systemic corticosteroids, the 
dose must have been stable for at least 3 months prior to screening and anticipated to remain 
stable throughout the trial;
7) Screening FibroSURE/FibroTest® < 0.75, unless a historical liver biopsy within 12 months 
of screening does not reveal cirrhosis. In subjects with Gilbert’s syndrome or hemolysis, 
FibroSURE/FibroTest® will be calculated using direct bilirubin instead of total bilirubin.  
8) Platelet count ≥ 150,000/mm3;
9) Albumin ≥ 3.3 g/dL;
10) Serum creatinine ≤ ULN 
11) In subjects with a history of IBD, a colonoscopy within 6 months of screening must 
demonstrate no evidence of active IBD;

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 33
09 February 2017
12) Females of childbearing potential (as defined in Appendix 4) must have a negative serum 
pregnancy test at the Screening visit and a negative urine pregnancy test on the Baseline/Day 
1 visit prior to the first dose of study drug;
13) All female subjects of childbearing potential who engage in heterosexual intercourse must 
agree to use a highly effective method of contraception from the screening visit throughout 
the study period and for 30 days following the last dose of study drug(s) (see definition in 
Appendix 4);
14) Male subjects with female partners of childbearing potential must use condoms during 
treatment and for 90 days after the last dose of study drug(s);
15) Male subjects must agree to avoid sperm donation from Baseline/Day 1 visit throughout the 
study period and for 90 days after the last dose of study drug(s);
16) Female subjects must refrain from egg donation and in-vitro fertilization during treatment 
and until at least 30 days after the last dose of study drug(s);
17) Willing and able to comply with scheduled visits, drug administration plan, laboratory tests, 
liver biopsies, other study procedures, and study restrictions;
18) Must be able to read and complete QoL questionnaires independently.
4.3.
Exclusion Criteria
Subjects who meet any of the following exclusion criteria are not to be enrolled in this study.
1) Pregnant or lactating females; lactating females must agree to discontinue nursing before the 
study drug (s) is administered;
2) ALT > 10x ULN;
3) Total bilirubin > 2x ULN;
4) INR > 1.2 unless on anticoagulant therapy;
5) Cirrhosis of the liver as defined by any of the following:
a) Historical liver biopsy demonstrating stage 4 fibrosis (e.g. Ludwig stage 4 or Ishak stage 
≥5)
b) History of decompensated liver disease, including ascites, hepatic encephalopathy or 
variceal bleeding
c) Liver stiffness >14.4 kPa by FibroScan;
6) Small-duct PSC (histologic evidence of PSC with normal bile ducts on cholangiography);

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 34
09 February 2017
7) Other causes of liver disease including secondary sclerosing cholangitis and viral, metabolic, 
alcoholic, and other autoimmune conditions Subjects with hepatic steatosis may be included 
if there is no evidence of nonalcoholic steatohepatitis (NASH) in the opinion of the 
investigator or on liver biopsy;
8) Positive anti-mitochondrial antibody;
9) History of liver transplantation;
10) History of hepatocellular carcinoma or cholangiocarcinoma. If a dominant stricture is found, 
cholangiocarcinoma must be excluded prior to randomization;
11) Ascending cholangitis within 60 days of screening;
12) Presence of a percutaneous drain or bile duct stent;
13) Chronic hepatitis B (HBsAg positive);
14) Chronic hepatitis C (HCV antibody and RNA positive);
15) HIV Ab positive;
16) Current active IBD defined as a partial Mayo score of > 1 and/or a score in the Rectal 
Bleeding domain > 0;
17) Known hypercoagulable condition or history of venous or arterial thromboembolic disease;
18) Alcohol consumption greater than 21 oz/week for males or 14 oz/week for females 
(1oz/30mL of alcohol is present in 1 12oz/360mL beer, 1 4oz/120mL glass of wine, and a 1 
oz/30 mL measure of 40% proof alcohol);
19) History of intestinal resection or malabsorptive condition that may limit the absorption of 
GS-9674. Prior cholecystectomy and appendectomy are permitted;
20) Use of fibrates or obeticholic acid within 3 months prior to screening through the end of 
treatment;
21) Use of antibiotics (e.g., vancomycin, metronidazole, minocycline, etc.) for the treatment of 
PSC within 60 days of screening;
22) Positive urine screen for amphetamines, cocaine or opiates (i.e. heroin, morphine) at 
screening. Subjects on stable methadone or buprenorphine maintenance treatment for at least 
6 months prior to screening may be included in the study. Subjects with a positive urine drug 
screen due to prescription opioid-based medication are eligible if the prescription and 
diagnosis are reviewed and approved by the investigator;

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 35
09 February 2017
23) Unstable cardiovascular disease as defined by any of the following:
a) Unstable angina within 6 months prior to screening
b) Myocardial infarction, coronary artery bypass graft surgery or coronary angioplasty 
within 6 months prior to screening
c) Transient ischemic attack or cerebrovascular accident within 6 months prior to screening
d) Obstructive valvular heart disease or hypertrophic cardiomyopathy
e) Congestive heart failure;
24) Use of any prohibited concomitant medications as described in Section 5.5;
25) History of a malignancy within 5 years of screening with the following exceptions:
a) Adequately treated carcinoma in situ of the cervix
b) Adequately treated basal or squamous cell cancer or other localized non-melanoma skin 
cancer;
26) Any laboratory abnormality or condition that, in the investigator’s opinion, could adversely 
affect the safety of the subject or impair the assessment of study results;
27) Participation in another investigational study of a drug or device within 1 month prior or 
within 5 half-lives of the prior investigational agent (whichever is longer) prior to screening;
28) Concurrent participation in another therapeutic clinical study;
29) Known hypersensitivity to GS-9674, the metabolites, or formulation excipient;
30) Presence of any condition that could, in the opinion of the investigator, compromise the 
subject’s ability to participate in the study, such as history of substance abuse or a psychiatric
(including any subjects with a psychiatric hospital admission or emergency room visit in the 
2 years prior to screening) or medical condition;
31) Unavailable for follow-up assessment or concern for subject’s compliance with the protocol 
procedures.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
5. 
INVESTIGATIONAL MEDICINAL PRODUCTS 
5.1. 
Randomization, Blinding and Treatment Codes 
Final 
Amendment 3 
An Interactive Web Response System (IWRS) will be used for centralized randomization and 
treatment assignment. Randomization will be stratified by the presence or absence ofUDCA use. 
Investigative site personnel will obtain the subject's identification number and study drug 
assignment from the IWRS. Subjects and all personnel directly involved in the conduct of the 
study will be blinded to treatment assignment. 
Study drug(s) will be dispensed by the study pharmacist, or designee, in a blinded fashion to the 
subjects. 
5.1.1. 
Procedures for Breaking Treatment Codes 
In the event of a medical emergency where breaking the blind is required to provide medical care 
to the subject, the investigator may obtain treatment assignment directly from the IWRS system 
for that subject (refer to the Study Reference Binder for IWRS unblinding instructions). Gilead 
recommends but does not require that the investigator contact the Gilead 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 case report form/ electronic case report 
form ( eCRF), along with the date on which the treatment assignment was obtained. The 
investigator is requested to contact the Gilead medical monitor promptly in case of any treatment 
unblinding. 
Blinding of study treatment is critical to the integrity of this clinical trial and therefore, if a 
subject's treatment assignment is disclosed to the investigator, the subject will have study 
treatment discontinued. All subjects will be followed until study completion unless consent to do 
so is specifically withdrawn by the subject. 
Gilead Drug Safety and Public Health (DSPH) may independently unblind cases for expedited 
reporting of suspected unexpected serious adverse reactions (SUSARs ). 
5.2. 
Description and Handling ofGS-9674 and PTM GS-9674 
5.2.1. 
Formulation 
GS-9674 is supplied as 30 
contain GS-9674-02 
CONFIDENTIAL 
Page 36 
09 February 2017 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Final 
Amendment 3 
Placebo-to-match (PTM) GS-9674 tablets are identical in size, shape, color and appearance to 
their corresponding 
of active GS-9674 tablets. PTM GS-9674 tablets contain the 
followin · 
clients: 
5.2.2. 
Packaging and Labeling 
GS-9674 tablets and PTM GS-9674 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 with an induction-sealed, aluminum-faced liner. 
Study drug(s) to be distributed to centers in the US and other participating countries shall be 
labeled to meet applicable requirements ofthe United States Food and Drug Administration 
(FDA), EU Guideline to Good Manufacturing Practice - Annex 13 (Investigational Medicinal 
Products), and/or other local regulations. 
5.2.3. 
Storage and Handling 
Study drug GS-9674 and PTM GS-9674 tablets should be stored at controlled room temperature 
of25°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. To ensure the stability and proper 
identification, study drug(s) 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 GS-9674 tablets and PTM GS-9674 
tablets. 
5.3. 
Dosage and Administration of GS-967 4/PTM GS-967 4 
GS-9674 and PTM GS-9674 tablets will be provided by Gilead Sciences. In order to maintain the 
blind, each subject will be supplied with 2 bottles of tablets during the blinded phase of the trial. 
One bottle will contain GS-9674 30 mg or PTM GS-9674 30 mg; the second bottle will contain 
GS-9674 100 mg or PTM GS-9674 100 mg. Dosing for each treatment group will be as follows: 
• 
Treatment Group A: GS-9674 30 mg (1 x 30 mg tablet)+ PTM GS-9674 100 mg (1 x PTM 
100 mg tablet) administered orally once daily with food 
• 
Treatment Group B: GS-9674 100 mg (1 x 100 mg tablet)+ PTM GS-9674 30 mg (1 x 
PTM 30 mg tablet) administered orally once daily with food 
CONFIDENTIAL 
Page 37 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 38
09 February 2017

Treatment Group C: PTM GS-9674 30 mg (1 x PTM 30 mg tablet) + PTM GS-9674 
100 mg (1 x PTM 100 mg tablet) administered orally once daily with food
During the OLE Phase of the study, subjects will be provided with 100 mg bottles of GS-9674
only, unless reassigned to the 30 mg dose due to tolerability. The dose of GS-9674 may be 
reduced from 100 mg to 30 mg (or subsequently increased back to 100 mg) at the PI’s discretion 
with the approval of the MM, as required.
The study drug dose should be taken at approximately the same time each day with food.
A dose will be considered missed if the subject cannot take the dose within 12 hours of their 
regular dosing time. If a subject misses a dose, the subject should take their next dose at the 
regular dosing time.
5.4.
Prior and Concomitant Medications
Concomitant use of certain medications or herbal/natural supplements with study drug may result 
in PK and/or PD interactions resulting in increases or decreases in exposure of study drug(s) or 
these medications. 
Concomitant medications taken within 28 days of screening through the follow-up visit need to 
be recorded in the source documents and electronic Case Report Forms (eCRFs).
Subjects with co-morbid diseases requiring medication(s) must be taking the medication without 
a change in dose within 28 days of Baseline/Day 1.
GS-9674 increased atorvastatin exposure (39%) which does not necessitate a priori dose 
modification based on the LIPITOR USPI.  Subjects taking atorvastatin with GS-9674 should be 
monitored as per label recommendations.
5.5.
Prohibited Medications
The following medications are prohibited from 28 days prior to Baseline/Day 1 up to and 
including the day of the last dose of study drug:

