A PHASE 2B, DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED, PARALLEL GROUP, DOSE RANGING STUDY TO EVALUATE VIROLOGICAL RESPONSE AND SAFETY OF ORAL PF-07817883 IN NON-HOSPITALIZED SYMPTOMATIC ADULT PARTICIPANTS WITH COVID-19
Phase: PHASE2
Conditions: SARS-CoV-2 Infection
Sponsor: Pfizer

PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 1
Title Page
A PHASE 2B, DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED, 
PARALLEL GROUP, DOSE RANGING STUDY TO EVALUATE VIROLOGICAL 
RESPONSE AND SAFETY OF ORAL PF-07817883 IN NON-HOSPITALIZED 
SYMPTOMATIC ADULT PARTICIPANTS WITH COVID-19
Study Intervention Number:
PF-07817883
Study Intervention Name:
NA
US IND Number:
162644
EudraCT Number:
NA
ClinicalTrials.gov ID:
NCT05799495
Pediatric Investigational Plan Number:
NA
Protocol Number:
C5091003
Phase:
2B
Sponsor Legal Address:
Pfizer Inc.
66 Hudson Boulevard East
New York, NY 10001
Brief Title:
A Phase 2B Study To Evaluate Virological Response and Safety of Oral PF-07817883 in 
Non-Hospitalized, Symptomatic, Adult Participants With COVID-19.
This document and accompanying materials contain confidential information belonging to Pfizer. Except 
as otherwise agreed to in writing, by accepting or reviewing these documents, you agree to hold this 
information in confidence and not copy or disclose it to others (except where required by applicable law) 
or use it for unauthorized purposes. In the event of any actual or suspected breach of this obligation, Pfizer 
must be promptly notified.
090177e19d31d7d8\Approved\Approved On: 14-Apr-2023 20:32 (GMT)

PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 2
Document History
Document
Version Date
Amendment 2
14 April 2023
Amendment 1
24 March 2023
Original protocol
01 February 2023
This amendment incorporates all revisions to date, including amendments made at the 
request of country health authorities and IRBs/ECs and any protocol administrative change 
letter(s).
Protocol Amendment Summary of Changes Table
Amendment 2 (14 April 2023)
Overall Rationale for the Amendment: To incorporate regulatory feedback on study 
population eligibility criteria.
Description of Change
Brief Rationale
Section # and Name
Substantial Modification(s)
Removed inclusion 
criterion #5, and updated 
inclusion criterion #2 and 
exclusion criterion #2 to 
prohibit enrollment of 
participants at high risk of 
progression to severe 
disease into this study.
To address comments 
received from the FDA.
Section 1.1 Synopsis, Section 
5.1 Inclusion Criteria and 
Section 5.2 Exclusion Criteria
Edited text to remove 
reference to participants at 
high risk of progression to 
severe disease.
To address comments 
received from the FDA.
Section 1.1 Synopsis (Ethical 
Considerations and Exclusion 
Criterion #12), Section 2.3.2 
Benefit Assessment, Section 
5.2 Exclusion Criteria and 
Section 6.9 Prior and 
Concomitant Therapy.
Added Safety Laboratory 
Assessments for Blood 
and Urine at the Day 10
visit.
To address comments 
received from the FDA.
Section 1.3 SoA
Removed collection of
retained research sample 
To reduce patient and 
operational burden by 
Section 1.3 SoA, Section 8.6.2 
Retained Research Samples for 
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 3
Description of Change
Brief Rationale
Section # and Name
for genetics (Prep D1) at 
Day 3, Day 5 and ET 
visits. Clarified that
collection of retained 
research sample for 
genetics (Prep D1) and 
retained research samples 
for biomarkers (Prep 
B2.5/R1) is optional.
removing redundant 
samples (Days 3 and 5 
and ET visits) and to 
address comments 
received from FDA 
(change retained research 
samples from mandatory 
to optional collections).
Genetics and Section 8.7.6 
Retained Research Samples for 
Biomarkers
Removed Sensitive 
CYP3A4 Substrates with 
Narrow Therapeutic Index
for alignment with
Section 6.9 Prior and 
Concomitant Therapy.
To address comments 
received from the FDA.
Section 10.9 Appendix 9:
Prohibited Concomitant 
Medications That May Result 
in DDI
Removed the sponsors 
definition of viral RNA 
rebound.
To address comments 
received from the FDA.
Section 10.11 Appendix 11: 
Definition of Viral RNA 
Rebound
Deleted “or other trial 
involving PF-07817883” 
from exclusion criterion 
#15.
To allow healthy 
participants from study 
C5091001 to enroll in this 
study if they develop 
COVID-19 at a later date.
Section 1.1 Synopsis and 
Section 5.2 Exclusion Criteria
Added discontinuation 
criteria for participants 
who develop AKI.
To comply with new 
updated guidance on the
evaluation of potential
acute kidney injury.
Section 7.1.1 Potential Cases 
of Acute Kidney Injury
Removed the option for 
home health visits.
Home health visits were 
underutilized in previous 
studies.
Section 1.1 Synopsis, Section 
1.3 SoA, Section 4.1 Overall 
Design, Section 8.1.3 Home 
Health Visits and Section 8.3.3 
Targeted Physical 
Examinations
Added additional reflex 
laboratory tests for DIKI 
in the right column of the 
table. Added laboratory 
tests for calculating 
UACR under “Urinalysis” 
column.
To comply with new 
updated guidance on 
evaluation of potential 
acute kidney injury.
Section 10.2 Appendix 2: 
Clinical Laboratory Tests
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 4
Description of Change
Brief Rationale
Section # and Name
Non-substantial Modification(s)
Edited Study Visit 
Location notes to specify 
that Day 33 visit should 
be conducted in-person if 
a NP sample needs to be 
collected.
Clarification that if a NP 
sample needs collecting 
on Day 33, this must be 
an in-person visit at the 
site.
Section 1.3 SoA and Section 
8.1.2 Telehealth Visits
Added text to specify that 
SARS-CoV-2 serology is 
a part of Other Laboratory 
Assessment and only Day 
1 and Day 10 sample will 
be assessed for SARS-
CoV-2 serology.
Clarification that SARS-
CoV-2 serology is 
evaluated with only Day 1
and Day 10 sample.
Section 1.3 SoA and Section 
10.2 Appendix 2: Clinical 
Laboratory Tests
Edited “through Day 28” 
to “over time” for the first 
two tertiary/exploratory 
endpoints listed. 
To better align with SAP 
reporting and SoA.
Section 3 Objectives, 
Endpoints, and Estimands
Added reference to viral 
RNA level assessment at 
Day 5.
Provide consistency with 
Section 1.1 Synopsis –
Statistical Methods.
Section 4.1 Overall Design
Removed reference to 
receiving dialysis for 
exclusion criterion #7.
Removed duplication 
since Chronic Kidney 
Disease requiring dialysis 
is already included in 
exclusion criterion #2.
Section 5.2 Exclusion Criteria
Edited total blood 
sampling volume.
To account for the Safety 
Laboratory Assessments 
added for Day 10 and the 
optional Day 21 retained 
research sample 
collection.
Section 8.1 Administrative and 
Baseline Procedures
Added a sentence to 
clarify the investigator 
will determine whether 
medical visits are 
considered COVID-19-
related.
To address comments 
received from the FDA.
Section 8.2.2 COVID-19-
Related Medical Visit Details
Removed collection of 
previous mAb treatment 
CRF will not require that 
all previous mAb 
Section 8.3.1 Medical History
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 5
Description of Change
Brief Rationale
Section # and Name
prior to the planned first 
dose of study drug.
treatment prior to the 
planned first dose of study 
drug be documented.
Addition of a sentence on 
reporting plan for 
exploratory endpoints.
Clarification that some 
exploratory endpoints 
may not be reported in the 
CSR.
Section 9.3.4 
Tertiary/Exploratory 
Endpoint(s) Analysis
Added “(urine)” to 
Albumin Urinalysis 
assessment.
Clarification that albumin 
assessment should be 
from a urine sample.
Section 10.2 Appendix 2: 
Clinical Laboratory Tests
Edited interim analysis 
plan specifications and 
blinding plan.
Clarifications on the 
planned protocol analysis.
Section 9.4 Interim Analyses
Minor edits in this 
section.
To comply with new 
regulatory requirements.
Section 7.1 Discontinuation of 
Study Intervention
Added NCT number.
ClinicalTrials.gov ID now 
available.
Title Page
Moved Amendment 1 
Summary of Change text 
and table into new 
Appendix 12.
To comply with new 
regulatory requirements.
Section 10.12 Appendix 12: 
Protocol Amendment History
Minor edits to clarify 
protocol text and correct 
minor errors and typos 
from previous versions.
To clarify protocol text 
and correct inadvertent 
errors.
Several sections throughout.
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 6
TABLE OF CONTENTS
LIST OF TABLES...................................................................................................................12
1. PROTOCOL SUMMARY...................................................................................................13
1.1. Synopsis ..................................................................................................................13
1.2. Schema ....................................................................................................................22
1.3. Schedule of Activities .............................................................................................23
2. INTRODUCTION ...............................................................................................................32
2.1. Study Rationale .......................................................................................................32
2.2. Background .............................................................................................................32
2.2.1. Nonclinical Studies of PF-07817883..........................................................32
2.2.2. Clinical Overview.......................................................................................33
2.2.2.1. Safety Overview........................................................................34
2.2.2.2. Summary of PF-07817883 Pharmacokinetics in Humans ........34
2.3. Benefit/Risk Assessment.........................................................................................36
2.3.1. Risk Assessment.........................................................................................37
2.3.2. Benefit Assessment.....................................................................................38
2.3.3. Overall Benefit/Risk Conclusion................................................................38
3. OBJECTIVES, ENDPOINTS, AND ESTIMANDS ...........................................................38
4. STUDY DESIGN.................................................................................................................40
4.1. Overall Design.........................................................................................................40
4.2. Scientific Rationale for Study Design.....................................................................40
4.2.1. Diversity of Study Population ....................................................................41
4.2.2. Choice of Contraception/Barrier Requirements .........................................42
4.2.3. Collection of Retained Research Samples..................................................42
4.3. Justification for Dose ..............................................................................................42
4.4. End of Study Definition ..........................................................................................43
5. STUDY POPULATION......................................................................................................43
5.1. Inclusion Criteria.....................................................................................................43
5.2. Exclusion Criteria....................................................................................................44
5.3. Lifestyle Considerations..........................................................................................47
5.3.1. Contraception..............................................................................................47
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 7
5.4. Screen Failures ........................................................................................................48
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY.................................48
6.1. Study Intervention(s) Administered........................................................................48
6.1.1. Administration............................................................................................50
6.2. Preparation, Handling, Storage, and Accountability...............................................50
6.2.1. Preparation and Dispensing........................................................................51
6.3. Assignment to Study Intervention...........................................................................51
6.4. Blinding...................................................................................................................52
6.4.1. Blinding of Participants..............................................................................52
6.4.2. Blinding of Site Personnel..........................................................................52
6.4.3. Blinding of the Sponsor..............................................................................52
6.4.4. Breaking the Blind......................................................................................52
6.5. Study Intervention Compliance...............................................................................53
6.6. Dose Modification...................................................................................................53
6.7. Continued Access to Study Intervention After the End of the Study......................54
6.8. Treatment of Overdose............................................................................................54
6.9. Prior and Concomitant Therapy ..............................................................................54
6.9.1. Rescue Medicine.........................................................................................55
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL...........................................................................56
7.1. Discontinuation of Study Intervention ....................................................................56
7.1.1. Potential Cases of Acute Kidney Injury .....................................................57
7.1.2. Liver Injury.................................................................................................58
7.1.3. ECG Changes..............................................................................................58
7.2. Participant Discontinuation/Withdrawal From the Study.......................................58
7.2.1. Withdrawal of Consent...............................................................................59
7.3. Lost to Follow-Up ...................................................................................................59
8. STUDY ASSESSMENTS AND PROCEDURES...............................................................59
8.1. Administrative and Baseline Procedures.................................................................59
8.1.1. Secondary Contacts ....................................................................................60
8.1.2. Telehealth Visits.........................................................................................61
8.2. Efficacy Assessments..............................................................................................61
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 8
8.2.1. Participant Diary.........................................................................................61
8.2.2. COVID-19-Related Medical Visit Details..................................................62
8.2.3. Daily Signs and Symptoms of COVID-19 .................................................62
8.2.4. Oxygen Support Details..............................................................................63
8.2.5. Global Impression Questions......................................................................63
8.3. Safety Assessments .................................................................................................63
8.3.1. Medical History ..........................................................................................64
8.3.2. Height and Weight......................................................................................64
8.3.3. Targeted Physical Examinations.................................................................64
8.3.4. Vital Signs ..................................................................................................64
8.3.4.1. Blood Pressure and Pulse Rate..................................................65
8.3.4.2. Temperature and Respiratory Rate............................................65
8.3.4.3. Oxygen Saturation Level...........................................................65
8.3.5. Electrocardiograms.....................................................................................65
8.3.6. Clinical Safety Laboratory Assessments ....................................................66
8.3.6.1. Alternative Facilities for Clinical Safety Laboratory 
Assessment ........................................................................................66
8.3.7. Pregnancy Testing ......................................................................................66
8.3.7.1. At-Home Pregnancy Testing.....................................................67
8.3.7.2. Evaluation for Menopause ........................................................67
8.3.8. Adjunctive Therapeutic Procedures............................................................67
8.4. Adverse Events, Serious Adverse Events, and Other Safety Reporting .................67
8.4.1. Time Period and Frequency for Collecting AE and SAE Information.......68
8.4.1.1. Reporting SAEs to Pfizer Safety...............................................68
8.4.1.2. Recording Nonserious AEs and SAEs on the CRF...................69
8.4.2. Method of Detecting AEs and SAEs ..........................................................69
8.4.3. Follow-Up of AEs and SAEs......................................................................69
8.4.4. Regulatory Reporting Requirements for SAEs...........................................69
8.4.5. Environmental Exposure, Exposure During Pregnancy or 
Breastfeeding, and Occupational Exposure.....................................................70
8.4.5.1. Exposure During Pregnancy......................................................70
8.4.5.2. Exposure During Breastfeeding ................................................72
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 9
8.4.5.3. Occupational Exposure .............................................................72
8.4.6. Cardiovascular and Death Events...............................................................72
8.4.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs..............................................................................72
8.4.8. Adverse Events of Special Interest.............................................................72
8.4.8.1. Lack of Efficacy........................................................................73
8.4.9. Medical Device Deficiencies......................................................................73
8.4.10. Medication Errors.....................................................................................73
8.5. Pharmacokinetics ....................................................................................................74
8.6. Genetics...................................................................................................................75
8.6.1. Specified Genetics ......................................................................................75
8.6.2. Retained Research Samples for Genetics ...................................................75
8.7. Biomarkers ..............................................................................................................75
8.7.1. Rapid Antigen Assessments .......................................................................76
8.7.2. Specified Gene Expression (RNA) Research .............................................76
8.7.3. Specified Protein Research.........................................................................76
8.7.4. Specified Metabolomic Research ...............................................................76
8.7.5. Viral RNA Level Assessments...................................................................76
8.7.6. Retained Research Samples for Biomarkers...............................................77
8.8. Immunogenicity Assessments.................................................................................77
8.9. Health Economics ...................................................................................................77
9. STATISTICAL CONSIDERATIONS ................................................................................77
9.1. Statistical Hypothesis ..............................................................................................77
9.1.1. Estimands....................................................................................................78
9.1.1.1. Primary Estimand......................................................................78
9.1.1.2. Secondary Estimands ................................................................78
9.1.2. Multiplicity Adjustment..............................................................................78
9.2. Analysis Sets ...........................................................................................................78
9.3. Statistical Analyses .................................................................................................79
9.3.1. General Considerations...............................................................................79
9.3.2. Primary Endpoint(s)/Estimand(s) Analysis ................................................80
9.3.2.1. Definition of Endpoint(s) ..........................................................80
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 10
9.3.2.2. Main Analytical Approach........................................................80
9.3.2.3. Supplementary Analyses...........................................................81
9.3.3. Secondary Endpoint(s)/Estimand(s) Analysis............................................81
9.3.4. Tertiary/Exploratory Endpoint(s) Analysis ................................................81
9.3.5. Other Safety Analyses ................................................................................81
9.3.5.1. Electrocardiogram Analyses......................................................81
9.3.6. Other Analyses............................................................................................81
9.4. Interim Analyses .....................................................................................................82
9.5. Sample Size Determination.....................................................................................82
9.6. Analysis of Pharmacokinetic Endpoints .................................................................83
9.6.1. Early PK/PD Unblinding Plan....................................................................83
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS..........................................................................................................84
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations...............84
10.1.1. Regulatory and Ethical Considerations ....................................................84
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP.........................................................................84
10.1.2. Financial Disclosure .................................................................................85
10.1.3. Informed Consent Process ........................................................................85
10.1.4. Data Protection .........................................................................................86
10.1.5. Committees Structure ...............................................................................86
10.1.5.1. Data Monitoring Committee ...................................................86
10.1.6. Dissemination of Clinical Study Data ......................................................87
10.1.7. Data Quality Assurance ............................................................................88
10.1.8. Source Documents....................................................................................89
10.1.9. Study and Site Start and Closure ..............................................................90
10.1.10. Publication Policy...................................................................................90
10.1.11. Sponsor’s Medically Qualified Individual..............................................91
10.2. Appendix 2: Clinical Laboratory Tests .................................................................92
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting .....................................................................93
10.3.1. Definition of AE .......................................................................................93
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Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 11
10.3.2. Definition of an SAE ................................................................................94
10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During 
the Active Collection Period............................................................................96
10.3.4. Reporting of SAEs....................................................................................99
10.4. Appendix 4: Contraceptive and Barrier Guidance ..............................................100
10.4.1. Male Participant Reproductive Inclusion Criteria..................................100
10.4.2. Female Participant Reproductive Inclusion Criteria...............................100
10.4.3. Woman of Childbearing Potential ..........................................................101
10.4.4. Contraception Methods...........................................................................102
10.5. Appendix 5: Genetics..........................................................................................104
10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments 
and Study Intervention Rechallenge Guidelines .....................................................105
10.7. Appendix 7: Kidney Safety Monitoring Guidelines ...........................................107
10.7.1. Laboratory Assessment of Change in Kidney Function and 
Detection of Kidney Injury............................................................................107
10.7.2. Age-Specific Kidney Function Calculation Recommendations.............107
10.7.2.1. Adults (18 Years and Above)—2021 CKD-EPI 
Equations.........................................................................................107
10.7.3. Adverse Event Grading for Kidney Safety Laboratory 
Abnormalities.................................................................................................107
10.8. Appendix 8: ECG Findings of Potential Clinical Concern .................................108
10.9. Appendix 9: Prohibited Concomitant Medications That May Result in DDI.....110
10.10. Appendix 10: Signs and Symptoms Attributable to COVID-19.......................112
10.11. Appendix 11: Definition of Viral RNA Rebound .............................................114
10.12. Appendix 12: Protocol Amendment History.....................................................115
10.13. Appendix 13: Abbreviations .............................................................................119
11. REFERENCES ................................................................................................................124
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Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
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LIST OF TABLES
Table 1.
Study Schedule of Assessment.................................................................23
.....35
.....36
Table 4.
Protocol Required Safety Laboratory Assessments..................................92
Table 5.
Signs and Symptoms Attributable to COVID-19 ...................................112
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CCI

PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 13
1. PROTOCOL SUMMARY 
1.1. Synopsis 
Protocol Title: 
A Phase 2B, Double-Blind, Randomized, Placebo-Controlled, Parallel Group, Dose Ranging 
Study to Evaluate Virological Response and Safety of Oral PF-07817883 in Non-
Hospitalized, Symptomatic, Adult Participants with COVID-19.
Brief Title:
A Phase 2B Virological Response and Safety Study of PF-07817883 in Non-Hospitalized,
Symptomatic, Adult Participants With COVID-19.
Regulatory Agency Identification Number(s):
US IND Number:
162644
EudraCT Number:
NA
ClinicalTrials.gov ID:
NCT05799495
Pediatric Investigational Plan Number:
NA
Protocol Number:
C5091003
Phase:
2B
Rationale:
The purpose of this study is to assess the effect of PF-07817883 on severe acute respiratory 
syndrome coronavirus 2 (SARS-CoV-2) ribonucleic acid (RNA) level reduction in 
nasopharyngeal (NP) samples and to evaluate the safety of PF-07817883 treatment in non-
hospitalized, symptomatic, adult participants with coronavirus disease 2019 (COVID-19).
The study is designed as a dose-ranging study to collect pharmacological and safety 
information to inform dose selection of PF-07817883 in later stage Phase 2/3 studies.
Objectives, Endpoints, and Estimands:
Objectives
Endpoints
Estimands
Primary: 
Primary:
Primary: 
! To describe the effect of
PF-07817883 treatment versus 
placebo on SARS-CoV-2 RNA 
levels in NP samples in non-
hospitalized symptomatic adult 
participants with COVID-19.
! Change from baseline in SARS-
CoV-2 RNA level on Day 5.
! E1: The estimand is the difference 
between the PF-07817883 dose groups 
and placebo in mean change from 
baseline in SARS-CoV-2 RNA level in 
NP samples in the population of non-
hospitalized, symptomatic, adult 
participants with COVID-19 who have 
SARS-CoV-2 RNA level 
≥4 log10 copies/mL at baseline. This 
analysis will exclude data after use of 
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PF-07817883
Protocol C5091003
Final Protocol Amendment 2, 14 April 2023
PFIZER CONFIDENTIAL
CT02-GSOP Clinical Protocol Template Phase 1 2 3 4 (01 April 2022)
TMF Doc ID: 164.01
Page 14
Objectives
Endpoints
Estimands
prohibited COVID-19 medications and 
after study treatment discontinuation.
Secondary: 
Secondary:
Secondary: 
! To describe the effect of 
PF-07817883 treatment versus 
placebo on SARS-CoV-2 RNA
levels in NP samples in non-
hospitalized symptomatic adult 
participants with COVID-19.
! Change from baseline in SARS-
CoV-2 RNA level on Days 3, 10 
and 14.
! E1: The estimand is the difference 
between the PF-07817883 dose groups 
and placebo in mean change from 
baseline in SARS-CoV-2 RNA level in 
NP samples in the population of non-
hospitalized, symptomatic, adult 
participants with COVID-19 who have 
SARS-CoV-2 RNA level 
≥4 log10 copies/mL at baseline. This 
analysis will exclude data after use of 
prohibited COVID-19 medications and 
after study treatment discontinuation.
! To describe the safety and 
tolerability of PF-07817883
relative to placebo in the 
treatment of non-hospitalized, 
symptomatic, adult participants 
with COVID-19.
! Incidence of treatment-emergent 
adverse events (TEAEs).
! Incidence of serious adverse 
events (SAEs) and adverse events 
(AEs) leading to discontinuations.
! Incidence of clinically significant 
abnormal laboratory values, vital 
signs, and electrocardiograms 
(ECGs).
! Not applicable (NA).
Overall Design:
This is a Phase 2B, double-blind, randomized, placebo-controlled, parallel group, dose 
ranging study to assess the effect of PF-07817883 treatment on SARS-CoV-2 RNA level 
reduction in NP samples in non-hospitalized, symptomatic, adult participants with 
COVID-19. Approximately 228 eligible participants with a confirmed diagnosis of SARS-
CoV-2 infection are planned to be randomized into the study to ensure approximately 180 
participants with baseline SARS-CoV-2 RNA level ≥4 log10 copies/mL complete the study. 
Participants will be randomized in a 1:1:2:2 ratio to receive PF-07817883 100, 300, or 600 
mg, or placebo orally every 12 hours (q12h) for 5 days (10 doses total). Study visits should 
take place at the investigational site.
The total study duration is up to 5 weeks and includes a screening period of no more than 
48 hours before randomization, study intervention for 5 days and a 4-week follow-up period 
after the last administration of the study intervention.
Number of Participants:
Approximately 228 participants will be randomly assigned to study intervention to provide 
~180 completers with baseline SARS-CoV-2 RNA level ≥4 log10 copies/mL.
Note: "Enrolled" means a participant's, or his or her legally authorized representative’s, 
agreement to participate in a clinical study following completion of the informed consent 
process and screening. A participant will be considered enrolled if the informed consent is 
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not withdrawn prior to participating in any study activity after screening. Potential 
participants who are screened for the purpose of determining eligibility for the study, but do 
not participate in the study, are not considered enrolled, unless otherwise specified by the 
protocol. 
Intervention Groups and Duration:
Participants will be screened within 48 hours before randomization. Eligible participants will 
receive PF-07817883 (100, 300 or 600 mg) or placebo orally q12h for 5 days. The total study 
duration is up to 5 weeks and includes a screening period of no more than 48 hours, study 
intervention for 5 days and a 4-week follow-up period after the last administration of the 
study intervention.
Data Monitoring Committee or Other Independent Oversight Committee: Yes
An independent internal review committee (IRC) will review unblinded data to ensure the 
safety of participants throughout the duration of the study, as specified in the IRC Charter. In 
addition to safety reviews, the IRC will review the interim analysis.
Details of the IRC are specified in the IRC Charter.
Study Population:
Inclusion and exclusion criteria are listed below:
Inclusion Criteria 
Participants must meet the following inclusion criteria to be eligible for enrollment into the 
study:
Age and Sex:
1. Participants who are willing and able to comply with all scheduled visits, treatment 
plan, laboratory tests, lifestyle considerations, and other study procedures.
2. Participants ≥18 to <65 years of age at the time of the Screening Visit.
!
Woman/women of childbearing potential (WOCBP) may be enrolled.
!
All fertile participants must agree to use a highly effective method of 
contraception.
Disease Characteristics:
3. Confirmed SARS-CoV-2 infection as determined by rapid antigen testing (RAT) in 
nasal specimen collected within 48 hours prior to randomization. Investigator sites 
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will use test kits that are authorized for use in this study and the test result must be 
available to confirm eligibility.
4. Initial onset of signs/symptoms attributable to COVID-19 within 5 days prior to the 
day of randomization and at least 1 of the specified signs/symptoms attributable to 
COVID-19 present on the day of randomization.
Exclusion Criteria
Participants with any of the following characteristics/conditions will be excluded:
1. Current need for hospitalization or anticipated need for hospitalization within 24h 
after randomization in the clinical opinion of the site investigator.
Medical conditions:
2. Has at least 1 characteristic or underlying medical condition (self-report is 
acceptable) associated with an increased risk of developing severe illness from 
COVID-19. The list of the characteristics or conditions includes:
!
Body mass index (BMI) ≥30 kg/m2;
!
Current smoker (cigarette smoking within the past 30 days) and history of at least 
100 lifetime cigarettes;
!
Chronic lung disease (ie, bronchiectasis, chronic obstructive pulmonary disease, 
interstitial lung disease, pulmonary embolism, pulmonary hypertension);
!
Asthma, requiring daily prescribed therapy;
!
Cardiac vascular disease, defined as history of any of the following: myocardial 
infarction, stroke, transient ischemic attack, heart failure, angina with prescribed 
nitroglycerin, coronary artery bypass graft, percutaneous coronary intervention, 
carotid endarterectomy, and aortic bypass;
!
Type 1 or Type 2 diabetes mellitus;
!
Chronic Kidney Disease requiring dialysis;
!
Neurodevelopmental disorders (eg, cerebral palsy, Down’s syndrome) or other 
conditions that confer medical complexity (eg, genetic or metabolic syndromes 
and severe congenital anomalies);
!
Active cancer other than localized skin cancer, including those requiring 
treatment (including palliative treatment), as long as the treatment is not among 
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the prohibited medications that must be administered/continued during the trial 
period;
!
Medical-related technological dependence (eg, CPAP [continuous positive airway 
pressure] [not related to COVID-19]).
3. Known medical history of active liver disease, including chronic or active hepatitis B 
or C infection, primary biliary cirrhosis, Child-Pugh Class B or Class C, or acute liver 
failure.
4. History of hypersensitivity or other contraindication to any of the components of the 
study interventions, as determined by the investigator.
5. Suspected or confirmed concurrent active systemic infection other than COVID-19 
that may interfere with the evaluation of response to the study intervention.
6. Immunocompromised with ≥1 of the following:
a.
Solid organ (eg, liver, heart, lung or kidney) transplant recipient who is 
receiving immunosuppressive therapy.
b. Receipt of chimeric antigen receptor (CAR)-T-cell therapy or hematopoietic 
cell transplantation (HCT) either within 2 years of transplantation or receiving 
immunosuppressive therapy.
c.
Moderate or severe primary immunodeficiency (eg, DiGeorge syndrome, 
Wiskott-Aldrich syndrome).
d. Use of at least 1 of the following immune-weakening medications:
i.
Has received corticosteroids equivalent to prednisone ≥20 mg daily for 
at least 14 consecutive days within 30 days prior to study entry.
ii.
Active treatment causing significant immunosuppression, including 
alkylating agents, antimetabolites, transplant-related 
immunosuppressive drugs, cancer chemotherapeutic agents, tumor 
necrosis factor (TNF) blockers, or other highly immunosuppressive 
drugs such as biologics.
e.
Hematological malignancy (including leukemia, lymphoma and myeloma) or 
active immunosuppressive treatment for solid tumor.
f.
Human immunodeficiency virus (HIV) infection with CD4 cell count <200 
mm3 from known medical history within the past 6 months of screening.
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7. Known severe renal impairment (estimated glomerular filtration rate [eGFR] of 
<30 mL/min/1.73 m2 within 6 months of the screening visit, using the serum 
creatinine-based chronic kidney disease epidemiology [CKD-EPI] formula).
8. Oxygen saturation of <92% on room air obtained at rest within 24h prior to 
randomization.
a.
NOTE: For a potential participant who regularly receives chronic 
supplementary oxygen for an underlying lung condition, oxygen saturation 
should be measured while on their standard home oxygen supplementation.
9. Any comorbidity requiring hospitalization and/or surgery within 7 days prior to study 
entry, or that is considered life threatening within 30 days prior to study entry, as 
determined by the investigator.
10. Other medical or psychiatric condition including recent (within the past year) or 
active suicidal ideation/behavior or laboratory abnormality that may increase the risk 
of study participation or, in the investigator’s judgment, make the participant 
inappropriate for the study.
Prior Concomitant Therapy:
11. Current use of any prohibited concomitant medication(s).
12. Use of any locally available oral or injectable antiviral medication intended to treat 
symptomatic SARS-CoV-2 infection before and at enrollment are excluded. After 
enrollment, locally available SARS-CoV-2 treatment (including but not limited to 
molnupiravir, mAbs, outpatient IV remdesivir, convalescent plasma) will be 
permitted per investigator judgement. Note: PAXLOVID is contraindicated to be 
administered concurrently with the study intervention due to drug-drug interation
(DDI) risk.
13. Expected to receive any dose of a SARS-CoV-2 vaccine within 14 days of 
randomization or during the study.
Prior/Concurrent Clinical Study Experience:
14. Current or previous administration with an investigational product (drug or vaccine) 
within 30 days (or as determined by the local requirement) or 5 half-lives preceding 
the first dose of study intervention used in this study (whichever is longer). 
Authorized or products with conditional approval are not considered investigational.
15. Known prior participation in this trial.
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Diagnostic Assessments:
16. Laboratory assessments not required at screening unless deemed necessary by the 
investigator to confirm eligibility. If deemed necessary, laboratory assessments at 
screening will be performed at local laboratory. The medical laboratory test 
abnormalities within 6 months prior to screening must be closely assessed. If 
abnormalities cannot be verified, consider conducting local laboratory testing at 
screening to confirm eligibility for the study.
17. Known history of any of the following abnormalities in clinical laboratory tests 
(within past 6 months of the screening visit):
!
Total bilirubin (T bili) ≥2 × upper limit of normal (ULN) (except for Gilbert’s 
syndrome)
!
Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≥2.5 ×
ULN
!
Absolute neutrophil count <1000/mm3.
18. Baseline standard 12-lead ECG that demonstrates clinically relevant abnormalities 
that may affect participant safety or interpretation of study results (eg, QTc corrected 
using Fridericia’s formula [QTcF] >450 ms, complete left bundle branch block
(LBBB), signs of acute myocardial infarction, ST-T interval changes suggestive of 
myocardial ischemia, second- or third-degree atrioventricular (AV) block, or serious 
bradyarrhythmias or tachyarrhythmias). If the baseline uncorrected QT interval is 
>450 ms, this interval should be rate corrected using the Fridericia method only and 
the resulting QTcF should be used for decision making and reporting. If QTcF 
exceeds 450 ms, or QRS exceeds 120 ms, the ECG should be repeated twice and the 
average of the 3 QTcF or QRS values used to determine the participant’s eligibility. 
Computer-interpreted ECGs should be overread by a physician experienced in 
reading ECGs before excluding a participant.
Other Exclusion Criteria: 
19. Females who are pregnant or breastfeeding.
20. Investigator site staff directly involved in the conduct of the study and their family 
members, site staff otherwise supervised by the investigator, and sponsor and sponsor 
delegate employees directly involved in the conduct of the study and their family 
members.
Study Arms and Duration:
Eligible participants for this study will be randomly assigned (1:1:2:2) to receive 
PF-07817883 100, 300 or 600 mg, or placebo orally q12h as specified in the table below.
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Study Intervention(s)
Intervention 
Name
PF-07817883
PF-07817883
PF-07817883
Placebo for 
PF-07817883*
Arm Name
(group of 
participants 
receiving a 
specific treatment 
or no treatment)
PF-07817883 
100 mg q12h
PF-07817883 
300 mg q12h
PF-07817883 
600 mg q12h
Placebo
Unit Dose 
Strength(s)
100 mg
300 mg
600 mg
0 mg
Route of 
Administration
Oral
Oral
oral
Oral
Use
Experimental
experimental
experimental
Placebo
IMP or 
NIMP/AxMP
IMP
IMP
IMP
IMP
* 2 tablet types for placebo to match with PF-07817883 100 mg and 300 mg, respectively.
AxMP=auxiliary medicinal product; IMP=investigational medicinal product; NIMP=noninvestigational medicinal 
product.
Study Arm(s)
Arm Title
PF-07817883 
100 mg q12h
PF-07817883 
300 mg q12h
PF-07817883 
600 mg q12h
Placebo
Arm Type
Experimental
Experimental
Experimental
Placebo
Arm Description
Participants will 
receive 
PF-07817883 
100 mg q12h for 
5 days.
Participants will 
receive 
PF-07817883 
300 mg q12h for 
5 days.
Participants will 
receive 
PF-07817883 
600 mg q12h for 
5 days.
Participants will 
receive 0 mg q12h 
for 5 days.
Statistical Methods:
A sufficient number of participants will be screened to achieve a total of approximately 228 
participants, with participants randomly assigned to PF-07817883 100, 300, 600 mg or 
placebo q12h in approximately a 1:1:2:2 ratio. Assuming 20% of participants will 
discontinue study drug treatment or have a baseline SARS-CoV-2 RNA level <4 log10
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copies/mL, approximately 180 participants (60 in each of PF-07817883 600 mg q12h and 
placebo, and 30 in each of PF-07817883 100 and 300 mg q12h) with baseline SARS-CoV-2 
RNA level ≥4 log10 copies/mL are expected to complete Day 5 of the study. Additional
participants may be randomized to ensure 180 participants with baseline SARS-CoV-2 RNA 
level ≥4 log10 copies/mL who complete study drug treatment.
The sample size is based on the primary efficacy endpoint, change from baseline in SARS-
CoV-2 RNA level at Day 5. 
 
