A Phase 1b/2a Study in Participants With Early Stage COVID-19 to Evaluate the Safety, Efficacy, and Pharmacokinetics of Remdesivir Administered by Inhalation
Phase: PHASE1
Conditions: COVID-19
Sponsor: Gilead Sciences

CLINICAL STUDY PROTOCOL
Study Title:
A Phase 1b/2a Study in Participants with Early Stage COVID-19 to 
Evaluate the Safety, Efficacy, and Pharmacokinetics of Remdesivir
Administered by Inhalation
Sponsor:
Gilead Sciences, Inc.
333 Lakeside Drive
Foster City, CA 94404
IND Number:
EudraCT Number:
Clinical Trials.gov 
Identifier:
150732
Not Applicable
NCT04539262
Indication:
COVID-19
Protocol ID:
GS-US-553-9020
Contact Information:
The medical monitor name and contact information will be 
provided on the Key Study Team Contact List.
Protocol 
Version/Date:
Original:
31 July 2020
Amendment 1:
26 August 2020
Amendment 2: 
14 December 2020
Amendment 3:
13 January 2021
This study will be conducted under US Food & Drug Administration investigational new drug 
(IND) regulations (21 Code of Federal Regulations Part 312); however, sites located in the 
European Economic Area and Switzerland are not included under the IND and are considered 
non-IND sites.
CONFIDENTIALITY STATEMENT
The information contained in this document, particularly unpublished data, is the property or 
under control of Gilead Sciences, Inc., and is provided to you in confidence as an investigator, 
potential investigator, or consultant, for review by you, your staff, and an applicable 
Institutional Review Board or Independent Ethics Committee. The information is only to be 
used by you in connection with authorized clinical studies of the investigational drug 
described in the protocol. You will not disclose any of the information to others without 
written authorization from Gilead Sciences, Inc., except to the extent necessary to obtain 
informed consent from those persons to whom the drug may be administered.
(rJ GILEAiJ 

Remdesivir (RDV; GS-5734T") 
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TABLE OF CONTENTS 
TABLE OF CONTENTS .............................................................................................................................................. 2 
PROTOCOL SYNOPSIS .............................................................................................................................................. 5 
GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS .................................................................... 13 
I. 
INTRODUCTION .............................................................................................................................................. 16 
1.1. 
Background ............................................................................................................................................ 16 
1.2. 
Remdesivir (ROY; GS-5734) for Inhaled Administration ..................................................................... 16 
1.2.1. 
General Information ............................................................................................................. 16 
1.2.2. 
Additional Clinical Studies of Remdesivir ........................................................................... 17 
1.2.3. 
Rationale for This Study ....................................................................................................... 18 
1.3. 
Rationale for the Dose Selection ............................................................................................................ 19 
1.4. 
Risk/Benefit Assessment for the Study .................................................................................................. 20 
1.5. 
Compliance ............................................................................................................................................ 2 1 
2. 
OBJECTIYES ..................................................................................................................................................... 22 
3. 
STUDY DESIGN ................................................................................................................................................ 23 
3.1. 
3.2. 
3.3. 
3.4. 
3.5. 
3.6. 
3.7. 
3.8. 
3.9. 
Endpoints ............................................................................................................................................... 23 
Study Design .......................................................................................................................................... 24 
Study Treatments ................................................................................................................................... 24 
Safety Review Team .............................................................................................................................. 26 
Duration ofTreatment ............................................................................................................................ 27 
Discontinuation Criteria ......................................................................................................................... 27 
End of Study ........................................................................................................................................... 27 
Poststudy Care ........................................................................................................................................ 27 
Source Data ............................................................................................................................................ 28 
4. 
SUBJECT POPULATION .................................................................................................................................. 29 
4.1. 
Number of Subjects and Subject Selection ............................................................................................ 29 
4.1.1. 
Subject Replacement ............................................................................................................ 29 
4.2. 
Inclusion Criteria .................................................................................................................................... 29 
4.3. 
Exclusion Criteria ................................................................................................................................... 29 
5. 
INYESTIGATIONAL MEDICINAL PRODUCTS ........................................................................................... 3 1 
5.1. 
Randomization, Blinding, and Treatment Codes Access ....................................................................... 3 1 
5.1.1. 
Randomization ..................................................................................................................... 3 1 
5.1.2. 
Blinding ................................................................................................................................ 3 1 
5.1.3. 
Procedures for Breaking Treatment Codes ........................................................................... 32 
5.2. 
Description and Handling of Remdesivir ............................................................................................... 32 
5.2.1. 
Formulation .......................................................................................................................... 32 
5.2.2. 
Packaging and Labeling ....................................................................................................... 33 
5.2.3. 
Storage and Handling ........................................................................................................... 33 
5.3. 
Dosage and Administration of Remdesivir ............................................................................................ 34 
5.4. 
Dispensing, Accountability, and Disposal or Return of Study Treatment .............................................. 34 
5.5. 
Prior and Concomitant Medications ....................................................................................................... 35 
6. 
STUDY PROCEDURES .................................................................................................................................... 36 
6.1. 
Subject Enrollment and Treatment Assignment ..................................................................................... 36 
6.2. 
Pretreatment Assessments ...................................................................................................................... 36 
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6.2.1.
Study Parts A, B, and C: Screening Visit.............................................................................36
6.2.2.
Study Parts A and B: Baseline/Day 1 Assessments..............................................................37
6.3.
Study Parts A and B: Daily Study Assessments (Days 2-5)...................................................................38
6.4.
Study Parts A and B: Follow-Up Assessments (Days 7 and 14)............................................................39
6.5.
Study Parts A and B: Day 28 Follow-Up Assessment (± 5 days) ..........................................................40
6.6.
Study Part C: Baseline/Day 1, Days 3, 5, and 7 Assessments................................................................40
6.7.
Study Part C: Days 2 and 4 Assessments...............................................................................................41
6.8.
Study Part C: Follow-Up Assessments (Days 14 and 28)......................................................................41
6.9.
Chest X-Ray...........................................................................................................................................42
6.10.
FEV1.......................................................................................................................................................42
6.11.
Clinical Laboratory Assessments ...........................................................................................................42
6.12.
Pharmacokinetic Assessments................................................................................................................43
6.13.
Assessments for Early Discontinuation from Study...............................................................................43
6.13.1.
Criteria for Discontinuation of Study Treatment..................................................................43
6.14.
End of Study...........................................................................................................................................44
6.15.
Poststudy Care........................................................................................................................................44
6.16.
Sample Storage.......................................................................................................................................44
7.
ADVERSE EVENTS AND TOXICITY MANAGEMENT...............................................................................45
7.1.
Definitions of Adverse Events and Serious Adverse Events..................................................................45
7.1.1.
Adverse Events.....................................................................................................................45
7.1.2.
Serious Adverse Events........................................................................................................45
7.1.3.
Study Treatments and Gilead Concomitant Therapy Special Situations 
Reports .................................................................................................................................46
7.2.
Assessment of Adverse Events and Serious Adverse Events.................................................................47
7.2.1.
Assessment of Causality for Study Treatments and Procedures...........................................47
7.2.2.
Assessment of Severity ........................................................................................................47
7.3.
Investigator Requirements and Instructions for Reporting Adverse Events and Serious 
Adverse Events.......................................................................................................................................48
7.3.1.
Requirements for Collection Prior to Study Treatment Initiation ........................................48
7.3.2.
Adverse Events.....................................................................................................................48
7.3.3.
Serious Adverse Events........................................................................................................48
7.3.4.
Study Treatment Special Situations Reports ........................................................................48
7.3.5.
Concomitant Therapy Reports..............................................................................................49
7.4.
Reporting Process for Serious Adverse Events and Special Situation Reports......................................49
7.4.1.
Serious Adverse Event Reporting Process ...........................................................................49
7.4.2.
Special Situations Reporting Process ...................................................................................50
7.5.
Gilead Reporting Requirements.............................................................................................................51
7.6.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as Adverse Events or 
Serious Adverse Events..........................................................................................................................52
7.7.
Toxicity Management ............................................................................................................................52
8.
STATISTICAL CONSIDERATIONS................................................................................................................54
8.1.
Analysis Objectives and Endpoints........................................................................................................54
8.1.1.
Analysis Objectives..............................................................................................................54
8.1.2.
Primary Endpoint .................................................................................................................54
8.1.3.
Secondary Endpoint .............................................................................................................54
8.2.
Planned Analyses ...................................................................................................................................55
8.2.1.
Interim Analysis ...................................................................................................................55
8.2.2.
Final Analysis.......................................................................................................................56
8.3.
Analysis Conventions.............................................................................................................................56
8.3.1.
Analysis Sets ........................................................................................................................56
8.3.2.
Data Handling Conventions .................................................................................................56
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8.4.
Demographic and Baseline Characteristics Analysis .............................................................................57
8.5.
Efficacy Analysis ...................................................................................................................................57
8.5.1.
Primary Analysis..................................................................................................................57
8.5.2.
Secondary Analyses .............................................................................................................57
8.6.
Safety Analysis.......................................................................................................................................57
8.6.1.
Extent of Exposure...............................................................................................................57
8.6.2.
Adverse Events.....................................................................................................................57
8.6.3.
Laboratory Evaluations ........................................................................................................58
8.7.
Adjustments for Multiplicity..................................................................................................................58
8.8.
Pharmacokinetic Analysis......................................................................................................................58
8.9.
Sample Size............................................................................................................................................58
9.
RESPONSIBILITIES..........................................................................................................................................59
9.1.
Investigator Responsibilities ..................................................................................................................59
9.1.1.
Good Clinical Practice..........................................................................................................59
9.1.2.
Financial Disclosure.............................................................................................................59
9.1.3.
Institutional Review Board/Independent Ethics Committee Review and 
Approval...............................................................................................................................59
9.1.4.
Informed Consent.................................................................................................................59
9.1.5.
Confidentiality......................................................................................................................60
9.1.6.
Study Files and Retention of Records ..................................................................................60
9.1.7.
Case Report Forms...............................................................................................................62
9.1.8.
Investigator Inspections........................................................................................................62
9.1.9.
Protocol Compliance............................................................................................................62
9.2.
Sponsor Responsibilities ........................................................................................................................62
9.2.1.
Protocol Modifications.........................................................................................................62
9.2.2.
Study Report and Publications .............................................................................................63
9.3.
Joint Investigator/Sponsor Responsibilities ...........................................................................................63
9.3.1.
Payment Reporting...............................................................................................................63
9.3.2.
Access to Information for Monitoring..................................................................................63
9.3.3.
Access to Information for Auditing or Inspections ..............................................................64
9.3.4.
Study Discontinuation..........................................................................................................64
10.
REFERENCES ...................................................................................................................................................65
11.
APPENDICES ....................................................................................................................................................66
Appendix 1.
Investigator Signature Page....................................................................................................67
Appendix 2.
Pandemic Risk Assessment and Mitigation Plan....................................................................68
Appendix 3.
Study Procedures Tables ........................................................................................................71
Appendix 4.
Management of Clinical and Laboratory Adverse Events......................................................75
Appendix 5.
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements...................................................................................................76

Remdesivir (RDV; GS-5734T") 
Protocol GS-US-553-9020 
Gilead Sciences, Inc. 
Study Title: 
IND Number: 
EudraCT Number: 
Clinical Trials.gov 
Identifier: 
Study Centers 
Planned: 
Objectives: 
CONFIDENTIAL 
PROTOCOL SYNOPSIS 
Gilead Sciences, Inc. 
333 Lakeside Drive 
Foster City, CA 94404 
FINAL 
Amendment3 
A Phase 1b/2a Study in Participants with Early Stage COVID-19 to 
Evaluate the Safety, Efficacy, and Phannacokinetics of Remdesivir 
Administered by Inhalation 
150732 
Not Applicable 
NCT04539262 
Up to approximately 50 centers globally 
The primary objective of this study is: 
• 
To characterize the impact of inhaled remdesivir (RDV) on severe 
acute respiratory syndrome (SARS)-coronavirus (CoV)-2 viral 
load in participants with early stage corona virus disease 2019 
(COVID-19) 
The secondary objectives of this study are: 
• 
To evaluate the safety and tolerability of inhaled Remdesivir for 
Injection fonnulation in participants with early stage COVID-19 
• 
To evaluate the phannacokinetics (PK) of inhaled Remdesivir for 
Injection fonnulation and its metabolites in participants with early 
stage COVID-19 in Parts A and B 
• 
To characterize and evaluate disease progression from baseline 
• 
To characterize the efficacy, safety, and tolerability of Remdesivir 
for Inhalation Solution fonnulation administered with a 
mouthpiece in Part C of the study 
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Study Design:
This is a Phase 1b/2a randomized, blinded, placebo-controlled, 
multicenter study of RDV therapy for outpatients with early stage 
COVID-19 evaluating inhaled RDV (treatment arm) or 
placebo-to-match (PTM) (placebo arm).
The study will feature multiple parts: Part A, Part B, and Part C.
The goal of the study is to evaluate the safety, efficacy, and PK of 
inhaled RDV in participants with early stage COVID-19. Parts A and 
B of the study will evaluate 2 different nominal dosing regimens 
(31 mg in Part A and 62 mg in Part B [Remdesivir for Injection 
formulation]) for up to 5 days of daily dosing. Safety and efficacy of 
an inhaled RDV formulation with reduced sulfobutylether 
β-cyclodextrin sodium (SBECD) content (Remdesivir for Inhalation 
Solution formulation) will be evaluated in Part C of the study. The 
RDV formulation used within each Study Part is as follows:
Study 
Part
Formulation
Volume/Nominal 
Dose (mg)
Duration of 
Nebulization 
(minutes)
Part A
Remdesivir for Injection 
formulation via nebulization
31 mga
17 minutes
Part B
Remdesivir for Injection 
formulation via nebulization
62 mga
34 minutes
Part C
Remdesivir for Inhalation 
Solution formulation via 
nebulization
39 mgb
19 minutes 
a
Sealed Facemask: Nominal dose of 31 mg and 62 mg to achieve a deposited dose of 5 mg
and 10 mg, respectively: Overall delivery efficiency  16.1%.
b
Mouthpiece: Nominal dose of 39 mg to achieve a deposited dose of 10 mg: Overall 
delivery efficiency  25.6%.
The term “inhaled remdesivir” refers to both the Remdesivir for 
Injection formulation and Remdesivir for Inhalation Solution
formulation when administered via nebulization using the LC Sprint. 
Part A: In Part A, approximately 36 participants who meet all 
eligibility criteria will be randomized in a 1:1:1 ratio into one of the 
following 3 treatment groups:
Treatment Group 1: 31 mg inhaled Remdesivir for Injection 
formulation daily for 5 days
Treatment Group 2: 31 mg inhaled Remdesivir for Injection 
formulation daily for 3 days followed by PTM daily for 2 days
Treatment Group 3: PTM daily for 5 days

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Part B: In Part B, if supported by evaluation in healthy volunteers in 
the Phase 1a study, an additional 36 total participants may be 
randomized in a 1:1:1 ratio into one of the following 3 treatment 
groups:
Treatment Group 4: 62 mg inhaled Remdesivir for Injection 
formulation daily for up to 5 days
Treatment Group 5: 62 mg inhaled Remdesivir for Injection 
formulation daily for up to 3 days followed by PTM daily through 
Day 5
Treatment Group 6: PTM daily for 5 days
Part C: Part C of the study will include an expanded safety and 
efficacy assessment of an additional 80 participants. Participants in 
Part C will be enrolled after review of preliminary safety data from 
Parts A and B through at least Day 7. Approximately 80 participants 
will be randomized in a 3:1 ratio into one of the following 2 treatment 
groups: 
Treatment Group 7: 39 mg Remdesivir for Inhalation Solution 
formulation once daily for 5 days by mouthpiece
Treatment Group 8: PTM daily for 5 days by mouthpiece
Number of 
Participants 
Planned:
Part A and Part B: Approximately 36 participants will be enrolled in 
each part.
Part C: Approximately 80 participants will be enrolled.
Target Population:
Parts A and B: Participants ≥18 years of age with polymerase chain 
reaction (PCR)-confirmed early stage COVID-19
Part C: Participants ≥18 years of age with early stage COVID-19
confirmed by nucleic acid testing or direct antigen testing
Duration of 
Treatment:
RDV and/or PTM will be administered for 5 days.
Diagnosis and 
Main Eligibility 
Criteria:
Eligible participants will be at least 18 years of age who meet the 
following eligibility criteria:
Key Inclusion Criteria:

Willing and able to provide written informed consent, or with a 
legal representative who can provide informed consent

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
infection first confirmed by PCR (Parts A and B) or by nucleic 
acid testing or direct antigen testing (Part C) with sample collected 
≤ 4 days prior to randomization

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
COVID-19 symptom onset ≤ 7 days prior to randomization

Oxygen saturation as measured by pulse oximetry (SpO2) > 94% 
on room air
Key Exclusion Criteria:

Ongoing or prior participation in any other clinical trial of an 
experimental vaccine or treatment for COVID-19

Prior or current hospitalization for COVID-19 or need for 
hospitalization

Treatment of COVID-19 with other agents with actual or possible 
direct antiviral activity against SARS-CoV-2 including IV RDV or 
administration of any SARS-CoV-2 (or COVID-19) vaccine
Patients chronically administered chloroquine or 
hydroxychloroquine for any reason are to be excluded

Requiring oxygen supplementation

Positive pregnancy test

Breastfeeding female

Known hypersensitivity to the study treatment, its metabolites, or 
formulation excipient

Pre-existing pulmonary conditions such as chronic obstructive 
pulmonary disease or asthma (Parts A and B only)
Study Procedures/
Frequency:
At screening, after the participant has provided informed consent, 
assessments will include but are not limited to the following: 
demographic and baseline characteristics, medical history, and 
concomitant medications will be documented. Body weight and height 
will be measured. A urine pregnancy test will be performed for women 
of childbearing potential. Vital signs including heart rate, temperature, 
blood pressure, and SpO2 will be recorded. A complete physical 
examination will be performed.
Study Parts A and B:
On Days 1 through 5, assessments will include a symptom-directed 
physical examination. A 12-lead electrocardiogram (ECG) will be 
performed at Day 1. Vital signs will be measured predose and 
postdose. Concomitant medications and adverse events (AEs) will be 
documented. Laboratory samples will be obtained for safety 
assessments (Days 1, 3, 5) and PK assessments (Days 1, 3, 5).
Nasopharyngeal, oropharyngeal swab samples and saliva samples for 
SARS-CoV-2 testing and possible viral resistance testing will be 
performed on Days 1 through 5. A chest x-ray will be performed at
Day 1 to identify any pulmonary infiltrates. Forced expiratory volume 

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in the first second of expiration (FEV1) will be performed daily during 
treatment days and will be performed both predose and 10 minutes 
postdose. Repeat FEV1 should be performed at 30 minutes postdose if 
there is > 15% reduction in FEV1 at 10 minutes postdose compared 
with the same day predose FEV1. FEV1 assessment may also be 
performed if there is a clinical concern of bronchospasm. Inhaled 
Remdesivir for Injection formulation or PTM will be administered at 
Days 1 through 5. If Day 1 assessments are performed on the same day 
as the screening assessments, procedures need not be repeated.
Participants will complete the adapted InFLUenza Patient-Reported 
Outcome (FLU-PRO©) questionnaire daily (Days 1-14).
On Days 7 and 14, assessments will include a symptom-directed 
physical examination. Vital signs will be measured, concomitant 
medications and AEs will be documented. Laboratory samples will be 
obtained for safety assessments, single PK assessment (Day 7), and 
nasopharyngeal and oropharyngeal swab samples and saliva samples 
for SARS-CoV-2 testing and possible viral resistance testing.
On Day 28, assessments will include review of AEs and concomitant 
medications. The Day 28 follow-up assessments may be completed by 
telephone.
If supported by review of at least 7-day safety data from participants in 
Parts A and B, then the Remdesivir for Inhalation Solution formulation 
will be evaluated in Part C.
Pharmacokinetic Assessments:
Sparse plasma PK assessments will be conducted in all participants at 
selected sites in Parts A and B. Sparse plasma PK samples will be 
collected at Day 1 (end of nebulization, 
 
) and Day 3 (predose and end of nebulization).
Up to 6 participants/group in Part A and Part B will have intensive PK 
assessments. Intensive PK samples will be collected at Day 1 and an 
additional collection, either at Day 3 or Day 5, at the following time 
points relative to the end of nebulization: 0 (predose), 0.25, 0.5, 0.75, 
1, 1.5, 2, 4, and 24 hours post end of nebulization. An additional single 
PK sample will be collected on Day 7 visit for subjects who participate 
in the intensive PK assessments.
Study Part C:
Remdesivir for Inhalation Solution formulation or PTM will be 
administered Days 1 through 5 with telehealth support as needed.
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On Days 1, 3, 5, and 7, assessments will include a symptom-directed 
physical examination. Nasopharyngeal, oropharyngeal swab samples 
and saliva samples for SARS-CoV-2 testing and possible viral 
resistance testing will be collected predose with the assistance of home 
nursing on Days 1, 3, 5, and 7. Vital signs will be performed predose 
on Days 1, 3, and 5 and on Day 7. Concomitant medications and AEs 
will be documented. Laboratory samples will be obtained for safety 
assessments predose on Days 1, 3, 5, and 7. Plasma samples will be 
obtained for PK assessments predose on Days 3 and 5 and Day 7 
(anytime sample) in all participants.
Participants will complete the adapted FLU-PRO© questionnaire daily 
(Days 1-14).
FEV1 will be performed daily during treatment days and will be 
performed both predose and 10 minutes postdose. Repeat FEV1 should 
be performed at 30 minutes postdose if there is > 15% reduction in 
FEV1 at 10 minutes postdose compared with the same day predose 
FEV1. FEV1 assessment may also be performed if there is a clinical 
concern of bronchospasm.
On Days 14 and 28, assessments will include review of AEs and 
concomitant medications. The Day 14 and 28 follow-up assessments 
may be completed by telephone.
Test Product, Dose, 
and Mode of 
Administration:
In Part A and Part B, the Remdesivir for Injection formulation 
delivered by inhalation, will be used. In Part C, the Remdesivir for 
Inhalation Solution formulation will be used.
Part A: 31 mg (nominal dose) Remdesivir for Injection administered 
via inhalation once daily at approximately the same time each day
Part B: 62 mg (nominal dose) Remdesivir for Injection administered 
via inhalation once daily at approximately the same time each day
Part C: 39 mg (nominal dose) by mouthpiece of Remdesivir for 
Inhalation Solution formulation administered via inhalation once daily 
at approximately the same time each day
Reference Therapy, 
Dose, and Mode of 
Administration:
Placebo administered via inhalation once daily at approximately the 
same time each day
Criteria for 
Evaluation:
Safety:
Proportion of participants with treatment-emergent AEs and laboratory
abnormalities.

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Efficacy: 
Change in SARS-CoV-2 viral load will be measured. A FLU-PRO© 
questio1maire will be utilized to report COVID-19 symptom severity 
and duration. Disease progression from baseline will be assessed by 
duration and change in severity of COVID-19 clinical symptoms and 
need for medically attended visits (MA Vs). 
Pharmacokinetics: 
For Parts A and B, the plasma concentrations of inhaled RDV and its 
metabolites will be measured, as appropriate. The following plasma 
PK parameters will be calculated for each analyte (RDV, GS-441524 
and GS-704277), as applicable: AUCo 24h AUC1au AUC1as1 CLsslF t,12, 
Statistical Methods: 
No statistical sample size/power calculation was perfonned as the 
sample size of up to approximately 152 participants is deemed feasible 
and sufficient to provide a descriptive assessment of viral kinetics, 
safety and tolerability, PK and disease progression in this study. 
CONFIDENTIAL 
Antiviral activity evaluation will be based on time weighted average 
change in SARS-CoV-2 viral load (defined as the AUC of viral load 
change divided by time between baseline to Day 7) and will be 
summarized by treatment group and each RDV group compared with 
placebo. 
Safety: 
Adverse event data will be listed by participant. Adverse events 
leading to study treatment discontinuation, treatment-emergent AEs, 
and serious AEs will be summarized by treatment, system organ class, 
and preferred tenn using the Medical Dictionary for Regulatory 
Activities (MedDRA). 
Listings of individual participants laboratory results and change from 
predose values for selected laboratory values will be summarized by 
treatment. 
Incidence of treatment-emergent laboratory abnonnalities will be 
smmnarized by treatment. 
Vital signs and ECG data will be smmnarized by treatment. 
FEY, values will be smmnarized by treatment. 
Listings of individual participants progression of COVID-19 
symptoms as reported by adapted FLU-PRO© questio1maire will be 
smmnarized by treatment. 
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PK: 
FINAL 
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For Parts A and B, plasma PK parameters for inhaled RDV and its 
metabolites will be summarized by treatment group using descriptive 
statistics (including mean, geometric mean, median, minimmn, 
maximum, and sample size). Concentrations of inhaled RDV and its 
metabolites in lasma over time will be smmnarized. 
This study will be conducted in accordance with the guidelines of Good Clinical Practice (GCP) 
including archiving of essential documents. 
CONFIDENTIAL 
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GLOSSARY OF ABBREVIATIONS AND DEFINITION OF TERMS
λz
terminal elimination rate constant, estimated by linear regression of the terminal 
elimination phase of the log concentration of drug versus time curve of the drug
%AUCexp
percentage of AUC extrapolated between AUClast and AUCinf
AE
adverse event
ALT
alanine aminotransferase 
ARDS
acute respiratory distress syndrome
AST
aspartate aminotransferase 
ATP
adenosine triphosphate
AUC
area under the concentration versus time curve
AUCinf
area under the concentration versus time curve extrapolated to infinite time, calculated as 
AUClast + (Clast/λz)
AUClast
area under the concentration versus time curve from time zero to the last quantifiable 
concentration
AUCtau
area under the concentration versus time curve over the dosing interval
CI
confidence interval
CLss/F
apparent oral clearance at steady state after administration of the drug:
CLss/F = Dose/AUCtau, where “Dose” is the dose of the drug
Clast
last observed quantifiable concentration of the drug
CLcr
creatinine clearance
Cmax
maximum observed concentration of drug
COPD
chronic obstructive pulmonary disease
COVID-19
coronavirus disease 2019
CoV
coronavirus
CRF
case report form
Ctau
observed drug concentration at the end of the dosing interval
DAIDS
Division of AIDS
ECG
electrocardiogram
eCRF
electronic case report form
EDC
electronic data capture
EudraCT
European Clinical Trials Database
EU
European Union
EUA
Emergency Use Authorization
FDA
Food and Drug Administration
FEV1
forced expiratory volume in the first second of expiration
FLU-PRO©
InFLUenza Patient-Reported Outcome
FSH
follicle-stimulating hormone
GCP
Good Clinical Practice
Gilead
Gilead Sciences, Inc.
GLPS
Global Patient Safety

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IB
investigator’s brochure
ICF
informed consent form
ICH
International Council on Harmonisation (of Technical Requirements for Registration of 
Pharmaceuticals for Human Use)
IEC
independent ethics committee
IND
investigational new drug 
IRB
institutional review board
IUD
intrauterine device
IV
intravenous
IXRS
interactive voice/web response system
LLOQ
lower limit of quantitation
MAV
medically attended visit
MedDRA
Medical Dictionary for Regulatory Activities
MERS
Middle East respiratory syndrome
NOAEL
no observed adverse effect level
PCR
polymerase chain reaction
PI
principal investigator
PK
pharmacokinetic(s)
PT
preferred term
PTM
placebo-to-match
PVE
Pharmacovigilance and Epidemiology
RDV
remdesivir (GS-5734™)
RNA
ribonucleic acid
RT-qPCR
quantitative reverse transcriptase polymerase chain reaction
SAE
serious adverse event 
SARS
severe acute respiratory syndrome
SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
SBECD
sulfobutylether β-cyclodextrin sodium
SDV
source data verification
SpO2
oxygen saturation as measured by pulse oximetry
SOC
standard of care
SOP
standard operating procedure
SRT
safety review team
SSR
special situation report
SUSAR
suspected unexpected serious adverse reaction
TEAE
treatment-emergent adverse event
Tlast
time (observed time point) of Clast
Tmax
the time (observed time point) of Cmax
t1/2
estimate of the terminal elimination half-life of the drug, calculated by dividing the natural 
log of 2 by the terminal elimination rate constant (λz)

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ULN
upper limit of normal
US
United States
Vz/F
apparent volume of distribution of the drug

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1.
INTRODUCTION
1.1.
Background
Coronaviruses (CoVs) are positive-sense, single-stranded, enveloped RNA viruses, many of 
which are commonly found in humans and cause mild symptoms. However, over the past 
2 decades, emerging pathogenic CoVs that can cause life-threatening disease in humans and 
animals have been identified, namely severe acute respiratory syndrome coronavirus 
(SARS-CoV;{de Wit 2016, Ksiazek 2003}), Middle Eastern respiratory syndrome coronavirus 
(MERS-CoV; {Assiri 2013, Choi 2016, Who Mers-Cov Research Group 2013}), and severe 
acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus 
disease 2019 (COVID-19; {Zhu 2020}). Coronaviruses are known to have high mutation and 
recombination rates, which may allow them to cross species barriers and adapt to new hosts {Lau 
2015}. Bats are reservoir hosts for many types of CoVs and are thought to have spread emerging 
CoVs to new species. Cross-species transmission to animals and subsequent zoonotic 
transmission has resulted in disease in humans {de Wit 2016}.
SARS-CoV-2, a single-stranded RNA virus, is identified as the cause of an outbreak of 
respiratory illness that was first detected in Wuhan, China in December 2019. The virus has now 
spread globally, resulting in a global pandemic and causing severe respiratory illness throughout 
the world. Severe cases progress to pneumonia and multi-organ failure, which can lead to death. 
Gilead Sciences, Inc. (Gilead) has been working closely with global health authorities to respond 
to the ongoing pandemic and to evaluate the utility of intravenous (IV) remdesivir (RDV; 
GS-5734™) as a treatment option for COVID-19. Supported by Phase 3 clinical studies, IV
RDV has been approved for treatment of COVID-19 in Japan, the European Union (EU), the 
United States (US), and other countries.
1.2.
Remdesivir (RDV; GS-5734) for Inhaled Administration
Remdesivir is being developed by Gilead and is formulated for IV administration and for 
administration via nebulization.
1.2.1.
General Information
Remdesivir is an adenosine nucleotide prodrug that distributes into cells where it is metabolized
to form the pharmacologically active nucleoside triphosphate metabolite. Metabolism of
remdesivir to remdesivir triphosphate has been demonstrated in multiple cell types. Remdesivir
triphosphate acts as an analog of adenosine triphosphate (ATP) and competes with the natural
ATP substrate for incorporation into nascent RNA chains by the SARS-CoV-2 RNA-dependent
RNA polymerase, which results in inhibition of viral replication.
For further information on RDV, refer to the investigator’s brochure (IB) for RDV. 