Vitamin E

Hematologic stimulating agents (e.g. erythropoiesis-stimulating agents (ESAs); granulocyte 
colony stimulating factor (GCSF); thrombopoietin (TPO) mimetics)

Investigational agents or devices for any indication

Concomitant use of certain medications or herbal/natural supplements (potent inhibitors of 
OATP or potent or moderate inducers of OATP, CYP2C8, P-gp, or CYP3A) with study 
drug(s) may result in PK interactions resulting in increases or decreases in exposure of study 
drug(s) or concomitant medications. Examples of representative medications which are 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 39
09 February 2017
prohibited from 28 days prior to Baseline/Day 1 through the treatment period are listed below 
in Table 5-1
Table 5-1.
List of Medications Prohibited and to be used with Caution
Drug Class
Agents Disallowed
Use with Caution
Antibiotics
Clarithromycin, Erythromycin
Acid Reducing Agents
H2-Receptor Antagonists a
Antacidsb
Anticonvulsantsc
Carbamazepine, Oxcarbazepine, Phenobarbital, 
Phenytoin
Antimycobacterialsc
Rifabutin, Rifapentine, Rifampin
Endothelin Receptor 
Antagonists
Bosentan
Herbal/Natural 
Supplementsc
St. John’s Wort, Echinaccea. Milk thistle (ie,
silymarin), Chinese herb sho-saiko-to (or Xiao-
Shai-Hu-Tang)
Bile Acid Sequestrantsd
Cholestyramine, Colesevelam, 
Colestipol
Otherc
Modafinil
a
H2-Receptor Antagonists can be taken up to 3 days prior to study drug dosing 
b
Antacids that directly neutralize stomach pH (i.e. Tums, Maalox) are permitted but may not be taken within 4 hours (before 
or after) study drug administration
c
May result in a decrease in the concentrations of study drugs
d      Bile acid sequestrants are permitted but must not be taken within 4 hours (before or after) of study drug administration
Medications for disease conditions excluded from the protocol (eg, HIV-1, HBV, or HCV 
infection, active cancer, transplantation) are not listed under this prohibited medication section 
and are disallowed in the study.
5.6.
Accountability for GS-9674/ PTM GS-9674 
The investigator or designee (eg, pharmacist) is responsible for ensuring adequate accountability 
of all used and unused study drug bottles. This includes acknowledgement of receipt of each 
shipment of study drug (quantity and condition), subject dispensing records, and returned or 
destroyed study product. All used and unused study drug bottles 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 bottles

Record the date, subject number, subject initials, and the study drug bottle number dispensed

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 40
09 February 2017

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
Refer to Section 9.1.7 for instructions regarding study drug return or disposal.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 41
09 February 2017
6.
STUDY PROCEDURES
The study procedures to be conducted for each subject randomized in the study are presented in 
tabular form in Appendix 2 and described in the text that follows. Additional information is 
provided in Study Reference Binder.
The investigator must document any deviation from protocol procedures and notify the sponsor 
or contract research organization (CRO).
6.1.
Subject Randomization and Treatment Assignment
It is the responsibility of the investigator to ensure that subjects are eligible to participate in the 
study prior to randomization and throughout the study. 
Documentation of the personally signed and dated informed consent of each subject, using the 
study-specific ICF, is required before initiating the screening process.
After written informed consent has been obtained and eligibility to participate established, 
investigative site personnel will obtain the subject’s identification number and study drug 
assignment from the interactive web response system (IWRS).
6.2.
Pretreatment Assessments-Screening Visit
Subjects will be screened within 4 weeks before randomization to determine eligibility for 
participation in the study. The screening period may be extended under special circumstances 
with the explicit approval of the Medical Monitor. 
Subjects who fail to meet eligibility criteria may be rescreened. Retesting of subject’s screening 
labs may be permitted if there are reasons to believe that the retest values will be within protocol 
specified parameters.  Reasons may include but will not be limited to sample processing errors 
during initial sampling and extenuating circumstances such as inter-current infections, lab 
mishandling and results abnormal from historic.
Screening labs may be repeated once within the screening period, prior to administration of study 
drug to rule out laboratory error, if any. This will be done at the discretion of the investigator.
The following will be performed and documented at Screening:

Obtain written informed consent before initiation of any screening procedures

Review and record whether the subject meets inclusion and exclusion criteria

Obtain screening number from IWRS

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 42
09 February 2017

Obtain medical history 

Calculate partial Mayo Score for subjects with IBD

Complete physical examination 

Record vital signs (heart rate, systolic and diastolic blood pressure, respiratory rate, and body 
temperature), body weight and height

Obtain blood samples for
Chemistry
Hematology 
Coagulation Panel
Biomarkers
HIV-1/2, HBV and HCV Serology
Serum pregnancy test (female subjects of child bearing potential only)
Serum FSH (only for some female subjects - see Appendix 4) 

Cirrhosis assessment: FibroSURE/FibroTest® and review of historical liver biopsy or 
FibroScan® if available.

Urine drug screen for amphetamines, cocaine and opiates (ie, heroin, morphine)

Record any SAEs and all AEs related to protocol mandated procedures occurring after 
signing of the consent form.

Record all concomitant medications (CMs) that the subject has taken within 28 days prior to 
screening
Subjects meeting all of the inclusion criteria and none of the exclusion criteria will return to the 
clinic within 4 weeks after screening for randomization into the study.
From the time of obtaining informed consent through the first administration of investigational 
medicinal product, record all serious adverse events (SAEs), as well as any AEs related to 
protocol-mandated procedures on the adverse events case report form (eCRF).  All other 
untoward medical occurrences observed during the screening period, including exacerbation or 
changes in medical history are to be captured on the medical history eCRF.  See Section 7
Adverse Events and Toxicity Management for additional details.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Final 
Amendment 3 
6.3. 
Blinded Study Phase: Baseline/Day 1 Randomization and Assessments 
Subjects returning to the clinic for randomization at Baseline/Day 1 will be instructed to fast (no 
food or drink, except water), starting from midnight or earlier, as appropriate, on the evening 
prior to the Baseline/Day 1 visit to ensure an approximate 8-hour fast prior to the blood sample 
collection under fasting condition the next morning. 
After review of inclusion and exclusion criteria to confirm continued eligibility, subjects will be 
randomized to study drug assignment and receive their Subject Identification Number via the 
IWRS prior to their first dose of study drug. Randomization will be stratified by the presence or 
absence of UDCA use. 
The following will be performed and documented at the Baseline/Day 1 visit prior to dosing: 
• 
QoL Questionnaires (PBC-40, SF-36 and PSC PRO) 
• 
Pruritus assessments (Pruritus VAS and 5D-Itch) 
Note: It is recommended that QoL questionnaires be completed prior to any study procedures 
being performed and prior to the subject seeing a health care provider. Refer to the Study 
Reference Binder for guidance on QoL questionnaire administration. 
• 
Calculate partial Mayo Score for subjects with IBD 
• 
Symptom-driven physical examination 
• 
Record vital signs, weight and height 
• 
Obtain Blood samples for: 
Chemistry 
Hematology 
Coagulation Panel 
Lipid Profile 
C-peptide, insulin, and hemoglobin Ale (HbAlc) 
Biomarkers 
Single PD Sampling 
CONFIDENTIAL 
Page 43 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 44
09 February 2017

Conduct standard 12-Lead ECG

Perform FibroScan® (if available)

Perform MRE (if available)

Perform MRCP

Collect urine samples for:
— Urine pregnancy test for females of child bearing potential only 
— Biomarkers

Collect stool sample 

Dispense study drug, and provide subject with instruction on appropriate dosing and 
administration

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the Screening visit
Once all visit procedures have been completed, subjects will take their Baseline/Day 1 dose of 
study drug with food while at the investigative site
Subjects will return to the investigative site at Week 1 (±3 days). 
6.4.
Treatment Assessments (Blinded Study Phase)
6.4.1.
Weeks 1, 2, 4 and 8 (± 3 days)
Subjects will be instructed to fast (no food or drink, except water), starting from midnight 
(00:00) or earlier, as appropriate, on the evening prior to ensure an approximate 8-hour fast prior 
to the fasted blood sample collection the next morning.
Subjects should also be instructed to HOLD their dose of study drug on the day of their visit until 
all visit procedures have been completed. The study drug dose should be taken with food after 
the visit.
The following treatment procedures/assessments are to be completed at the end of Weeks 1, 2, 4, 
and 8 for all subjects (see Appendix 2).

Pruritus assessments (Pruritus VAS and 5D-Itch)

Calculate partial Mayo Score for subjects with IBD

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
• 
Symptom-driven physical examination 
• 
Record vital signs and body weight 
• 
Obtain blood samples for: 
Chemistry 
Hematology 
Coagulation Panel 
Lipid Profile at Weeks 1, 4 and 8 
Biomarkers at Weeks 1 and 4 
Single PK and PD sampling 
• 
Obtain urine samples for: 
Final 
Amendment 3 
Urine pregnancy testing (female of childbearing potential only) at Weeks 1, 4 and 8 
Biomarkers at Weeks 1 and 4 
• 
Dispense the study drug as directed by IWRS (if applicable) 
-
Review study drug compliance and drug administration instructions with subject 
-
Reconcile study drug administration using pill counts at Weeks 4 and 8 
• 
Record all CMs that the subject has taken since the previous visit 
• 
Record any SAEs and all AEs occurring since the previous visit 
6.4.2. 
Week 12 (± 3 days) 
Subjects will be instructed to fast (no food or drink, except water), starting from midnight 
(00:00) or earlier, as appropriate, on the evening prior to the Week 12 visits to ensure an 
approximate 8-hour fast prior to the fasted blood sample collection the next morning. 
The following treatment procedures/assessments are to be completed at this visit. 
CONFIDENTIAL 
Page 45 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 46
09 February 2017

QoL Questionnaires (PBC-40, SF-36 and PSC PRO)

Pruritus assessments (Pruritus VAS and 5D-Itch)

Calculate partial Mayo Score for subjects with IBD

Symptom-driven physical examination

Record vital signs and body weight

Obtain blood samples for:
Chemistry
Hematology
Coagulation Panel
Lipid Profile
C-peptide, insulin and hemoglobin A1c
Biomarkers
Single PK and PD sampling

Obtain urine samples for:
— Urine pregnancy testing (female of childbearing potential only)
— Biomarker assessments

Collect stool sample 

Conduct standard 12-Lead ECG

Perform FibroScan® (if available) 

Review study drug compliance
— Reconcile study drug administration using pill counts
— All study drugs should be returned at this visit

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the previous visit

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 47
09 February 2017
Once all visit procedures have been completed, subjects will self-administer their last dose of 
study drug while at the investigative site. 
If a subject discontinues treatment early for any reason, they should complete the 12 week 
treatment visit assessment/ Early Termination Visit (ET) assessments and then the follow-up
visit (4 weeks following the last dose of the study drug) should be completed (see Appendix 2).
6.5.
Blinded Study Phase follow-up Visit (±5 days)
Subjects will return for a Blinded Study Phase follow-up visit after completing their 12 weeks of 
treatment. The ET subjects should also complete the follow-up visit after completing the ET 
visit. 
Subjects should be instructed to fast (no food or drink, except water), starting from midnight 
(00:00) or earlier, as appropriate, on the evening prior to their visits to ensure an approximate 
8-hour fast prior to the fasted blood sample collection the next morning.
The Blinded Study Phase follow-up visit will be completed 4 week post last dose of study drug.
The following will be performed and documented at this visit (see Appendix 2).