The primary estimand is the difference between the PF-07817883 dose groups and placebo in 
mean change from baseline in SARS-CoV-2 RNA level in NP samples on Day 5 in the 
population of non-hospitalized, symptomatic, adult participants with COVID-19 who have 
SARS-CoV-2 RNA level ≥4 log10 copies/mL at baseline. This will exclude data after use of 
prohibited COVID-19 medications and after study treatment discontinuation. The primary 
analysis will be a Bayesian Emax model applied to the estimates from a mixed model for 
repeated measures (MMRM) analysis.
A planned formal interim analysis for virological response and safety may be performed to 
assess SARS-CoV-2 RNA level after approximately 50% or more participants, ie, at least 
114 participants with baseline SARS-CoV-2 RNA level ≥4 log10 copies/mL, complete their 
study participation (including viral load assessment) through Day 5. The timing of the 
interim analysis is contingent on the recruitment rate.
Ethical Considerations:
This study is a placebo-controlled trial that will be conducted in participants with 
symptomatic COVID-19 infection who are at standard risk of progressing to severe disease, 
defined as <65 years of age and without underlying medical conditions associated with 
increased risk of developing severe illness from COVID-19 (as outlined in exclusion 
criterion #2). Participants enrolled may benefit from treatment with an antiviral. Although 
participants may be randomized to placebo, these are participants who are not expected to 
receive other locally available antiviral therapies outside the conduct of this trial. For this
standard risk population currently there is no locally approved standard of care (SoC)
treatment available; thus placebo was selected as the appropriate comparator.
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CCI
CCI

PF-07817883
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The trial-specific risks and burdens for participants includes the requirement to return for 
follow up visits, they may experience discomforts undergoing study assessments (eg, blood 
samples, ECGs), and they may develop AEs due to study intervention.
1.2. Schema
N = number of completers.
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1.3. Schedule of Activities
The SoA table provides an overview of the protocol visits and procedures. Refer to the STUDY ASSESSMENTS AND 
PROCEDURES section of the protocol for detailed information on each procedure and assessment required for compliance with the 
protocol. 
The investigator may schedule visits (unplanned visits) in addition to those listed in the SoA table, in order to conduct evaluations or 
assessments required to protect the well-being of the participant.
Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
Study Visit Location
S
S
T
S
T
S
S
S
S
S/T
S/(T)
! Day 33 visit should be conducted in-person at the 
investigational site [S] if NP sample must be 
collected.
! Telehealth visits [T] may be conducted in-person at 
the discretion of the investigator. 
! ET – if visit occurs after Day 21 may be conducted 
by telehealth at the discretion of the investigator.
ELIGIBILITY
Informed consent
X
! See Section 10.1.3.
Verify inclusion/ 
exclusion criteria
X
! See Section 5.1 and Section 5.2.
Demographics and 
medical history
X
! See Section 8.3.1.
PHYSICAL EXAMINATION & VITAL SIGNS
Targeted physical 
examination 
X
X
X
X
X
X
X
X
X
! See Section 8.3.3.
! Collect at Day 33 visit if participant is symptomatic.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
Weight, height
X
! See Section 8.3.2. Height may be self-reported.
Vital signs
X
X
X
X
X
X
X
X
X
! See Section 8.3.4.
! Collect at Day 33 visit if participant is symptomatic.
12-lead ECG
X
X
X
X
X
! Triplicate ECG collected at baseline prior to dosing.
! Day 1 Post-dose ECGs should be performed within 
30 to 90 min post-dose. 
! If ET visit occurs before final ECG assessment on 
Day 10 visit, ECG should be performed.
! If Day 10 visit is missed, then ECG should be 
performed at Day 14.
! See Section 8.3.5 for additional information.
LABORATORY ASSESSMENTS
Safety Laboratory 
Assessments
(Blood) –
Hematology and 
Chemistry
X
X
X
X
X
! See Section 8.3.6 and Appendix 2.
! Day 1 labs must be collected prior to first dose of 
study intervention.
! Laboratory assessments not required at screening 
unless deemed necessary by the investigator to 
confirm eligibility. If deemed necessary, laboratory 
assessments at screening will be performed at local 
laboratory. The medical laboratory test abnormalities 
Safety Laboratory 
Assessments 
(Urine)
– Urinalysis
X
X
X
X
X
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
Other Laboratory 
Assessments
X
X
X
X*
X
within 6 months prior to screening must be closely 
assessed. If abnormalities cannot be verified, 
consider conducting local laboratory testing at 
screening to confirm eligibility for the study. 
! SARS-CoV-2 serology is a part of Other Laboratory 
Assessment (see Appendix 2). Only Day 1 and Day 
10 samples will be assessed for SARS-CoV-2 
serology. 
*Day 10: only SARS-CoV-2 serology assessment will 
be done.
Pregnancy test
(WOCBP only)
X
X
X
! Additional Pregnancy tests will be done whenever 1 
menstrual cycle is missed or when potential 
pregnancy is otherwise suspected.
! See Section 8.3.7.
FSH
X
! When FSH testing is required to confirm 
postmenopausal status, a participant may be 
screened in the study prior to the test result being 
available as long as the FSH test result confirms 
postmenopausal status prior to dosing.
! See Section 8.3.7.2 and Appendix 2.
BIOMARKER ASSESSMENTS
Rapid antigen 
testing
X
! Confirmed SARS-CoV-2 infection as determined by 
RAT using a test kit that is authorized by the sponsor
in a nasal specimen collected within 2 days prior to 
randomization is required.
! See Section 8.7.1.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
SARS-CoV-2 RNA 
level assessment
(NP)
X
X
X
X
X
X
X*
X
! See Section 8.7.5.
! Day 1 NP sample should be collected prior to first 
dose of study intervention.
! If a participant experiences symptom worsening or 
recurrence after completion of the 5-day treatment 
with study drug (ie, through Day 33), participants 
may subsequently attend a site for an unscheduled 
visit, for NP sample collection to measure SARS-
CoV-2 RNA levels.
*Day 33 NP sample should be collected only if 
participant is symptomatic at Day 21.
Specified protein 
research (plasma 
biomarkers)
X
X
X
X
! Day 1 sample should be collected prior to first dose 
of study intervention.
! See Section 8.7.3.
Retained research 
sample for genetics 
(Prep D1)
X
! Sample collection is optional.
! Prep D1 Retained Research Samples; if not collected 
on the designated collection day, collect at the next 
available time point when biospecimens are being 
collected in conjunction with a participant visit.
! Refer to Section 8.6.2.
Retained research 
samples for 
biomarkers (Prep 
B2.5, Prep R1) 
X
X
X
X
X
! Sample collections are optional.
! Day 1 sample should be collected prior to first dose 
of study intervention.
! See Section 8.7.6.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
PK ASSESSMENTS
PK sample (PF-
07817883)
X
X
X
X
! On Day 1 only, three blood samples for PK will be 
collected at 30±10, 60±15 and 90±15 minutes post-
dose to remain at the site.
! On Day 3, one blood sample for PK will be collected 
at any time during the study visit.
! On Day 5, one blood sample for PK will be 
collected. The preferred time of sample collection is 
predose up to 2 hours before study intervention 
administration; if a predose sample collection is not 
possible, collect this sample at any time during the 
visit, even after study intervention has been 
administered.
! Refer to Section 8.5.
Sample for blood to 
plasma ratio
X
! Blood to plasma ratio sample will be collected at
60±15 minutes post-dose. Do NOT centrifuge.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
PK micro-sampling 
(PF-07817883)
X
X
X
! PK micro-sample(s) will be collected by Tasso 
micro-sampling device on Day 1, 60±10 min post-
dose simultaneously with the PK sample draw.
! A Tasso micro-sample will be self-collected at home
before administration of the second dose. This can 
occur on Day 1 evening if first dose is taken in the 
morning or on Day 2 morning if first dose is taken in 
the evening on Day 1.
! Self-collected at home by Tasso micro-sampling 
device at the following timepoints:
! Day 2 before the evening dose, 
! Day 4 after the morning dose at the following 
times: 1 sample between 30 to 90 minutes, 1 
sample between 2 to 6 hours, and 1 sample 8 to 
12 hours after the dose (the last sample should 
be collected before the evening dose).
! Tasso micro-sampling can occur regardless of 
whether this coincides with a site visit.
! Refer to Section 8.5.
RANDOMIZATION
Randomization
X
! At randomization, the participant enrollment number 
and dose level allocation are assigned.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
STUDY INTERVENTION
Study intervention 
administration 
Day 1 through Day 5
(10 doses total)
! If 1 dose was administered on Day 1, study 
intervention administration should end on Day 6
(total 10 doses).
! All subsequent doses may be self-administered 
outside the study clinic (eg, at home).
! See Section 6.1 for additional information.
CONCOMITANT TREATMENT(S)
Prior/concomitant 
medication(s)
X
X
X
X
X
X
X
X
X
! See Section 6.9.
Adjunctive
therapeutic 
procedures
X
X
X
X
X
X
X
X
X
! Will be collected through the Day 33 visit.
! Please see Section 8.3.8.
STUDY PROCEDURES& ASSESSMENTS
Collect/update 
secondary contacts
X
X
X
! See Section 8.1.1.
Record 
supplemental 
oxygen 
requirements
X
X
X
X
X
X
X
X
X
! See Section 8.2.4.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
Participant-
completed study 
diary (revised 
COVID-19 signs 
and symptoms, and 
global impression 
questions)
Every day from Day 1 through Day 29
! Revised COVID-19 signs and symptom eDiary 
assessments should be completed pre-dose, prior to 
other study procedures such as ECG recordings and 
laboratory assessments.
! See Section 8.2.1 and Section 8.2.5.
Staff review of 
study diary
X
X
X
X
X
X
! See Section 8.2.1.
Participant-
completed study 
intervention log
Day 1 through Day 5
! Study intervention log should be completed daily on 
Day 1 through Day 6 if only 1 dose was 
administered on Day 1.
! See Section 6.5.
Record COVID-19-
related medical 
visits
X
X
X
X
X
X
X
! COVID-19-related medical visits a participant has 
attended since the last assessment will be collected.
! See Section 8.2.2.
Retrieval of unused 
study intervention 
and empty study 
intervention 
containers
X
X
X
X
! If the Day 5 visit is conducted prior to last dose of 
study intervention, the study intervention log, empty 
study intervention containers, and unused study 
intervention should be returned at the next in-person 
visit.
! See Section 6.5.
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Table 1.
Study Schedule of Assessment
Visit Identifier
Abbreviations used in 
this table may be found 
in Appendix 13
Screen
Treatment Period
F/U
ET
(prior 
to Day
33)
Notes:
Screening
Day -1
Baseline 
Day [1]
Day 
[2]
Day
[3]
Day 
[4]
Day
[5]/
EOT
Day
[10]
Day
[14]
Day 
[21]
Day 
[33
(28+5)]
/EOS
Visit Window
Day -1 to 
Day 1
0 days
NA
±1 
day
NA
±1 day ±1 day
±2 
days
±2 days +5 days +3 days
Although there is a 3-day window for the Day 5 visit, 
sites should encourage participants to attend on Day 
5 to optimize evaluation of RNA level change at Day 
5.
Study intervention 
accountability
X
X
X
X
X
X [if 
needed]
! Study intervention accountability is also performed 
at the Day 10 visit if the participant administered 
treatment after the Day 5 visit was conducted.
! Study intervention accountability check at Day 2 and 
Day 4 will be an optional phone call.
! See Section 6.5.
Contraception 
check 
X
X
X
X
X
X
X
X
X
! See Section 5.3.1.
Vital status check
X
X
! Verify mortality status of participants, if needed.
! See Section 8.1.1.
Serious and 
nonserious AE 
monitoring
X
X
X
X
X
X
X
X
X
X
X
! AEs should be assessed by means of a telehealth
visit if not possible via an in-person visit.
! See Section 8.4 for additional information.
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2. INTRODUCTION
PF-07817883 is a potent and selective inhibitor of the SARS-CoV-2 Mpro, that is being 
developed as an oral treatment in patients with COVID-19.
2.1. Study Rationale 
The purpose of this study is to assess the effect of PF-07817883 on SARS-CoV-2 RNA level
reduction in NP samples and to evaluate the safety of PF-07817883 treatment in non-
hospitalized, symptomatic, adult participants with COVID-19. The study is designed as a 
dose-ranging study to collect pharmacological and safety information to inform dose 
selection of PF-07817883 in later stage Phase 2/3 studies.
2.2. Background
In December 2019, COVID-19 was identified as a new, potentially fatal, respiratory infection 
caused by the novel coronavirus, SARS-CoV-2. The WHO declared COVID-19 a Public 
Health Emergency of International Concern on 20 January 2020 and further characterized the 
disease outbreak as a pandemic on 11 March 2020.1
COVID-19 manifests as a wide range of illnesses, from asymptomatic infection to severe 
pneumonia, ARDS, and death. While the majority of cases (approximately 80%) are 
asymptomatic or mild,2 patients who are hospitalized with COVID-19 may have significant 
morbidity and mortality,3,4 and are at increased risk of developing complications such as 
ARDS, acute cardiac injury, thromboembolic events and/or kidney injury.5-7 Moreover, other 
comorbidities, such as hypertension, obesity, and diabetes, as well as older age and male sex 
increase the risk for worse outcomes.8,9
The coronavirus Mpro is a virally encoded enzyme that is critical to the SARS-CoV-2
replication cycle, analogous to other obligatory virally encoded proteases (eg, HIV protease, 
HCV protease). Mutagenesis experiments with other coronaviruses and picornaviruses that 
are related to SARS-CoV-2 (picornavirus-like supercluster) have demonstrated that the 
activity of the Mpro is essential for viral replication. No close human analogs of coronavirus 
Mpro enzymes are known, suggesting that appropriate Mpro inhibitors may function as 
selective inhibitors of SARS-CoV-2 and other coronaviruses as therapeutic agents.
Inhibition of the SARS-CoV-2 Mpro by PAXLOVID has demonstrated the efficacy of an 
antiviral in the reduction in hospitalization and death in mild-to-moderate COVID-19 
patients with high risk of progression to severe disease. But some high-risk patients may be 
ineligible for PAXLOVID due to DDIs. Hence, there remains an important need for 
additional safe and more effective therapeutic interventions.
2.2.1. Nonclinical Studies of PF-07817883
Data from nonclinical studies support the planned clinical trials with PF-07817883; these 
studies are described in the IB.
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PF-07817883 exhibits broad spectrum inhibitory activity across the Coronaviridae family of 
Mpro enzymes.
In vitro, the antiviral activity of PF-07817883 against SARS-CoV-2 was evaluated in several 
cell lines. In all cellular systems tested, PF-07817883 demonstrates potent antiviral activity 
against SARS-CoV-2. In dNHBE cells, a physiologically relevant, primary human lung 
alveolar epithelial cell line, PF-07817883 inhibited SARS-CoV-2 viral replication with an 
EC50 of 
μM and EC90 of
μM after 3 days of drug exposure. PF-07817883 also 
exhibited antiviral efficacy against SARS-CoV-1, HCoV-229E, and MERS-CoV in cellular 
systems. In addition, PF-07817883 demonstrated antiviral activities against Alpha, Beta, 
Delta, Gamma, Lambda, Mu, and Omicron variants in the Vero TMPRSS2 and VeroE6 P-gp 
KO cells.
In accordance with FDA and EMA DDI guidance,
 
 
The toxicity of PF-07817883 was evaluated in
 
 There were 
no adverse findings in any of the studies. From a preliminary population PK model based on 
FIH data, the total Cmax and AUC24 for 600 mg BID 
 
, respectively. The NOAELs in the
studies 
 
over the human unbound Cmax and AUC24 at a dose of 
600 mg BID. 
 
More details are presented in the IB.
2.2.2. Clinical Overview
C5091001 is the first clinical study using PF-07817883. It is a six-part study. PART-1 is a 
SAD study, PART-2 is a MAD study, PART-3 is a rBA/FE study, PART 4 is a ME study, 
PART-5 is a DDI study and PART-6 is a SE study.
PART-1 included 2 interleaving cohorts with a total of 16 participants with 3-period cross-
over in each cohort. For each period, up to 6 participants received a single oral dose of 
PF-07817883 and up to 2 participants received placebo. Single doses of PF-07817883 ranged 
from 150 mg to 4000 mg. 
 in Cohort 1 were 
 
 and Other 
 
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PART-2 included 3 cohorts evaluating safety, tolerability, and PK data at 200 mg, 600 mg, 
and 1500 mg doses of PF-07817883 or placebo administered BID for up to 10 days. As of 18 
January 2023, 18 participants were randomized in 3 cohorts in PART-2. 
 
 in Cohort 4 (PF-07817883 600 mg BID or placebo) of PART-2 due to Other 
(
).
PART-4 included a single cohort of 6 male participants to evaluate the metabolism and 
excretion of a single dose of PF-07817883 600 mg. Cohort 11 of PART-5 included 14 
participants and evaluated the effect of steady state PF-07817883 600 mg on PK of 
midazolam in healthy participants.
2.2.2.1. Safety Overview
The preliminary data collected (data snapshot 18 January 2023) in PART-1, PART-2, and 
(data snapshot 06 February 2023) in PART-4 and PART-5 (Cohort 11) of the Phase 1 study 
(C5091001) demonstrated an acceptable safety profile at single doses of PF-07817883 or 
placebo ranging from 150 mg to 4000 mg in PART-1, doses of 200 mg to 1500 mg BID of 
PF-07817883 or placebo for 10 days in PART-2, and 600 mg BID in PART-4 and 
PART-5. Dose escalation stopping rules were not triggered and MTD was not achieved. 
There have been no deaths, SAEs or SUSARs reported. 
 