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1.2.2.
Additional Clinical Studies of Remdesivir
1.2.2.1.
GS-US-553-9018 Inhaled Remdesivir Phase 1a Study
Study GS-US-553-9018 is an ongoing randomized, blinded, placebo-controlled, single- and 
multiple-dose study with staggered dose escalation and adaptive dose selection evaluating 
inhaled RDV. In each cohort, 10 healthy male and nonpregnant, nonlactating, female volunteers, 
aged 18 through 45, inclusive are randomized 4:1 to receive inhaled RDV or placebo-to-match
(PTM). Participants received single doses of 12.5 mg, 31 mg, and 62 mg of Remdesivir for 
Injection formulation via nebulization in Cohorts 1, 2, and 4 respectively or multiple doses of 
31 mg or 62 mg each day for 5 days in Cohorts 3 and 5. Cohorts 1 through 5 received 
Remdesivir for Injection formulation via nebulization, and Cohort 6 received Remdesivir for 
Inhalation Solution formulation. Safety data as of 10 September 2020 included all participants in 
Cohorts 1 through 5. All AEs were mild or moderate. There were no deaths, serious adverse 
events (SAEs), pregnancies, or study drug discontinuations.
Preliminary plasma PK data in healthy participants are available following administration of 
inhaled Remdesivir for Injection formulation as single nominal doses of 12.5 mg to 62 mg (2 mg 
to 10 mg deposited), and as multiple nominal doses of 31 mg (5 mg deposited) and 62 mg 
(10 mg deposited) for 5 days. Following single nominal dose administration of 12.5 mg, 31 mg,
and 62 mg inhaled Remdesivir for Injection formulation, maximal concentrations of RDV and 
GS-704277 were achieved at the end of nebulization or within 30 minutes after the end of 
nebulization; plasma concentrations declined rapidly thereafter and were undetectable (below the 
limit of quantitation) at 2 hours and 4 hours postdose for RDV and GS-704277, respectively. 
GS-441524 concentrations peaked at 3 to 4 hours postdose and remained detectable up to 
48 hours postdose in most participants. Approximately dose proportional increases in the 
exposures of RDV and the metabolites were observed following 12.5 mg, 31 mg and 62 mg 
single dose administration. Following multiple dose administration, no accumulation was noted 
for RDV and GS-704277, consistent with the short half-lives. Accumulation ratios of GS-441524 
ranging from 1.2 to 1.6 were observed on Day 5 consistent with its longer half-life ranging from 
11.2 hours (31 mg single dose) to 28.6 hours (62 mg multiple doses, Day 5).
Overall, the observed steady-state plasma exposures at the 31 mg and 62 mg nominal dose were 
substantially below those observed with the 100 mg IV clinical dose at steady-state (IV 
exposures were approximately 101 and 70-fold higher for RDV, 11 and 6.5-fold higher for 
GS-704277, and 16 and 8.5-fold higher for GS-441524 compared with the 31 mg, and 62 mg
nominal dose of inhaled Remdesivir for Injection formulation, respectively). These results were 
similar to those observed in the nonclinical inhaled Remdesivir for Injection formulation study in 
African green monkeys. Comparison of the preliminary human and nonclinical African green 
monkey PK data indicate that it is reasonable to expect that the 31 mg and 62 mg human nominal 
inhaled doses (5 mg and 10 mg deposited) may produce similar, or exceeding GS-443902 
(triphosphate) levels in respiratory tissues as the 100 mg human IV dose.

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1.2.3.
Rationale for This Study
The evaluation of inhaled RDV as a treatment for COVID-19 is supported by clinical data from 
studies of IV RDV in patients with COVID-19, inhaled administration of RDV in healthy 
volunteers, and nonclinical characterization of inhaled administration in PK, toxicology, and 
efficacy studies.
Remdesivir for treatment of COVID-19 administered by IV infusion is now approved in Japan, 
the EU, US, and numerous countries globally. Emerging data suggest that upper airway disease 
precedes lower airway and lung disease in individuals infected with SARS-CoV-2 {Wolfel 
2020}. Delivery of RDV by inhalation could enable antiviral activity in the respiratory tract 
while achieving lower systemic drug exposures, potentially offering an option in 
non-hospitalized patients, and enabling use of RDV in patients who are not currently eligible for 
IV administration of RDV. Inhalation is a less invasive route of administration which will 
support outpatient administration. Furthermore, drug supply may be more efficiently utilized as 
there is potentially less total active pharmaceutical ingredient needed for each dose by inhalation 
versus IV administration. The current lyophilized clinical formulation of IV RDV, Remdesivir
for Injection, 100 mg, is suitable for nebulization. Additionally, a new formulation with a 
reduced content of sulfobutylether β-cyclodextrin sodium (SBECD), Remdesivir for Inhalation 
Solution, 40 mg, is being evaluated in a Phase 1a study. 
Data from nonclinical studies evaluating inhalation of RDV indicate minimal respiratory tract 
findings in a single dose PK study in African green monkeys, and a 7-day rat repeat-dose toxicity 
study. These studies demonstrate the localized delivery of RDV and formation of the active 
triphosphate, GS-443902, in respiratory tissues with lower systemic exposure to RDV and 
metabolites.
This study will evaluate the potential for a short course of nebulized RDV to prevent progression 
of COVID-19 in participants with early infection. The doses selected are anticipated to result in 
similar levels of triphosphate in the lung as that which results from IV administration.
Remdesivir by IV administration has a favorable safety and efficacy profile. Enrollment of this 
study in multiple parts will allow an initial assessment of safety and antiviral kinetics of 
nebulized RDV in early stage COVID-19 patients in Parts A and B of the study. Part C of the 
study will allow for evaluation of safety and efficacy of an inhaled RDV formulation with 
reduced SBECD content (Remdesivir for Inhalation Solution formulation via a mouthpiece). The 
use of a mouthpiece allows more drug to be administered over a shorter time period compared to 
a facemask and is more suitable for self/at-home administration.

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1.3.
Rationale for the Dose Selection
Remdesivir has been approved for the treatment of COVID-19 in Japan, the EU, and the US at 
an initial dose of 200 mg IV followed by 100 mg IV for the next 4 or 9 days. This protocol 
proposes investigation of a new route of administration through the respiratory tract to deliver 
drug directly to the primary site of infection while reducing overall systemic exposure.
Safety, tolerability, and PK of RDV administered via inhalation are being evaluated in an 
ongoing Phase 1a study in healthy participants (GS-US-553-9018). Two different RDV 
formulations, Remdesivir for Injection formulation and Remdesivir for Inhalation Solution 
formulation, were evaluated in this study at the nominal doses up to 62 mg (estimated 10 mg 
deposited dose, administered using LC® Sprint (PARI Respiratory Equipment, Inc.) equipped 
with sealed facemask and an exhaust filter, 16.1% to 17% device efficiency) once daily for 
5 days. Safety and preliminary PK data are available for the Remdesivir for Injection 
formulation, and PK and safety results for Remdesivir for Inhalation Solution formulation are 
forthcoming. An amendment to protocol GS-US-553-9018 is ongoing to generate additional 
safety and PK data for LC Sprint equipped with mouthpiece, and Remdesivir for Inhalation 
Solution formulation. This additional cohort is planned to run in parallel to Part C of the 
GS-US-553-9020 study, and together will inform on the Phase 3 dose selection for inhaled RDV. 
Both formulations were well tolerated in the healthy volunteer study up to 62 mg nominal dose 
(10 mg deposited). Preliminary data are discussed in Section 1.2.2.1. 
Based on these results, 31 mg and 62 mg doses are proposed for evaluation in Parts A and B of 
the current study, respectively. Briefly, a nominal dose of 31 mg Remdesivir for Injection 
formulation (estimated 5 mg deposited dose; utilizing 16.1% device efficiency) for 3 or 5 days is 
proposed for evaluation in Part A. This dose is predicted to achieve similar concentrations of the 
active GS-443902 in respiratory tissues as those expected following a 100 mg human IV dose. A 
higher nominal dose of 62 mg (estimated 10 mg deposited dose; utilizing 16.1% device 
efficiency), which may provide increased efficacy when administered to patients, is proposed for 
Part B. In both Parts, RDV will be administered using LC Sprint equipped with sealed facemask 
and an exhaust filter. 
Part C: 
Remdesivir for Inhalation Solution formulation and a new device configuration of LC Sprint 
utilizing a mouthpiece for drug delivery will be evaluated in Part C. This new formulation 
contains reduced levels of an excipient, SBECD (7.5% after reconstitution, as compared to 15% 
for Remdesivir for Injection formulation), which may offer improved safety when RDV is 
administered via inhalation. Both the new formulation and the new device configuration are 
being evaluated in healthy participants: Cohort 6 (60 mg Remdesivir for Inhalation Solution 
formulation or placebo, for 5 days, inhaled via sealed facemask) and Cohort 7 (39 mg 
Remdesivir for Inhalation Solution formulation or placebo, single dose, inhaled via mouthpiece). 
In alignment with the doses evaluated in the healthy volunteers study, the nominal dose in Part C 
is projected to be 39 mg (estimated 10 mg deposited dose; utilizing 25.6% mouthpiece 
configuration efficiency).

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The proposed doses for evaluation in Part A, B, and C are anticipated to be safe and efficacious, 
based on the cumulative clinical and nonclinical information available to date (Section 1.2.2.1
and inhalation IB). Estimated dose margins based on mg/g lung weight at the lowest and highest 
nominal doses evaluated in this study are 5.2- and 2.6-fold, respectively (inhalation IB).
Duration of 3 to 5 days of dosing will be evaluated in this study. The 5-day dosing duration is the 
recommended IV remdesivir duration for treatment of COVID-19 requiring hospitalization and 
not requiring invasive mechanical ventilation and/or extracorporeal membrane oxygenation
{VEKLURY 2020}. Shorter treatment duration of IV RDV for 3 days is currently being 
evaluated in an outpatient study (GS-US-540-9012) in COVID-19 patients at risk for disease 
progression.
1.4.
Risk/Benefit Assessment for the Study
Potential risks of a participant’s study involvement include unknown adverse events (AEs) due 
to inhaled RDV. Strategies to mitigate these risks include close monitoring of participant’s
clinical status and laboratory testing. Parameters for discontinuation of the study treatment due to 
AEs will be well defined and closely followed.
Transient, Grade ≤2, treatment-emergent elevations in alanine aminotransferase (ALT) and 
aspartate aminotransferase (AST) were observed with daily IV RDV administration in Phase 1 
studies in healthy volunteers. Transaminases increased is a listed adverse drug reaction to RDV. 
However, due to the reduced systemic exposure to RDV compared to the IV regimen, it is 
anticipated that there will be a lower effect on ALT and AST. Nonetheless, liver function testing 
will be closely monitored during the study.
Remdesivir contains SBECD, an approved excipient. In nonclinical species, SBECD 
administration has been associated with kidney vacuolation and hypertrophy. However, 
nonclinical inhalation toxicology studies and available inhaled clinical data with SBECD support 
its use in the RDV clinical formulation.
Participants may or may not clinically benefit from participation in the study. If efficacious, 
benefits might include shorter duration or lower severity of COVID-19 symptoms or reduced 
progression to severe disease. They may also benefit from increased observations and 
evaluations by health care professionals. Data from this study may support further evaluation of 
inhaled RDV in patients with COVID-19.
During a pandemic, additional potential risks to participants may include adequate study 
treatment availability, interruptions to the study visit schedule, and adherence to 
protocol-specified safety monitoring or laboratory assessments. Refer to Appendix 2 for further 
details on the risks and risk mitigation strategy.
Considering the above, the benefit-risk balance for this study is considered positive.

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1.5.
Compliance
This study will be conducted in compliance with this protocol, Good Clinical Practice (GCP), 
and all applicable regulatory requirements.

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2. 
OBJECTIVES 
The primary objective of this study is: 
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• 
To characterize the impact of inhaled RDV on SARS-CoV-2 viral load in participants with 
early stage COVID-19 
The secondary objectives of this study are: 
• 
To evaluate the safety and tolerability of inhaled Remdesivir for Injection fonnulation in 
participants with early stage COVID-19 
• 
To evaluate the PK of inhaled Remdesivir for Injection fonnulation and its metabolites in 
participants with early stage COVID-19 in Parts A and B 
• 
To characterize and evaluate disease progression from baseline 
• 
To characterize the efficacy, safety, and tolerability of Remdesivir for Inhalation Solution 
fonnulation administered with a mouthpiece in Part C of the study 
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3. 
STUDY DESIGN 
3.1. 
Endpoints 
The primary endpoint of this study is: 
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• 
Time weighted average change in SARS-CoV-2 viral load which is defined as AUC of viral 
load change divided by time between baseline through Day 7 
The secondary endpoints of this study are: 
• 
Proportion of participants with treatment-emergent AEs (TEAEs) and laboratory 
abnonnali ties 
• 
Proportion of participants with TEAEs leading to study treatment discontinuation 
• 
Composite of all-cause medically attended visits (MA Vs) (medical visits attended in person 
by the participant and a health care professional) or death by Day 28 
• 
Composite of COVID-19 related MA Vs (medical visits attended in person by the participant 
and a health care professional) or death by Day 28 
• 
Proportion of participants hospitalized by Day 28 
• 
Characterization of the plasma concentrations of inhaled RDV and its metabolites including 
AUCo 24h, AUC1as1, CLss!F, t112, V vF, Cmax, Tmax, C1as1, T1as1, AUC1au, ')....L., and C1au (Parts A and B 
only) 
• 
Change in SARS-CoV-2 viral load from baseline to Day 5 
• 
Change in SARS-CoV-2 viral load from baseline to Day 7 
• 
Change in SARS-CoV-2 viral load from baseline to Day 14 (Parts A and B only) 
• 
Time to negative SARS-CoV-2 polymerase chain reaction (PCR) 
• 
Time to alleviation (mild or absent) of baseline COVID-19 symptoms as reported on the 
COVID-19 adapted InFLUenza Patient-Reported Outcome (FLU-PRO~ questionnaire 
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3.2. 
Study Design 
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This study is a randomized, blinded, placebo-controlled, multicenter study of inhaled RDV in 
participants with early stage COVID-19 infection. In Parts A and B of the study, eligible 
participants will be randomized in equal proportions to 1 of 3 treatment groups. 
Part C of this study is a randomized, blinded, placebo-controlled, multicenter study of 
Remdesivir for Inhalation Solution fonnulation in participants with early stage COVID-19 
infection. Eligible participants will be randomized in a 3: 1 ratio to 1 of 2 treatment groups to 
receive Remdesivir for Inhalation Solution fonnulation or PTM administered by mouthpiece. 
The tenn "inhaled remdesivir" refers to both the Remdesivir for Injection fonnulation and 
Remdesivir for Inhalation Solution fonnulation when administered via nebulization using the LC 
Sprint. 
3.3. 
Study Treatments 
The study will feature multiple parts: Part A, Part B, and Part C. The pla1med nominal doses are 
provided below by treatment group. 
In Part A, approximately 36 participants who meet all eligibility criteria will be randomized in a 
1: 1: 1 ratio into one of the following 3 treatment groups: 
Treatment Group 1: 31 mg inhaled Remdesivir for Injection fonnulation daily for 5 days 
Treatment Group 2: 31 mg inhaled Remdesivir for Injection fonnulation daily for 3 days 
followed by PTM daily for 2 days 
Treatment Group 3: PTM daily for 5 days 
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Part A
In Part B, if supported by Phase 1a data in healthy volunteers, an additional 36 participants who 
meet all eligibility criteria may be randomized in a 1:1:1 ratio into one of the following treatment 
groups:
Treatment Group 4: 62 mg inhaled Remdesivir for Injection formulation daily for up to 5 days
Treatment Group 5: 62 mg inhaled Remdesivir for Injection formulation daily for up to 3 days 
followed by PTM through Day 5
Treatment Group 6: PTM daily for 5 days
Part B
In Parts A and B, at in-clinic screening, after the participant has provided informed consent, 
assessments will include but are not limited to the following: demographic and baseline 
characteristics, medical history, and concomitant medications will be documented. Body weight 
and height will be measured. A urine pregnancy test will be performed for women of 
childbearing potential. Vital signs including heart rate, temperature, blood pressure, and SpO2
will be recorded. A complete physical examination will be performed.
Participants with PCR-confirmed COVID-19 who enroll in the study will return to clinic daily on 
Days 1 through 5 for study treatment administration and clinical assessments. Participants will 
return to clinic on Days 7 and 14 for follow-up clinical assessment and undergo a Day 28 
follow-up which may be completed by telephone.
n = 36 
Randomized 
1: 1: 1 
n = 36 
Randomized 
1:1:1 
n = 12 
I 
n = 12 
I 
n = 12 
I 
n = 12 
I 
n = 12 
I 
n = 12 
I 
Inhaled Remdesivir for Injection formulation daily 
for 5 days, 31 mg nominal dose 
Inhaled Remdesivir for Injection formulation daily 
for 3 days, 31 mg nominal dose 
PTM daily for 5 days 
Inhaled Remdesivir for Injection formulation daily 
for up to 5 days, 62 mg nominal dose 
Inhaled Remdesivir for Injection formulation daily 
for up to 3 days, 62 mg nominal dose 
PTM daily for 5 days 