QoL Questionnaires (PBC-40, SF-36 and PSC PRO) 

Pruritus assessments (Pruritus VAS and 5D-Itch)

Calculate partial Mayo Score for subjects with IBD

Symptom-driven physical examination

Record vital signs and body weight

Obtain blood samples for:
— Chemistry
— Hematology
— Coagulation Panel
— Lipid Profile
— Biomarkers

Obtain urine samples for:
— Urine pregnancy testing (females of childbearing potential only)
— Biomarkers

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the previous visit

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 48
09 February 2017
Subjects will be unblinded to their Blinded Study Phase treatment assignment after the primary 
analysis has been completed, approximately 6 weeks after all subjects have completed the 
Blinded Study Phase or early terminated.
Subjects must have their OLE Baseline/Day 1 visit within 30 days of completing the Blinded 
Study Phase follow-up. 
If OLE Baseline/Day 1 and Blinded Study Phase follow-up visit is on the same day subjects 
should only complete OLE Baseline /Day 1 assessments.
6.6.
Open Label Extension (OLE) Phase (± 3 days for Weeks 1–12 and ± 5 days
for Weeks 24-96)
Subjects will be instructed to fast (no food or drink, except water), starting from midnight 
(00:00) or earlier, as appropriate, on the evening prior to their visits to ensure an approximate 8-
hour fast prior to the fasted blood sample collection the next morning.
Subjects should also be instructed to HOLD their dose of study drug on the day of the 
Baseline/Day 1 visit until all visit procedures have been completed. The study drug dose should 
be taken with food after the visit.
The following treatment procedures/assessments are to be completed at the OLE Baseline/Day 1
Visit, followed by OLE Weeks 1, 2, 4, 8, 12, 24, 36, 48, 60, 72, 84 and 96 weeks (see 
Appendix 2).

QoL Questionnaires (PBC-40, SF-36 and PSC PRO) at OLE Baseline/Day 1, Weeks 4, 12 
and every 12 weeks thereafter 

Pruritus assessments (Pruritus VAS and 5D-Itch)

Calculate partial Mayo Score for subjects with IBD (phone follow-up every 4 weeks after 
OLE Week 12 if no in-clinic appointment scheduled to identify symptoms suggestive of 
worsening IBD)

Symptom-driven physical examination

Record vital signs and body weight

Perform MRE at OLE Weeks 48 and 96 (if available)

Perform MRCP at OLE Weeks 48 and 96

For subjects with history of IBD, any evidence of active IBD seen on routinely performed 
colonoscopy will be captured

Obtain blood samples for

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 49
09 February 2017
Chemistry
Hematology
Coagulation Panel
Lipid Profile
Biomarkers at OLE Baseline/Day 1, Weeks 4, 12 and every 12 weeks thereafter

Obtain urine samples for:
— Urine pregnancy testing (females of childbearing potential only) at OLE Baseline/Day 1, 
and every 4 weeks thereafter 
— Biomarkers at OLE Baseline/Day 1, Weeks 24, 48, 72 and 96 only

Collect stool sample at OLE Baseline/Day 1, Week 48 and Week 96 only

Dispense the study drug as directed by IWRS at OLE Baseline/Day 1, Weeks 4, 8, 12 and 
every 12 weeks thereafter 
Review study drug compliance and drug administration instructions with subject
— Reconcile study drug administration using pill counts
— Study drug should be returned at Week 96 visit

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the previous visit
6.7.
Unscheduled Visits
Additional unscheduled assessments may be performed at the discretion of the investigator.
Subjects returning to the clinic for an unscheduled visit will be instructed to fast (no food or 
drink, except water), starting from midnight (00:00) or earlier, as appropriate, on the evening 
prior to the visit to ensure an approximate 8-hour fast prior to the blood sample collection under 
fasting condition the next morning.
Subjects should also be instructed to HOLD their dose of study drug on the day of an 
unscheduled visit until all visit procedures have been completed. The study drug dose should be 
taken with food after the visit.
At a minimum, the following will be performed and documented.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 50
09 February 2017

Calculate partial Mayo Score for subjects with IBD

Symptom-driven physical examination

Obtain blood samples for:
— Chemistry
— Hematology
— Single PK and PD should be collected for any unscheduled visit during Blinded Study 
Phase (Weeks 1 to 12 visits).

Record body weight

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the previous visit
6.8.
OLE follow-up Visit (±5 days)
Subjects will return for OLE follow-up visit after completing their OLE Week 96 visit. Subjects 
should also complete the follow-up visit after completing the ET visit for the OLE Phase. 
The OLE follow-up visit will be completed 4 week post last dose of study drug.
The following will be performed and documented at this visit (see Appendix 2).

Pruritus assessments (Pruritus VAS and 5D-Itch)

Calculate partial Mayo Score for subjects with IBD

Symptom-driven physical examination

Record vital signs and body weight

Obtain blood samples for:
— Chemistry
— Hematology
— Coagulation Panel
— Lipid Profile

Urine pregnancy test for female subjects of child bearing potential only 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 51
09 February 2017

Record all CMs that the subject has taken since the previous visit

Record any SAEs and all AEs occurring since the previous visit
6.9.
Assessments for Premature Discontinuation from Study
Subjects prematurely discontinuing from the study either during the Blinded Study Phase or 
during the OLE Phase (for example, as a result of an AE), should have an Early Termination 
(ET) visit completed followed by a follow-up visit 4 weeks after the last dose of the study 
medication. The study assessments to be performed at the ET visit are the same as those 
performed at the Week 12 visit (refer to Section 6.4.2) for ET subjects in the Blinded Study 
Phase and Week 96 visit for ET subjects in the OLE Phase (refer to Section 6.6). The study 
assessments to be performed at the follow-up visits are listed in Section 6.5 and 6.8 respectively. 
The subject will then be withdrawn from the study.
If these visits are not possible or acceptable to the subject or investigator, the subject may be 
withdrawn from the study. 
6.10.
Criteria for Discontinuation of Study Treatment
Study medication may be discontinued in the following instances:

Intercurrent illness that would, in the judgment of the investigator, affect assessments of 
clinical status to a significant degree. Following resolution of intercurrent illness, the subject 
may resume study dosing at the discretion of the investigator.

Subject noncompliance

Sponsor discretion
Study medication must be discontinued in the following instances:

Unacceptable toxicity,  or toxicity that, in the judgment of the investigator, compromises the 
ability to continue study-specific procedures or is considered to not be in the subject’s best 
interest

Subject request to discontinue for any reason

Pregnancy 

Discontinuation of the study at the request of Gilead, a regulatory agency or an institutional 
review board or independent ethics committee (IRB/IEC)