 
 
 
 
There were no obvious trends in, or 
association of, TEAEs with dose level of PF-07817883 in PART-1, PART-2, PART-4, or 
PART-5 (Cohort 11); however, the small numbers of participants studied at each dose level 
do not permit any definitive conclusions about the relationship between dose and tolerability.
Further details on the clinical safety of PF-07817883 are provided in the current IB.
2.2.2.2. Summary of PF-07817883 Pharmacokinetics in Humans
 
 
 
 
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Further details on the clinical PK of PF-07817883 are provided in the current IB.
2.3. Benefit/Risk Assessment
The purpose of the study is to generate safety, tolerability and PK data for further clinical
development of PF-07817883 as a potential new, pharmacological agent for the treatment of 
COVID-19. PF-07817883 has been evaluated in non-clinical studies and in an ongoing study 
(C5091001) in healthy adult participants.
More detailed information about the known and expected benefits and risks and reasonably 
expected AEs of PF-07817883 may be found in the Investigator’s Brochure, which is the 
SRSD for this study.
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2.3.1. Risk Assessment
Potential Risk of Clinical Significance
Summary of Data/Rationale for Risk
Mitigation Strategy
Study Intervention(s) PF-07817883
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2.3.2. Benefit Assessment
PF-07817883 has been shown to have SARS-CoV-2 antiviral activity in vitro and is intended 
to reduce virus titers, thereby reducing the duration and severity of symptoms and the risk of 
mortality in SARS-CoV-2 infected patients. The PF-08717883 doses administered in this 
study are expected to have clinically relevant antiviral effects. On this basis, the potential 
benefit to individual study participants who receive the study intervention may include a 
shorter time to clinical recovery, prevention of hospitalization, and a lower probability of 
progressing to more severe illness or death. The potential benefit of the study is that it may 
provide a new treatment option for non-hospitalized patients with COVID-19 who are at 
standard risk for progression to severe disease and hospitalization. In the context of the 
global pandemic public health emergency, this treatment could play an important role in 
alleviating current pressures on health care systems globally.
2.3.3. Overall Benefit/Risk Conclusion
Taking into account the ongoing COVID-19 global pandemic, the continued high mortality 
and morbidity burden, the potential for future epidemic outbreaks, the limited outpatient 
treatment options available and the measures taken to minimize risk to participants in this 
study, the potential risks identified in association with PF-07817883 are justified by the 
anticipated benefits that may be afforded to participants with COVID-19. The participants
enrolled into this study will include those at standard risk of progression to severe disease, 
and so the benefit for this population may be considered modest. However, this study will 
provide information needed to that will help determine the correct dose to use in high-risk 
populations. An independent IRC will be responsible for monitoring the safety of participants 
at regularly scheduled intervals throughout the duration of the study and for assessing 
efficacy and futility at the time of the planned interim analysis according to the IRC Charter.
3. OBJECTIVES, ENDPOINTS, AND ESTIMANDS
Objectives
Endpoints
Estimands
Primary: 
Primary:
Primary: 
! To describe the effect of 
PF-07817883 treatment versus 
placebo on SARS-CoV-2 RNA 
levels in NP samples in non-
hospitalized symptomatic adult 
participants with COVID-19.
! Change from baseline in SARS-
CoV-2 RNA level on Day 5.
! E1: The estimand is the difference 
between the PF-07817883 dose groups 
and placebo in mean change from 
baseline in SARS-CoV-2 RNA level in 
NP samples in the population of non-
hospitalized, symptomatic, adult 
participants with COVID-19 who have 
SARS-CoV-2 RNA level 
≥4 log10 copies/mL at baseline. This 
analysis will exclude data after use of 
prohibited COVID-19 medications and 
after study treatment discontinuation.
Secondary: 
Secondary:
Secondary: 
! To describe the effect of 
PF-07817883 treatment versus 
placebo on SARS-CoV-2 RNA
levels in NP samples in non-
! Change from baseline in SARS-
CoV-2 RNA level on Days 3, 10, 
and 14.
! E1: The estimand is the difference 
between the PF-07817883 dose groups 
and placebo in mean change from 
baseline in SARS-CoV-2 RNA level in 
NP samples in the population of non-
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Objectives
Endpoints
Estimands
hospitalized symptomatic adult 
participants with COVID-19.
hospitalized, symptomatic, adult 
participants with COVID-19 who have 
SARS-CoV-2 RNA level 
≥4 log10 copies/mL at baseline. This 
analysis will exclude data after use of 
prohibited COVID-19 medications and 
after study treatment discontinuation.
! To describe the safety and 
tolerability of PF-07817883
relative to placebo in the 
treatment of non-hospitalized, 
symptomatic, adult participants 
with COVID-19.
! Incidence of TEAEs.
! Incidence of SAEs and AEs 
leading to discontinuations.
! Incidence of clinically significant 
abnormal laboratory values, vital 
signs, and ECGs.
! NA
Tertiary/Exploratory:
Tertiary/Exploratory:
Tertiary/Exploratory:
! To assess the effect of 
PF-07817883 treatment on the 
duration and severity of signs 
and symptoms in non-
hospitalized, symptomatic, 
adult participants with 
COVID-19.
! Proportion of participants with any 
targeted signs and symptoms 
attributed to COVID-19 over time .
! Proportion of participants with any
targeted severe sign or symptom 
attributed to COVID-19 over time.
! Number of participants with 
sustained alleviation of all targeted 
signs/symptoms over time.
! Number of participants with 
sustained resolution of all targeted 
signs and symptoms over time.
! Duration of targeted COVID-19 
sign or symptom.
! Progression to a worsening status 
in 1 or more self-reported COVID-
19-associated symptoms over time.
! Proportion of participants with 
symptom rebound at Day 10, 14, 
and 21.
! NA
! To assess the effect of
PF-07817883 treatment on
COVID-19-related medical 
visits, hospitalization or death 
and all-cause mortality in non-
hospitalized, symptomatic, 
adult participants with COVID-
19.
! Proportion of participants with 
COVID-19 related medical visits
or hospitalization, over time. 
! Proportion of participants with 
death (all cause) over time. 
! Number of days in hospital and 
ICU stay in participants with 
COVID-19 related hospitalization 
over time.
! NA
! To determine the PK of 
PF-07817883 in non-
hospitalized, symptomatic, 
adult participants with COVID-
19.
! PF-07817883 PK in plasma and 
whole blood (if feasible).
! NA
! To describe the effect of 
PF-07817883 treatment versus 
placebo on SARS-CoV-2 RNA
levels in NP samples in non-
! Change from Day 5 in SARS-CoV-
2 RNA level at Days 10, 14 and 21.
! Change from baseline in SARS-
CoV-2 RNA levels at Days 21 and 
33.
! NA
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Objectives
Endpoints
Estimands
hospitalized symptomatic adult 
participants with COVID-19.
! Proportion of participants with 
SARS-CoV-2 RNA level <LLOQ 
in NP samples over time.
! Proportion of participants with 
viral rebound at Day 10, Day 14, or 
Day 21.
! To describe the effect of 
PF-07817883 treatment on 
infectivity of SARS-CoV-2 
collected from NP samples.
! Change from baseline in SARS-
CoV-2 infectious titer on Days 3, 5, 
10 and 14, and Days 21 and 33 (if 
data permit).
! NA
4. STUDY DESIGN
4.1. Overall Design
This is a Phase 2B, double-blind, randomized, placebo-controlled, parallel group, dose 
ranging study to assess the effect of PF-07817883 treatment on SARS-CoV-2 RNA level
reduction in NP samples in non-hospitalized, symptomatic, adult participants with 
COVID-19. Approximately 228 eligible participants with a confirmed diagnosis of SARS-
CoV-2 infection are planned to be randomized into the study to ensure approximately 180
participants with baseline SARS-CoV-2 RNA level ≥4 log10 copies/mL complete the study
drug treatment. Participants will be randomized in a 1:1:2:2 ratio to receive PF-07817883
100, 300, or 600 mg, or placebo orally q12h for 5 days (10 doses total). Study visits should 
take place at the investigational site.
The total study duration is up to 5 weeks and includes a screening period of no more than 
48 hours before randomization, study intervention for 5 days and a 4-week follow-up period
after the last administration of the study intervention.
An independent IRC will review unblinded data to ensure the safety of participants 
throughout the duration of the study, as specified in the IRC Charter. In addition to safety
reviews, the IRC will review the following:
!
A planned formal interim analysis for virological response and safety may be 
performed to assess SARS-CoV-2 RNA level after approximately 50% or more 
participants, ie, at least 114 participants with baseline SARS-CoV-2 RNA level ≥4 
log10 copies/mL, complete their study participation (including viral load assessment) 
through Day 5. The timing of the interim analysis will be contingent on the 
recruitment rate.
Subsequent to the planned interim analysis, there will be 1 planned analysis for reporting the 
results of this study. The primary analysis will be performed after all participants have 
completed the Day 33 visit.
4.2. Scientific Rationale for Study Design
This study evaluates the safety and the potential effect of an investigational agent on 
reducing SARS-CoV-2 viral RNA level. The study is designed as a dose-ranging study to 
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collect pharmacological activity and safety information to facilitate dose selection for later 
stage studies.
Although mAbs and antivirals have since become available there remains an important need 
to develop therapeutics for the treatment of COVID-19 infection. Several mAbs became 
available under EUA for the treatment of mild-to-moderate COVID-19 infection in select 
populations. However, mAbs such as bamlanivimab with etesivimab, sotrovimab, and more 
recently bebtelovimab have since been removed as treatment options due to diminished 
efficacy with the emergence of SARS-CoV-2 variants.10,11 Antivirals such as PAXLOVID
and remdesivir IV are available and considered preferred therapy for non-hospitalized adults, 
while molnupiravir is considered an alternative therapy by the COVID-19 Treatment 
Guidelines Panel.11 However, these therapeutics are limited to outpatient populations with 
mild-to-moderate COVID-19 infection at risk for progressing to severe disease. Furthermore, 
some high-risk patients may be ineligible for PAXLOVID due to DDIs, and remdesivir may 
be inaccessible for some patients as it requires administration in a health care setting and 
returning for 3 subsequent days for daily IV dosing.
Despite these advances, there remains an important need for additional safe and more 
effective therapeutic interventions that do not require administration in a healthcare setting, 
are not limited by DDIs, and with a risk/benefit profile supportive of administration to a 
broader patient population. The direct reduction of viral replication, through inhibition of 
other critical viral enzymes, offers an important mechanism as monotherapy or in 
combination, to achieve greater patient benefit.
Efficacy assessments (including participant reported COVID-19-related symptoms and 
severity, and COVID-19-related medical visits) will be collected through Day 33. The 
symptom endpoint includes those recommended by FDA and relies on targeted symptoms
that have been associated with COVID-19, and which are expected to be dynamic and 
improve with effective anti-SARS-CoV-2 therapy. NP samples will be collected at specified 
timepoints to assess SARS-CoV-2 RNA level over time.
This study uses a randomized, double-blind, placebo-controlled design, which is a well-
accepted approach for evaluating efficacy in a clinical research setting. Placebo was selected 
as the comparator since as of this date there is no globally approved SoC treatment for this 
patient population. Participants in either treatment group may receive SoC therapy so long as 
it is not prohibited under Section 5.1 or Appendix 9.
4.2.1. Diversity of Study Population
Diversity of study population in this protocol applies to sites in the US only. The diversity 
strategy will include sites with the potential to support the recruitment of diverse populations. 
Reasonable attempts will be made to enroll participants to ensure the study population is 
representative of the patient population that will be treated with PF-07817883 in clinical 
practice. The following strategies may be explored in support of diverse recruitment efforts:
!
Selecting sites that have access to diverse participants within their locale.
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Creating and completing individual site recruitment plans in collaboration with sites.
!
Have proactive discussions with investigator sites throughout the enrollment period to 
assess and reevaluate site specific strategies as needed to best position each site for 
the most diverse representation enrollment outcomes.
!
Developing recruitment and retention materials with culturally and linguistically 
appropriate language and imagery to resonate with underrepresented populations.
!
Translating all patient-facing materials into US Spanish.
!
Providing investigators with recruitment materials for both potential participants and 
other HCPs.
!
Educating site staff on the importance of including diverse participants.
!
Monitor diverse enrollment to identify potential opportunities to include diverse 
populations.
4.2.2. Choice of Contraception/Barrier Requirements 
Studies to evaluate the developmental toxicity of PF-07817883 have not been 
conducted. Therefore, the use of a highly effective method of contraception is required (see 
Appendix 4).
4.2.3. Collection of Retained Research Samples
Retained Research Samples will be collected and stored for further analyses which may, for 
example, provide greater understanding of the study intervention.
4.3. Justification for Dose
The dosing regimens to be evaluated in this study are placebo, 100, 300 and 600 mg 
PF-07817883 q12h administered orally for 5 days. Dose selection for this study included 
consideration of all relevant available preclinical and clinical data, including repeat-dose 
toxicology studies, clinical safety, and PK data from the ongoing Phase 1 study (C5091001), 
and in vitro pharmacology studies with PF-07817883.
A preliminary population PK model was developed using PK data (unaudited) from the 
single ascending dose and multiple ascending dose parts of the Phase 1 study (C5091001). 
Following the first dose of 100, 300 and 600 mg of PF-07817883 q12h, median unbound 
(total) Ctrough of PF-07817883 are predicted to be approximately 43 (92), 119 (253) and 226 
(482) ng/mL, ie, approximately 1.3, 3.5 and 6.6-fold higher than the in vitro EC90 (total) of 
ng/mL determined in dNHBE cells (equivalent to free in vitro EC90 of 70 nM, fu, 
human=
), respectively. As the majority of antivirals are administered to maintain 
concentrations either at or above the EC90, lower doses below 100 mg are not planned for this 
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study. At the selected dose levels of 100, 300 and 600 mg q12h, for a hypothetical inter-
subject variability of 60%, more than 63, 96 and 99% of the participants, respectively, are 
predicted to maintain free PF-07817883 concentrations above the in vitro EC90 over the 
12-hour dosing interval.
The selected duration is based on the effectiveness demonstrated following 5-day 
administration of other antiviral agents used including PAXLOVID, molnupiravir and 
remdesivir in the treatment of COVID-19.
Preliminary safety data from study C5091001, collected up to 22 December 2022, showed an 
acceptable safety profile for single doses of PF-07817883 ranging from 150 mg to 4000 mg 
and for 10-day repeated doses ranging from 200 mg BID to 1500 mg BID.
The proposed dosing regimen of 100, 300 and 600 mg of PF-07817883 q12h administered 
orally for 5 days is thus expected to be safe and efficacious.
4.4. End of Study Definition
The end of the study is defined as the date of the last visit of the last participant in the study 
shown in the SoA for the last participant in the trial globally.
A participant is considered to have completed the study if they have completed all periods of 
the study, including the last visit as shown in the SoA.
5. STUDY POPULATION
This study can fulfill its objectives only if appropriate participants are enrolled, including 
participants across diverse and representative racial and ethnic backgrounds. If a 
prescreening tool is utilized for study recruitment purposes, it will include collection of 
information that reflects the enrollment of a diverse participant population including, where 
permitted under local regulations, age, sex, race, and ethnicity. The following eligibility 
criteria are designed to select participants for whom participation in the study is considered 
appropriate. All relevant medical and nonmedical conditions should be taken into 
consideration when deciding whether a particular participant is suitable for this protocol.
Prospective approval of protocol deviations to recruitment and enrollment criteria, also 
known as protocol waivers or exemptions, is not permitted.
5.1. Inclusion Criteria
Participants are eligible to be included in the study only if all of the following criteria apply:
Age and Sex:
1. Participants who are willing and able to comply with all scheduled visits, treatment 
plan, laboratory tests, lifestyle considerations, and other study procedures.
2. Participants ≥18 to <65 years of age at the time of the Screening Visit.
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!
WOCBP may be enrolled.
!
All fertile participants must agree to use a highly effective method of 
contraception. Refer to Appendix 4 for reproductive criteria for male (Section 
10.4.1) and female (Section 10.4.2) participants.
Disease Characteristics:
3. Confirmed SARS-CoV-2 infection as determined by RAT in nasal specimen collected 
within 48 hours prior to randomization. Investigator sites will use test kits that are 
authorized for use in this study and the test result must be available to confirm 
eligibility.
4. Initial onset of signs/symptoms attributable to COVID-19 within 5 days prior to the 
day of randomization and at least 1 of the specified signs/symptoms attributable to 
COVID-19 present on the day of randomization (see Appendix 10 for criteria).
5.2. Exclusion Criteria
Participants are excluded from the study if any of the following criteria apply:
1. Current need for hospitalization or anticipated need for hospitalization within 24h 
after randomization in the clinical opinion of the site investigator.
Medical conditions:
2. Has at least 1 characteristic or underlying medical condition (self-report is 
acceptable) associated with an increased risk of developing severe illness from 
COVID-19. The list of the characteristics or conditions includes:
!
BMI ≥30 kg/m2;
!
Current smoker (cigarette smoking within the past 30 days) and history of at least 
100 lifetime cigarettes;
!
Chronic lung disease (ie, bronchiectasis, chronic obstructive pulmonary disease, 
interstitial lung disease, pulmonary embolism, pulmonary hypertension);
!
Asthma, requiring daily prescribed therapy;
!
Cardiac vascular disease, defined as history of any of the following: myocardial 
infarction, stroke, transient ischemic attack, heart failure, angina with prescribed 
nitroglycerin, coronary artery bypass graft, percutaneous coronary intervention, 
carotid endarterectomy, and aortic bypass;
!
Type 1 or Type 2 diabetes mellitus;
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!
Chronic Kidney Disease requiring dialysis;
!
Neurodevelopmental disorders (eg, cerebral palsy, Down’s syndrome) or other 
conditions that confer medical complexity (eg, genetic or metabolic syndromes 
and severe congenital anomalies);
!
Active cancer other than localized skin cancer, including those requiring 
treatment (including palliative treatment), as long as the treatment is not among 
the prohibited medications that must be administered/continued during the trial 
period;
!
Medical-related technological dependence (eg, CPAP [not related to COVID-19]).
3. Known medical history of active liver disease, including chronic or active hepatitis B 
or C infection, primary biliary cirrhosis, Child-Pugh Class B or Class C, or acute liver 
failure.
4. History of hypersensitivity or other contraindication to any of the components of the 
study interventions, as determined by the investigator.
5. Suspected or confirmed concurrent active systemic infection other than COVID-19 
that may interfere with the evaluation of response to the study intervention.
6. Immunocompromised with ≥1 of the following:
a.
Solid organ (eg, liver, heart, lung or kidney) transplant recipient who is 
receiving immunosuppressive therapy.
b. Receipt of CAR-T-cell therapy or HCT either within 2 years of transplantation 
or receiving immunosuppressive therapy.
c.
Moderate or severe primary immunodeficiency (eg, DiGeorge syndrome, 
Wiskott-Aldrich syndrome).
d. Use of at least 1 of the following immune-weakening medications:
i.
Has received corticosteroids equivalent to prednisone ≥20 mg daily for 
at least 14 consecutive days within 30 days prior to study entry.
ii.
Active treatment causing significant immunosuppression, including 
alkylating agents, antimetabolites, transplant-related 
immunosuppressive drugs, cancer chemotherapeutic agents, TNF 
blockers, or other highly immunosuppressive drugs such as biologics.
e.
Hematological malignancy (including leukemia, lymphoma and myeloma) or 
active immunosuppressive treatment for solid tumor.
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f.
HIV infection with CD4 cell count <200 mm3 from known medical history 
within the past 6 months of screening.
7. Known severe renal impairment (eGFR of <30 mL/min/1.73 m2 within 6 months of
the screening visit, using the serum creatinine-based CKD-EPI formula12).
8. Oxygen saturation of <92% on room air obtained at rest within 24h prior to 
randomization.
a.
NOTE: For a potential participant who regularly receives chronic 
supplementary oxygen for an underlying lung condition, oxygen saturation 
should be measured while on their standard home oxygen supplementation.
9. Any comorbidity requiring hospitalization and/or surgery within 7 days prior to study 
entry, or that is considered life threatening within 30 days prior to study entry, as 
determined by the investigator.
10. Other medical or psychiatric condition including recent (within the past year) or 
active suicidal ideation/behavior or laboratory abnormality that may increase the risk 
of study participation or, in the investigator’s judgment, make the participant 
inappropriate for the study.
Prior/Concomitant Therapy:
11. Current use of any prohibited concomitant medication(s). Refer to Section 6.9 Prior 
and Concomitant Therapy.
12. Use of any locally available oral or injectable antiviral medication intended to treat 
symptomatic SARS-CoV-2 infection before and at enrollment are excluded. After 
enrollment, locally available SARS-CoV-2 treatment (including but not limited to 
molnupiravir, mAbs, outpatient IV remdesivir, convalescent plasma) will be 
permitted per investigator judgement. Note: PAXLOVID is contraindicated to be 
administered concurrently with the study intervention due to DDI risk (refer to 
Section 6.9).
13. Expected to receive any dose of a SARS-CoV-2 vaccine within 14 days of 
randomization or during the study.
Prior/Concurrent Clinical Study Experience:
14. Current or previous administration with an investigational product (drug or vaccine) 
within 30 days (or as determined by the local requirement) or 5 half-lives preceding 
the first dose of study intervention used in this study (whichever is longer). 
Authorized or products with conditional approval are not considered investigational.
15. Known prior participation in this trial.
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Diagnostic Assessments:
16. Laboratory assessments not required at screening unless deemed necessary by the 
investigator to confirm eligibility. If deemed necessary, laboratory assessments at 
screening will be performed at local laboratory. The medical laboratory test 
abnormalities within 6 months prior to screening must be closely assessed. If 
abnormalities cannot be verified, consider conducting local laboratory testing at 
screening to confirm eligibility for the study.
17. Known history of any of the following abnormalities in clinical laboratory tests 