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Part C
Part C of the study will include an expanded safety and efficacy assessment of an additional 
80 participants. Participants in Part C will be enrolled after review of preliminary safety data 
from Parts A and B through at least Day 7. Approximately 80 participants will be randomized 
3:1 to 1 of 2 treatment groups:
Treatment Group 7: 39 mg Remdesivir for Inhalation Solution formulation once daily for 
5 days by mouthpiece
Treatment Group 8: PTM daily for 5 days by mouthpiece
At screening, after the participant has provided informed consent, assessments will include but 
are not limited to the following: demographic and baseline characteristics, medical history, and 
concomitant medications will be documented. Body weight and height will be measured. A urine 
pregnancy test will be performed for women of childbearing potential. Vital signs including heart 
rate, temperature, blood pressure, and SpO2 will be recorded. A complete physical examination 
will be performed.
In Part C, participants with nucleic acid testing or direct antigen testing-confirmed COVID-19 
who enroll in the study will be administered Remdesivir for Inhalation Solution formulation or 
PTM on Days 1 through 5. Clinical assessments may be conducted at home with the assistance 
of home nursing on Days 1, 3, 5, and 7. Participants will undergo Days 14 and 28 telephone 
contact follow-ups.
3.4.
Safety Review Team
A safety review team (SRT) will be established to assess safety and make decisions on dose 
selection and duration before initiating Part C.
The SRT will include the Gilead medical monitor. Other members of the SRT may include 
representatives from Global Patient Safety (GLPS) (formerly known as Pharmacovigilance and 
Epidemiology [PVE]), Clinical Operations, Biostatistics, and/or Clinical Pharmacology. 
Additional members may be invited to participate if additional expertise is needed. The medical 
monitor serves as the chair of the SRT. An SRT charter (or similar document) will be agreed 
upon by all SRT members prior to the first SRT meeting.
n = 80 
Randomized 
3:1 
n = 60 
n = 20 
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Remdesivir for Inhalation Solution formulation daily 
for 5 days by mouthpiece, 39 mg nominal dose 
PTM daily for 5 days by mouthpiece 

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The data reviewed at the SRT meetings to make optimal dosing and duration decisions will be 
defined in the SRT charter, including safety and nonclinical toxicity data. The quality control 
checks performed on the data reviewed and used for making optimal dosing and duration
decisions will also be described in the SRT charter.
Source data verification may not be performed prior to the meetings. Alternative data quality 
control checks that are performed on data used to make optimal dosing and duration decisions 
are described in the SRT charter.
3.5.
Duration of Treatment
In Parts A and B, participants will receive study treatment with inhaled Remdesivir for Injection 
formulation or PTM for 5 days. The duration of nebulization for Remdesivir for Injection is 
approximately 17 minutes for a nominal dose of 31 mg Remdesivir for Injection formulation
RDV and approximately 34 minutes for a nominal dose of 62 mg inhaled Remdesivir for 
Injection formulation.
In Part C, participants will receive study treatment with Remdesivir for Inhalation Solution or 
PTM for 5 days via a mouthpiece. The duration of nebulization for Remdesivir for Inhalation 
Solution is approximately 19 minutes for a nominal dose of 39 mg Remdesivir for Inhalation 
Solution formulation through a mouthpiece.
3.6.
Discontinuation Criteria
Study treatment dosing in an individual subject will be placed on hold and may be discontinued 
following a review of all available clinical data by the medical monitor and discussion with the 
investigator, if any of the following occurs:

Any SAE or ≥ Grade 3 AE suspected to be related to RDV

Any elevations in ALT ≥5 upper limit of normal (ULN); or ALT ≥3 ULN and total 
bilirubin ≥2 ULN, confirmed by immediate repeat testing

FEV1 decline of > 15% at 30 minutes postdose compared with same day predose FEV1
Discontinuation of study medication is not a seriousness criterion.
Subjects, who discontinue the study medication, should be encouraged to remain in the study and 
attend study visits as described in Section 6 (Study Procedures).
3.7.
End of Study
The end of this study will be the last subject’s last observation (or visit).
3.8.
Poststudy Care
The long-term care of the participant will remain the responsibility of their primary treating 
physician. Remdesivir is being supplied with curative intent. There is no provision for poststudy 
availability.

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3.9. 
Source Data 
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The source data for this study will be obtained from electronic data capture (EDC), central 
laboratory, local laboratory, and specialty laboratory (for PK data). 
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4.
SUBJECT POPULATION
4.1.
Number of Subjects and Subject Selection
In Part A and Part B, approximately 36 participants will be enrolled in each part. Approximately 
80 participants will be enrolled in Part C. Participants in Part C may receive study treatment in a 
home setting.
4.1.1.
Subject Replacement
Subjects who discontinue prior to the end of study will not be replaced.
4.2.
Inclusion Criteria
Subjects must meet all of the following inclusion criteria to be eligible for participation in this 
study:
1) Willing and able to provide written informed consent, or with a legal representative who can 
provide informed consent
2) Aged ≥ 18 years
3) SARS-CoV-2 infection first confirmed by PCR (Parts A and B) or by nucleic acid testing or 
direct antigen testing (Part C) with sample collected ≤ 4 days prior to randomization
4) COVID-19 symptom onset ≤ 7 days prior to randomization
5) SpO2 > 94% on room air
6) Participants of childbearing potential who engage in heterosexual intercourse must agree to 
use protocol specified method(s) of contraception as described in Appendix 5
4.3.
Exclusion Criteria
Subjects who meet any of the following exclusion criteria are not to be enrolled in this study:
1) Ongoing or prior participation in any other clinical trial of an experimental vaccine or 
treatment for COVID-19
2) Prior or current hospitalization for COVID-19 or need for hospitalization

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3) Treatment of COVID-19 with other agents with actual or possible direct antiviral activity 
against SARS-CoV-2 including IV RDV or administration of any SARS-CoV-2 (or 
COVID-19) vaccine
a) Patients chronically administered chloroquine or hydroxychloroquine for any reason are 
to be excluded 
4) Requiring oxygen supplementation
5) Positive pregnancy test (Appendix 5)
6) Breastfeeding female
7) Known hypersensitivity to the study treatment, its metabolites, or formulation excipient
8) Pre-existing pulmonary conditions such as chronic obstructive pulmonary disease or asthma 
(Parts A and B only)

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5.
INVESTIGATIONAL MEDICINAL PRODUCTS
5.1.
Randomization, Blinding, and Treatment Codes Access
5.1.1.
Randomization
In Part A, approximately 36 participants who meet eligibility criteria will be randomized in a 
1:1:1 ratio to receive either of two inhaled 31 mg RDV regimens or PTM starting on Day 1 using 
an interactive voice/web response system (IXRS) and assigned a subject number. In Part B, an 
additional 36 participants who meet eligibility criteria will be randomized in a 1:1:1 ratio to 
receive either of two inhaled 62 mg RDV regimens or PTM starting on Day 1 using an IXRS and 
assigned a subject number.
In Part C, approximately 80 participants will be randomized 3:1 to 1 of 2 treatment groups to 
receive either: Remdesivir for Inhalation Solution formulation (nominal dose of 39 mg to 
achieve 10 mg deposited dose) administered by mouthpiece or PTM administered by mouthpiece
starting on Day 1 using an IXRS and assigned a subject number.
5.1.2.
Blinding
The study will be sponsor unblinded. During the randomized phase, Gilead personnel and site 
pharmacist will be unblinded while the investigational site(s) and subjects participating in the 
study will remain blinded. To mitigate the risks of inadvertently releasing the treatment 
information, certain Gilead staff will only be provided with the unblinded information when 
there is a need to access such information for data analysis to support internal dose 
determination. Should Gilead staff receive unblinding information, they will maintain the 
confidentiality of the unblinded information, and will not communicate the information to 
blinded sites, or subjects as specified in Gilead standard operating procedures (SOPs).
During the randomized phase, subjects and all study site personnel directly involved in the 
conduct of the study will be blinded to treatment assignment. Specified personnel may be 
unblinded based on their study role. Study treatment will be dispensed by an unblinded
pharmacist to the subjects. Monitors, who will oversee activities relating to study drug, such as 
drug storage, drug accountability, and verifying randomization schedules as documented in the 
Study Monitoring Plan, will remain unblinded. Other non-Gilead personnel who are responsible 
for ensuring data integrity or participant safety may be unblinded as well. The Pharmacokinetics 
File Administrator, or designee, in Bioanalytical Operations and/or Clinical Data Management,
who facilitates the data transfer of PK files between Gilead and vendors, will remain unblinded. 
Individuals in Clinical Packaging & Labeling or Clinical Supply Management who have an 
Unblinded Inventory Manager role in the IXRS system for purposes of study treatment inventory 
management will remain unblinded. Individuals in Clinical Virology responsible for the selection 
of samples for sequencing and/or interpretation of sequencing data will remain unblinded. 
Individuals in GLPS responsible for safety signal detection, IND safety reporting and/or 
expedited reporting of suspected unexpected serious adverse reactions (SUSARs) may be 
unblinded to individual case data and/or group level summaries. External (ie, contract research 
organizations) Biostatisticians and Programmers may be unblinded for data monitoring purposes.

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Regulatory Quality and Compliance personnel in Research and Development may also be 
unblinded for purposes of supporting Quality Assurance activities and/or Regulatory Agency 
inspections.
5.1.3.
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 for that subject. 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 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 study 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.
5.2.
Description and Handling of Remdesivir
5.2.1.
Formulation
Remdesivir for Injection, 100 mg, is a preservative-free, white to off-white or yellow, 
lyophilized solid containing 100 mg of remdesivir that is to be reconstituted with 19 mL of 
sterile water for injection prior to administration by inhalation through a nebulizer. Following 
reconstitution, each vial contains a 5 mg/mL remdesivir concentrated solution with sufficient 
volume to allow withdrawal of 20 mL (100 mg of remdesivir). Remdesivir for Injection, 100 mg, 
is supplied as a sterile product in a single-use, 30 mL, Type 1 clear glass vial. In addition to the 
active ingredient, Remdesivir for Injection, 100 mg contains the following inactive ingredients: 
SBECD, water for injection, hydrochloric acid, and sodium hydroxide. Hydrochloric acid and 
sodium hydroxide are used to adjust the formulation to a pH of 3.0 to 4.0.
The supplied Placebo-to-Match Remdesivir for Injection, 100 mg, (PTM Remdesivir for 
Injection, 100 mg) is identical in physical appearance to the active formulation and contains the 
same inactive ingredients.
Remdesivir for Inhalation Solution, 40 mg, is a preservative-free, white to off-white or yellow, 
lyophilized solid containing RDV that is to be reconstituted with 8.4 mL of sterile water for 
injection prior to administration by inhalation through a nebulizer. Following reconstitution, each 
vial contains a 5 mg/mL RDV solution with sufficient volume to allow withdrawal of 8 mL 
(40 mg of RDV). Remdesivir for Inhalation Solution, 40 mg, is supplied as a sterile product in a 
single-use, 20 mL, Type I clear glass vial. In addition to the active ingredient, Remdesivir for 
Inhalation Solution, 40 mg, contains the following inactive ingredients: SBECD, water for 

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injection, hydrochloric acid, and sodium hydroxide. Hydrochloric acid and sodium hydroxide are 
used to adjust the formulation to a pH of 3.0 to 4.0.
The supplied Placebo-to-Match Remdesivir for Inhalation Solution, 40 mg, (PTM Remdesivir 
for Inhalation Solution, 40 mg) is identical in physical appearance to the active formulation and 
contains the same inactive ingredients.
Detailed information regarding study treatment administration and reconstitution instructions are 
included in a pharmacy manual provided to the investigator.
5.2.2.
Packaging and Labeling
Remdesivir for Injection, 100 mg, and placebo are provided in 30 mL glass vials enclosed with 
rubber stopper and aluminum seal with a polypropylene flip-off cap. Following reconstitution, 
each single-use vial contains sufficient volume to allow withdrawal of 20 mL (100 mg RDV or 
placebo).
Remdesivir for Inhalation Solution, 40 mg, and placebo are provided in 20 mL glass vials 
enclosed with rubber stopper and aluminum seal with a polypropylene flip-off cap. Following 
reconstitution, each single-use vial contains sufficient volume to allow withdrawal of 8 mL 
(40 mg RDV or placebo).
Remdesivir for Injection, 100 mg, Remdesivir for Inhalation Solution, 40 mg, and their matching 
placebo vials to be distributed to study centers and shall be labeled to meet applicable 
requirements of the US FDA and/or local regulations.
Sufficient quantities of Remdesivir for Injection, 100 mg, Remdesivir for Inhalation Solution, 
40 mg, and their matching placebo vials will be shipped to the investigator or qualified designee 
from Gilead Sciences Clinical Supplies Management (or its designee).
5.2.3.
Storage and Handling
Remdesivir for Injection, 100 mg, and PTM Remdesivir for Injection, 100 mg, vials should be 
stored below 30 °C prior to use. Remdesivir for Injection and placebo vials are recommended to 
be reconstituted and diluted within the same day as administration. Remdesivir for Injection and 
placebo vials do not contain any preservatives and are intended for single-use. Any unused 
Remdesivir for Injection and placebo material should be discarded.
The total storage time of reconstituted solution containing Remdesivir for Injection or placebo 
should not exceed 4 hours at room temperature (20 °C to 25 °C) or 24 hours at refrigerated 
temperature (2 °C to 8 °C). Any unused Remdesivir for Injection and placebo material should be 
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Remdesivir for Inhalation Solution, 40 mg, and PTM Remdesivir for Inhalation Solution, 40 mg, 
vials should be stored below 30 °C prior to use. Remdesivir for Inhalation Solution and placebo 
vials are recommended to be reconstituted and diluted within the same day as administration, if 
feasible. Remdesivir for Inhalation Solution and placebo vials do not contain any preservatives 
and are intended for single-use. Any unused Remdesivir for Inhalation Solution and placebo 
material should be discarded.
The total storage time of reconstituted solution containing Remdesivir for Inhalation Solution or 
placebo should not exceed 4 hours at room temperature (20 °C to 25 °C) or 7 days at refrigerated 
temperature (2 °C to 8 °C). Any unused Remdesivir for Inhalation Solution and placebo material 
should be discarded.
5.3.
Dosage and Administration of Remdesivir
Remdesivir for Injection, 100 mg, and Remdesivir for Inhalation Solution, 40 mg, will be 
provided by Gilead. Remdesivir for Injection will be administered in Parts A and B of the study 
and Remdesivir for Inhalation Solution will be administered in Part C of the study. 
All study treatments will be administered at approximately the same time each day.
In Parts A and B, RDV or PTM will be administered as an aerosolized solution by inhalation 
through a sealed facemask coupled with a nebulizer with a single inlet/outlet and exhaust filter.
The duration of nebulization is approximately 17 minutes for a nominal dose of 31 mg inhaled 
Remdesivir for Injection. The duration of nebulization is approximately 34 minutes for a nominal 
dose of 62 mg inhaled Remdesivir for Injection.
In Part C, RDV or PTM will be administered as an aerosolized solution by inhalation through a 
mouthpiece coupled with a nebulizer with a single inlet/outlet. The duration of nebulization is 
approximately 19 minutes for a nominal dose of 39 mg Remdesivir for Inhalation Solution.
Detailed information regarding study treatment administration and reconstitution instructions can 
be found in the pharmacy manual.
5.4.
Dispensing, Accountability, and Disposal or Return of Study Treatment
The investigator (or designee, eg, study center pharmacist) will acknowledge receipt of the study 
treatment (after reviewing the shipment’s content and condition) from Gilead (or designee). The 
investigator will maintain an accurate inventory of all study drugs. For Parts A and B, each dose 
of the study treatments administered at the study center will be administered by qualified study 
center staff. The dose of study treatments administered to subjects in the clinic under the 
supervision of staff will be accurately recorded on the Study Drug Accountability form provided 
by Gilead (or on equivalent documentation maintained by the study center), which indicates the 
date and quantity of each dosage formulation dispensed to individual subjects. For Part C, each 
dose of study treatment may be administered at home or in-clinic. During study drug 
dispensation, the dose of study treatment will be accurately recorded on the Study Drug 
Accountability form provided by Gilead (or on equivalent documentation maintained by the 

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study center), which indicates the date and quantity of each dosage formulation dispensed to 
individual subjects. If study drug is administered at the home setting, a home health service 
provider will be available to provide supervision either in-person or via telehealth. All 
information and documentation related to home administration of study drug will be provided to 
the investigator by the home health provider, wherever applicable, in a timely manner.
Gilead recommends that used and unused study treatment should be destroyed at the site. If the 
site has an appropriate SOP for drug destruction as determined by Gilead, the site may destroy 
used (empty or partially empty) and unused study treatment supplies in accordance with that 
site’s approved SOP. A copy of the site’s approved SOP will be obtained for the electronic Trial 
Master File. If study drug is destroyed onsite, the investigator must maintain accurate records for 
all study treatments destroyed. Records must show the identification and quantity of each unit 
destroyed, the method of destruction, and the person who disposed of the study treatment. Upon 
study completion, copies of the study treatment accountability records must be filed at the site. 
Another copy will be returned to Gilead.
If the site does not have an appropriate SOP for drug destruction, used and unused study 
treatment supplies are to be sent to the designated disposal facility for destruction. The study 
monitor will provide instructions for return.
The study monitor will review study treatment supplies and associated records at periodic 
intervals.
For both disposal options listed above, the study monitor must first perform drug accountability 
during a remote monitoring visit.
5.5.
Prior and Concomitant Medications
Due to antagonism observed in vitro with RDV, use of chronically administered chloroquine or 
hydroxychloroquine for any reason is exclusionary. 
Concomitant treatment with other agents with actual or possible direct antiviral activity against
SARS-CoV-2 (including IV RDV) is prohibited.
Medications will be assessed from screening to the Day 28 Follow-up visit.