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
6.11. 
PK and PD Substudy Visits 
PPD 
6.12. 
Procedures and Specifications 
6.12.1. 
Clinical Laboratory Analytes 
Chemistry: 
Final 
Amendment 3 
Alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, alkaline 
phosphatase (ALP), bicarbonate, blood urea nitrogen (BUN), calcium, chloride, creatinine, 
glucose, lactate dehydrogenase (LDH), magnesium, phosphorus, potassium, sodium, total and 
direct bilirubin, total protein, uric acid, gamma-glutamyl transferase (GGT). Also includes 
C-Peptide, insulin and hemoglobin Ale (HbAlc) for the Baseline/Day! and Week 12 visits. 
Hematology: 
Hematocrit (Hct), hemoglobin (Hb ), platelet count, red blood cell count (RBC), white blood cell 
count (WBC) with differential (absolute and percentage) including lymphocytes, monocytes, 
neutrophils, eosinophils, and basophils and, reticulocyte count and mean corpuscular volume 
(MCV). 
Coagulation Panel: 
Prothrombin time (PT), partial thromboplastin time (PTT), and international normalized ratio 
(INR) 
Pregnancy Tests: 
Serum ~-hCG or urine ~-hCG (if positive, requires immediate confirmation with Serum ~-hCG) 
Additional Tests: 
Lipid Profile, creatine phosphokinase (CPK), HIV-1, HBV & HCV serology, urine drug screen 
(for amphetamines, cocaine, opiates), and genomic sample collection 
CONFIDENTIAL 
Page 52 
09 February 2017 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Biomarker tests 
Including, but not limited, to biomarkers of: 
Circulating lipids - ApoB and NMR lipoprofile 
Inflammation- hsCRP, TNF-a 
Bone formation -bone specific ALP and PTH 
Liver fibrosis- ELF Test and FibroSURE/FibroTest® 
FXR pathway activity- FGF19, C4 and bile acids 
U1ine samples: 
Final 
Amendment 3 
Collected and stored for future biomarker testing (protein, albumin, retinol binding protein, 
~2-microglobulin and creatinine) 
Pharmacokinetic (PK) and Pharmacodynamic (PD) Assessments 
Single PK and PD Sampling 
Single PK and PD plasma samples will be collected and archived for 1) PK analysis of GS-9674, 
GS-716070 (metabolite of GS-9674 ), and other metabolites as applicable, 2) to measure the 
concentration ofthe PD biomarkers FGF19 and C4. 
6.12.2. 
Medical History 
Medical history including details regarding illnesses and allergies, date(s) of onset, and whether 
condition(s) is currently ongoing, and medication history, including nicotine and alcohol use, 
will be collected on all subjects during screening. 
6.12.3. 
Physical Examination 
A complete physical examination should include source documentation of general appearance, 
and the following body systems: head, neck, and thyroid; eyes, ears, nose, throat, mouth, and 
tongue; chest (excluding breasts); respiratory; cardiovascular; lymph nodes; abdomen; skin, hair, 
nails; musculoskeletal and neurological. 
The focus of a symptom-driven physical examination will be determined by the investigator 
based on subject complaint. For example if a subject complains of a cough a respiratory exam 
CONFIDENTIAL 
Page 53 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 54
09 February 2017
should be performed. If consistent with pneumonia (e.g. rales or crackles are identified) then an 
AE would be documented.
Height and body weight will be collected at specified time points.
6.12.4.
Quality of Life (QoL) Measures and Pruritus Assessments
It is recommended that these questionnaires be completed prior to the clinical and laboratory 
assessments. The subject should read the questionnaires by himself/herself and record the 
answers by himself/herself.
6.12.4.1.
Short Form-36 (SF-36) Health Survey
The SF-36 Health Survey asks 36 questions to measure functional health and well-being from the 
subject’s point of view and consists of eight health domains (physical functioning, role-physical, 
bodily pain, general health, vitality, social functioning, role-emotional, and mental health). These 
health domain scales contribute to the physical health and mental health summary measures. 
6.12.4.2.
Partial Mayo Score
The partial Mayo score is a survey for the assessment of IBD that considers stool frequency and 
rectal bleeding. Subjects with history of IBD will receive a diary with instructions to document 
stool frequency and rectal bleeding. Subjects should be instructed to update this diary on a daily 
basis and should bring this diary back to the site at each visit for partial Mayo Score calculation. 
Any subject who develops a ≥2 point increase in partial Mayo Score should be instructed to 
contact the site to report the change.
6.12.4.3.
PSC Patient-Reported Outcome (PRO) Measure
The PSC PRO addresses the severity of common, everyday symptoms of PSC (e.g. pruritus, 
fatigue, right upper quadrant abdominal discomfort) and their functional impact (e.g. on physical 
function, activities of daily living, work productivity, etc.). 
6.12.4.4.
Primary Biliary Cirrhosis-40 (PBC-40) Questionnaire
The PBC-40 is a health-related QoL questionnaire that includes 40 questions regarding PBC-
related symptoms including itch, fatigue, cognition, and social and emotional assessments
symptoms that are also relevant to the PSC population.  
6.12.4.5.
Pruritus Visual Analog Scale (VAS) measure
The Pruritus VAS is a tool that uses a numeric scale for measuring the intensity of pruritus.
6.12.4.6.
5D-Itch Questionnaire
The 5D- Itch questionnaire is a validated survey for the assessment of the severity of pruritus in 
patients with chronic pruritus due to dermatological and non-dermatological disorders. 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 55
09 February 2017
6.12.5.
Electrocardiogram
Standard 12-lead electrocardiogram (ECG) assessments will be performed. The Investigator will 
review the ECGs for any clinically significant abnormalities to ensure subject safety. Abnormal 
ECG findings that are considered clinically significant by the Investigator and meet the 
definition of an AE should be reported and recorded in the AE eCRF page.
6.12.6.
FibroScan® 
Liver stiffness will be assessed by FibroScan®. It is required that each subject’s FibroScan®
assessments be done with the same type of probe at each study visit. If FibroScan® is not 
available at a site the test may be omitted.
Please refer to the Study Reference Binder for instructions on FibroScan® measurements.
6.12.7.
Magnetic Resonance Elastography
Liver stiffness will be assessed by MRE. It is recommended that each subject’s MRE assessment 
is performed using the same procedure for each study visit.  If MRE is not available at the site, 
the procedure may be omitted.
Please refer 
6.12.8.
Magnetic Resonance Cholangiopancreatography
Imaging of the biliary and pancreatic ducts will be performed by MRCP.  The MRCP images 
will be sent to a central imaging center.  It is recommended that each subject’s MRCP 
assessment is performed using the same procedure for each study visit.  
6.13.
End of Study
End of study is defined as when the last patient last visit (LPLV) for the OLE follow-up visit 
occurs 4 weeks after completing OLE treatment or the OLE ET follow-up visit, whichever 
occurs later.
6.13.1.
Sample Storage
Residual biological samples from all visits will be frozen and stored. These stored samples may 
be used by Gilead or our research partners to help answer questions about the study drug, PSC 
and its associated conditions, or clinical laboratory testing to provide additional safety data. No 
human genetic testing will be performed without express consent of the study subjects. At the 
conclusion of this study, these samples may be retained in storage for Gilead for a period of up to 
15 years.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 56
09 February 2017
7.
ADVERSE EVENTS AND TOXICITY MANAGEMENT
7.1.
Definitions of Adverse Events, Adverse Reactions, and Serious Adverse 
Events
7.1.1.
Adverse Events
An adverse event (AE) is any untoward medical occurrence in a clinical study subject 
administered a medicinal product, which does not necessarily have a causal relationship with the
treatment. An AE can therefore be any unfavorable and/or unintended sign, symptom, or disease 
temporally associated with the use of a medicinal product, whether or not considered related to 
the medicinal product. AEs may also include pre- or post-treatment complications that occur as a 
result of protocol specified procedures, 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 7.6.1)

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 
CRF.
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

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 57
09 February 2017

Persistent or significant disability/incapacity

A congenital anomaly/birth defect

A medically important event or reaction: such events may not be immediately 
life-threatening or result in death or hospitalization but may jeopardize the subject or may 
require intervention to prevent one of the other outcomes constituting SAEs. Medical and 
scientific judgment must be exercised to determine whether such an event is a reportable 
under expedited reporting rules. Examples of medically important events include intensive 
treatment in an emergency room or at home for allergic bronchospasm; blood dyscrasias or 
convulsions that do not result in hospitalization; and development of drug dependency or 
drug abuse. For the avoidance of doubt, infections resulting from contaminated medicinal 
product will be considered a medically important event and subject to expedited reporting 
requirements.
7.1.3.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events
Laboratory abnormalities without clinical significance are not recorded as AEs or SAEs. 
However, laboratory abnormalities (eg, clinical chemistry, hematology, and urinalysis) that 
require medical or surgical intervention or lead to study drug interruption, modification, or 
discontinuation must be recorded as an AE, as well as an SAE, if applicable. In addition, 
laboratory or other abnormal assessments (eg, electrocardiogram, x-rays, vital signs) that are 
associated with signs and/or symptoms must be recorded as an AE or SAE if they meet the 
definition of an AE or SAE as described in Sections 7.1.1 and 7.1.2. If the laboratory 
abnormality is part of a syndrome, record the syndrome or diagnosis (eg, anemia), not the 
laboratory result (ie, decreased hemoglobin).
For specific information on handling of clinical laboratory abnormalities in this study, please 
refer to (Section 7.5).
7.2.
Assessment of Adverse Events and Serious Adverse Events
The investigator or qualified subinvestigator is responsible for assessing AEs and SAEs for 
causality and severity, and for final review and confirmation of accuracy of event information 
and assessments.
7.2.1.
Assessment of Causality for Study Drugs and Procedures
The investigator or qualified subinvestigator is responsible for assessing the relationship to 
GS-9674 therapy using clinical judgment and the following considerations:

No: Evidence exists that the adverse event has an etiology other than the GS-9674. For 
SAEs, an alternative causality must be provided (eg, pre-existing condition, underlying 
disease, intercurrent illness, or concomitant medication).

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 58
09 February 2017

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. 
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 grading of AEs will be assessed as Grade 1, 2, 3, 4 or 5 according 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
(Appendix 3).
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 distinction between the seriousness and the severity of an adverse event should be noted. 
Severe is a measure of intensity; thus, a severe reaction is not necessarily a serious reaction. For 
example, a headache may be severe in intensity, but would not be classified as serious unless it 
met one of the criteria for serious events listed above.
7.3.
Investigator Requirements and Instructions for Reporting Adverse Events 
and Serious Adverse Events to Gilead
Requirements for collection prior to study drug initiation:
After informed consent, but prior to initiation of study medication, the following types of events 
should be reported on the case report form (eCRF): all SAEs and adverse events related to 
protocol-mandated procedures.
Adverse Events
Following initiation of study medication, collect all AEs, regardless of cause or relationship, 
until 30 days after last administration of GS-9674; AEs must be reported to the eCRF database as 
instructed.
All AEs should be followed up until resolution or until the adverse event is stable, if possible. 
Gilead Sciences may request that certain AEs be followed beyond the protocol defined follow up 
period.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 59
09 February 2017
Serious Adverse Events
All SAEs, regardless of cause or relationship, that occurs after the subject first consents to 
participate in the study (ie, signing the informed consent) and throughout the duration of the 
study, including the protocol-required post treatment follow-up period, must be reported to the 
eCRF database and Gilead Drug Safety and Public Health (DSPH) as instructed. This also 
includes any SAEs resulting from protocol-associated procedures performed after informed 
consent is signed.
Any SAEs and deaths that occur after the post treatment follow-up visit and within 30 days of 
the last dose of study drug, 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 Gilead DSPH.

All AEs and SAEs will be recorded in the eCRF database within the timelines outlined in the 
eCRF completion guideline. 
Electronic Serious Adverse Event (eSAE) Reporting Process

Site personnel record all SAE data in the eCRF database and from there transmit the SAE 
information to Gilead DSPH 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 to:
Gilead DSPH
Email:
Safety_FC@gilead.com
Fax:
+1 650-522-5477

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.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 60
09 February 2017

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.
Gilead Reporting Requirements
Depending on relevant local legislation or regulations, including the applicable US FDA Code of 
Federal Regulations, the EU Clinical Trials Directive (2001/20/EC) and relevant updates, and 
other country-specific legislation or regulations, Gilead may be required to expedite to 
worldwide regulatory agencies reports of SAEs, serious adverse drug reactions (SADRs), or 
suspected unexpected serious adverse reactions (SUSARs). In accordance with the EU Clinical 
Trials Directive (2001/20/EC), Gilead or a specified designee will notify worldwide regulatory 
agencies and the relevant IEC in concerned Member States of applicable SUSARs as outlined in 
current regulations.
Assessment of expectedness for SAEs will be determined by Gilead using reference safety 
information specified in the investigator’s brochure or relevant local label as applicable. 
All investigators will receive a safety letter notifying them of relevant SUSAR reports associated 
with any study drug. The investigator should notify the IRB 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.
To minimize the possibility of exposing study subjects to unusual risk, the safety information 
from this study will also be reviewed periodically by an independent Data Monitoring 
Committee (DMC). The DMC may have access to partially blinded or unblinded data and will 
make recommendations regarding the study according to the DMC charter. See Section 8.12 for
additional details regarding the DMC.
7.5.
Toxicity Management 
7.5.1.
PSC Specific Study Stopping Rule:
Any subject without a history of IBD, who develops new onset IBD while participating in the 
study, must be discontinued from the study. Any subject with a history of IBD who experiences 
at least a 2-point increase in the partial Mayo score while in the study must be discontinued from 
the study. Also, any subject who experiences ≥ 2 episodes of ascending cholangitis in a 6-month 
period, clinical evidence of hepatic decompensation (e.g., ascites, variceal hemorrhage, or 
hepatic encephalopathy), and/or the occurrence of cholangiocarcinoma or hepatocellular 
carcinoma must also be discontinued from the study.
7.5.2.
Observation for Drug Induced Liver Injury (DILI):
Although subjects randomized in this study will have baseline liver disease, their hepatic 
function should not be significantly impaired. However, at baseline, some may have liver 
biochemistry levels above the upper limit of normal (ULN). Baseline values for liver tests (ALT, 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 61
09 February 2017
AST, and total bilirubin) will be determined by averaging the values obtained at screening and 
Baseline/Day 1.  
For subjects with ALT and/or AST below ULN at study start, close observation for DILI (as 
described below) will be performed in subjects with any of the following criteria (all labs 
confirmed by repeat testing), unless an alternative cause for the combination of laboratory 
abnormalities is apparent in the opinion of the principal investigator:

ALT or AST > 3 x ULN 

Total bilirubin > 2 x ULN

INR >1.5 (except for subjects on anticoagulant therapy)  

Clinical signs or symptoms that are, in the opinion of the investigator, consistent with 
hepatitis (such as right upper quadrant discomfort, fever, nausea, vomiting, jaundice, rash, or 
eosinophilia > 5%)
For subjects with ALT and/or AST between 1 and 10 x ULN at study start, close observation for 
DILI (as described below) will be performed in subjects with any of the following criteria (all 
labs confirmed by repeat testing), unless an alternative cause for the combination of laboratory 
abnormalities is apparent in the opinion of the principal investigator:

ALT or AST > 2 x baseline at any time

Total bilirubin > 2 x ULN  

INR >1.5 (except for subjects on anticoagulant therapy)  

Clinical signs or symptoms that are, in the opinion of the investigator, consistent with 
hepatitis (such as right upper quadrant discomfort, fever, nausea, vomiting, jaundice, rash, or 
eosinophilia > 5%).  
Close observation includes:

Repeating liver biochemistries (ALT, AST, ALP, total bilirubin, INR) and obtaining CPK 
levels within 2 working calendar days upon receipt of the laboratory results.