(within past 6 months of the screening visit):
!
T bili ≥2 × ULN (except for Gilbert’s syndrome)
!
AST or ALT ≥2.5 × ULN
!
Abs neutrophil count <1000/mm3.
18. Baseline standard 12-lead ECG that demonstrates clinically relevant abnormalities 
that may affect participant safety or interpretation of study results (eg, QTcF 
>450 ms, complete LBBB, signs of acute myocardial infarction, ST-T interval 
changes suggestive of myocardial ischemia, second- or third-degree AV block, or 
serious bradyarrhythmias or tachyarrhythmias). If the baseline uncorrected QT 
interval is >450 ms, this interval should be rate corrected using the Fridericia method 
only and the resulting QTcF should be used for decision making and reporting. If 
QTcF exceeds 450 ms, or QRS exceeds 120 ms, the ECG should be repeated twice
and the average of the 3 QTcF or QRS values used to determine the participant’s 
eligibility. Computer-interpreted ECGs should be overread by a physician 
experienced in reading ECGs before excluding a participant.
Other Exclusion Criteria:
19. Females who are pregnant or breastfeeding.
20. Investigator site staff directly involved in the conduct of the study and their family 
members, site staff otherwise supervised by the investigator, and sponsor and sponsor 
delegate employees directly involved in the conduct of the study and their family 
members.
5.3. Lifestyle Considerations
5.3.1. Contraception 
The investigator or their designee, in consultation with the participant, will confirm that the 
participant is utilizing an appropriate method of contraception for the individual participant 
and his or her partner(s) from the permitted list of contraception methods (see Appendix 4,
Section 10.4.4) and will confirm that the participant has been instructed in its consistent and 
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correct use. At time points indicated in the SoA, the investigator or designee will inform the 
participant of the need to use highly effective contraception consistently and correctly and 
document the conversation and the participant’s affirmation in the participant’s chart.
Participants need to affirm their consistent and correct use of at least 1 of the selected 
methods of contraception, considering that their risk for pregnancy may have changed since 
the last visit. 
In addition, the investigator or designee will instruct the participant to call immediately if the 
selected contraception method is discontinued and document the requirement to use an 
alternate protocol-specified method, including if the participant will no longer use abstinence 
as the selected contraception method, or if pregnancy is known or suspected in the participant 
or partner.
5.4. Screen Failures
Screen failures are defined as participants who consent to participate in the clinical study but 
are not subsequently enrolled in the study. A minimal set of screen failure information is 
required to ensure transparent reporting of screen failure participants to meet the CONSORT 
publishing requirements and to respond to queries from regulatory authorities. Minimal 
information includes demography, screen failure details, eligibility criteria, and any SAE.
Individuals who do not meet the criteria for participation in this study (screen failure) may 
not be rescreened.
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY
Study interventions are all prespecified investigational and medicinal products, medical 
devices, and other interventions (eg, surgical and behavioral) intended to be administered to 
the study participants during the study conduct.
For the purposes of this protocol, study intervention refers to PF-07817883 100 mg, 300 mg 
and 600 mg (2 x 300 mg) or matching placebo tablets.
6.1. Study Intervention(s) Administered
Study Intervention(s)
Intervention 
Name
PF-07817883
PF-07817883
PF-07817883
Placebo for 
PF-07817883
Arm Name
(group of 
participants
receiving a 
specific 
treatment or no 
treatment)
PF-07817883
100 mg q12h
PF-07817883
300 mg q12h
PF-07817883
600 mg q12h
Placebo
Type
Drug
Drug
Drug
Placebo
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Study Intervention(s)
Dose 
Formulation
Tablet
Tablet
Tablet
Tablet*
Unit Dose 
Strength(s)
100 mg
300 mg
300 mg
0 mg
Dosage Level(s)
100 mg q12h for 
5 days
300 mg q12h for 
5 days
600 mg q12h for 
5 days
0 mg q12h for 
5 days
Route of 
Administration
Oral
Oral
Oral
Oral
Use
Experimental
Experimental
Experimental
Placebo
IMP or 
NIMP/AxMP
IMP
IMP
IMP
IMP
Sourcing
Provided centrally 
by the sponsor.
Refer to the IPM.
Provided centrally 
by the sponsor.
Refer to the IPM.
Provided centrally 
by the sponsor.
Refer to the IPM.
Provided centrally 
by the sponsor.
Refer to the IPM.
Packaging and 
Labeling
Study intervention 
will be provided in 
bottles. Each bottle
will be labeled as 
required per country 
requirement.
Products will be 
provided with 
blinded labels.
Study intervention 
will be provided in
bottles. Each bottle 
will be labeled as 
required per country 
requirement. 
Products will be 
provided with 
blinded labels.
Study intervention 
will be provided in 
bottles. Each bottle 
will be labeled as 
required per country 
requirement. 
Products will be 
provided with 
blinded labels.
Study intervention 
will be provided in 
bottles. Each bottle 
will be labeled as 
required per country 
requirement. 
Products will be 
provided with 
blinded labels.
Current/
Former 
Name(s) or 
Alias(es)
PF-07817883
PF-07817883
PF-07817883
NA
* 2 tablet types for placebo to match with PF-07817883 100 mg and 300 mg, respectively.
Study Arm(s)
Arm Title
PF-07817883 
100 mg
PF-07817883 
300 mg
PF-07817883 
600 mg
Placebo
Arm Type
Experimental
Experimental
Experimental
Placebo
Arm
Description
Participants will 
receive PF-07817883 
100 mg q12h from 
Day 1 through 
Day 5.
Participants will 
receive PF-07817883 
300 mg q12h from 
Day 1 through 
Day 5.
Participants will 
receive PF-07817883 
600 mg q12h from 
Day 1 through 
Day 5.
Participants will 
receive placebo 0 mg 
q12h from Day 1 
through Day 5.
Associated 
Intervention 
Labels
PF-07817883 
(100 mg q12h)
PF-07817883 
(300 mg q12h)
PF-07817883 
(600 mg q12h)
Placebo q12h
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6.1.1. Administration
PF-07817883 100 mg, 300 mg and 600 mg or matching placebo tablets will be taken every 
12 hours for 5 days. Participants will be dispensed 3 bottles on Day 1 and should take 1 tablet 
from each bottle every 12 hours. All three tablets should be taken within 5 minutes. 
Participants will swallow the study intervention whole, and will not manipulate or chew the 
study intervention prior to swallowing.
Participants are required take the first dose of study intervention on Day 1, during the in-
person visit. All subsequent doses may be self-administered outside the study clinic (eg, at 
home). The study intervention should be taken every 12 hours (±4 hours), and not more than 
twice in a calendar day. Depending on the time of first dose, the timing of the second dose 
may be adjusted slightly to allow the participant/caregiver to select a convenient 12 hour 
dosing schedule as long as the next dose is taken at least 4 hours, but no later than 16 hours, 
after the first dose. Once the dosing schedule is adjusted, all subsequent doses should be 
taken every 12 hours (±4 hours).
Participants may take the study intervention with or without food. Refer to the IPM for 
additional dosing and administration instructions.
If a dose is delayed, it should be taken as soon as possible, but no later than 4 hours before 
the next scheduled dose. Participants should not double up the next dose of study drug in 
order to “make up” what had been missed. Dosing should be stopped at the end of the 
treatment period (10 doses total). Any remaining tablets and/or capsules at the end of 5 days 
(or 6 days if only one dose was administered on Day 1) should be returned.
6.2. Preparation, Handling, Storage, and Accountability
1. The investigator or designee must confirm that appropriate conditions (eg, 
temperature) have been maintained during transit for all study interventions received 
and any discrepancies are reported and resolved before use of the study intervention. 
2. Only participants enrolled in the study may receive study intervention and only 
authorized site staff may supply, prepare, and/or administer study intervention. 
3. All study interventions must be stored in a secure, environmentally controlled, and 
monitored (manual or automated recording) area in accordance with the labeled 
storage conditions with access limited to the investigator and authorized site staff. At 
a minimum, daily minimum and maximum temperatures for all site storage locations 
must be documented and available upon request. Data for nonworking days must 
indicate the minimum and maximum temperatures since previously documented upon 
return to business.
4. Any excursions from the study intervention label storage conditions should be 
reported to Pfizer upon discovery along with actions taken. The site should actively 
pursue options for returning the study intervention to labeled storage conditions, as 
soon as possible. Once an excursion is identified, the study intervention must be 
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quarantined and not used until Pfizer provides permission to use the study 
intervention. Specific details regarding the excursion definition and information to
report for each excursion will be provided to the site in the IPM.
5. Any storage conditions stated in the SRSD will be superseded by the storage 
conditions stated on the label. Site staff will instruct participants on the proper storage 
requirements for take -home study intervention.
6. Study interventions should be stored in their original containers.
7. The investigator, institution, head of the medical institution (where applicable), or 
authorized site staff is responsible for study intervention accountability, 
reconciliation, and record maintenance (ie, receipt, reconciliation, and final 
disposition records), such as the IPAL or sponsor-approved equivalent. All study 
interventions will be accounted for using a study intervention accountability 
form/record. All study intervention that is taken home by the participant, both used 
and unused, must be returned to the investigator by the participant. Returned study 
intervention must not be redispensed to the participants.
8. Further guidance and information for the final disposition of unused study 
interventions are provided in the IPM. All destruction must be adequately 
documented. If destruction is authorized to take place at the investigator site, the 
investigator must ensure that the materials are destroyed in compliance with 
applicable environmental regulations, institutional policy, and any special instructions 
provided by Pfizer.
Upon identification of a product complaint, notify the sponsor within 1 business day of 
discovery as described in the IPM.
6.2.1. Preparation and Dispensing
A qualified staff member will dispense the study intervention using unique container 
numbers via an IRT system in the bottles provided, in quantities appropriate according to the 
SoA. A second staff member will verify the dispensing. The participant should be instructed 
to maintain the product in the bottles provided throughout the course of dosing.
Study intervention and placebo will be dispensed by qualified blinded site personnel
according to the IP manual. The study intervention will be administered in a blinded fashion
to the participants.
6.3. Assignment to Study Intervention
Allocation of participants to treatment groups will proceed through the use of an IRT system. 
The site personnel (study coordinator or specified designee) will be required to enter or select 
information including but not limited to the user’s ID and password, the protocol number, 
and the participant number. The site personnel will then be provided with a randomization 
number corresponding to the assigned treatment group, and DU or container number(s) when 
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study intervention is being supplied via the IRT system. The IRT system will provide a 
confirmation report containing the participant number, randomization number, and DU or 
container number assigned. The confirmation report must be stored in the site’s files.
Study intervention will be dispensed at the study visits summarized in the SoA.
The study -specific IRT reference manual and IPM will provide the contact information and 
further details on the use of the IRT system.
Returned study intervention must not be redispensed to the study participants.
6.4. Blinding
This is a double-blind study.
6.4.1. Blinding of Participants
Participants and their caregivers will be blinded to their assigned study intervention.
6.4.2. Blinding of Site Personnel
Investigators and other site staff will be blinded to participants’ assigned study intervention. 
Participants will be assigned to receive study intervention according to the assigned treatment 
group from the randomization scheme. Investigators will remain blinded to each participant’s 
assigned study intervention throughout the course of the study.
In the event of a Quality Assurance audit, the auditor(s) will be allowed access to unblinded 
study intervention records at the site(s) to verify that randomization/dispensing has been done 
accurately.
6.4.3. Blinding of the Sponsor
Sponsor staff will be blinded to participants’ assigned study intervention, except for sponsor 
staff involved in the assignment or distribution of study intervention. Sponsor staff who are 
not directly involved with the conduct of this study will prepare analyses and documentation 
containing unblinded data while the study is ongoing to support interactions with the IRC. 
The study will be unblinded after all participants complete the Day 33 visit (or ET prior to 
Day 33 visit) and analyses through Day 33, including the primary efficacy endpoint analyses, 
will be conducted. Details of the timing of unblinding will be outlined in the Unblinding 
Plan.
6.4.4. Breaking the Blind
The IRT will be programmed with blind-breaking instructions. In case of an emergency, the 
investigator has the sole responsibility for determining if unblinding of a participant’s 
treatment assignment is warranted. Participant safety must always be the first consideration 
in making such a determination. If the investigator decides that unblinding is warranted, the 
investigator should make every effort to contact the study medical monitor prior to 
unblinding a participant’s treatment assignment unless this could delay further management 
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of the participant. If a participant’s treatment assignment is unblinded, the sponsor must be 
notified within 24 hours after breaking the blind. The date and reason that the blind was 
broken must be recorded in the source documentation and CRF.
6.5. Study Intervention Compliance
Participants will use a participant-completed dosing diary to record the date and time of their 
study intervention dosing, and will be educated at the time of first dose.
Site personnel will review the participant-completed dosing diary at in person visits (Day 3 
and Day 5) and during an (optional) phone call on Day 2 and Day 4, during the study 
intervention period, preferably after the participant has self-administered the morning dose of 
the study intervention. If any noncompliance with dosing is suspected, site personnel will 
remind the participant of the relevant study procedures and/or entering the information in the 
diary as applicable.
When participants are dosed at the site, they will receive study intervention directly from the 
investigator or designee, under medical supervision. The date and time of each dose 
administered in the clinic will be recorded by the participant in the study intervention log. 
The dose of study intervention and study participant identification will be confirmed at the 
time of dosing by a member of the study site staff other than the person administering the 
study intervention.
When participants self-administer study intervention(s) at home, compliance with study 
intervention will be assessed at each visit. Compliance will be assessed by direct questioning 
and counting returned tablets/capsules during the site visits and documented in the source 
documents and CRF. Deviation(s) from the prescribed dosage regimen should be recorded.
A record of the number of PF-07817883 tablets dispensed to and taken by each participant 
must be maintained and reconciled with study intervention and compliance records.
The following noncompliance cases will be considered medication errors (see Section 
8.4.10).
!
Participants interrupting study intervention for 2 consecutive doses;
!
Participants who have an overall study intervention compliance <80% or >115%.
In addition to the above listed-medication errors, any deviation from protocol-specified
dosing (eg, missed single dose or partial dose) should be recorded as a protocol deviation and
the investigator or designee is to counsel the participant/guardian and ensure steps are taken
to improve compliance.
6.6. Dose Modification
Dose modification for PF-07817883 is not allowed.
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6.7. Continued Access to Study Intervention After the End of the Study
No study intervention will be provided to participants at the end of their study participation.
It is expected that participants will be treated as required with standard-of-care treatments, as 
advised by their usual care physician.
6.8. Treatment of Overdose
For this study, a dose of >12 tablets of “PF-07817883 300 mg or placebo” or >36 tablets of 
“PF-07817883 100 mg or placebo”, or any combination of these tablets achieving maximum 
nominal dose of 
 mg within a 24-hour time period, will be considered an overdose.
There is no specific treatment for an overdose.
In the event of an overdose, the investigator should:
1. Contact the study medical monitor within 24 hours.
2. Closely monitor the participant for any AEs/SAEs and laboratory abnormalities as 
medically appropriate and at least until the next scheduled follow-up.
3. Document the quantity of the excess dose as well as the duration of the overdose in 
the CRF.
4. Overdose is reportable to Pfizer Safety only when associated with an SAE.
5. Obtain a blood sample for PK analysis within 1 day from the date of the last dose of 
study intervention if requested by the study medical monitor (determined on a case by
case basis).
Decisions regarding dose interruptions or modifications will be made by the investigator in 
consultation with the study medical monitor as needed based on the clinical evaluation of the 
participant.
6.9. Prior and Concomitant Therapy
Prior Therapy
Use of an antiviral or mAb therapy for the treatment of COVID-19 within 30 days or 5 half-
lives (whichever is longer) prior to screening is prohibited.
Current or previous administration with an investigational product (drug or vaccine) within 
30 days (or as determined by the local requirement) or 5 half-lives preceding the first dose of 
study intervention used in this study (whichever is longer) is prohibited.
All prescription and over-the-counter medications including vaccines taken by the participant 
within 30 days before study entry (considered prior treatment) will be recorded. Concomitant 
therapies will be collected through the Day 33 visit.
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Permitted During the Study
All participants may receive supportive therapy for COVID-19, in addition to study 
intervention, unless listed as prohibited medication (see Appendix 9) or as defined in Section 
5.2. Supportive therapy for symptom management may include antipyretics, analgesics,
antitussives and anti-emetics.
All participants may receive locally available mAb treatment, direct-acting antiviral 
treatment for SARS-CoV-2 (eg, remdesivir, molnupiravir), or convalescent COVID-19 
plasma treatment for COVID-19 during the study period after enrollment per investigator 
judgement. If the participant needs to receive a direct-acting SARS-CoV-2 antiviral during 
drug dosing period, study drug (PF-07817883 or placebo) should be discontinued (refer to 
Section 7.1).
Prohibited During the Study
If participants require treatment with another antiviral as part of SoC, they will be able to do 
so, with the exception of PAXLOVID which is contraindicated to be administered 
concurrently with the study intervention due to DDI risk. The concomitant use of 
PAXLOVID is not permitted due to overlapping MOA and the ritonavir component may 
increase plasma concentrations of PF-07817883. If the participant needs to receive a direct-
acting SARS-CoV-2 antiviral during drug dosing period, study drug (PF-07817883 or 
placebo) should be discontinued (refer to Section 7.1). COVID-19 vaccinations are permitted 
after the Day 33 visit.
PF-07817883 is primarily metabolized by CYP3A4. Therefore, concomitant use of any 
medications or substances that are moderate to strong inducers or inhibitors of CYP3A4 are 
prohibited within 28 days or 5 half-lives (whichever is longer) prior to dosing of study 
intervention and during study treatment.
A non-exhaustive list of prohibited and precautionary medications is provided in Appendix 9.
If a medication is not listed, it should not automatically be assumed it is safe to co-
administer. Appropriately qualified site staff will review all concomitant medications before 
the first dose of study intervention is administered to determine if they are strong inducers of
CYP3A4 and thus should be prohibited.
6.9.1. Rescue Medicine
Standard medical supportive care may be provided to manage AEs.
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7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL
7.1. Discontinuation of Study Intervention
It may be necessary for a participant to permanently discontinue study intervention. Reasons 
for permanent discontinuation of study intervention include the following:
!
AE of Grade 3 severity or greater and considered by the investigator to be related to 
study intervention;
!
SAE considered by the investigator to be related to study intervention;
!
Requirement for prohibited concomitant medication;
!
Death;
!
Pregnancy;
!
Study terminated by sponsor;
!
Withdrawal by participant or legally authorized representative;
!
Miss more than 2 consecutive doses of study intervention.
!
If post-screening eGFR is <30 mL/min/1.73m2 the participant will be instructed to 
discontinue any remaining study intervention doses as soon as study staff become 
aware of the eGFR results.
!
Receipt of locally available concomitant, non-prohibited, direct-acting antiviral 
therapy for SARS-CoV-2.
In the event a participant is hospitalized, study intervention may continue to be administered, 
as feasible, and based on medical judgement of the investigator.
Discontinuation of study intervention does not represent withdrawal from the study. If study 
intervention is permanently discontinued, the participant should remain in the study to be 
evaluated for all subsequent scheduled assessments. See the SoA for data to be collected at 
the time of discontinuation of study intervention and follow-up for any further evaluations 
that need to be completed.
In the event of discontinuation of study intervention, it must be documented on the 
appropriate CRF/in the medical records whether the participant is discontinuing further 
receipt of study intervention or also from study procedures, further study follow-up, and/or 
future collection of additional information.
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7.1.1. Potential Cases of Acute Kidney Injury
Participants exposed to IMP demonstrating transient or sustained increase in Screat (with 
decrease in Screat-based eGFR or eCrCL require expedited evaluation to differentiate AKI 
from DICI. DICI is defined as transporter-mediated effect related to altered renal tubular 
creatinine handling without histological injury.
Differentiating Acute Kidney Injury from DICI: 
AKI may be due to one or more types of injury, including DIKI. Differentiation of DIKI 
from other causes of AKI and from DICI may require clinical, radiographic, histopathologic, 
and laboratory assessments, as well as nephrology consultation.
Both AKI (including DIKI) and DICI are associated with (i) confirmed Screat increase 
≥0.3 mg/dL (≥26.5 μmol/L) within 48 hours OR (ii) confirmed Screat increase ≥1.5 times 
baseline (known or suspected to have occurred within the prior 7 days). 
Only AKI (including DIKI) is associated with 
!
(i) simultaneous, confirmed serum cystatin C (Scys) increase and confirmed Screat 
increase OR (ii) confirmed albuminuria increase (see Appendix 7 for Grades A1 to A3 
quantitation) OR (iii) urine volume <0.5 mL/kg/h for 6 consecutive hours.  
!