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6.
STUDY PROCEDURES
The study procedures to be conducted for each subject enrolled in the study are presented in 
tabular form in Appendix 3 and described in the text that follows.
The investigator must document any deviation from the protocol procedures and notify Gilead or 
contract research organization.
6.1.
Subject Enrollment and Treatment Assignment
Entry into screening does not guarantee enrollment into the study. In order to manage the total 
study enrollment, Gilead, at its sole discretion, may suspend screening and/or enrollment at any 
site or study-wide at any time. In Part C of the study, study visits may be performed in-clinic or
at the participant’s home via home health and/or telehealth, virtually or remotely, as permitted by 
local and institutional regulations.
6.2.
Pretreatment Assessments
6.2.1.
Study Parts A, B, and C: Screening Visit
Subjects will be screened in-clinic within 2 days before randomization to determine eligibility 
for participation in the study. The following will be performed and documented at screening:

Obtain written informed consent, or with a legal representative who can provide informed 
consent
After the informed consent the following assessments are performed to determine eligibility 
requirements as specified in the inclusion and exclusion criteria:

Obtain medical history including the following information (eg, date of first symptoms, 
overall symptoms, exposure source, demographics, baseline characteristics), allergies, and 
medical history

Review concomitant medications

Complete physical examination (urogenital/reproductive/anorectal exams will be performed 
only if clinically indicated) including vital signs (heart rate, temperature, blood pressure, and 
SpO2), body weight, and height

Urine pregnancy test (females of childbearing potential only)

Childbearing female participants who are not postmenopausal (see Appendix 5) who do not 
wish to follow protocol-defined contraception will need a serum follicle-stimulating hormone 
(FSH) test (FSH test is required for women who are < 54 years old and have stopped 
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
Documentation of SARS-CoV-2 infection first confirmed by PCR (Parts A and B) or by 
nucleic acid testing or direct antigen testing (Part C) with sample collected ≤4 days prior to 
randomization

Record any SAEs and all AEs related to protocol-mandated procedures occurring after 
signing of the consent form
In Study Parts A and B, study subjects who qualify should be immediately randomized. 
Randomization and dosing should occur on the same day if possible.
From the time of obtaining informed consent through the first administration of study treatment, 
record all SAEs, as well as any AEs related to protocol-mandated procedures on the AEs
electronic case report form (eCRF). All other untoward medical occurrences observed during the 
screening period, including exacerbation or changes in medical history are to be considered 
medical history. See Section 7 Adverse Events and Toxicity Management for additional details.
6.2.2.
Study Parts A and B: Baseline/Day 1 Assessments
The following evaluations are to be completed at the Day 1 visit in-clinic. The investigator must 
have confirmed eligibility before proceeding with randomization. If the screening and Day 1 
visits occur on the same day, no procedures need to be repeated. Participants must complete the 
following assessments before being administered study treatment, unless otherwise stated:

Complete symptom-directed physical examination including vital signs (heart rate, 
temperature, blood pressure, SpO2)

Perform 12-lead electrocardiogram (ECG)

Perform FEV1 (predose and 10 minutes postdose)
Repeat of FEV1 should be performed 30 minutes postdose if there is > 15% reduction in 
FEV1 at 10 minutes postdose compared with the same day predose FEV1. FEV1
assessment may also be performed if there is a clinical concern of bronchospasm

Perform chest x-ray

Complete daily adapted FLU-PRO© questionnaire

Safety laboratory samples will be collected for the following analyses:
Hematology
Coagulation
Chemistry

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• 
Obtain nasopharyngeal and oropharyngeal swabs, and saliva samples for SARS-CoV-2 
quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) testing and possible 
viral resistance testing 
• --na PK assessment: end of nebulization 
I 
I 
• 
Review AEs and concomitant medications 
• 
Inhaled Remdesivir for Injection fonnulation administration: 
6.3. 
Inhaled Remdesivir for Injection fonnulation will be administered to participants at the 
site under close supervision. 
Healthcare professionals administering inhaled Remdesivir for Injection fonnulation 
should have the appropriate medication available for immediate use in case of 
hypersensitivity. The participant should be treated according to the standard of care 
(SOC) for management of hypersensitivity reaction. After dose administration, 
monitoring should be done as follows: 
Approximately 30 minutes post dose administration, participants should be observed, 
and vital signs should be perfonned prior to discharge 
Study Parts A and B: Daily Study Assessments (Days 2-5) 
The following evaluations are to be completed daily and prior to study treatment administration 
from Days 2-5 in-clinic, unless otherwise stated: 
• 
Complete symptom-directed physical examination including vital signs (heart rate, 
temperature, blood pressure, SpO2) 
• 
Complete daily adapted FLU-PRO© questio1maire 
• 
Safety laboratory samples (Days 3 and 5) 
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
Obtain nasopharyngeal, oropharyngeal swabs, and saliva samples for SARS-CoV-2 
RT-qPCR testing and possible viral resistance testing

Perform FEV1 (predose and 10 minutes postdose)
Repeat of FEV1 should be performed 30 minutes postdose if there is > 15% reduction in 
FEV1 at 10 minutes postdose compared with the same day predose FEV1. FEV1
assessment may also be performed if there is a clinical concern of bronchospasm

Sparse plasma PK assessment: predose and end of nebulization (Day 3)

Review AEs and concomitant medications

Inhaled Remdesivir for Injection formulation administration:
Inhaled Remdesivir for Injection formulation will be administered to participants at the 
site under close supervision. Healthcare professionals administering inhaled Remdesivir 
for Injection formulation should have the appropriate medication available for immediate 
use in case of hypersensitivity. The participant should be treated according to the SOC
for management of hypersensitivity reaction. After dose administration, monitoring 
should be done as follows:
Approximately 30 minutes post dose administration, participants should be observed, and 
vital signs should be performed prior to discharge
6.4.
Study Parts A and B: Follow-Up Assessments (Days 7 and 14)
The following evaluations are to be completed on Days 7 and 14 (± 3 days) in-clinic:

Complete symptom-directed physical examination including vital signs (heart rate, 
temperature, blood pressure, SpO2)

Complete daily adapted FLU-PRO© questionnaire

Safety laboratory samples

Obtain nasopharyngeal, oropharyngeal swabs, and saliva samples for SARS-CoV-2 
RT-qPCR testing and possible viral resistance testing

Single PK assessment (Day 7)

Review AEs and concomitant medications
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6.5.
Study Parts A and B: Day 28 Follow-Up Assessment (± 5 days)
The following evaluations are to be completed on Day 28 and may be completed by telephone:

Review AEs and concomitant medications
6.6.
Study Part C: Baseline/Day 1, Days 3, 5, and 7 Assessments
The investigator must have confirmed eligibility before proceeding with randomization. If the 
screening and Day 1 visits occur on the same day, no procedures need to be repeated. Whenever 
possible, Day 1 dosing should occur on the same day as screening. The following evaluations are 
to be completed at Days 1, 3, 5, and 7. They may be completed at home with the assistance of 
home nursing. Participants must complete the following assessments before being administered 
study treatment, unless otherwise stated:

Complete symptom-directed physical examination including vital signs (heart rate, 
temperature, blood pressure, SpO2)

Complete daily adapted FLU-PRO© questionnaire

On Days 1 through 5, perform FEV1 (predose and 10 minutes postdose)
Repeat of FEV1 should be performed 30 minutes postdose if there is > 15% reduction in 
FEV1 at 10 minutes postdose compared with the same day predose FEV1. FEV1
assessment may also be performed if there is a clinical concern of bronchospasm

Obtain nasopharyngeal and oropharyngeal swabs, and saliva samples for SARS-CoV-2 
RT-qPCR testing and possible viral resistance testing

PK assessments
Days 3 and 5: Sparse plasma PK assessment at predose
Day 7: Single anytime plasma PK assessment

Safety laboratory samples (Days 1, 3, 5, and 7)

Review AEs and concomitant medications

Remdesivir for Inhalation Solution formulation administration (Days 1-5):
Remdesivir for Inhalation Solution formulation may be administered at home to 
participants with in-person or telehealth support
For participants with pre-existing pulmonary conditions (ie, chronic obstructive 
pulmonary disease [COPD] or asthma) enrolled in Part C of the study, prescribed inhalers 
may not be used ≤ 30 minutes prior to Remdesivir for Inhalation Solution formulation 
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Healthcare professionals overseeing Remdesivir for Inhalation Solution formulation 
therapy remotely will observe the patient for any signs of adverse event. If any adverse 
event is observed and cannot be managed remotely appropriate urgent care measures will 
be implemented. 
■
Approximately 30 minutes after dose administration, participants should be observed
remotely prior to telehealth support session concluding
6.7.
Study Part C: Days 2 and 4 Assessments
The following evaluations are to be completed daily and prior to study treatment administration 
on Days 2 and 4. They may be completed at home with telehealth support, unless otherwise 
stated:

Complete daily adapted FLU-PRO© questionnaire

Perform FEV1 (predose and 10 minutes postdose)
Repeat of FEV1 should be performed 30 minutes postdose if there is > 15% reduction in 
FEV1 at 10 minutes postdose compared with the same day predose FEV1. FEV1
assessment may also be performed if there is a clinical concern of bronchospasm

Review AEs and concomitant medications

Remdesivir for Inhalation Solution formulation administration:
Remdesivir for Inhalation Solution formulation may be administered at home to 
participants with in-person or telehealth support
For participants with pre-existing pulmonary conditions (ie, COPD or asthma) enrolled in
Part C of the study, prescribed inhalers may not be used ≤30 minutes prior Remdesivir 
for Inhalation Solution formulation administration
Healthcare professionals overseeing Remdesivir for Inhalation Solution formulation 
therapy remotely will observe the patient for any signs of adverse event. If any adverse 
event is observed and cannot be managed remotely appropriate urgent care measures will 
be implemented. 
■
Approximately 30 minutes after dose administration, participants should be observed
remotely prior to telehealth support session concluding
6.8.
Study Part C: Follow-Up Assessments (Days 14 and 28)
The following evaluations are to be completed on Day 14 (± 3 days) and Day 28 (± 5 days) and 
may be completed by telephone:

Complete daily adapted FLU-PRO© questionnaire (Day 14 only)

Review AEs and concomitant medications

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6.9.
Chest X-Ray
In Study Parts A and B, a chest x-ray will be performed at Day 1. If screening visit and Day 1 are 
the same day, chest x-ray does not need to be repeated if completed as SOC < 2 days before 
screening. 
6.10.
FEV1
FEV1 will be performed daily during treatment days and will be performed both predose and 
10 minutes postdose. Repeat FEV1 should be performed at 30 minutes postdose if there is 
> 15% reduction in FEV1 at 10 minutes postdose compared with the same day pre-dose FEV1.
FEV1 assessment may also be performed if there is a clinical concern of bronchospasm.
All subjects with >15% reduction in FEV1 compared with same day predose FEV1 should be
monitored until FEV1 normalizes.
FEV1 assessments will be performed as per the current American Thoracic Society 
Standardization.
6.11.
Clinical Laboratory Assessments
Clinical laboratory assessments will be performed throughout the study as outlined below and in
Appendix 3.
The following clinical laboratory assessments will be performed at screening and analyzed 
locally at sites:

Urine pregnancy test (females of childbearing potential only)

FSH testing (screening only): females who are < 54 years old and have ceased menstruating 
for ≥ 12 months but do not have documentation of ovarian hormonal failure only and do not 
wish to follow protocol-defined contraception
The following clinical laboratory assessments will be performed at the applicable visits and sent 
to a central laboratory for analysis:

Chemistry: alkaline phosphatase, AST, ALT, gamma-glutamyl transferase, total bilirubin, 
direct and indirect bilirubin, total protein, albumin, lactate dehydrogenase, creatine 
phosphokinase, bicarbonate, blood urea nitrogen, calcium, chloride, creatinine, glucose, 
lipase, magnesium, phosphorus, potassium, sodium, uric acid 

Hematology: hematocrit, hemoglobin, platelet count, red blood cell count, white blood cell
count with differential (absolute and percentage), including lymphocytes, monocytes, 
neutrophils, eosinophils, basophils, and mean corpuscular volume

Coagulation panel: prothrombin time, partial thromboplastin time, and international 
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
Virology assessments: nasopharyngeal and oropharyngeal swab samples and saliva samples 
will be used to assess SARS-CoV-2 viral load by RT-qPCR. Once viral load testing is 
complete, the remnant samples may be used to evaluate the emergence of viral resistance by 
SARS-CoV-2 sequencing and/or phenotypic testing

Estimated glomerular filtration rate will be determined according to:
Cockcroft-Gault formula for creatinine clearance for participants ≥ 18 years of age
Creatinine clearance will be estimated based on screening body weight
Men: 
(140 age in years) × (wt in kg)
 creatinine clearance (CLcr) (mL/min)
72 × (serum creatinine in mg/dL)
Women: (140 age in years) × (wt in kg) × 0.85  CLcr (mL/min)
72 × (serum creatinine in mg/dL)
6.12.
Pharmacokinetic Assessments
Sparse plasma PK assessments will be conducted in all participants in Parts A, B, and C. In 
Study Parts A and B, sparse plasma PK samples will be collected at Day 1 (end of nebulization, 
) and Day 3 (predose and end of nebulization). In 
Study Part C, sparse plasma PK samples will be collected at Days 3 and 5 (predose) and a single 
anytime PK sample will be collected on Day 7.
Up to 6 participants/group in Part A and Part B will have intensive PK assessments. Intensive PK
samples will be collected at Day 1 and an additional collection, either at Day 3 or Day 5, at the 
following time points relative to the end of nebulization: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 
and 24 hours post end of nebulization. An additional single PK sample will be collected on 
Day 7 visit for subjects who participate in the intensive PK assessments.
6.13.
Assessments for Early Discontinuation from Study
If a participant discontinues study dosing (for example, as a result of an AE), every attempt 
should be made to keep the participant in the study and continue to perform the required 
study-related follow-up and procedures (see Section 6.13.1, Criteria for Discontinuation of Study 
Treatment). If this is not possible or acceptable to the participant or investigator, the participant 
may be withdrawn from the study.
6.13.1.
Criteria for Discontinuation of Study Treatment
Study treatment 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 if supported by both investigator and Gilead medical monitor
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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 
• 
Lack of efficacy 
• 
Subject request to discontinue for any reason 
• 
Subject noncompliance 
• 
Pregnancy during the study; refer to Appendix 5 
• 
Discontinuation of the study at the request of Gilead, a regulatory agency, or an institutional 
review board (IRB) or independent ethics c01mnittee (IEC) 
• 
Any SAE or~ Grade 3 AE suspected to be related to RDY 
• 
FEY I decline of > 15% at 30 minutes postdose compared with same day predose FEY 1 
• 
Meeting toxicity management criteria necessitating discontinuation, refer to Section 7.7. 
6.14. 
End of Study 
The end of the study will occur at the last participant's last observation ( or visit). 
6.15. 
Poststudy Care 
The long-tenn care of the participant will remain the responsibility of their primary treating 
physician. Remdesivir is being supplied with curative intent. There is no provision for poststudy 
availability. 
6.16. 
Sample Storage 
The stored biological samples may be used by Gilead or its research partner for future testing to 
provide additional data to answer questions that relate to the main study. At the end of this study, 
these samples may be retained in storage by Gilead for a period up to 15 years. If subjects 
provide additional specific consent, residual PK samples may be destroyed no later than 15 years 
after the end of the study or per country requirements. 
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7.
ADVERSE EVENTS AND TOXICITY MANAGEMENT
7.1.
Definitions of Adverse Events and Serious Adverse Events
7.1.1.
Adverse Events
An AE is any untoward medical occurrence in a clinical study subject administered a study 
treatment, 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 study treatment, whether or not the AE is considered related to the study 
treatment. Adverse events may also include pretreatment or posttreatment complications that 
occur as a result of protocol-specified procedures or special situations (Section 7.1.3).
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 AE and must be reported