Obtaining a more detailed history of symptoms and prior or concurrent disease

Obtaining a history of concomitant drug use (including nonprescription medications and 
herbal and dietary supplement preparations), alcohol use, recreational drug use, and special 
diets

Obtaining a history of exposure to environmental chemical agents

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 62
09 February 2017

Ruling out other causes of liver disease as needed (obtain viral hepatitis panel, imaging for 
evaluation of biliary tract disease, etc. if required in the opinion of the primary investigator)

Continue to monitor liver biochemistries twice weekly. Frequency can decrease to once a 
week or less if abnormalities stabilize or study drug has been discontinued and subject is 
asymptomatic
During a period of close observation, study drug can be continued, if desired, at the discretion of 
the Gilead Medical Monitor and the principal investigator during the DILI evaluation. 
However, for all subjects, study drug should be withheld if any of the following criteria are met:

ALT or AST > 5 x baseline

ALT or AST >10 x ULN 

ALT or AST >3 x baseline with 1 or more of the following:
Total bilirubin > 2 x ULN or 1.5 x baseline
INR > 1.5 (except for subjects on anticoagulant therapy)
Appearance of clinical signs or symptoms that are, in the opinion of the investigator, 
consistent with drug-induced hepatotoxicity

ALT or AST > baseline with any 2 or more of the following:
Total bilirubin > 2 x ULN or 1.5 x baseline
INR >1.5 (except for subjects on anticoagulant therapy)
Appearance of clinical signs or symptoms that are, in the opinion of the investigator, 
consistent with drug-induced hepatotoxicity
AND

No other cause for the combination of laboratory abnormalities is immediately apparent (e.g. 
prolonged INR with warfarin use). Important potential causes or contributors to abnormal 
AST/ALT or total bilirubin values include, but are not limited to:
— Obstructive gall bladder or bile duct disease
— Viral or alcoholic hepatitis (e.g. hepatitis A/B/C/D/E, Epstein-Barr virus, 
cytomegalovirus, herpes simplex virus, varicella)
— Autoimmune hepatitis
— Concomitant administration of other hepatotoxins, including excessive doses of 
acetaminophen, drugs that inhibit bilirubin glucuronidation (e.g. indinavir, atazanavir, 
irinotecan), or herbal or dietary supplements

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 63
09 February 2017
— Hypoxic or ischemic hepatopathy or congestive hepatopathy in association with 
significant right-sided heart failure
— Wilson disease
— Nonalcoholic fatty liver disease (NAFLD)
— Progression of malignancy involving the liver (note that metastatic disease to the liver, by 
itself, should not be used as an explanation for significant AST/ALT elevations)
If study drugs are withheld, they may be reintroduced with approval from the Medical Monitor if 
another etiology for elevated liver tests is present. Study drug must be discontinued if close 
monitoring of a patient for DILI is not possible or if total bilirubin, ALT or AST elevation recurs 
following re-challenge with study drug.
Treatment-emergent toxicities will be noted by the Investigator and brought to the attention of 
the Medical Monitor. 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.

Other than in the case of the liver enzymes noted above, Grade 3 or 4 clinically significant 
laboratory AEs should be confirmed by repeat testing as soon as practical to do so, and 
preferably within 3 calendar days of receipt of the original test results.

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.

Any questions regarding toxicity management should be directed to the Medical Monitor.
7.6.
Special Situations Reports
7.6.1.
Definitions of Special Situations
Special situation reports include all reports of medication error, abuse, misuse, overdose, reports 
of AEs associated with product complaints, occupational exposure with an AE, pregnancy 
reports regardless of an associated AE, and AE in an infant following exposure from 
breastfeeding.  
Medication error is any unintentional error in the prescribing, dispensing, or administration of a 
medicinal product while in the control of the health care provider, subject, or consumer. 
Abuse is defined as persistent or sporadic intentional excessive use of a medicinal product by a 
subject.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 64
09 February 2017
Misuse is defined as any intentional and inappropriate use of a medicinal 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 a medicinal 
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).
Product complaint is defined as complaints arising from potential deviations in the manufacture, 
packaging, or distribution of the medicinal product.  
Occupational exposure with an AE: exposure to a medicinal product as a result of one’s 
professional or non-professional occupation.
7.6.2.
Instructions for Reporting Special Situations
7.6.2.1.
Instructions for Reporting Pregnancies
The investigator should report pregnancies in female study subjects that are identified after 
initiation of study medication and throughout the study, including the post study drug follow-up 
period, to Gilead DSPH 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.
A spontaneous abortion is always considered to be an SAE and will be reported as described in 
Sections 7.1.1 and 7.1.2. Furthermore, any SAE occurring as an adverse pregnancy outcome post 
study must be reported to Gilead DSPH.
The subject should receive appropriate monitoring and care until the conclusion of the 
pregnancy. The outcome should be reported to Gilead DSPH using the pregnancy outcome report 
form. If the end of the pregnancy occurs after the study has been completed, the outcome should 
be reported directly to Gilead DSPH. Gilead DSPH contact information is as follows: Email: 
Safety_FC@gilead.com and Fax: +1 (650) 522-5477. 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 65
09 February 2017
Pregnancies of female partners of male study subjects exposed to Gilead or other study drugs 
must also be reported and relevant information should be submitted to Gilead DSPH using the 
pregnancy and pregnancy outcome forms within 24 hours. Monitoring of the subject should 
continue until the conclusion of the pregnancy. If the end of the pregnancy occurs after the study 
has been completed, the outcome should be reported directly to Gilead DSPH, fax number +1 
650 522-5477 or email Safety_FC@gilead.com. 
Refer to Appendix 4 for Pregnancy Precautions, Definition for Female of Childbearing Potential, 
and Contraceptive Requirements.
7.6.2.2.
Reporting Other Special Situations
All other special situation reports must be reported on the special situations report form and 
forwarded to Gilead DSPH within 24 hours of the investigator becoming aware of the situation. 
These reports must consist of situations that involve study drug and/or Gilead concomitant 
medications, but do not apply to non-Gilead concomitant medications. 
Special situations involving non-Gilead concomitant medications does not need to be reported on 
the special situations report form; however, for special situations that result in AEs due to a non-
Gilead concomitant medication, the AE should be reported on the AE form. 
Any inappropriate use of concomitant medications prohibited by this protocol should not be 
reported as “misuse,” but may be more appropriately documented as a protocol deviation.
Refer to Section 7.3 and the eCRF completion guidelines for full instructions on the mechanism 
of special situations reporting.
All clinical sequelae in relation to these special situation reports will be reported as AEs or SAEs 
at the same time using the AE eCRF and/or the SAE report form. Details of the symptoms and 
signs, clinical management, and outcome will be reported, when available.