AKI is associated with decrease in Screat-based eGFR and combined Screat-Scys-based 
eGFR (when available).
Regardless of the presence or absence of increase in Screat, DIKI and other causes of AKI
may be suspected if either there is (i) new-onset or worsening albuminuria or proteinuria are 
detected or (ii) urine volume (if measured) is <0.5 mL/kg/h for 6 consecutive hours.
Only DICI is associated with:
!
Confirmed Screat increase without confirmed increase in reflex Scys AND confirmed 
Screat-based eGFR decrease without confirmed combined Screat-Scys-based eGFR 
decrease.
The participant should return to the site for evaluation as soon as possible, preferably within 
48 hours of awareness of the abnormal results. Evaluation should include physical 
examination, laboratory tests, detailed medical and surgical history, review of all medications 
(including recreational drugs and supplements [herbal]), family history, sexual history, travel 
history, blood transfusion, and potential occupational exposure to chemicals. If appropriate, 
nephrology consultation may be recommended to facilitate differentiation of renal 
parenchymal disease, pre-renal azotemia, and post-renal obstruction. All confirmed cases of 
clinically relevant decrease in kidney function should be considered potential cases of DIKI 
if no other reason for the kidney function abnormalities has been found.
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7.1.2. Liver Injury
Please refer to Appendix 6 for suggested actions and follow-up assessments.
7.1.3. ECG Changes
A participant who meets either bulleted criteria based on the average of triplicate ECG 
readings will be withdrawn from the study intervention. 
!
QTcF >500 ms;
!
Change from baseline: QTcF >60 ms and QTcF > 450 ms.
Please refer to Section 8.3.5 for suggested actions and follow up assessments. If a clinically 
significant finding is identified (including, but not limited to, changes from baseline in QTcF
after enrollment), the investigator or qualified designee will determine if the participant can 
continue in the study and if any change in participant management is needed. This review of 
the ECG printed at the time of collection must be documented. Any new clinically relevant 
finding should be reported as an AE.
7.2. Participant Discontinuation/Withdrawal From the Study
A participant may withdraw from the study at any time at their own request. Reasons for 
discontinuation from the study include the following:
!
Refused further study procedures;
!
Lost to follow-up;
!
Death;
!
Study terminated by sponsor;
!
Investigator’s decision;
!
Pregnancy.
At the time of discontinuing from the study, if possible, an early discontinuation visit should 
be conducted. See the SoA for assessments to be collected at the time of study 
discontinuation and follow-up and for any further evaluations that need to be completed.
The early discontinuation visit applies only to participants who are enrolled/randomized and 
then are prematurely withdrawn from the study. Participants should be questioned regarding 
their reason for withdrawal.
If a participant withdraws from the study, they may request destruction of any remaining 
samples taken and not tested, and the investigator must document any such requests in the 
site study records and notify the sponsor accordingly.
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If the participant withdraws from the study and also withdraws consent (see Section 7.2.1) 
for disclosure of future information, no further evaluations will be performed and no 
additional data will be collected. The sponsor may retain and continue to use any data 
collected before such withdrawal of consent.
7.2.1. Withdrawal of Consent
Participants who request to discontinue receipt of study intervention will remain in the study 
and must continue to be followed for protocol-specified follow-up procedures. The only 
exception to this is when a participant specifically withdraws consent for any further contact 
with them or persons previously authorized by the participant to provide this information. 
Participants should notify the investigator in writing of the decision to withdraw consent 
from future follow-up, whenever possible. The withdrawal of consent should be explained in 
detail in the medical records by the investigator, as to whether the withdrawal is only from 
further receipt of study intervention or also from study procedures and/or posttreatment study 
follow-up, and entered on the appropriate CRF page. In the event that vital status (whether 
the participant is alive or dead) is being measured, publicly available information should be 
used to determine vital status only as appropriately directed in accordance with local law.
7.3. Lost to Follow-Up 
A participant will be considered lost to follow-up if the participant repeatedly fails to return 
for scheduled visits and is unable to be contacted by the study site.
The following actions must be taken if a participant fails to return to the clinic for a required 
study visit:
!
The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible. Counsel the participant on the importance of maintaining the 
assigned visit schedule, and ascertain whether the participant wishes to and/or should 
continue in the study;
!
Before a participant is deemed lost to follow-up, the investigator or designee must 
make every effort to regain contact with the participant (where possible, 3 telephone 
calls and, if necessary, a certified letter to the participant’s last known mailing 
address or local equivalent methods). These contact attempts should be documented 
in the participant’s medical record;
!
Should the participant continue to be unreachable, the participant will be considered 
to have withdrawn from the study. 
8. STUDY ASSESSMENTS AND PROCEDURES
8.1. Administrative and Baseline Procedures
The investigator (or an appropriate delegate at the investigator site) must obtain a signed and 
dated ICD before performing any study-specific procedures.
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Study procedures and their timing are summarized in the SoA. Protocol waivers or 
exemptions are not allowed.
Safety issues should be discussed with the sponsor immediately upon occurrence or 
awareness to determine whether the participant should continue or discontinue study 
intervention.
Adherence to the study design requirements, including those specified in the SoA, is essential 
and required for study conduct.
All screening evaluations must be completed and reviewed to confirm that potential 
participants meet all eligibility criteria. The investigator will maintain a screening log to 
record details of all participants screened and to confirm eligibility or record reasons for 
screening failure, as applicable.
Procedures conducted as part of the participant’s routine clinical management (eg, blood 
count) and obtained before signing of the ICD may be utilized for screening or baseline 
purposes provided the procedures met the protocol-specified criteria and were performed 
within the time frame defined in the SoA.
In the event a participant is hospitalized, study assessments should be performed as feasible. 
Procedures not performed due to hospitalizations would not be considered protocol 
deviations.
Every effort should be made to ensure that protocol-required tests and procedures are 
completed as described. However, it is anticipated that from time to time there may be 
circumstances outside the control of the investigator that make it unfeasible to perform the 
test. In these cases, the investigator must take all steps necessary to ensure the safety and 
well-being of the participant. When a protocol-required test cannot be performed, the 
investigator will document the reason for the missed test and any corrective and preventive 
actions that they have taken to ensure that required processes are adhered to as soon as 
possible. The study team must be informed of these incidents in a timely manner.
For samples being collected and shipped, detailed collection, processing, storage, and 
shipment instructions and contact information will be provided to the investigator site prior 
to initiation of the study.
The total blood sampling volume for individual participants in this study is approximately 
240 mL. The actual collection times of blood sampling may change. Additional blood 
samples may be taken for safety assessments at times specified by Pfizer, provided the total 
volume taken during the study does not exceed 550 mL during any period of 56 consecutive 
days.
8.1.1. Secondary Contacts
The investigator will collect contact information for at least 2 individuals who can be 
contacted if the participant cannot be reached after multiple attempts (repeat/update as
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needed) at the times indicated on the SoA. Secondary contacts may be used to determine if a 
participant is lost to follow-up and/or vital status check (whether the participant is alive or 
dead).
8.1.2. Telehealth Visits
Telehealth visits may be used to assess participant safety and collect data points. Telehealth 
includes the exchange of healthcare information and services via telecommunication 
technologies (eg, audio, video, videoconferencing software) remotely, allowing the 
participant and the investigator to communicate on aspects of clinical care, including medical 
advice, reminders, education, and safety monitoring. The following assessments must be 
performed during a telehealth visit (see the SoA):
!
Review and record study intervention(s), including compliance and missed doses.
!
Review and record any AEs and SAEs since the last contact. Refer to Section 8.4.
!
Review and record any new concomitant medications or changes in concomitant 
medications since the last contact.
!
Review and record contraceptive method and results of pregnancy testing. Confirm 
that the participant is adhering to the contraception method(s) required in the 
protocol. Refer to Appendix 4.
!
Confirm the participant has completed the COVID-19 signs and symptoms eDiary 
assessments.
Study participants must be reminded to promptly notify site staff about any change in their 
health status.
Day 33 and ET visits may be conducted by telehealth as outlined in the SoA, and if needed
may be conducted in person at the discretion of the investigator. If a NP sample needs to be 
collected on Day 33, this must be an in person visit at the site. If ET occurs prior to Day 21, 
this visit must also be an in person visit.
8.2. Efficacy Assessments
8.2.1. Participant Diary
Participants will be provided an electronic handheld device or will use their own device to 
record daily COVID-19 signs and symptoms, and other PRO assessments in the study diary.
Participants will receive daily reminders to complete entries on their own as specified in the 
SoA. The diary should be completed at approximately the same time every day. Staff will 
review the participant’s study diary online as specified in the SoA.
The diary allows recording of these assessments only within a fixed time window 
(eg, 24 hours), thus providing an accurate representation of the participant’s experience at 
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that time. The participant is able to make revisions to incorrect entries before pressing the 
save or submit button. In the event that a participant becomes aware of an error in data after 
the entry is saved, a change to the diary data may only be made by the investigator 
submitting a data clarification form. Data reported in the participant diary will be transferred 
electronically to a third-party vendor, where they will be available for review by investigators 
and the sponsor or delegate at all times via an internet-based portal.
8.2.2. COVID-19-Related Medical Visit Details
Details of participants’ COVID-19-related medical visits (ie, hospitalization, practitioner’s
office, home healthcare services, telemedicine, urgent care, emergency room ≤24 hours, 
extended care facility stay) will be collected during study visits, including level of care (eg,
ICU status), dates of utilization, and admission and discharge dates, as applicable. Whether 
medical visits are considered COVID-19-related will be determined by the investigator, for 
all outpatient and inpatients visits.
Hospitalization is defined as >24 hours of acute care, in a hospital or similar acute care 
facility, including Emergency Rooms or temporary facilities instituted to address medical 
needs of those with severe COVID-19 during the COVID-19 pandemic. This includes 
specialized acute medical care unit within an assisted living facility or nursing home. This 
does not include hospitalization for the purposes of public health and/or clinical trial 
execution.
8.2.3. Daily Signs and Symptoms of COVID-19
On Day 1, participants will complete the study diary before receiving study intervention. 
Participant assessment of COVID-19-related symptoms should be recorded at approximately 
the same time each day as specified in the SoA and described in Section 8.2.1.
COVID-19-related symptoms will be evaluated in accordance with FDA guidelines 
(Appendix 10).13 Participants will record a daily severity rating of their symptom severity 
over the past 24 hours based on a 4-point scale in which 0 is reported if no symptoms were 
present; 1 if mild; 2 if moderate; and 3 if severe.
Vomiting and diarrhea will each be rated on a 4-point frequency scale where 0 is reported for 
no occurrence, 1 for 1 to 2 times, 2 for 3 to 4 times, and 3 for 5 or greater. 
Sense of smell and sense of taste will each be rated on a 3-point Likert scale where 0 is 
reported if the sense of smell/taste was the same as usual, 1 if the sense of smell/taste was 
less than usual, and 2 for no sense of smell/taste.
Five additional COVID-19 daily symptom diary items are included in the revised study 
diary: 1) Shortness of breath (difficulty breathing) while resting, 2) Shortness of breath 
(difficulty breathing) while physically active*, 3) Chest pain, 4) Low energy or tiredness 
after physical activity*, and 5) Difficulty concentrating. The response options for these 
questions are: None = 0, Mild = 1, Moderate = 2, or Severe = 3, and *I did not perform 
physical activity = 0 where applicable.
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8.2.4. Oxygen Support Details 
Type of oxygen support (eg, oxygen supplementation received at home, mechanical 
ventilation received in hospital) will be collected.
8.2.5. Global Impression Questions
Three questions will be included in the ePRO to assess patient-reported global impression 
items a) return to usual health; b) return to usual activities; and c) overall COVID-19-related 
symptoms:13
!
In the past 24 hours, have you returned to your usual health (before your COVID-19 
illness)? Yes or No.
!
In the past 24 hours, have you returned to your usual activities (before your COVID-
19 illness)? Yes or No.
!
In the past 24 hours, what was the severity of your overall COVID-19-related 
symptoms at their worst? None, Mild, Moderate, or Severe.
The following three anchor items will also be included in the ePRO:
!
Fatigue:
Please choose the response below that best describes the severity of your physical 
fatigue (ie, weakness, tiredness, lack of energy) over the past 7 days: None, Mild, 
Moderate, Severe or Very severe.
!
Shortness of Breath:
Please choose the response below that best describes the severity of your shortness of 
breath (difficulty breathing) over the past 7 days: None, Mild, Moderate, Severe or 
Very severe.
!
Cognitive Function:
Please choose the response below that best describes the severity of your difficulty 
concentrating over the past 7 days: None, Mild, Moderate, Severe or Very severe.
8.3. Safety Assessments
Planned time points for all safety assessments are provided in the SoA. Unscheduled safety 
measurements may be obtained at any time during the study to assess any perceived safety 
issues.
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8.3.1. Medical History
Medical history in addition to COVID-19 disease history and demographics will be collected 
at screening. Smoking status will be collected. Complete medication history of all 
prescription or nonprescription drugs (including vaccinations), and dietary and herbal 
supplements taken within 30 days prior to the planned first dose will be collected. All 
COVID-19 vaccinations received at any time prior to the planned first dose will also be 
collected.
8.3.2. Height and Weight
Height and weight will also be measured and recorded at screening. Height may be self-
reported.
8.3.3. Targeted Physical Examinations
Physical examinations to be completed before administration of study intervention.
A targeted physical examination will include, at a minimum, cardiopulmonary assessments. 
Investigators should pay special attention to any previously identified or new AE/targeted 
condition that the participant has experienced.
Physical examination findings collected during the study will be considered source data and 
will not be required to be reported, unless otherwise noted. Any untoward physical 
examination findings that are identified during the active collection period and meet the 
definition of an AE or SAE (Appendix 3) must be reported according to the processes in 
Sections 8.4.1 to 8.4.3.
8.3.4. Vital Signs
Any untoward vital sign findings that are identified during the active collection period and 
meet the definition of an AE or SAE (Appendix 3) must be reported according to the 
processes in Sections 8.4.1 to 8.4.3.
Temperature, PR, respiratory rate, oxygen saturation level, and blood pressure will be 
assessed as specified in the SoA.
Blood pressure and PR measurements will be assessed with the participant in the supine or 
seated position with their feet on the floor when possible with a completely automated 
device. It is recommended that the same position should be used for a participant throughout 
the study duration. Manual techniques will be used only if an automated device is not 
available.
Blood pressure and PR measurements should be preceded by at least 5 minutes of rest for the 
participant in a quiet setting without distractions (eg, television, cell phones).
Vital signs are to be taken before blood collection for laboratory tests.
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8.3.4.1. Blood Pressure and Pulse Rate
BP and PR measurements will be assessed with the participant, preferably in the supine or 
seated position with their feet on the floor when possible with a completely automated 
device. It is recommended that the same position should be used for a participant throughout 
the study duration. Manual techniques will be used only if an automated device is not 
available.
8.3.4.2. Temperature and Respiratory Rate
Temperature, and respiratory rate, will be assessed.
8.3.4.3. Oxygen Saturation Level
Oxygen saturation level will be assessed as part of the vital signs assessment.
8.3.5. Electrocardiograms
Standard 12-lead ECGs utilizing limb leads (with a 10-second rhythm strip) should be 
collected at times specified in the SoA section of this protocol using an ECG machine that
automatically calculates the HR and measures PR interval, QT interval, QTcF, and QRS 
complex. If an ECG cannot be obtained on Day 10, it must be collected at Day 14. An ECG 
should be obtained for a participant having an ET visit before Day 14. Alternative lead 
placement methodology using torso leads (eg, Mason-Likar) should not be used given the 
potential risk of discrepancies with ECGs acquired using standard limb lead placement. Post-
dose ECGs should be performed within 30 to 90 minutes post-dose. All scheduled ECGs 
should be performed after the participant has rested quietly for at least 5 minutes in a supine 
position. Triplicate 12-lead ECGs obtained at a minimum at baseline/Day 1, should be 
obtained approximately 2 to 4 minutes apart.
ECG data may be submitted to a central laboratory for measurement. The final ECG report 
from the central laboratory should be maintained in the participant’s source documentation 
and be the final interpretation of the ECG recording. Any clinically significant changes from 
the baseline/Day 1 ECG may potentially be AEs (Appendix 8) and should be evaluated 
further, as clinically warranted.
If a) a post-dose QTcF interval remains ≥60 ms from the baseline and is >450 ms; or b) an 
absolute QTcF value is ≥500 ms for any scheduled ECG for greater than 4 hours (or sooner,
at the discretion of the investigator); or c) QTcF values get progressively longer, the 
participant should undergo continuous ECG monitoring.
A cardiologist may be consulted if QTcF values do not return to less than the criteria listed 
above after 8 hours of monitoring (or sooner, at the discretion of the investigator).
In some cases, it may be appropriate to repeat abnormal ECGs to rule out improper lead 
placement as contributing to the ECG abnormality. It is important that leads be placed in the 
same positions each time in order to achieve precise ECG recordings. If a machine-read QTc 
value is prolonged, as defined above, repeat measurements may not be necessary if a 
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qualified medical provider’s interpretation determines that the QTcF values are in the 
acceptable range.
ECG values of potential clinical concern are listed in Appendix 8.
8.3.6. Clinical Safety Laboratory Assessments
Day 1 safety laboratory assessments must be collected prior to first dose of study 
intervention.
See Appendix 2 for the list of clinical safety laboratory tests to be performed and the SoA for
the timing and frequency. All protocol required laboratory assessments, as defined in 
Appendix 2, must be conducted in accordance with the laboratory manual and the SoA.
Unscheduled clinical laboratory measurements may be obtained at any time during the study 
to assess any perceived safety issues.
Laboratory safety parameters will be graded according to the DAIDS Table for Grading the 
Severity of Adult and Pediatric Adverse Events14, version 2.1. The investigator must review 
the laboratory report, document this review, and record any clinically significant changes 
occurring during the study in the AE section of the CRF. Clinically significant abnormal 
laboratory test findings are those that are not associated with the underlying disease, unless 
judged by the investigator to be more severe than expected for the participant's condition.
All laboratory tests with values considered clinically significant and abnormal during 
participation in the study or within 28 days after the last dose of study intervention should be 
repeated until the values return to normal or baseline or are no longer considered clinically 
significant by the investigator or study medical monitor.
If such values do not return to normal/baseline within a period of time judged reasonable by 
the investigator, the etiology should be identified and the sponsor notified.
See Appendix 6 for suggested actions and follow-up assessments in the event of potential 
DILI.
See Appendix 7 for instructions for laboratory testing to monitor kidney function and 
reporting laboratory test abnormalities.
8.3.6.1. Alternative Facilities for Clinical Safety Laboratory Assessment
Not applicable.
8.3.7. Pregnancy Testing
A serum or urine pregnancy test is required at screening. Following screening, pregnancy 
tests may be urine or serum tests, and must have a sensitivity of at least 25 mIU/mL. 
Pregnancy tests will be performed in WOCBP at the times listed in the SoA. Following a 
negative pregnancy test result at screening, appropriate contraception must be commenced 
and a second negative pregnancy test result will be required at the baseline visit prior to the 
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participant’s receiving the study intervention. Pregnancy tests will also be done whenever 1 
menstrual cycle is missed during the active treatment period (or when potential pregnancy is 
otherwise suspected) and at the end of the study. Pregnancy tests may also be repeated if 
requested by IRBs/ECs or if required by local regulations. If a urine test cannot be confirmed 
as negative (eg, an ambiguous result), a serum pregnancy test is required. In such cases, the 
participant must be excluded if the serum pregnancy result is positive.
8.3.7.1. At-Home Pregnancy Testing
If a participant requiring pregnancy testing cannot visit a local laboratory, a home urine 
pregnancy testing kit with a sensitivity of at least 25 mIU/mL may be used by the participant 
to perform the test at home, if compliant with local regulatory requirements. The pregnancy 
test outcome should be documented in the participant’s source documents/medical records 
and relevant data recorded on the CRF. If the pregnancy test is positive, the EDP should be 
reported (Section 8.4.5.1). Confirm that the participant is adhering to the contraception 