Preexisting 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 (Section 7.1.3)

Any medical condition or clinically significant laboratory abnormality with an onset date 
before the informed consent form (ICF) is signed and not related to a protocol-associated 
procedure is not an AE but rather considered to be preexisting and should be documented as 
medical history.
Preexisting events that increase in severity or change in nature after study treatment initiation or 
during or as a consequence of participation in the clinical study will also be considered AEs.
7.1.2.
Serious Adverse Events
An SAE is defined as an event that, at any dose, results in the following:

Death

A life-threatening situation (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

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
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.
7.1.3.
Study Treatments and Gilead Concomitant Therapy Special Situations 
Reports
Special situation reports (SSRs) include all reports of medication error, abuse, misuse, overdose, 
occupational exposure, drug interactions, exposure via breastfeeding, unexpected benefit, 
transmission of infectious agents via the product, counterfeit of falsified medicine, and 
pregnancy regardless of an associated AE.
Medication error is any unintentional error in the prescribing, dispensing, preparation for 
administration or administration of a study treatment while the medication is in the control of a
health care professional, patient, or consumer. Medication errors may be classified as a 
medication error without an AE, which includes situations of missed dose, medication error with 
an AE, intercepted medication error, or potential medication error.
Abuse is defined as persistent or sporadic intentional excessive use of a study treatment by a 
subject.
Misuse is defined as any intentional and inappropriate use of a study treatment 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 study 
treatment given per administration or cumulatively which is above the maximum recommended 
dose as per protocol or in the product labeling (as it applies to the daily dose of the subject in 
question). In cases of a discrepancy in drug accountability, overdose will be established only 
when it is clear that the subject has taken the excess dose(s). Overdose cannot be established 
when the subject cannot account for the discrepancy, except in cases in which the investigator 
has reason to suspect that the subject has taken the additional dose(s).
Occupational exposure is defined as exposure to a study treatment as a result of one’s 
professional or nonprofessional occupation.
Drug interaction is defined as any drug/drug, drug/food, or drug/device interaction.

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Unexpected benefit is defined as an unintended therapeutic effect where the results are judged to 
be desirable and beneficial.
Transmission of infectious agents is defined as any suspected transmission of an infected agent 
through a Gilead study treatment.
Counterfeit or falsified medicine: Any study treatment with a false representation of (a) its 
identity, (b) its source, or (c) its history.
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 Treatments and Procedures
The investigator or qualified subinvestigator is responsible for assessing the relationship to study 
treatment using clinical judgment and the following considerations:

No: Evidence exists that the AE has an etiology other than the study treatment. For SAEs, an 
alternative causality must be provided (eg, preexisting condition, underlying disease, 
intercurrent illness, or concomitant medication).

Yes: There is reasonable possibility that the event may have been caused by the study 
treatment.
It should be emphasized that ineffective treatment should not be considered as causally related in 
the context of AE reporting.
The relationship to study procedures (eg, invasive procedures such as venipuncture or biopsy) 
should be assessed using the following considerations:

No: Evidence exists that the AE has an etiology other than the study procedure.

Yes: The AE occurred as a result of protocol procedures (eg, venipuncture).
7.2.2.
Assessment of Severity
The severity of AEs will be graded using the Division of AIDS (DAIDS) Table for Grading the 
Severity of Adult and Pediatric Adverse Events, Version 2.1 dated July 2017. For each episode, 
the highest grade attained should be reported as defined in the grading scale. The DAIDS scale is 
available at the following location:
https://rsc.niaid.nih.gov/sites/default/files/daidsgradingcorrectedv21.pdf

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7.3.
Investigator Requirements and Instructions for Reporting Adverse Events 
and Serious Adverse Events
7.3.1.
Requirements for Collection Prior to Study Treatment Initiation
After informed consent, but prior to initiation of study treatment, the following types of events 
must be reported on the applicable eCRFs: all SAEs and AEs related to protocol-mandated 
procedures.
7.3.2.
Adverse Events
Following initiation of study treatment, collect all AEs, regardless of cause or relationship, 
including the protocol-required posttreatment follow-up period must be reported on the eCRFs as 
instructed.
All AEs and clinically significant laboratory abnormalities should be followed until resolution or 
until the AE is stable, if possible. Gilead may request that certain AEs be followed beyond the 
protocol-defined follow-up period.
7.3.3.
Serious Adverse Events
All SAEs, regardless of cause or relationship, that occur after the subject first consents to 
participate in the study (ie, signing the ICF) and throughout the duration of the study, including 
the posttreatment follow-up visit, must be reported on the applicable eCRFs and Gilead GLPS 
(formerly PVE) as instructed below in this section. This also includes any SAEs resulting from 
protocol-associated procedures performed after the ICF is signed.
Any SAEs and deaths that occur after the posttreatment follow-up visit but within 30 days of the 
last dose of study treatment, 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 the protocol-defined follow-up 
period has concluded and the event is deemed relevant to the use of study treatment, the 
investigator should promptly document and report the event to Gilead GLPS.
Instructions for reporting SAEs are described in Section 7.4.1.
7.3.4.
Study Treatment Special Situations Reports
All study treatment SSRs that occur from study treatment initiation and throughout the duration 
of the study, including the posttreatment follow-up visit, must be reported to Gilead GLPS 
(Section 7.4.2). Adverse events and SAEs resulting from SSRs must be reported in accordance to 
the AE and SAE reporting guidance (Section 7.3).

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7.3.5.
Concomitant Therapy Reports
7.3.5.1.
Gilead Concomitant Therapy Special Situations Report
Special situation reports involving a Gilead concomitant therapy (not considered study 
treatment), 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 posttreatment 
follow-up visit, must be reported to Gilead GLPS utilizing the paper SSR (Section 7.4.2.1).
7.3.5.2.
Non-Gilead Concomitant Therapy Report
Special situations involving non-Gilead concomitant medications does not need to be reported on 
the SSR 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.
All clinical sequelae in relation to these SSRs 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.
7.4.
Reporting Process for Serious Adverse Events and Special Situation Reports
7.4.1.
Serious Adverse Event Reporting Process

For fatal or life-threatening events, copies of hospital case reports, autopsy reports, and other 
documents are also to be transmitted by email or fax when requested and applicable. 
Transmission of such documents should occur without personal subject identification, 
maintaining the traceability of a document to the subject identifiers.

Additional information may be requested to ensure the timely completion of accurate safety 
reports.

Any medications necessary for treatment of the SAE must be recorded onto the concomitant 
medication section of the subject’s eCRF and the SAE narrative section of the Safety Report 
Form eCRF.
7.4.1.1.
Electronic Serious Adverse Event Reporting Process

Site personnel will record all SAE data on the applicable eCRFs and from there transmit the 
SAE information to Gilead GLPS within 24 hours of the investigator’s knowledge of the 
event from ICF signature throughout the duration of the study, including the 
protocol-required posttreatment follow-up period.

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
If it is not possible to record and transmit the SAE information electronically, record the SAE 
on the paper SAE reporting form and transmit within 24 hours:
Gilead GLPS
Gilead GLPS Email: 
 
or
Fax: 

If an SAE has been reported via a paper form because the eCRF database has been locked, no 
further action is necessary. If the database is not locked, any SAE reported via paper must be 
transcribed as soon as possible on the applicable eCRFs and transmitted to GLPS.
7.4.2.
Special Situations Reporting Process
7.4.2.1.
Paper Special Situations Reporting Process for Study Treatment

All SSRs will be recorded on the special situations report form and transmitted by emailing 
or faxing the report form within 24 hours of the investigator’s knowledge of the event to the 
attention of Gilead GLPS from study treatment initiation throughout the duration of the 
study, including the protocol required post treatment follow-up period.
Gilead GLPS 
Gilead GLPS Email
 
or
Fax: 
7.4.2.2.
Reporting Process for Gilead Concomitant Medications

Special situations that involve Gilead concomitant medications that are not considered study 
treatment must be reported within 24 hours of the investigator’s knowledge of the event to 
Gilead GLPS utilizing the paper special situations report form to:
Gilead GLPS
Gilead GLPS Email
 
or
Fax: 

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.

Special situations involving non-Gilead concomitant medications do not need to be reported
on the SSR form; however, special situations that result in AEs due to a non-Gilead 
concomitant medication, must be reported as an AE.
PPD
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7.4.2.3.
Pregnancy Reporting Process

The investigator should report pregnancies in female study subjects and/or female partners of 
male subjects that are identified after initiation of study treatment and throughout the study, 
including the post study treatment follow-up period, to Gilead GLPS using the pregnancy 
report form within 24 hours of becoming aware of the pregnancy. Contact details for 
transmitting the pregnancy report form are as follows:
Gilead GLPS 
Gilead GLPS 
Email: 
 
or
Fax: 

The pregnancy itself is not considered an AE, nor is an induced elective abortion to terminate 
a pregnancy without medical reasons.

All other premature terminations 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, as described in Section 7.4.1. 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 Section 7.4.1. Furthermore, any SAE occurring as an adverse pregnancy outcome post 
study must be reported to the Gilead GLPS.

The subject should receive appropriate monitoring and care until the conclusion of the 
pregnancy. The outcome of the pregnancy/partner pregnancy should be reported to Gilead 
GLPS using the pregnancy outcome report form. If the end of the pregnancy/partner 
pregnancy occurs after the study has been completed, the outcome should be reported 
directly to Gilead GLPS. Gilead GLPS contact information is as follows: 
email
 and fax:
.

Refer to Appendix 5 for Pregnancy Precautions, Definition for Female of Childbearing 
Potential, and Contraceptive Requirements.
7.5.
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 which may be in the form of line listings, serious 
adverse drug reactions, or SUSARs. In accordance with the EU Clinical Trials Directive 
(2001/20/EC), Gilead or a specified designee will notify worldwide regulatory agencies and the 
relevant IEC in concerned Member States of applicable SUSARs as outlined in current 
regulations.
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Assessment of expectedness for SAEs will be determined by Gilead using reference safety 
information specified in the IB or relevant local label as applicable.
All investigators will receive a safety letter notifying them of relevant SUSAR reports associated 
with any study treatment. The investigator should notify the IRB or IEC of SUSAR reports as 
soon as is practical, where this is required by local regulatory agencies, and in accordance with 
the local institutional policy.
7.6.
Clinical Laboratory Abnormalities and Other Abnormal Assessments as 
Adverse Events or Serious Adverse Events
Laboratory abnormalities without clinical significance are not to be recorded as AEs or SAEs. 
However, laboratory abnormalities (eg, clinical chemistry, hematology, urinalysis) that require 
medical or surgical intervention or lead to study treatment 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).
Severity should be recorded and graded according to the DAIDS scale, Version 2.1. For AEs 
associated with laboratory abnormalities, the event should be graded on the basis of the clinical 
severity in the context of the underlying conditions; this may or may not be in agreement with 
the grading of the laboratory abnormality.
All AEs, SAEs, and clinically significant laboratory abnormalities will be followed until 
resolution or until stability of the abnormality is demonstrated.
7.7.
Toxicity Management
Nebulized RDV will be administered to participants under close supervision.
Inhaled Remdesivir for Injection formulation will be administered to participants at the clinical 
site (Parts A and B). Healthcare professionals administering inhaled Remdesivir for Injection 
formulation should have the appropriate medication available for immediate use in case of 
hypersensitivity. The participant should be treated according to the SOC for management of 
hypersensitivity reaction. After dose administration, monitoring should be done as follows:

Approximately 30 minutes after dose administration, participants should be observed, and 
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Remdesivir for Inhalation Solution formulation may be administered to participants in the
participant’s home with in-person or telehealth support (Part C only). Healthcare professionals 
overseeing Remdesivir for Inhalation Solution formulation therapy remotely will observe the 
patient for any signs of adverse event. If any adverse event is observed and cannot be managed 
remotely, appropriate urgent care measures will be implemented. 

Approximately 30 minutes after dose administration, participants should be observed
remotely prior to telehealth support session concluding
For participants with pre-existing pulmonary conditions (ie, COPD or asthma) enrolled in Part C 
of the study, prescribed inhalers may not be used ≤ 30 minutes prior to Remdesivir for Inhalation 
Solution formulation administration.
The participant should be treated according to the SOC for management of hypersensitivity or 
bronchospasm according to site or home health protocol. The medical monitor should be notified 
prior to study treatment discontinuation when medically feasible. Study treatment dosing in an 
individual participant will be placed on hold and may be permanently discontinued, following 
review of all available clinical data by the Medical Monitor and discussion with the investigator, 
in the following conditions:

Development of ALT levels ≥ 5 × ULN

Development of ALT levels ≥ 3 × ULN and bilirubin ≥ 2 × ULN

Acute anaphylactic reaction to RDV

Estimated creatinine clearance < 30 mL/min based on the Cockcroft-Gault formula

Any SAEs and Grade 3 and 4 abnormal laboratory results assessed as related to study 
treatment
For clinical queries, please contact the medical monitor. Study treatment dosing may be resumed 
if it was held due to laboratory abnormality and is now within acceptable range, if the 
abnormality was not attributed to study treatment.
Please refer to Appendix 4 for further details on the management of clinical and laboratory AEs.

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8.1. 
8.1.1. 
STATISTICAL CONSIDERATIONS 
Analysis Objectives and Endpoints 
Analysis Objectives 
The primary objective of this study is: 
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To characterize the impact of inhaled RDV on SARS-CoV-2 viral load in participants with 
early stage COVID-19 
The secondary objectives of this study are: 
• 
To evaluate the safety and tolerability of inhaled Remdesivir for Injection fonn ulation in 
participants with early stage COVID-19 
• 
To evaluate the PK of inhaled Remdesivir for Injection fonnulation and its metabolites in 
participants with early stage COVID-19 in Parts A and B 
• 
To characterize and evaluate disease progression from baseline 
• 
To characterize the efficacy, safety, and tolerability of Remdesivir for Inhalation Solution 
fonnulation administered with a mouthpiece in Part C of the study 
I 
I 
8.1.2. 
Primary Endpoint 
• 
Time-weighted average change in SARS-CoV-2 viral load which is defined as AUC of viral 
load change divided by time between baseline through Day 7 
8.1.3. 
Secondary Endpoint 
The secondary endpoints of this study are: 
• 
Proportion of participants with TEAEs and laboratory abnonnalities 
• 
Proportion of participants with TEAEs leading to study treatment discontinuation 
• 
Composite of all-cause MA Vs (medical visits attended in person by the participant and a 
health care professional) or death by Day 28 
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Composite of COVID-19 related MA Vs (medical visits attended in person by the participant 
and a health care professional) or death by Day 28 
• 
Proportion of participants hospitalized by Day 28 
• 
Characterization of the plasma concentrations of inhaled RDV and its metabolites including 
AUCo 24h, AUC1as1, CLss!F, t112, V vF, Cmax, Tmax, C1as1, T1as1, AUC1au, ')....L., and C1au (Parts A and B 
only) 
• 
Change in SARS-CoV-2 viral load from baseline to Day 5 
• 
Change in SARS-CoV-2 viral load from baseline to Day 7 
• 
Change in SARS-CoV-2 viral load from baseline to Day 14 (Parts A and B only) 
• 
Time to negative SARS-CoV-2 PCR 
• 
Time to alleviation (mild or absent) of baseline COVID-19 symptoms as reported on the 
COVID-19 adapted FLU-PRO© questionnaire 
-
I 
I 
I 
I 
I 
I 
8.2. 
8.2.1. 
Planned Analyses 
Interim Analysis 
Prior to the final analysis, interim analyses may be conducted and the analyses may be submitted 
to regulatory agencies to seek guidance for the overall clinical development program. 
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8.2.2.
Final Analysis
The unblinded final analysis will be performed at the end of study, after all subjects have 
completed the study, outstanding data queries have been resolved or adjudicated as unresolvable, 
and the data have been cleaned and finalized.
8.3.
Analysis Conventions
8.3.1.
Analysis Sets
8.3.1.1.
Efficacy
The primary analysis set for efficacy analysis is defined as the Full Analysis Set, which will 
include all participants who (1) are randomized into the study and (2) have received at least 
1 dose of study treatment. Participants will be grouped according to the treatment to which they 
were randomized.
8.3.1.2.
Safety
The primary analysis set for safety analyses is defined as Safety Analysis Set, which will include 
all participants who (1) are randomized into the study and (2) have received at least 1 dose of 
study treatment. Participants will be grouped according to the treatment which they received.
8.3.1.3.
Pharmacokinetics
Each PK Analysis Set will include all randomized subjects who received at least 1 dose of study 
treatment and had at least 1 nonmissing PK concentration datum reported by the PK laboratory 
for each respective analyte.
8.3.2.
Data Handling Conventions
Natural logarithm transformation for PK parameters will be applied for PK analysis.
For summary statistics, PK concentration values below the limit of quantitation will be treated as 
zero at predose and one-half of the lower limit of quantitation (LLOQ) for postdose time points.
Laboratory data that are continuous in nature but are less than the LLOQ or above the upper limit 
of quantitation, will be imputed to the value of the lower or upper limit plus or minus 
1 significant digit, respectively (e.g., if the result of a continuous laboratory test is < 20, a value 
of 19 will be assigned).
Missing data can have an impact upon the interpretation of the trial data. In general, values for 
missing data will not be imputed. However, a missing pretreatment laboratory result would be 
treated as normal (i.e., no toxicity grade) for the laboratory abnormality summary.
All available data for participants that do not complete the study will be included in data listings.