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
8. 
STATISTICAL CONSIDERATIONS 
Details will be provided in the Statistical Analysis Plan (SAP). 
8.1. 
Analysis Objectives and Endpoints 
8.1.1. 
Analysis Objectives 
The primary objective of this study is: 
• 
To evaluate the safety and tolerability of GS-9674 in subjects with PSC 
The exploratory objectives ofthis study are: 
IT 
I 
I 
I 
I 
I 
I 
I 
I 
I 
8.1.2. 
P1imary Endpoint 
-
Final 
Amendment 3 
The primary endpoint is the safety of GS-9674 in subjects with PSC without cirrhosis. The safety 
and tolerability of GS-9674 will be evaluated by examining the incidence of treatment-emergent 
adverse events, including serious adverse events, clinical laboratory tests, and vital signs 
assessments at various time points during the study. 
CONFIDENTIAL 
Page 66 
09 February 2017 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
8.1.3. 
I 
I -
I 
I -
I 
I 
I 
I 
I 
I 
r 
I 
8.2. 
8.2.1. 
8.2.1.1. 
Exploratory Endpoints 
Analysis Conventions 
Analysis Sets 
Efficacy 
Final 
Amendment 3 
The primary analysis set for efficacy analysis will be the Full Analysis Set (F AS) which includes 
all subjects who were randomized into the study and received at least one dose of study drug. 
Subjects who receive study drug other than that to which they were assigned will be analyzed 
according to the treatment group to which they were randomized. 
CONFIDENTIAL 
Page 67 
09 February 2017 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
8.2.1.2. 
Safety 
Final 
Amendment 3 
The primary analysis set for safety analyses will include all subjects who received at least one 
dose of study drug. Treatment-emergent data will be analyzed and defined as data collected from 
the first dose of study drug through the date of last dose of study drug plus 30 days. Subjects 
who received study drug other than that to which they were assigned will be analyzed according 
to the study drug received. 
8.2.1.3. 
Pharmacokinetics 
There are two pharmacokinetic analysis sets: 1) the PK analysis set which includes 
concentration data from the s · 
drawn at each visit 
The PK analysis set will include all randomized subjects who took at least one dose of study 
drug and for whom concentration data of analytes GS-9674 (and its metabolites as applicable) 
are available. The PK analysis set will be used for analyses of population PK. 
PPD 
8.2.1.4. 
Pharmacodynamics 
There are two pharmacodynamics analysis sets: 1) The PD 
is set which includes 
concentration data from the s · 
drawn at each visit 
The PD analysis set will include all randomized subjects who took at least one dose of study 
drug and for whom concentration data ofFGF19, C4, and bile acids are available. The PD 
analysis set may be used for descriptive and/or population based PD analyses as applicable. 
PD 
8.2.1.5. 
Biomarkers 
The Biomarker Analysis Set will include data from subjects in the Safety Analysis Set who have 
the necessary baseline and on-study measurements to provide interpretable results for the 
specific parameters of interest. 
CONFIDENTIAL 
Page 68 
09 February 2017 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
8.2.2. 
Analysis by Study Phase 
Final 
Amendment 3 
Result of statistical analysis for the randomized phase will be presented by treatment groups. 
Safety data from the OLE Phase will be summarized for overall subjects who roll-over into the 
OLE Phase for safety review, supporting regulatory document update or publication purposes. 
8.3. 
Data Handling Conventions 
Missing data can have an impact on the interpretation of the trial data. In general, values for 
missing data will not be imputed. 
Where appropriate, safety data for subjects that did not complete the study will be included in 
summary statistics. For example, if a subject received study medication, the subject will be 
included in a summary of adverse events according to the treatment received; otherwise, if the 
subject is not dosed then they will be excluded from the summary. If safety laboratory results for 
a subject are missing for any reason at a time point, the subject will be excluded from the 
calculation of summary statistics for that time point. If the subject is missing a pre-dose value, 
then the subject will be excluded from the calculation of summary statistics for the pre-dose 
value and the change from pre-dose values. 
Values for missing safety laboratory data and vital signs will not be imputed; however, a missing 
baseline result will be replaced with a screening result, if available. If no pre-treatment 
laboratory value is available, the baseline value will be assumed to be normal (ie, no grade 
[Grade 0]) for the summary of graded laboratory abnormalities. 
8.4. 
Demographic Data and Baseline Characteristics 
Demographic and baseline measurements will be summarized using standard descriptive 
methods (n, mean, SD, median, Ql, Q3, minimum, and maximum) by treatment group and 
overall. Demographic summaries will include sex, race/ethnicity, and age. 
Baseline characteristics summary will include body weight, height, body mass index, and other 
disease characteristics. 
8.5. 
Efficacy Analysis 
8.6. 
Exploratory Analyses 
PPD 
CONFIDENTIAL 
Page 69 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 70
09 February 2017
8.7.
Safety Analysis
All safety data collected on or after the date that GS-9674 was first dispensed up to the date of 
last dose of GS-9674 plus 30 days will be summarized by treatment group. Data for the 
pretreatment and follow-up periods will be included in data listings.
8.7.1.
Extent of Exposure
Data for a subject’s extent of exposure to GS-9674 will be generated from the study drug 
administration eCRF. Exposure data will be summarized by treatment group. 
8.7.2.
Adverse Events
Clinical and laboratory 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. Adverse event severity will be graded using the CTCAE 
Version 4.03.
Events will be summarized on the basis of the date of onset for the event. Treatment-emergent 
adverse events (TEAEs) are defined as 1 or both of the following:

Any AEs with an onset date on or after the study drug start date and no later than 30 days 
after permanent discontinuation of study drug

Any AEs leading to premature discontinuation of study drug
Summaries (number and percentage of subjects) of TEAEs by SOC and PT will be provided.  
Treatment-emergent AEs will also be summarized by relationship to study drug and severity.  In 
addition, TEAEs leading to premature discontinuation of study drug and study will be 
summarized and listed.
All AEs collected during the course of the study will be presented in data listings with a field for 
treatment-emergent event (yes/no).
8.7.3.
Laboratory Evaluations
Selected laboratory data will be summarized (n, mean, SD, Median, Q1, Q3, minimum, and 
maximum) by treatment group and study visit along with the corresponding change from 
baseline values. 
Graded laboratory abnormalities will be defined using the grading scheme in the CTCAE 
Version 4.03 (Appendix 3). Grading of laboratory abnormalities for analysis purposes will be 
performed by the central laboratory.
Incidence of treatment-emergent laboratory abnormalities, defined as values that increase at least 
1 toxicity grade from baseline at any time post baseline up to and including the date of last dose 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Final 
Amendment 3 
of study drug plus 30 days will be summarized by treatment group. If baseline data are missing, 
then any graded abnormality (ie, at least a Grade 1) will be considered treatment emergent. 
8.7.4. 
Other Safety Evaluations 
Vital sign measurements and 12-lead ECG data will be summarized by treatment group and 
listed by subject. 
8.8. 
Pharmacokinetic Analysis 
Plasma concentrations and pharmacokinetic parameters (eg, AUCtau, Cmax and Ctau) will be 
listed and summarized as appropriate for GS-967 4 (and its metabolites as applicable) using 
descriptive statistics. 
Details ofthe analysis plan will be provided in the pharmacokinetic reporting and analysis plan. 
8.9. 
Pharmacodynamics Analysis 
Primary PD parameters (AUCpartiab Cmax, Cmin as applicable) ofFGF19 and C4 will be listed and 
summarized as appropriate for GS-9674 using descriptive statistics. 
Details ofthe analysis plan will be provided in the pharmacodynamics reporting and analysis 
plan. 
8.10. 
Biomarker Analysis 
Descriptive statistics ofbiomarker expression and change from baseline will be provided at each 
sampling time by treatment. Point estimates and 9 5% confidence intervals may be calculated. 
PPD 
8.11. 
Sample Size 
Due to the exploratory nature of this study, no formal power calculations were used to determine 
sample size. The number of subjects was chosen based on clinical experience with other similar 
proof of concept studies. 
8.12. 
Data Monitoring Committee 
An independent, external data monitoring committee (DMC) that consists of two hepatologists 
and a PhD statistician will review the progress of the study and perform reviews of safety data. 
The DMC will convene once 20 subjects have been randomized and will meet every 3 to 4 
months thereafter to monitor the study for safety events in Blinded Study Phase and every 6 
CONFIDENTIAL 
Page 71 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 72
09 February 2017
months in the OLE Phase. The DMC will meet on an ad hoc basis if there are at least 3 similar 
Grade ≥ 3 serious, treatment-related Common Terminology Criteria for Adverse Events 
(CTCAE) observed in the trial. In the event of two similar treatment-related Grade 4 CTCAE 
events or one treatment-related Grade 5 CTCAE, the DMC will review the data and advise the 
sponsor regarding stopping or continuing the trial. The DMC will provide recommendation to 
Gilead whether the nature, frequency, and severity of adverse effects associated with study 
treatment warrant the early termination of the study in the best interests of the participants, 
whether the study should continue as planned, or the study should continue with modifications. 
The DMC may also provide recommendations as needed regarding study design.
The DMC’s specific activities will be defined by a mutually agreed charter, which will define the 
DMC’s membership, conduct and meeting schedule.
While the DMC will be asked to advise Gilead regarding future conduct of the study, including 
possible early study termination, Gilead retains final decision-making authority on all aspects of 
the study.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 73
09 February 2017
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 Conference on 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 European Union 
Clinical Trials Directive 2001/20/EC and Good Clinical Practice Directive 2005/28/EC.
The investigator will ensure adherence to the basic principles of Good Clinical Practice, as 
outlined in 21 CFR 312, subpart D, “Responsibilities of Sponsors and Investigators,” 21 CFR, 
part 50, 1998, and 21 CFR, part 56, 1998.
The investigator and all applicable subinvestigators will comply with 21 CFR, Part 54, 1998, 
providing documentation of their financial interest or arrangements with Gilead, or proprietary 
interests in the investigational drug under study. This documentation must be provided prior to 
the investigator’s (and any subinvestigator’s) participation in the study. The investigator and 
subinvestigator agree to notify Gilead of any change in reportable interests during the study and 
for 1 year following completion of the study. Study completion is defined as the date when the 
last subject completes the protocol-defined activities.
9.1.2.
Institutional Review Board (IRB)/Independent Ethics Committee (IEC) 
Review and Approval
The investigator (or sponsor as appropriate according to local regulations) will submit this 
protocol, informed consent form, and any accompanying material to be provided to the subject 
(such as advertisements, subject information sheets, or descriptions of the study used to obtain 
informed consent) to an IRB/IEC/EC. The investigator will not begin any study subject activities 
until approval from the IRB/IEC/EC 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/EC any modifications made to the protocol or any accompanying material to be 
provided to the subject after initial IRB/IEC/EC approval, with the exception of those necessary 
to reduce immediate risk to study subjects.
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/EC -approved consent form for documenting 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 74
09 February 2017
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/EC
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/EC, 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. NOTE: The investigator must keep a screening log showing 
codes, names, and addresses for all subjects screened and for all subjects randomized in the trial.
Subject data will be processed in accordance with all applicable regulations. 
The investigator agrees that all information received from Gilead, including but not limited to the 
investigator brochure, this protocol, eCRF, the study drug, and any other study information, 
remain the sole and exclusive property of Gilead during the conduct of the study and thereafter. 
This information is not to be disclosed to any third party (except employees or agents directly 
involved in the conduct of the study or as required by law) without prior written consent from 
Gilead. The investigator further agrees to take all reasonable precautions to prevent the 
disclosure by any employee or agent of the study site to any third party or otherwise into the 
public domain.
9.1.5.
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, CRF and query forms
IRB/IEC and governmental approval with correspondence, informed consent, drug records, staff 
curriculum vitae and authorization forms, and other appropriate documents and correspondence.
The required source data should include sequential notes containing at least the following 
information for each subject:

Subject identification (name, date of birth, gender);

Documentation that subject meets eligibility criteria, ie, history, physical examination, and 
confirmation of diagnosis (to support inclusion and exclusion criteria);

Documentation of the reason(s) a consented subject is not randomized;

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 75
09 February 2017

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 study drug, including dates of dispensing and 
return;

Record of all adverse events and other safety parameters (start and end date, and including 
causality and severity);

Concomitant medication (including start and end date, dose if relevant; dose changes);