method(s) required in the protocol.
8.3.7.2. Evaluation for Menopause
FSH is to be performed locally in female participants <60 years of age at screening who are 
not using hormonal contraception or hormonal replacement therapy, to confirm 
postmenopausal status. Female participants age 50 to 60 years with no menses for 12 months 
do not need FSH testing to be performed to confirm postmenopausal status.
A participant may be screened in the study prior to the test result being available as long as 
the FSH test result confirms postmenopausal status prior to dosing.
8.3.8. Adjunctive Therapeutic Procedures
Adjunctive therapeutic procedures will be recorded as specified in the SoA. Therapeutic 
procedures such as imaging, supplemental oxygen support (eg, CPAP) and transfusions
should be recorded.
8.4. Adverse Events, Serious Adverse Events, and Other Safety Reporting
The definitions of an AE and an SAE can be found in Appendix 3.
AEs may arise from symptoms or other complaints reported to the investigator by the 
participant (or, when appropriate, by a caregiver, surrogate, or the participant's legally 
authorized representative), or they may arise from clinical findings of the investigator or 
other healthcare providers (clinical signs, test results, etc).
The investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE or SAE and remain responsible to pursue 
and obtain adequate information both to determine the outcome and to assess whether the 
event meets the criteria for classification as an SAE or caused the participant to discontinue 
the study intervention (see Section 7.1).
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During the active collection period as described in Section 8.4.1, each participant will be 
questioned about the occurrence of AEs in a nonleading manner.
In addition, the investigator may be requested by Pfizer Safety to obtain specific follow-up 
information in an expedited fashion.
8.4.1. Time Period and Frequency for Collecting AE and SAE Information
The time period for actively eliciting and collecting AEs and SAEs (“active collection 
period”) for each participant begins from the time the participant provides informed consent, 
which is obtained before undergoing any study-related procedure and/or receiving study 
intervention, through and including a minimum of 28 calendar days, except as indicated 
below, after the last administration of the study intervention.
Follow-up by the investigator continues throughout the active collection period and until the 
AE or SAE or its sequelae resolve or stabilize at a level acceptable to the investigator.
When a clinically important AE remains ongoing at the end of the active collection period, 
follow-up by the investigator continues until the AE or SAE or its sequelae resolve or 
stabilize at a level acceptable to the investigator and Pfizer concurs with that assessment.
For participants who are screen failures, the active collection period ends when screen failure 
status is determined.
If the participant withdraws from the study and also withdraws consent for the collection of 
future information, the active collection period ends when consent is withdrawn.
If a participant permanently discontinues or temporarily discontinues study intervention 
because of an AE or SAE, the AE or SAE must be recorded on the CRF and the SAE 
reported using the CT SAE Report Form.
Investigators are not obligated to actively seek information on AEs or SAEs after the 
participant has concluded study participation. However, if the investigator learns of any SAE, 
including a death, at any time after a participant has completed the study, and they consider 
the event to be reasonably related to the study intervention, the investigator must promptly 
report the SAE to Pfizer using the CT SAE Report Form.
8.4.1.1. Reporting SAEs to Pfizer Safety
All SAEs occurring in a participant during the active collection period as described in
Section 8.4.1 are reported to Pfizer Safety on the CT SAE Report Form immediately upon 
awareness and under no circumstance should this exceed 24 hours, as indicated in 
Appendix 3. The investigator will submit any updated SAE data to the sponsor within 
24 hours of its being available.
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8.4.1.2. Recording Nonserious AEs and SAEs on the CRF
All nonserious AEs and SAEs occurring in a participant during the active collection period, 
which begins after obtaining informed consent as described in Section 8.4.1, will be recorded 
on the AE section of the CRF.
The investigator is to record on the CRF all directly observed and all spontaneously reported 
AEs and SAEs reported by the participant.
As part of ongoing safety reviews conducted by the sponsor, any nonserious AE that is 
determined by the sponsor to be serious will be reported by the sponsor as an SAE. To assist 
in the determination of case seriousness, further information may be requested from the 
investigator to provide clarity and understanding of the event in the context of the clinical 
study.
Reporting of AEs and SAEs for participants who fail screening are subject to the CRF 
requirements as described in Section 5.4.
8.4.2. Method of Detecting AEs and SAEs
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Appendix 3.
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
nonleading verbal questioning of the participant is the preferred method to inquire about 
AE occurrences.
8.4.3. Follow-Up of AEs and SAEs
After the initial AE or SAE report, the investigator is required to proactively follow each 
participant at subsequent visits/contacts. For each event, the investigator must pursue and 
obtain adequate information until resolution, stabilization, the event is otherwise explained, 
or the participant is lost to follow-up (as defined in Section 7.3).
In general, follow-up information will include a description of the event in sufficient detail to 
allow for a complete medical assessment of the case and independent determination of 
possible causality. Any information relevant to the event, such as concomitant medications 
and illnesses, must be provided. In the case of a participant death, a summary of available 
autopsy findings must be submitted as soon as possible to Pfizer Safety. 
Further information on follow-up procedures is provided in Appendix 3.
8.4.4. Regulatory Reporting Requirements for SAEs
Prompt notification by the investigator to the sponsor of an SAE is essential so that legal 
obligations and ethical responsibilities toward the safety of participants and the safety of a 
study intervention under clinical investigation are met.
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The sponsor has a legal responsibility to notify both the local regulatory authority and other 
regulatory agencies about the safety of a study intervention under clinical investigation. The 
sponsor will comply with country-specific regulatory requirements relating to safety 
reporting to the regulatory authority, IRBs/ECs, and investigators.
Investigator safety reports must be prepared for SUSARs according to local regulatory 
requirements and sponsor policy and forwarded to investigators as necessary.
An investigator who receives SUSARs or other specific safety information (eg, summary or 
listing of SAEs) from the sponsor will review and then file it along with the SRSD(s) for the 
study and will notify the IRB/EC, if appropriate according to local requirements.
8.4.5. Environmental Exposure, Exposure During Pregnancy or Breastfeeding, and 
Occupational Exposure
Environmental exposure occurs when a person not enrolled in the study as a participant 
receives unplanned direct contact with or exposure to the study intervention. Such exposure 
may or may not lead to the occurrence of an AE or SAE. Persons at risk for environmental 
exposure include healthcare providers, family members, and others who may be exposed. An 
environmental exposure may include EDP, EDB, and occupational exposure.
Any such exposures to the study intervention under study are reportable to Pfizer Safety 
within 24 hours of investigator awareness.
8.4.5.1. Exposure During Pregnancy
An EDP occurs if:
!
A female participant is found to be pregnant while receiving or after discontinuing 
study intervention.
!
A male participant who is receiving or has discontinued study intervention 
inseminates a female partner.
!
A female nonparticipant is found to be pregnant while being exposed or having been 
exposed to study intervention because of environmental exposure. Below are 
examples of environmental EDP:
!
A female family member or healthcare provider reports that she is pregnant after 
having been exposed to the study intervention by ingestion.
!
A male family member or healthcare provider who has been exposed to the study 
intervention by ingestion then inseminates his female partner prior to or around 
the time of conception.
The investigator must report EDP to Pfizer Safety within 24 hours of the investigator’s 
awareness, irrespective of whether an SAE has occurred. The initial information submitted 
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should include the anticipated date of delivery (see below for information related to 
termination of pregnancy). 
!
If EDP occurs in a participant/participant’s partner, the investigator must report this 
information to Pfizer Safety on the CT SAE Report Form and an EDP Supplemental 
Form, regardless of whether an SAE has occurred. Details of the pregnancy will be 
collected after the start of study intervention and until a minimum of 28 calendar days
after the last administration of study intervention.
!
If EDP occurs in the setting of environmental exposure, the investigator must report 
information to Pfizer Safety using the CT SAE Report Form and EDP Supplemental 
Form. Since the exposure information does not pertain to the participant enrolled in 
the study, the information is not recorded on a CRF; however, a copy of the 
completed CT SAE Report Form is maintained in the investigator site file.
Follow-up is conducted to obtain general information on the pregnancy and its outcome for 
all EDP reports with an unknown outcome. The investigator will follow the pregnancy until 
completion (or until pregnancy termination) and notify Pfizer Safety of the outcome as a 
follow-up to the initial EDP Supplemental Form. In the case of a live birth, the structural 
integrity of the neonate can be assessed at the time of birth. In the event of a termination, the 
reason(s) for termination should be specified and, if clinically possible, the structural 
integrity of the terminated fetus should be assessed by gross visual inspection (unless
preprocedure test findings are conclusive for a congenital anomaly and the findings are 
reported).
Abnormal pregnancy outcomes are considered SAEs. If the outcome of the pregnancy meets 
the criteria for an SAE (ie, ectopic pregnancy, spontaneous abortion, intrauterine fetal 
demise, neonatal death, or congenital anomaly in a live-born baby, a terminated fetus, an 
intrauterine fetal demise, or a neonatal death), the investigator should follow the procedures 
for reporting SAEs. Additional information about pregnancy outcomes that are reported to 
Pfizer Safety as SAEs follows: 
!
Spontaneous abortion including miscarriage and missed abortion should be reported 
as an SAE;
!
Neonatal deaths that occur within 1 month of birth should be reported, without regard 
to causality, as SAEs. In addition, infant deaths after 1 month should be reported as 
SAEs when the investigator assesses the infant death as related or possibly related to 
exposure to the study intervention. 
Additional information regarding the EDP may be requested by the sponsor. Further 
follow-up of birth outcomes will be handled on a case-by-case basis (eg, follow-up on 
preterm infants to identify developmental delays). In the case of paternal exposure, the 
investigator will provide the participant with the Pregnant Partner Release of Information 
Form to deliver to his partner. The investigator must document in the source documents that 
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the participant was given the Pregnant Partner Release of Information Form to provide to his 
partner.
8.4.5.2. Exposure During Breastfeeding
An EDB occurs if:
!
A female participant is found to be breastfeeding while receiving or after
discontinuing study intervention.
!
A female nonparticipant is found to be breastfeeding while being exposed or having 
been exposed to study intervention (ie, environmental exposure). An example of 
environmental EDB is a female family member or healthcare provider who reports 
that she is breastfeeding after having been exposed to the study intervention by
ingestion.
The investigator must report EDB to Pfizer Safety within 24 hours of the investigator’s 
awareness, irrespective of whether an SAE has occurred. The information must be reported 
using the CT SAE Report Form. When EDB occurs in the setting of environmental exposure, 
the exposure information does not pertain to the participant enrolled in the study, so the 
information is not recorded on a CRF. However, a copy of the completed CT SAE Report 
Form is maintained in the investigator site file.
An EDB report is not created when a Pfizer drug specifically approved for use in 
breastfeeding women (eg, vitamins) is administered in accordance with authorized use. 
However, if the infant experiences an SAE associated with such a drug, the SAE is reported 
together with the EDB.
8.4.5.3. Occupational Exposure
The investigator must report any instance of occupational exposure to Pfizer Safety within 
24 hours of the investigator’s awareness using the CT SAE Report Form, regardless of 
whether there is an associated SAE. Since the information about the occupational exposure
does not pertain to a participant enrolled in the study, the information is not recorded on a 
CRF; however, a copy of the completed CT SAE Report Form must be maintained in the 
investigator site file.
8.4.6. Cardiovascular and Death Events
Not applicable.
8.4.7. Disease-Related Events and/or Disease-Related Outcomes Not Qualifying as AEs 
or SAEs
Not applicable.
8.4.8. Adverse Events of Special Interest
Not applicable.
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8.4.8.1. Lack of Efficacy
The investigator must report signs, symptoms, and/or clinical sequelae resulting from lack of 
efficacy. Lack of efficacy or failure of expected pharmacological action is reportable to Pfizer 
Safety only if associated with an SAE.
8.4.9. Medical Device Deficiencies
Not applicable.
8.4.10. Medication Errors
Medication errors may result from the administration or consumption of the study 
intervention by the wrong participant, or at the wrong time, or at the wrong dosage strength.
Medication errors are recorded and reported as follows:
Recorded on the 
Medication Error Page 
of the CRF
Recorded on the 
Adverse Event Page 
of the CRF
Reported on the CT SAE 
Report Form to Pfizer 
Safety Within 24 Hours of 
Awareness
All (regardless of whether 
associated with an AE)
Any AE or SAE associated 
with the medication error
Only if associated with an 
SAE
Medication errors include:
!
Medication errors involving participant exposure to the study intervention;
!
Potential medication errors or uses outside of what is foreseen in the protocol that do 
or do not involve the study participant.
!
The administration of expired study intervention;
!
The administration of an incorrect study intervention;
!
The administration of an incorrect dosage;
!
The administration of study intervention that has undergone temperature excursion 
from the specified storage range, unless it is determined by the sponsor that the study 
intervention under question is acceptable for use.
!
The administration of study intervention consistent with the medication error 
descriptions in Section 6.5.
Such medication errors occurring to a study participant are to be captured on the medication 
error page of the CRF, which is a specific version of the AE page.
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Whether or not the medication error is accompanied by an AE, as determined by the 
investigator, the medication error is recorded on the medication error page of the CRF and, if 
applicable, any associated AE(s), serious and nonserious, are recorded on the AE page of the 
CRF.
In the event of a medication dosing error, the sponsor should be notified within 24 hours.
Medication errors should be reported to Pfizer Safety within 24 hours on a CT SAE Report 
Form only when associated with an SAE.
8.5. Pharmacokinetics
Blood samples of approximately 4 mL, to provide a minimum of 1.5 mL of plasma, will be 
collected for measurement of plasma concentrations of PF-07817883 as specified in the SoA.
Prior to centrifugation a 0.1 mL portion of the 4 mL of blood collected will be aliquoted for 
the purpose of determining the blood to plasma PF-07817883 concentration ratio at each time 
point as specified in the SoA. In addition, approximately 0.1 mL of blood will be collected 
using a micro-sampling device (TASSO M20) for the measurement of plasma concentrations 
of PF-07817883 at each time point as specified in the SoA. Instructions for the collection and 
handling of biological samples will be provided in the laboratory manual or by the sponsor.
The actual date and time (24-hour clock time) of each sample will be recorded.
The actual times may change, but the number of samples will remain the same. All efforts 
will be made to obtain the samples at the exact nominal time relative to dosing. 
Samples will be used to evaluate the PK of PF-07817883. Each plasma sample will be 
divided into 2 aliquot(s) (1 each for PK, other analyses, etc). Samples collected for analyses 
of PF-07817883 plasma concentration may also be used to evaluate safety or efficacy aspects 
related to concerns arising during or after the study, for metabolite identification and/or 
evaluation of the bioanalytical method, or for other internal exploratory purposes.
Genetic analyses will not be performed on these plasma or whole blood samples unless 
consent for this was included in the informed consent. Participant confidentiality will be 
maintained.
Samples collected for measurement of plasma or whole blood concentrations of 
PF-07817883 will be analyzed using a validated analytical method in compliance with 
applicable SOPs. Potential metabolites may be analyzed with either validated or exploratory 
methods.
The PK samples must be processed and shipped as indicated in the instructions provided to 
the investigator site to maintain sample integrity. Any deviations from the PK sample 
handling procedure (eg, sample collection and processing steps, interim storage or shipping 
conditions), including any actions taken, must be documented and reported to the sponsor. 
On a case-by-case basis, the sponsor may make a determination as to whether sample 
integrity has been compromised.
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Drug concentration information that would unblind the study will not be reported to 
investigator sites or blinded personnel until the study has been unblinded.
Any changes in the timing or addition of time points for any planned study assessments must 
be documented and approved by the relevant study team member and then archived in the 
sponsor and site study files, but will not constitute a protocol amendment. The IRB/EC will 
be informed of any safety issues that require alteration of the safety monitoring scheme or 
amendment of the ICD.
8.6. Genetics
8.6.1. Specified Genetics
Specified genetic analyses are not evaluated in this study.
8.6.2. Retained Research Samples for Genetics
A 4 mL blood sample optimized for DNA isolation Prep D1 will be collected according to the 
SoA, as local regulations and IRBs/ECs allow, and if the participant signs the optional 
consent form.
Retained Research Samples may be used for research related to the study intervention(s) and 
COVID-19. Genes and other analytes (eg, proteins, RNA, nondrug metabolites) may be 
studied using the retained samples. 
See Appendix 5 for information regarding genetic research. Details on processes for 
collection and shipment of these samples can be found in the laboratory manual.
8.7. Biomarkers
Collection of samples for biomarker research is also part of this study. 
The following samples for biomarker research are required and will be collected from all 
participants in this study as specified in the SoA:
!
NP samples will be collected to measure SARS-CoV-2 viral RNA level by RT-PCR.
!
Residual NP viral RNA level samples may be used for SARS-CoV-2 viral 
sequencing.
!
Residual NP viral RNA level samples may be used for SARS-CoV-2 infectivity 
assays and phenotypic analyses.
!
10 mL blood optimized for plasma may be utilized for proteomics and immunologic
studies.
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8.7.1. Rapid Antigen Assessments
Rapid antigen testing for SARS-CoV-2 will be performed at screening as described in the 
SoA. Investigational sites will use test kits that are authorized for use in this study.
Confirmed SARS-CoV-2 infection as determined by RAT using a test kit that is authorized 
by the sponsor in a nasal specimen collected within 2 days prior to randomization is required.
8.7.2. Specified Gene Expression (RNA) Research 
Specified gene expression (RNA) research is not included in this study.
8.7.3. Specified Protein Research 
Blood will be collected for plasma biomarkers as specified in the SoA and may be used for
proteomics and molecular and immunologic studies. Residuals of all samples may be banked 
for future research. Storage and shipping instructions will be in accordance with the 
laboratory manual.
8.7.4. Specified Metabolomic Research
Specified metabolomic research is not included in this study.
8.7.5. Viral RNA Level Assessments
A NP sample will be collected per the SoA, and may be analyzed to measure SARS-CoV-2 
RNA by RT-PCR. At baseline, a NP sample will be collected by the investigational site staff 
to confirm SARS-CoV-2 infection by RT-PCR. This test will not be used to determine study 
eligibility. NP samples will be collected by an HCP during an in-person visit.
If a participant is symptomatic due to COVID-19 infection at the Day 21 visit then a Day 33 
NP sample should be collected.
If COVID-19 symptom worsening or recurrence occurs after completion of the 5-day
treatment with study drug (ie, through Day 33), participants may subsequently attend a site 
for an unscheduled follow-up visit and should have NP sample collected to measure SARS-
CoV-2 RNA levels.
Residual viral RNA level samples may be utilized for viral sequencing to assess the signs of 
viral evolution and evaluation of potential genetic viral variants including but not limited to
3CL gene, SARS-CoV-2 infectivity assays, molecular and phenotypical analysis, including 
host molecular or genetic analysis.
Residuals of all samples may be banked for future research. Storage and shipping instructions
will be in accordance with the laboratory manual.
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8.7.6. Retained Research Samples for Biomarkers
These Retained Research Samples will be collected in this study if the participant signs the 
optional consent form:
!
5 mL whole blood optimized for serum Prep B2.5.
!
2.5 ml whole blood optimized for RNA Prep R1.
Retained Research Samples will be collected in this study as local regulations and IRB/ECs 
allow according to the SoA.
Retained Research Samples may be used for research related to the study intervention(s) and
COVID-19. Genes and other analytes (eg, proteins, RNA, nondrug metabolites) may be
studied using the retained samples.
See Appendix 5 for information regarding genetic research. Details on processes for
collection and shipment of these samples can be found in the laboratory manual.
8.8. Immunogenicity Assessments
Immunogenicity assessments are not applicable to this study.
8.9. Health Economics
Health economics/medical resource utilization and health economics parameters will be 
evaluated in this study (Section 8.2.2 and Section 8.2.3).
9. STATISTICAL CONSIDERATIONS
Detailed methodology for summary and statistical analyses of the data collected in this study 
is outlined here and further detailed in the SAP, which will be maintained by the sponsor. 
The SAP may modify what is outlined in the protocol where appropriate; however, any major 
modifications of the primary endpoint definitions or their analyses will also be reflected in a 
protocol amendment.
9.1. Statistical Hypothesis
The primary hypothesis is to test whether or not there is a difference in mean change of 
SARS-CoV-2 RNA level from baseline to Day 5 between the PF-07817883 dose groups and 
the placebo group using the Bayesian dose-response model (or otherwise as specified in 
Section 9.3.2.2):
Null hypothesis: H0 	
	