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8.4.
Demographic and Baseline Characteristics Analysis
Demographic and baseline measurements will be summarized using standard descriptive 
methods.
Demographic summaries will include sex, race/ethnicity, and age.
8.5.
Efficacy Analysis
8.5.1.
Primary Analysis
SARS-CoV-2 viral load will be summarized by treatment using descriptive statistics in Part A 
and Part B. For Part C, time weighted average change in SARS-CoV-2 viral load will be 
compared between the RDV and placebo groups using analysis of covariance with baseline viral 
load included in the model as a covariate.
8.5.2.
Secondary Analyses
The proportion of participants all-cause MAV (medical visits attended in person by the 
participant and a health care professional) or death by Day 28 will be estimated using 
Kaplan-Meier methods by treatment group in Part C. The proportion of participants COVID-19 
related MAVs or death by Day 28 will be estimated using Kaplan-Meier methods by treatment 
group in Part C. The proportion of hospitalization by Day 28 will be summarized by treatment 
group. Kaplan Meier product limit method will be used to estimate time to negative 
SARS-CoV-2 PCR and time to alleviation (mild or absent) of baseline COVID-19 symptoms by 
treatment group.
8.6.
Safety Analysis
All safety data collected on or after the randomization date through Day 28 will be summarized 
by treatment group (according to the study treatment received). Data for the pretreatment will be 
included in data listings.
8.6.1.
Extent of Exposure
A subject’s extent of exposure to study treatment data will be generated from the study treatment
administration data. Exposure data will be summarized by treatment group.
8.6.2.
Adverse Events
Clinical and laboratory AEs will be coded using the Medical Dictionary for Regulatory 
Activities (MedDRA). System organ class, high-level group term, high-level term, preferred 
term (PT), and lower-level term will be attached to the clinical database.
Events will be summarized on the basis of the date of onset for the event. A TEAE will be 
defined as any AE that begins on or after the date of first dose of study treatment up to the date 
of last dose of study treatment plus 30 days.

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Summaries (number and percentage of subjects) of TEAEs (by system organ class and PT) will 
be provided by treatment group.
8.6.3.
Laboratory Evaluations
Selected laboratory data will be summarized using only observed data. Data and change from 
baseline at all scheduled time points will be summarized.
Graded laboratory abnormalities will be defined using the grading scheme in DAIDS Table for 
Grading the Severity of Adult and Pediatric Adverse Events, Version 2.1 dated July 2017.
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 the end date of the study, 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.
Laboratory abnormalities that occur before the first dose of study treatment or after the subject 
has been discontinued from treatment for more than 30 days will be included in a data listing.
8.7.
Adjustments for Multiplicity
No adjustments for multiple comparison are planned.
8.8.
Pharmacokinetic Analysis
For Parts A and B, plasma concentrations and PK parameters (if applicable) for inhaled RDV 
and its metabolites will be listed and summarized using descriptive statistics by treatment group 
(including mean, geometric mean, median, minimum, maximum, and sample size). 
Concentrations of inhaled RDV and its metabolites in plasma over time will be summarized. For 
Part C, plasma concentration of GS-441524 will be listed and summarized using descriptive 
statistics by nominal time.
8.9.
Sample Size
The sample size in this study is determined based on practical considerations and past experience 
with similar types of studies. No sample size/power calculation was performed. A sample size up 
to approximately 152 participants (72 participants for Part A and Part B; 80 participants for 
Part C) should provide a suitable assessment of the descriptive efficacy, and safety profile in this 
population.

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

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Confidentiality 
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The investigator must assure that subjects' anonymity will be strictly maintained and that their 
identities are protected from unauthorized parties. Only an identification code and any other 
unique identifier(s) as allowed by local law (such as year of birth) will be recorded on any fonn 
or biological sample submitted to Gilead, IRB or IEC or laboratory. Laboratory specimens must 
be labeled in such a way as to protect subject identity while allowing the results to be recorded to 
the proper subject. Refer to specific laboratory instructions or in accordance with local 
regulations. NOTE: The investigator must keep a screening log with details for all subjects 
screened and enrolled in the study, in accordance with the site procedures and regulations. 
Subject data will be processed in accordance with all applicable regulations. 
The investigator agrees that all infonnation received from Gilead, including but not limited to the 
IB, this protocol, eCRF, the study treatment, and any other study infonnation, remain the sole 
and exclusive property of Gilead during the conduct of the study and thereafter. This infonnation 
is not to be disclosed to any third party ( except employees or agents directly involved in the 
conduct of the study or as required by law) without prior written consent from Gilead. The 
investigator further agrees to take all reasonable precautions to prevent the disclosure by any 
employee or agent of the study site to any third party or otherwise into the public domain. 
9.1.6. 
Study Files and Retention of Records 
The investigator must maintain adequate and accurate records to enable the conduct of the study 
to be fully docmnented and the study data to be subsequently verified. These docmnents should 
be classified into at least the following 2 categories: (1) investigator's study file, and (2) subject 
clinical source documents. 
The investigator's study file will contain the protocol/amendments, paper or electronic 
completed subject case report fonns (CRFs), IRB or IEC and govenunental approval with 
correspondence, infonned consent, drug records, staff curriculmn vitae and authorization fonns, 
and other appropriate documents and correspondence. 
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The required source data should include sequential notes containing at least the following 
information for each subject:

Subject identification

Documentation that subject meets eligibility criteria, ie, medical history, physical 
examination, and confirmation of diagnosis (to support inclusion and exclusion criteria)

Documentation of the reason(s) a consented subject is not enrolled

Participation in study (including study number)

Study discussed and date of informed consent

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 treatment, including dates of dispensing 
and return

Record of all AEs and other safety parameters (start and end date, and including causality 
and severity), and documentation that adequate medical care has been provided for any AE

Concomitant medication (including start and end date, dose if relevant; dose changes)

Date of study completion and reason for ED, 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, the US, Europe, or Japan) and until there are no pending or planned marketing 
applications in an ICH region; or, if no application is filed or if the application is not approved 
for such indication, until 2 years after the investigation is discontinued and regulatory authorities 
have been notified. Investigators may be required to retain documents longer if specified by 
regulatory requirements, by local regulations, or by an agreement with 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.

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9.1.7.
Case Report Forms
For each subject consented, an eCRF casebook will be completed by an authorized study staff 
member whose training for this function is completed in the EDC system. The eCRF casebook 
will only capture the data required per the protocol schedule of events and procedures. The 
Inclusion/Exclusion Criteria and Enrollment eCRFs should be completed only after all data 
related to eligibility have been received. Data entry should be performed in accordance with the 
CRF Completion Guidelines provided by the Sponsor. Subsequent to data entry, a study monitor 
will perform source data verification (SDV) within the EDC system. System-generated or 
manual queries will be issued in the EDC system as data discrepancies are identified by the 
monitor or Gilead staff, who routinely review the data for completeness, correctness, and 
consistency. The site investigator or site coordinator or other designee 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). Original entries as well as any changes to data fields will be stored in the audit trail of the 
system. At a minimum, prior to any interim time points or database lock (as instructed by 
Gilead), 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. At the 
conclusion of the study, Gilead will provide the site investigator with a read-only archive copy of 
the data entered by that site. This archive must be stored in accordance with the records retention 
requirements outlined in Section 9.1.6.
9.1.8.
Investigator Inspections
The investigator will make available all source documents and other records for this study to 
Gilead’s appointed study monitors, to IRBs/IECs, or to regulatory authority or health authority 
inspectors.
9.1.9.
Protocol Compliance
The investigator is responsible for ensuring the study is conducted in accordance with the 
procedures and evaluations described in this protocol.
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 or IEC 
in accordance with local requirements and receive documented IRB or IEC approval before 
modifications can be implemented.

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9.2.2.
Study Report and Publications
A clinical study report will be prepared and provided to the regulatory agency(ies). 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 9.1.5).
The investigator will comply with Gilead’s request to delete references to its confidential 
information (other than the study results) in any paper or presentation and agrees to withhold 
publication or presentation for an additional 60 days in order to obtain patent protection if 
deemed necessary.
9.3.
Joint Investigator/Sponsor Responsibilities
9.3.1.
Payment Reporting
Investigators and their study staff may be asked to provide services performed under this 
protocol, eg, attendance at Investigator 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 study payments, meal, 
travel expenses or reimbursements, consulting fees, and any other transfer of value.
9.3.2.
Access to Information for Monitoring
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 in 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.

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9.3.3.
Access to Information for Auditing or Inspections
Representatives of regulatory authorities or of Gilead may conduct inspections or audits of the 
clinical study. If the investigator is notified of an inspection by a regulatory authority the 
investigator agrees to notify the Gilead medical monitor immediately. The investigator agrees to 
provide to representatives of a regulatory agency or Gilead access to records, facilities, and 
personnel for the effective conduct of any inspection or audit.
9.3.4.
Study Discontinuation
Both Gilead 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 subjects, 
appropriate regulatory authority(ies), IRBs, or IECs. In terminating the study, Gilead and the 
investigator will assure that adequate consideration is given to the protection of the subjects’ 
interests.

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10.
REFERENCES
Assiri A, Al-Tawfiq JA, Al-Rabeeah AA, Al-Rabiah FA, Al-Hajjar S, Al-Barrak A, et al. 
Epidemiological, Demographic, and Clinical Characteristics of 47 Cases of 
Middle East Respiratory Syndrome Coronavirus Disease From Saudi Arabia: A 
Descriptive Study. Lancet Infect Dis 2013;13 (9):752-61.
Choi WS, Kang CI, Kim Y, Choi JP, Joh JS, Shin HS, et al. Clinical Presentation and Outcomes 
of Middle East Respiratory Syndrome in the Republic of Korea. Infect Chemother 
2016;48 (2):118-26.
de Wit E, van Doremalen N, Falzarano D, Munster VJ. SARS and MERS: Recent Insights Into 
Emerging Coronaviruses. Nature Review 2016;14:523-34.
Ksiazek TG, Erdman D, Goldsmith CS, Zaki SR, Peret T, Emery S, et al. A Novel Coronavirus 
Associated with Severe Acute Respiratory Syndrome. N Engl J Med 2003;348 
(20):1953-66.
Lau SK, Chan JF. Coronaviruses: Emerging and Re-Emerging Pathogens in Humans and 
Animals. Virology journal 2015;12:1-3.
VEKLURY, Gilead Sciences Inc. VEKLURY® (remdesivir) for injection, for intravenous use. 
VEKLURY® (remdesivir) injection, for intravenous use. U.S. Prescribing 
Information. Foster City, CA. Revised October.  2020:
Who Mers-Cov Research Group. State of Knowledge and Data Gaps of Middle East Respiratory 
Syndrome Coronavirus (MERS-CoV) in Humans. PLoS currents 2013;5.
Wolfel R, Corman VM, Guggemos W, Seilmaier M, Zange S, Muller MA, et al. Virological 
Assessment of Hospitalized Patients with COVID-2019 [Abstract] [Accepted]. 
Nature 2020.
Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, et al. A Novel Coronavirus from Patients with 
Pneumonia in China, 2019. N Engl J Med 2020.

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11.
APPENDICES
Appendix 1.
Investigator Signature Page
Appendix 2.
Pandemic Risk Assessment and Mitigation Plan
Appendix 3.
Study Procedures Tables
Appendix 4.
Management of Clinical and Laboratory Adverse Events
Appendix 5.
Pregnancy Precautions, Definition for Female of Childbearing Potential, and 
Contraceptive Requirements

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Appendix 1. 
Investigator Signature Page 
GILEAD SCIENCES, INC. 
333 LAKESIDE DRIVE 
FOSTER CITY, CA 94404 
STUDY ACKNOWLEDGMENT 
FINAL 
Amendment3 
A Phase lb/2a Study in Participants with Early Stage COVID-19 to Evaluate the Safety, 
Efficacy, and Pharmacokinetics of Remdesivir Administered by Inhalation 
GS-US-553-9020, Amendment 3, 13 January 2021 
This protocol bas been approved by Gilead Sciences, Inc. The following signature documents 
this approval. 
PPD 
IPPD 
V 
I 
Date 
INVESTIGATOR STATEMENT 
I have read the protocol, including all appendices, and I agree that it contains all necessary 
details for me and my staff to conduct this study as described. I will conduct this study as 
outlined herein and will make a reasonable effort to complete the study within the time 
designated. 
I will provide all study personuel under my supervision copies of the protocol and access to all 
information provided by Gilead Sciences, Inc. I will discuss this material with them to ensure 
that they are fully informed about the drugs and the study. 
Principal Investigator Name (Printed) 
Signature 
Date 
Site Number 
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Appendix 2.
Pandemic Risk Assessment and Mitigation Plan
During an ongoing pandemic, potential risks associated with subjects being unable to attend 
study visits have been identified for this study.
These risks can be summarized as follows:
1) Study drug supplies to subjects and sites:
a) Subjects may be unable to return to the site for a number of visits to get the study drug, or 
the site may be unable to accept any subject visits. Without study drugs, the subject 
would not be able to stay on the study drug as planned per protocol.
Mitigation plan: Study drug supplies may be provided to the subject from the site without 
a clinic visit, once it is confirmed that the subject may safely continue on study drug as 
determined by the principal investigator (PI). A virtual study visit, via phone or video 
conferencing, must be performed prior to remote study drug resupply. At the earliest 
opportunity, the site will schedule in-person subject visits and return to the protocol’s 
regular schedule of assessments. A qualified courier may be utilized to ship the study 
drug from sites to study subjects if permitted by local ethics committee/institutional 
review boards (IRB)/Regulatory Authority as applicable and with sponsor’s approval.
b) Shipments of study drug could be delayed because of transportation issues. Without study 
drug subject would not be able to stay on the study drug as planned per protocol.
Mitigation plan: The sites’ study drug inventory should be closely monitored. Site staff 
should notify the sponsor or delegate if they foresee shortage in study drug inventory or if 
there is any interruption in local shipping service. The sponsor will continue to monitor 
inventory at the study drug depot and study sites. Manual shipments will be triggered as 
necessary.
2) Subject safety monitoring and follow-up:
a) Subjects may be unable or unwilling to come to the study site for their scheduled study 
visits as required per protocol.
Mitigation plan: For subjects who may be unable or unwilling to visit the study site for 
their scheduled study visits as required per protocol, the PI or qualified delegate will 
conduct a virtual study visit, via phone or video conferencing, to assess the subject within 
target visit window date whenever possible. During the virtual study visit, the following 
information at minimum will be reviewed:
i)
Confirm if subject has experienced any adverse events (AEs)/serious adverse events 
(SAEs)/special situations (including pregnancy) and follow-up on any unresolved 
AE/SAEs.