Date of study completion and reason for early discontinuation, if it occurs.
All clinical study documents must be retained by the investigator until at least 2 years or 
according to local laws, whichever is longer, after the last approval of a marketing application in 
an ICH region (ie, United States, Europe, or Japan) and until there are no pending or planned 
marketing applications in an ICH region; or, if no application is filed or if the application is not 
approved for such indication, until 2 years after the investigation is discontinued and regulatory 
authorities have been notified. Investigators may be required to retain documents longer if 
specified by regulatory requirements, by local regulations, or by an agreement with Gilead. The 
investigator must notify Gilead before destroying any clinical study records.
Should the investigator wish to assign the study records to another party or move them to another 
location, Gilead must be notified in advance.
If the investigator cannot provide for this archiving requirement at the study site for any or all of 
the documents, special arrangements must be made between the investigator and Gilead to store 
these records securely away from the site so that they can be returned sealed to the investigator 
in case of an inspection. When source documents are required for the continued care of the 
subject, appropriate copies should be made for storage away from the site.
9.1.6.
Case Report Forms
For each subject consented, an electronic case report form (eCRF) will be completed by an 
authorized study staff member whose training for this function is documented according to study 
procedures. eCRF should be completed on the day of the subject visit to enable the sponsor to 
perform central monitoring of safety data.  The Eligibility Criteria eCRF should be completed 
only after all data related to eligibility have been received.  Subsequent to data entry, a study 
monitor will perform source data verification within the EDC system. Original entries as well as 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 76
09 February 2017
any changes to data fields will be stored in the audit trail of the system.  Prior to database lock 
(or any interim time points as described in the clinical data management plan), the investigator 
will use his/her log in credentials to confirm that the forms have been reviewed, and that the 
entries accurately reflect the information in the source documents. The eCRF capture the data 
required per the protocol schedule of events and procedures. System-generated or manual 
queries will be issued to the investigative site staff as data discrepancies are identified by the 
monitor or internal Gilead staff, who routinely review the data for completeness, correctness, and 
consistency. The site coordinator is responsible for responding to the queries in a timely manner, 
within the system, either by confirming the data as correct or updating the original entry, and 
providing the reason for the update (e.g. data entry error). At the conclusion of the trial, Gilead 
will provide the site with a read-only archive copy of the data entered by that site. This archive 
must be stored in accordance with the records retention requirements outlined in Section 9.1.5.
9.1.7.
Investigational Medicinal Product Accountability and Return
Where possible, study drug should be destroyed at the site. If the site does not have acceptable 
procedures in place for drug destruction, arrangements will be made between the site and 
Gilead Sciences (or Gilead Sciences’ representative) for return of unused study drug supplies. 
The study monitor will provide instructions for return.
The study monitor will evaluate each study center’s study drug disposal procedures and provide 
appropriate instruction for destruction of unused study drug supplies. If the site has an 
appropriate standard operating procedure (SOP) for drug destruction as determined by Gilead 
QA, the site may destroy used (empty or partially empty) and unused study drug supplies in 
accordance with that site’s approved SOP. A copy of the site’s approved SOP will be obtained 
for central files. 
If study drug is destroyed on site, the investigator must maintain accurate records for all study 
drug destroyed. Records must show the identification and quantity of each unit destroyed, the 
method of destruction, and the person who disposed of the study drug. Upon study completion, 
copies of the study drug accountability records must be filed at the site. Another copy will be 
returned to Gilead. Refer to the pharmacy binder for study drug disposal/return instructions.
The study monitor will review study drug 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 
Gilead’s appointed study monitors to the IRB/IEC/EC, 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.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 77
09 February 2017
9.2.
Sponsor Responsibilities
9.2.1.
Protocol Modifications
Protocol modifications, except those intended to reduce immediate risk to study subjects, may be 
made only by Gilead. The investigator must submit all protocol modifications to the IRB/IEC in 
accordance with local requirements and receive documented IRB/IEC/EC 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 agencies. Gilead 
will ensure that the report meets the standards set out in the ICH Guideline for Structure and 
Content of Clinical Study Reports (ICH E3). Note 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 Gilead in an abstract, 
manuscript, or presentation form or the study has been completed at all study sites for at least 2 
years.
The investigator will submit to Gilead any proposed publication or presentation along with the 
respective scientific journal or presentation forum at least 30 days before submission of the 
publication or presentation. 
No such communication, presentation, or publication will include Gilead’s confidential 
information (see Section 9.1.4).
The investigator will comply with Gilead’s request to delete references to its confidential 
information (other than the study results) in any paper or presentation and agrees to withhold 
publication or presentation for an additional 60 days in order to obtain patent protection if 
deemed necessary.
9.3.
Joint Investigator/Sponsor Responsibilities
9.3.1.
Payment Reporting
Investigators and their study staff may be asked to provide services performed under this 
protocol, e.g. attendance at Investigator's Meetings.  If required under the applicable statutory 
and regulatory requirements, Gilead will capture and disclose to Federal and State agencies any 
expenses paid or reimbursed for such services, including any clinical trial payments, meal, travel 
expenses or reimbursements, consulting fees, and any other transfer of value.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 78
09 February 2017
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 Gilead may conduct inspections or audits of the 
clinical study. If the investigator is notified of an inspection by a regulatory authority the 
investigator agrees to notify the Gilead medical monitor immediately. The investigator agrees to 
provide to representatives of a regulatory agency or Gilead access to records, facilities, and 
personnel for the effective conduct of any inspection or audit.
9.3.4.
Study Discontinuation
Both the sponsor and the investigator reserve the right to terminate the study at any time. Should 
this be necessary, both parties will arrange discontinuation procedures and notify the appropriate 
regulatory authorities, IRBs/ IECs/ECs. In terminating the study, Gilead and the investigator will 
assure that adequate consideration is given to the protection of the subjects’ interests.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 79
09 February 2017
10.
REFERENCES
Graziadei IW, Wiesner RH, Marotta PJ, Porayko MK, Hay JE, Charlton MR, et al. Long-term 
results of patients undergoing liver transplantation for primary sclerosing cholangitis. 
Hepatology 1999;30 (5):1121-7.
Inagaki T, Choi M, Moschetta A, Peng L, Cummins CL, McDonald JG, et al. Fibroblast growth 
factor 15 functions as an enterohepatic signal to regulate bile acid homeostasis. Cell 
metabolism 2005;2 (4):217-25.
Karlsen TH, Franke A, Melum E, Kaser A, Hov JR, Balschun T, et al. Genome-wide association 
analysis in primary sclerosing cholangitis. Gastroenterology 2010;138 (3):1102-11.
Kornfeld D, Ekbom A, Ihre T. Survival and risk of cholangiocarcinoma in patients with primary 
sclerosing cholangitis. A population-based study. Scand J Gastroenterol 1997;32 
(10):1042-5.
Lindor KD, Kowdley KV, Harrison ME, American College of G. ACG Clinical Guideline: 
Primary Sclerosing Cholangitis. Am J Gastroenterol 2015;110 (5):646-59; quiz 60.
Molodecky NA, Kareemi H, Parab R, Barkema HW, Quan H, Myers RP, et al. Incidence of 
primary sclerosing cholangitis: a systematic review and meta-analysis. Hepatology 
2011;53 (5):1590-9.
Mudaliar S, Henry RR, Sanyal AJ, Morrow L, Marschall HU, Kipnes M, et al. Efficacy and 
safety of the farnesoid X receptor agonist obeticholic acid in patients with type 2 diabetes 
and nonalcoholic fatty liver disease. Gastroenterology 2013;145 (3):574-82 e1.
Murakami S, Takayama F, Egashira T, Imao M, Mori A. Fermented papaya preparation halts the 
progression of non-alcoholic steatohepatitis in rats. Journal of Biophysical Chemisty 
2013;4 (2):84-90.
Nakamoto K, Takayama F, Mankura M, Hidaka Y, Egashira T, Ogino T, et al. Beneficial Effects 
of Fermented Green Tea Extract in a Rat Model of Non-alcoholic Steatohepatitis. Journal 
of clinical biochemistry and nutrition 2009;44 (3):239-46.
Pellicciari R, Fiorucci S, Camaioni E, Clerici C, Costantino G, Maloney PR, et al. 6alpha-ethyl-
chenodeoxycholic acid (6-ECDCA), a potent and selective FXR agonist endowed with 
anticholestatic activity. J Med Chem 2002;45 (17):3569-72.
Saich R, Chapman R. Primary sclerosing cholangitis, autoimmune hepatitis and overlap 
syndromes in inflammatory bowel disease. World J Gastroenterol 2008;14 (3):331-7.
Triantos CK, Koukias NM, Nikolopoulou VN, Burroughs AK. Meta-analysis: ursodeoxycholic 
acid for primary sclerosing cholangitis. Aliment Pharmacol Ther 2011;34 (8):901-10.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 80
09 February 2017
11.
APPENDICES
Appendix 1.
Investigator Signature Page
Appendix 2.
Study Procedures Table for GS-US-428-4025
Appendix 3.
CTCAE Grading Scale for Severity of Adverse Events and Laboratory 
Abnormalities
Appendix 4.
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements

GS-9674 
Protocol GS-US-428-4025 
Final 
Gilead Sciences, lnc. 
Amendment 3 
Appendix 1. 
Investigator Signature Page 
GILEAD SCIENCES, INC. 
333 LAKESIDE DRIVE 
FOSTER CITY, CA 94404, 
USA 
STUDY ACKNOWLEDGEMENT 
A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Safety, 
Tolerability, and Efficacy of GS-9674 in Subjects with Primary Sclerosing Cholangitis Without 
Cin-hosis 
GS-US-428-4025, Amendment 3, 09 February 2017 
This protocol has been approved by Gilead Sciences, Inc. The following signature documents 
this approval. 
p p D 
Geor, i.._; 
Georgia Li (Printed) 
Signature 
Medical Monitor 
Date 
INVESTIGATOR STATEMENT 
r 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 wil1 provide all study personnel under my supervision copies of the protocol and access to all 
information provided by Gilead Sciences, Inc. I will discuss this material with them to ensure 
that they are fully informed about the dntgs and the study. 
Principal Investigator Name (Printed) 
Signature 
Date 
Site Number 
CONFIDENT1AL 
Page 81 
09 February 20 17 

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 82
09 February 2017
Appendix 2.
Study Procedures Table for GS-US-428-4025
Blinded Study Phase Treatment Weeks (±3 days)
OLE Weeks 
(±3 days weeks 1-12 and ±5 
days weeks 24-96)
Screening a
Baseline
(Day 1)
Week 1
Week 2
Week 4
Week 8
Week 12 /ET b
Blinded Study Phase 
follow-up visit c
(±5 days)
OLE 
Baseline/Day 1, 
Weeks 1, 2, 4, 8,
12, 24, 36, 48, 60, 
72, 84, 96/ET b
OLE 
follow-up d
Subject Fasting
X
X
X
X
X
X
X
Written Informed 
Consente
X
Review 
Inclusion/Exclusion 
Criteria
X
X
Medical History
X
Partial Mayo Scoref
X
X
X
X
X
X
X
X
X
X
Pruritus VAS &5D-
Itch g
X
X
X
X
X
X
X
X
X
QoL SF-36, PSC-
PRO & PBC-40g
X
X
X
X
Symptom-directed 
PEh
X
X
X
X
X
X
X
X
X
X
Vital Signsi
X
X
X
X
X
X
X
X
X
X
Height and weightj
X
X
X
X
X
X
X
X
X
X
Chemistry
X
X
X
X
X
X
X
X
X
X