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ii) Review current list of concomitant medications and document any new concomitant 
medications.
iii) If applicable, confirm electronic diary questionnaires and patient-reported outcomes 
have been completed and transmitted.
iv) If applicable, confirm subjects study drug supply is sufficient to last until the next 
planned visit date. If study drug resupply is needed it will be provided as described 
above in (1).
v) If applicable, remind subject to maintain current dosing and to keep all dispensed 
study drug kits for return at the next on-site visit.
b) Subjects may be unable or unwilling to travel to the site for planned assessments 
(eg, safety blood draws); hence samples may not be sent for central lab analyses.
Mitigation plan: Local labs may be utilized as appropriate to monitor subject safety until 
the subject can return to the site for their regular follow-up per protocol. Any laboratory 
assessments conducted at a local lab due to the pandemic will be documented 
accordingly. Pregnancy testing may be performed using a home urine pregnancy test if 
local lab pregnancy testing is not feasible.
c) Subjects may be unable or unwilling to attend the study visit to sign an updated informed 
consent form (ICF) version.
Mitigation plan: The site staff will follow their approved consent process and remain in 
compliance with local EC/IRB and national laws and regulations. Remote consent will be 
allowed if has been approved by the local EC/IRB. The consent process will be 
documented and confirmed by normal consent procedure at the earliest opportunity.
3) Protocol and monitoring compliance:
a) Protocol deviations may occur, in case scheduled visits cannot occur as planned per 
protocol.
Mitigation plan: If it is not possible to complete a required procedure, an unscheduled 
visit should be conducted as soon as possible when conditions allow. The situation should 
be recorded and explained as a protocol deviation. Any missed subject visits or deviation 
to the protocol due to the pandemic must be reported in the eCRF and described in the 
clinical study report. Any virtual study visits that are conducted in lieu of clinic visits due 
to the pandemic will be documented as a protocol deviation related to the pandemic.

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b) Monitors may be unable to carry out source data review or source data verification 
(SDV), or study drug accountability or assess protocol and GCP compliance. This may 
lead to delays in SDV, an increase in protocol deviations, or under reporting of AEs.
Mitigation plan: The study monitor is to remain in close communication with the site to 
ensure data entry and query resolution. In compliance with Gilead policy, a remote SDV 
should not be arranged). The study monitor is to reference the Study Monitoring Plan for 
guidance on how to conduct a remote monitoring visit. The study staff is to save and 
document all relevant communication in the study files. The status of sites that cannot 
accept monitoring visits and/or subjects on site, must be tracked centrally and updated on 
a regular basis.
4) Missing data and data integrity:
a) There may be an increased amount of missing data due to subjects missing 
visits/assessments. This could have an impact on the analysis and the interpretation of 
clinical trial data.
Mitigation plan: Implications of a pandemic on methodological aspects for the study will 
be thoroughly assessed and documented, and relevant actions will be taken as appropriate 
(ie, modification of the statistical analysis plan) and in compliance with Regulatory 
Authorities’ guidance. Overall, the clinical study report will describe the impact of the 
pandemic on the interpretability of study data.
Risks will be assessed continuously, and temporary measures will be implemented to mitigate 
these risks as part of a mitigation plan, as described above. These measures will be 
communicated to the relevant stakeholders as appropriate and are intended to provide alternate 
methods that will ensure the evaluation and assessment of the safety of subjects who are enrolled 
in this study.
Since these potential risks are considered mitigated with the implementation of these measures, 
the expected benefit-risk assessment of RDV in study subjects remains unchanged.

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Appendix 3.
Study Procedures Tables
Appendix Table 1.
Study Parts A and B: Study Procedures Table
Schedule of Assessments
Screening
TREATMENT PERIOD
FOLLOW-UP PERIOD
Day 1a
Day 2
Day 3
Day 4
Day 5
Day 7
Day 14
(± 3 days)
Day 28b 
(± 5 days)
Obtain Informed Consent
X
Inclusion/Exclusion Criteria
X
Medical History 
X
Documentation of SARS-CoV-2
X
ECGc
X
Complete or Symptom-Directed Physical 
Examination
X
X
X
X
X
X
X
X
Body Weight
X
Height
X
Vital Signs (Heart Rate, Temperature, Blood 
Pressure, SpO2)
X
X
X
X
X
X
X
X
Completion of Daily Adapted FLU-PRO©
Questionnaired
X
X
X
X
X
X
X
Chest X-Raye
X
FEV1
X
X
X
X
X
Safety Laboratory Assessments (Hematology, 
Chemistry, Coagulation)
X
X
X
X
X
Pregnancy Test (Urine)
X
Serum FSH Testf
X
Nasopharyngeal and Oropharyngeal Swabs 
and Saliva Samples for 
SARS-CoV-2 RT-qPCR Testing and Possible 
Viral Resistance Testing
X
X
X
X
X
X
X
Sparse Plasma PK Assessmentsg
X
X

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TREATMENT PERIOD 
FOLLOW-UP PERIOD 
Schedule of Assessments 
Screening 
Day 1• 
Day 2 
Day 3 
Day 4 
Day s 
Day 7 
Day 14 
(± 3 days) 
Day 28b 
(± 5 days) 
---------------------------------------
Inhaled Remdesivir for Injection Formulation 
X 
X 
X 
X 
X 
or PTM Administrationi 
Concomitant Medications 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse Events 
X 
X 
X 
X 
X 
X 
X 
X 
X 
ECG = electrocardiogram; FEY 1 = forced expiratory volume in the first second of expiration; FLU-PRO° = lnFLUenza Patient-Reported Outcome; 
FSH = follicle-stimulating hormone; PCR = polymerase chain reaction; PK = pharmacokinetic(s); RT-qPCR = quantitative reverse transcriptase polymerase 
chain reaction; RDV = (remdesivir, GS 5734-rM); SARS-CoY-2 = severe acute respiratory syndrome coronavirus 2; SpO2 = oxygen saturation as measured by 
pulse oximetry 
a 
b 
C 
d 
e 
f 
I 
If the screening and Day I visits occur on the same day, no procedures need to be repeated. 
Day 28 assessments may be completed by telephone. 
ECG will not be re.quired at screening. However, ECG should be perfom1ed prior to dosing on Day I. If subject randomizes and doses on the same day as screening, then 
ECG will be done at screening. 
Adapted FLU PRO° questionnaire is to be completed daily (Days I 14). 
Chest x ray will be perfom1ed at Day I. If screening visit and Day I are the same day, chest x ray does not need to be repeated if completed as SOC < 2 days before 
screening. 
Semm FSH test: Childbearing female participants who are not postmenopausal (see Appendix 5 who do not wish to follow protocol defined contraception will need a semm 
FSH test (FSH test is re.quired for women who are < 54 years old and have sto 
ed menstmating for 2: 12 months but do not have documentation of ovarian hom10nal failure) 
S arse lasma PK will be collected at Da I end ofnebulization 
and Da 3 
redose and end ofnebulization . 
Inhaled Remdes1vir for Injection fomrnlation will be administered to participants at the site under close supervision. Healthcare professionals administering inhaled 
Remdesivir for Injection fomrnlation should have the appropriate medication available for immediate use in case of hypersensitivity. The participant should be treated 
according to the SOC for management of hypersensitivity reaction. After dose administration, monitoring should be done as follows: Approximately 30 minutes post dose 
administration, participants should be observed, and vital signs should be perfom1ed prior to discharge. 
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Appendix Table 2.
Study Part C: Study Procedures Table
Schedule of Assessments
Screeninga
TREATMENT PERIOD
FOLLOW-UP PERIOD
Day 1b
Day 2
Day 3
Day 4
Day 5
Day 7
Day 14c
(± 3 days)
Day 28c
(± 5 days)
Obtain Informed Consent
X
Inclusion/Exclusion Criteria
X
Medical History 
X
Documentation of SARS-CoV-2d
X
Complete or Symptom-Directed Physical 
Examination
X
X
X
X
X
Body Weight
X
Height
X
Vital Signs (Heart Rate, Temperature, Blood 
Pressure, SpO2)
X
X
X
X
X
Completion of Daily Adapted FLU-PRO©
Questionnairee
X
X
X
X
X
X
X
FEV1
X
X
X
X
X
Safety Laboratory Assessments (Hematology, 
Chemistry, Coagulation)
X
X
X
X
Pregnancy Test (Urine)
X
Serum FSH Testf
X
Nasopharyngeal and Oropharyngeal Swabs and 
Saliva Samples for 
SARS-CoV-2 RT-qPCR Testing and Possible 
Viral Resistance Testing
X
X
X
X
Sparse/Single Plasma PK Assessmentsg
X
X
X

Remdesivir (RDV; GS-5734™)
Protocol GS-US-553-9020
FINAL
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
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13 January 2021
Schedule of Assessments
Screeninga
TREATMENT PERIOD
FOLLOW-UP PERIOD
Day 1b
Day 2
Day 3
Day 4
Day 5
Day 7
Day 14c
(± 3 days)
Day 28c
(± 5 days)
Remdesivir for Inhalation Solution Formulation or 
PTM Administrationh
X
X
X
X
X
Concomitant Medications
X
X
X
X
X
X
X
X
X
Adverse Events
X
X
X
X
X
X
X
X
X
COPD  chronic obstructive pulmonary disease; ECG  electrocardiogram; FEV1
forced expiratory volume in the first second of expiration; FLU PRO©
 InFLUenza 
Patient Reported Outcome; FSH  follicle stimulating hormone; PCR
polymerase chain reaction; PK  pharmacokinetic(s); RT qPCR  quantitative reverse transcriptase 
polymerase chain reaction; RDV  (remdesivir, GS 5734™); SARS CoV 2  severe acute respiratory syndrome coronavirus 2; SpO2
 oxygen saturation as measured by pulse 
oximetry
a
Study visits, with the exception of the screening visit, may be performed in clinic or at the participant’s home via home health and/or telehealth, virtually or remotely, as 
permitted by local and institutional regulations.
b
If the screening and Day 1 visits occur on the same day, no procedures need to be repeated.
c
Days 14 and 28 assessments may be completed by telephone.
d
Documentation of SARS CoV 2 infection first confirmed by nucleic acid testing or direct antigen testing with sample collected ≤ 4 days prior to randomization  
e
Adapted FLU PRO© questionnaire is to be completed daily (Days 1 14).
f
Serum FSH test: Childbearing female participants who are not postmenopausal (see Appendix 5) who do not wish to follow protocol defined contraception will need a serum 
FSH test (FSH test is required for women who are < 54 years old and have stopped menstruating for ≥ 12 months but do not have documentation of ovarian hormonal failure)
g
Sparse plasma PK will be collected at Days 3 and 5 (predose). A single anytime PK sample will be collected on Day 7 visit.
h
Remdesivir for Inhalation Solution formulation may be administered to participants in the participant’s home with in person or telehealth support. For participants with 
pre existing pulmonary conditions (ie, COPD or asthma) enrolled in Part C of the study, prescribed inhalers may not be used ≤30 minutes prior to Remdesivir for Inhalation 
Solution formulation administration. Healthcare professionals overseeing Remdesivir for Inhalation Solution formulation therapy remotely will observe the patient for any 
signs of adverse event. If any adverse event is observed and cannot be managed remotely, appropriate urgent care measures will be implemented. Approximately 30 minutes 
after dose administration, participants should be observed remotely prior to telehealth support session concluding.

Remdesivir (RDV; GS-5734T") 
Protocol GS-US-553-9020 
Gilead Sciences, Inc. 
FINAL 
Amendment3 
Appendix 4. 
Management of Clinical and Laboratory Adverse Events 
Grade 1 
Grade 2 
1: 
e 
on of 
May continue on th 
study at the discreti 
the invest gator 
" 
lfcoofirmed urrelated 
to the study drug. Oosing 
may contirue at the 
discretion of the 
ilvestigator 
CONFIDENTIAL 
Grade 3 
+ 
Repeat lab to coofinn 
tocicity grade 
' 
If confirmed and related 
to study drug, subject 
should be discontinued 
from thesrudy crug 
Page 75 
Grade 4 
-
If coofirmed and related to 
study drug, tl-e 
iwestigational prod.Jct 
should be discootinued and 
suqect managed according 
-, 
to bcal practice. Suq ect 
should be fol owed as 
clilically indi:ated lJlti the 
laboratory abnonnality 
returns to baseline, or is 
otherwise exp ailed 
13 January 2021 

Remdesivir (RDV; GS-5734™)
Protocol GS-US-553-9020
FINAL
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 76
13 January 2021
Appendix 5.
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 participant is considered of childbearing potential 
until becoming postmenopausal, 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 participant of any age.
b. Definition of Male Fertility
For the purposes of this study, a male born participant is considered of fertile after the initiation 
of puberty unless permanently sterile by bilateral orchidectomy or with medical documentation.
2) Contraception Requirements for Female Participants
a. Study Drug Effects on Pregnancy and Hormonal Contraception
In nonclinical reproductive toxicity studies, RDV demonstrated no adverse effect on embryofetal 
development when administered to pregnant animals. Embryonic toxicity was seen when RDV 
was initiated in female animals prior to mating and conception, but only a at a systemically toxic 
dose. RDV has not yet been studied in pregnant women. Before enrolling participants into 
studies with RDV, women of childbearing potential must have pregnancy testing performed at 
screening.
Available data indicate that RDV potentially causes an interaction with hormonal contraception, 
but the effect is considered to be of limited clinical significance. Hormonal methods must be 
used together with a barrier method.
Refer to the latest version of the IB for additional information.

Remdesivir (RDV; GS-5734™)
Protocol GS-US-553-9020
FINAL
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 77
13 January 2021
b. Contraception Requirements for Female Participants of Childbearing Potential
The inclusion of female participants of childbearing potential requires using at least an 
acceptable effective contraceptive measure. They must have a negative urine pregnancy test at 
screening prior to enrollment. In the event of a delayed menstrual period (over 1 month between 
menstruations), a pregnancy test must be performed to rule out pregnancy. This is applicable also 
for women of childbearing potential with infrequent or irregular periods. They must also agree to 
one of the following until Day 28:

Complete abstinence from intercourse of reproductive potential. Abstinence is an acceptable 
method of contraception only when it is in line with the participant’s preferred and usual 
lifestyle.
Or

Consistent and correct use of one of the following methods of birth control listed below:
Non-hormonal intrauterine device (IUD)
Hormonal IUD (must be used with a barrier method)
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

Barrier methods
Female barriers: Diaphragm with spermicide, cervical cap with spermicide, or sponge 
with spermicide
Male barriers: Male condom (with or without spermicide)
Or

Hormonal methods are restricted to drugs associated with the inhibition of ovulation. Each 
method must be used with a barrier method, preferably male condom. Hormonally-based 
contraceptives permitted for use in this protocol are as follows:
Oral contraceptives (either combined or progesterone only)
Injectable progesterone

Remdesivir (RDV; GS-5734™)
Protocol GS-US-553-9020
FINAL
Gilead Sciences, Inc. 
Amendment 3
CONFIDENTIAL
Page 78
13 January 2021
Subdermal contraceptive implant
Transdermal contraceptive patch
Contraceptive vaginal ring
Female participants must also refrain from egg donation and in vitro fertilization during 
treatment and until the last investigational product dose.
3)
Contraception Requirements for Male Participants
During the study, male participants with female partners of childbearing potential should use 
condoms until Day 28 when engaging in intercourse of reproductive potential.
4)
Unacceptable Birth Control Methods
Birth control methods that are unacceptable include periodic abstinence (eg, calendar, ovulation, 
symptothermal, postovulation methods), withdrawal (coitus interruptus), spermicides only, and 
lactational amenorrhea method. A female condom and a male condom should not be used 
together.
5)
Procedures to be Followed in the Event of Pregnancy
Participants will be instructed to notify the investigator and discontinue investigational product 
immediately, if they become pregnant at any time during the study. Participants 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 7.4.2.3.