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Screening• 
Hematology 
X 
Coagulation Panel 
X 
Cirrhosis 
X 
Assessments 
Lipid Profile 
C-Peptide, 
Hemoglobin A1C 
and Insulin 
Blood for 
X 
Biomarkers k 
Single PK and PD 
Sampling 
HIV-1, HBVand 
X 
HCV Serology 
Pregnancy T estm 
X 
Serum FSH" 
X 
f PD 
12- lead ECGs 
CONFIDENTIAL 
Baseline 
(Day 1) 
Week1 
X 
X 
X 
X 
X 
X 
X 
X 
X 
xt 
X 
X 
X 
X 
Blinded Study Phase Treatment Weeks (±3 days) 
Blinded Study Phase 
follow-up visit c 
Week2 
Week4 
WeekS 
Week 12/ETb 
(±5 days) 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Page 83 
Final 
Amendment 3 
OLE Weeks 
(±3 days weeks 1-12 and ±5 
days weeks 24-96) 
OLE 
Baseline/Day 1, 
Weeks 1, 2, 4, 8, 
12, 24, 36, 48, 60, 
OLE 
72, 84, 96/ET b 
follow-upd 
X 
X 
X 
X 
X 
X 
X 
X 
X 
09 February 2017 
J 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Screening• 
FibroscanP 
MREq 
:tvfRCPr 
Urine drug 
X 
screenmg 
Urine collection 
(Biomarkers)' 
Stool collection 
(BiomarkersY 
pPD 
Dispense GS-9674/ 
PTM GS-9674v 
Concomitant 
X 
Medications 
Adverse Events 
X 
Take GS-9674/ PTM 
GS-9674 Tablets 
CONFIDENTIAL 
Blinded Study Phase Treatment Weeks (±3 days) 
Baseline 
(Day 1) 
Week1 
Week2 
Week4 
WeekS 
Week 12/ETb 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X - Daily (Baseline/ Day 1 to Week 12)w 
Page 84 
Blinded Study Phase 
follow-up visit c 
(±5 days) 
X 
X 
X 
X 
Final 
Amendment 3 
OLE Weeks 
(±3 days weeks 1-12 and ±5 
days weeks 24-96) 
OLE 
Baseline/Day 1, 
Weeks 1, 2, 4, 8, 
12, 24, 36, 48, 60, 
OLE 
72, 84, 96/ET b 
follow-upd 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X-Daily (OLE 
Baseline/ Day 1 
to Week 96) 
09 February 2017 
I 

GS-9674 
Protocol GS-US-428-4025 
Gilead Sciences, Inc. 
Final 
Amendment 3 
a 
The visit window may be extended under special circumstances with explicit approval of the Medical Monitor. Subjects who fail to meet eligibility criteria due to an abnormal 
laboratory result may undergo re-testing of the abnormal analyte during the screening window. This will be done at the discretion of the investigator and also with prior 
approval of the Medical Monitor. 
b 
Blinded Study Phase subjects discontinuing the study at any time for any reason (Early Termination - ET) should complete the procedures listed for the Week 12/ Visit AND 
the follow-up visit. OLE Phase subjects discontinuing the study at any time for any reason (Early Termination- ET) should complete the procedures listed for the Week 96/ 
Visit AND the follow-up visit if possible. 
c 
After completing 12 weeks of treatment in the Blinded Study Phase, subjects will return for the follow-up visit 4 weeks post the last dose of the study drug and at that time 
they can begin their OLE Phase. Follow-up visit for Blinded Study Phase and Baseline/Day 1 OLE visit can occur on the same day if convenient. If OLE Baseline/Day 1 and 
Blinded study follow-Up visit is on the same day subjects should only complete OLE Baseline /Day 1 assessments. 
d 
Follow-up visit should be completed during the Blinded Study Phase as well as the OLE Phase. 
e 
Obtain written informed consent before initiation of any screening procedure. 
f 
Phone follow-up every 4 weeks after OLE Week 12, (OLE Week 16, 20, 28, 32, 40, 44, 52, 56, 64, 68, 76, 80, 88 and 92). 
g 
QoL questionnaires and Pruritus assessments should be completed prior to any study procedures being performed and prior to the subject seeing a health care provider. Refer 
to the Study Reference Binder for guidance on QoL questionnaire administration. During OLE, QoL questionnaires are required at OLE Baseline/Day 1, Weeks 4, 12 and 
every 12 weeks thereafter. 
h 
Complete PE at screening and symptom-directed PE for other visits. The focus of a symptom-driven physical examination will be determined by the investigator based on 
subject complaint. 
Vital signs include (heart rate, systolic and diastolic blood pressure, respiratory rate, and body temperature) 
Height should be collected at Screening and Baseline/Day 1 only. Weight should be collected at all visits. Refer to the Study Reference Binder for specific instructions on 
how weight should be measured. 
k 
Biomarker analyses include, but are not limited to, the tests listed in Section 6.12.1. Some of the blood collected for biomarkers may be stored for future testing. 
1 
PD sampling only at Baseline/Day 1. 
m 
Females of childbearing potential only (see Appendix 4). Serum pregnancy test at Screening and Urine pregnancy tests at all Blinded Study Phase visits, except Week 2, and 
at OLE Baseline/Day 1 and every 4 weeks thereafter. 
~ O~re~redbs=efum~s~~ts-~e ~pe=n~di~·x~4~-~------------------------------~ 
p 
q 
r 
s 
t 
p D 
v 
w 
Sul.iJect shoiilCI lie m fasted state tor Fil.iroScan®Collection. Refer to tfie study reference l.imcterfor l:iiTllier Cletmls. If FibroScan 1s not avmlable a a site the test may be 
omitted. 
Should be in a fasted state for MRE scan. Refer to study reference binder for further details. If MRE is not available at a site the test may be omitted. MRE scan should be 
performed at Blinded Study Phase Baseline/Day 1 and OLE Weeks 48 and 96. 
MRCP is to be performed at Blinded Study Phase Baseline/Day 1 and OLE Weeks 48 and 96. Refer to study reference binder for further details. 
Urine Biomarker sample collection at OLE Baseline/Day 1, Weeks 24, 48, 72 and 96 only. 
Stool sample collection at Blinded Study Phase Baseline/Day 1, Week 12 and at the Follow up and Early term visits. Stool sample collection during OLE at OLE 
Baseline/Day 1, Week 48 and Week 96 visit 
[ 
. -
. 
. 
. 
. 
Study drug Will be ass1gned vw the IWRS system every 4 weeks from Baselme/Day 1 through Week 8m Blmd Study Phase and at OLE Baselme/Day 1, Weeks 1, 4, 8 12 and 
every 12 weeks thereafter. 
Subjects to self-administer the study drug at the investigative site at the conclusion of the Blinded Study Phase Baseline/Day 1 and Week 12 visit. 
CONFIDENTIAL 
Page 85 
09 February 2017 

GS-9674
Protocol GS-US-428-4025
Final 
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 86
09 February 2017
Appendix 3.
CTCAE Grading Scale for Severity of Adverse Events and 
Laboratory Abnormalities
http://evs.nci.nih.gov/ftp1/CTCAE/CTCAE_4.03_2010-06-14_QuickReference_8.5x11.pdf

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 87
09 February 2017
Appendix 4.
Pregnancy Precautions, Definition for Female of Childbearing 
Potential, and Contraceptive Requirements
1. Definitions
a. Definition of Childbearing Potential
For the purposes of this study, a female born subject is considered of childbearing potential 
following the initiation of puberty (Tanner stage 2) until becoming post-menopausal, unless 
permanently sterile or with medically documented ovarian failure.  
Women are considered to be in a postmenopausal state when they are > 54 years of age with 
cessation of previously occurring menses for > 12 months without an alternative cause.  In 
addition, women of any age with amenorrhea of > 12 months may also be considered 
postmenopausal if their follicle stimulating hormone (FSH) level is in the postmenopausal range 
and they are not using hormonal contraception or hormonal replacement therapy.
Permanent sterilization includes hysterectomy, bilateral oophorectomy, or bilateral 
salpingectomy in a female subject of any age.
b. Definition of Male Fertility
For the purposes of this study, a male born subject is considered of fertile after the initiation of 
puberty unless permanently sterile by bilateral orchidectomy or medical documentation.
2. Contraception Requirements for Female Subjects
a. Study Drug Effects on Pregnancy and Hormonal Contraception
GS-9674 has not yet been studied in pregnant women. In the initial dose range-finding studies in 
pregnant mice and rabbits, there were no effects on embryofetal development other than a 
decrease in fetal body weights in pregnant rabbits administered 1000 mg/kg/day. The decrease in 
fetal body weights are likely secondary to maternal toxicity rather than a direct effect of 
GS-9674. The NOEL for embryo/fetal development is 300 mg/kg/day in mice and 
200 mg/kg/day in rabbits. These doses were associated with exposures that are > 50-fold higher 
than the anticipated human exposure at the maximum proposed human dose of 100 mg once 
daily. Drug-drug interaction (DDI) data do not suggest a potential for interaction with hormones 
used for contraception.
Please refer to the latest version of the Investigator’s Brochure for additional information.

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 88
09 February 2017
b. Contraception Requirements for Female Subjects of Childbearing Potential
The inclusion of female subjects of childbearing potential requires the use of highly effective 
contraceptive measures. They must have a negative serum pregnancy test at Screening and a 
negative pregnancy test on the Baseline/Day 1 visit prior to randomization. At minimum, a 
pregnancy test will be performed at all study visits except Blinded Study Phase Week 2 and OLE 
Weeks 1 and 2 and at 30 days after the last dose of the study drug.  Female subjects must agree 
to one of the following from Screening until 30 days following the last dose of the study drug 
GS-9674.

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)
Or

Consistent and correct use of one hormonal method and one barrier method.
Barrier methods
■
Diaphragm with spermicide
■
Cervical cap with spermicide
■
Male condom (with or without spermicide)
Hormonal methods
■
Oral contraceptives (either combined or progesterone only)
■
Injectable progesterone
■
Implants of levonorgestrel
■
Transdermal contraceptive patch
■
Contraceptive vaginal ring

GS-9674
Protocol GS-US-428-4025
Final
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 89
09 February 2017
Female subjects must also refrain from egg donation and in vitro fertilization during treatment 
and until at least 30 days after the last dose of the study drug GS-9674.
3. Contraception Requirements for Male Subjects
It is theoretically possible that a relevant systemic concentration may be achieved in a female 
partner from exposure of the male subject’s seminal fluid.  Therefore, male subjects with female 
partners of childbearing potential must use condoms (plus spermicide) during treatment and until 
90 days after last dose of GS-9674. Additional contraception recommendations should also be 
considered if the female partner is not pregnant.
Male subjects must agree to avoid sperm donation during treatment and until at least 90 days 
after the last dose of study drug GS-9674.
4. Unacceptable Birth Control Methods
Birth control methods that are unacceptable include periodic abstinence (e.g., calendar, 
ovulation, symptothermal, post-ovulation methods), withdrawal (coitus interruptus), spermicides 
only, and lactational amenorrhea method (LAM).  Female condom and male condom should not 
be used together.
5. Procedures to be Followed in the Event of Pregnancy
Subjects will be instructed to notify the investigator if they become pregnant at any time during 
the study, or if they become pregnant within 30 days (90 days of partner of male subject) 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. 
Subjects whose partner has become pregnant or suspects she is pregnant during the study must 
report the information to the investigator. Instructions for reporting pregnancy, partner 
pregnancy, and pregnancy outcome are outlined in Section 7.6.2.1.