 − = 0
Alternative hypothesis: Ha 	
	

 − < 0
Where 	
	

 and  are mean change of SARS-CoV-2 RNA level from 
baseline to Day 5 for each PF-07817883 dose groups and placebo group.
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9.1.1. Estimands
9.1.1.1. Primary Estimand
E1 (primary analysis estimand): The estimand is the difference between the PF-07817883 
dose groups and placebo in mean change from baseline in SARS-CoV-2 RNA level in NP 
samples in the population of non-hospitalized, symptomatic, adult participants with 
COVID-19 who have SARS-CoV-2 RNA level ≥4 log10 copies/mL at baseline. This analysis
will exclude data after use of prohibited COVID-19 medications and study treatment 
discontinuation.
E2 (estimand for supplementary analyses): The estimand is the difference between the 
PF-07817883 dose groups and placebo in mean change from baseline in SARS-CoV-2 RNA 
level in NP samples in the population of non-hospitalized, symptomatic, adult participants 
with COVID-19. This will exclude data after use of prohibited COVID-19 medications and 
study treatment discontinuation.
The E2 estimand will be applied to change from baseline in SARS-CoV-2 RNA level on 
Days 3, 5, 10 and 14 for the supplementary analysis.
Note that for E1 and E2, partial participant data accumulated prior to use of prohibited 
COVID-19 medications or treatment discontinuation is included in the analysis.
9.1.1.2. Secondary Estimands
The E1 estimand will be applied to change from baseline in SARS-CoV-2 RNA level on 
Days 3, 10 and 14.
9.1.2. Multiplicity Adjustment
Not applicable.
9.2. Analysis Sets
For purposes of analysis, the following analysis sets are defined:
Participant Analysis Set
Description
Enrolled 
"Enrolled" means a participant's, or their legally authorized
representative’s, agreement to participate in a clinical 
study following completion of the informed consent 
process and randomization to study intervention. A 
participant will be considered enrolled if the informed 
consent is not withdrawn prior to participating in any study 
activity after screening. Potential participants who are 
screened for the purpose of determining eligibility for the 
study, but do not participate in the study, are not 
considered enrolled, unless otherwise specified by the 
protocol.
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Participant Analysis Set
Description
FAS
All participants randomly assigned to study intervention 
and who take at least 1 dose of study intervention.
Participants will be analyzed according to the study 
intervention to which they were randomized.
SAS
All participants randomly assigned to study intervention
and who take at least 1 dose of study intervention.
Participants will be analyzed according to the product they 
actually received.
PK analysis set
All enrolled participants who received at least 1 dose of 
PF-07817883 and in whom at least 1 concentration value is 
reported.
Defined Analysis Set
Description
MFAS
All participants in the FAS who have SARS-CoV-2 RNA 
level ≥4 log10 copies/mL at baseline.
Participants will be analyzed according to the study 
intervention to which they were randomized.
9.3. Statistical Analyses
The SAP will be developed and finalized before any analyses are performed and will 
describe the analyses and procedures for accounting for missing, unused, and spurious data.
Further analysis details will be included in SAP. This section is a summary of the planned 
statistical analyses of the primary and secondary endpoints.
9.3.1. General Considerations
Descriptive statistics for all efficacy endpoints by treatment group and visit will be provided.
The number of participants screened will be reported. The number of participants 
randomized to the double-blind treatment phase, completing the study drug administration, 
completing the study, and discontinued the study will be summarized from the FAS for each 
treatment group.
Baseline demographic and other characteristics will be tabulated for the FAS and 
summarized by treatment group. Quantitative variables will be described by standard 
descriptive statistics (mean, standard deviation, minimum, and maximum), and qualitative 
variables will be summarized by frequency tables with number and proportion in each 
category (with the corresponding sample sizes).
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For continuous endpoints, an MMRM model will be used to analyze change from baseline 
outcomes. Estimated mean differences between treatments and their respective 80% CI and 
p-values will be calculated.
Binary endpoints will be summarized with the number and percent of participants satisfying 
the endpoint.
For categorical endpoints, proportion of participants for each category will be summarized 
for each treatment group.
For count endpoints, the total number of the events and average number of events will be 
summarized for each treatment group.
Time to event endpoints will be summarized graphically using Kaplan-Meier plots for each 
treatment group. 
9.3.2. Primary Endpoint(s)/Estimand(s) Analysis
9.3.2.1. Definition of Endpoint(s)
The primary efficacy endpoint is the change in SARS-CoV-2 RNA level from baseline to 
Day 5 as measured in NP samples.
9.3.2.2. Main Analytical Approach
The primary analysis will utilize a Bayesian Emax model applied to the estimates from the 
MMRM analysis. 
Change from baseline in SARS-CoV-2 RNA level at Day 5 will first be analyzed using 
Estimand 1 and MMRM model (as per Section 9.3.1). The MMRM model will be fitted to 
the change from baseline at all post-treatment timepoints up to Day 5 using MFAS with fixed 
effects including treatment, time, interaction of time by treatment, and baseline SARS-CoV-2 
RNA level. Further specification of the MMRM model will be provided in the SAP. 
LSmeans (and 80% CIs and p-values) will be summarized.
A Bayesian Emax model will then be fitted to the Day 5 LSmeans and SEs from the MMRM 
analysis. Non-informative prior distributions for the placebo (E0), the difference in response 
(difTarget) between the highest dose (600 mg q12h) and placebo, and the residual standard 
deviation (sigma).
The fitted curve will be graphically displayed with 80% credible bands. The posterior 
medians and 80% credible intervals (10th and 90th percentiles of the relevant posterior 
distribution) will be reported for each randomized dose (including placebo) and their 
differences relative to placebo. If the Bayesian Emax model cannot be fitted to the data, or 
the data do not support a dose-response, the model may be simplified, or the analysis may not 
be performed and the primary results for the study will be based on the MMRM results at 
Day 5. More details on how this will be assessed will be described in the SAP. No 
adjustments will be made for multiplicity in the MMRM model.
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9.3.2.3. Supplementary Analyses
The MMRM analysis and Bayesian Emax dose-response model described in Section 9.3.2.2
will be repeated using the FAS instead of MFAS and use the E2 estimand strategy.
9.3.3. Secondary Endpoint(s)/Estimand(s) Analysis
Details on the definitions and analyses of secondary endpoints will be described in the SAP. 
Secondary endpoints include:
!
Change from baseline in SARS-CoV-2 RNA level on Days 3, 10 and 14.
!
Incidence of TEAEs.
!
Incidence of SAEs and AEs leading to discontinuations.
!
Incidence of clinically significant abnormal laboratory values, vital signs, and ECGs.
No formal statistical analysis will be conducted on any of the safety data listed above.
9.3.4. Tertiary/Exploratory Endpoint(s) Analysis
Exploratory endpoints may not be reported in the CSR and may be reported separately.
Details on the definitions and analyses of the exploratory endpoints, if reported in the CSR,
will be described in the SAP or equivalent analysis plan.
9.3.5. Other Safety Analyses
All safety analyses will be performed on the Safety Analysis Set.
9.3.5.1. Electrocardiogram Analyses
Changes from baseline for the ECG parameters HR, QTcF, PR interval, and QRS complex
will be summarized by treatment and time. The frequency of uncorrected QT values above 
500 ms will be tabulated.
The number (%) of participants with maximum post-dose QTcF values and maximum 
increases from baseline in the following categories will be tabulated by treatment: 
Safety QTcF Assessment
Degree of Prolongation
Mild (ms)
Moderate (ms)
Severe (ms)
Abs value
>450-480
>480-500
>500
Increase from baseline
30-60
>60
9.3.6. Other Analyses 
Pharmacogenomic or biomarker data from Retained Research Samples may be collected 
during or after the trial and retained for future analyses; the results of such analyses are not 
planned to be included in the CSR.
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9.4. Interim Analyses
A planned formal interim analysis for virological response and safety may be performed to 
assess SARS-CoV-2 RNA level after approximately 50% or more participants, ie, at least 
114 participants with baseline SARS-CoV-2 RNA level ≥4 log10 copies/mL, complete their 
study participation (including viral load assessment) through Day 5. The timing of the 
interim analysis is contingent on the recruitment rate.
Additional interim analysis may be performed for internal business decision-making or 
regulatory requests. Before any interim analyses are conducted, the final number and timings 
of interims, the details of the objectives, decision criteria, information dissemination plan, 
and method for maintaining the study blind as per Pfizer’s SOPs will be documented and 
approved in an IRC charter and interim analysis plan. The study team will remain blinded to 
all interim results.
Participants may be discontinued from the study intervention/study as a result of the interim 
analysis, as described in Section 7.
9.5. Sample Size Determination
A sufficient number of participants will be screened to achieve a total of approximately 228 
participants, with participants randomly assigned to PF-07817883 100, 300, or 600 mg q12h
and placebo in approximately a 1:1:2:2 ratio. Assuming 20% of participants will discontinue 
study drug treatment or have a baseline SARS-CoV-2 RNA level <4 log10 copies/mL,
approximately 180 participants (60 in each of PF-07817883 600 mg q12h and placebo, and 
30 in each of PF-07817883 100 mg q12h and 300 mg q12h) with baseline SARS-CoV-2 
RNA level ≥4 log10 copies/mL are expected to complete Day 5 of the study. Additional
participants may be randomized to ensure 180 participants with baseline SARS-CoV-2 RNA 
level ≥4 log10 copies/mL who complete study drug treatment.
The sample size is based on the primary efficacy endpoint, change from baseline in SARS-
CoV-2 RNA level at Day 5. 
 
!
;15
!
.15
Based on the above, 180 participants with baseline SARS-CoV-2 RNA level ≥4 log10
copies/mL who complete study drug treatment and 228 enrolled participants, in a 1:1:2:2 
randomization ratio, gives acceptable operating characteristics for the study.
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CCI
CCI
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9.6. Analysis of Pharmacokinetic Endpoints
The PK Concentration Population is defined as all enrolled participants who received at least 
1 dose of PF-07817883 and in whom at least 1 concentration value is reported. PK 
concentrations will be summarized and presented with descriptive statistics. A population PK 
modeling may be performed with the concentration data from this study alone or combined 
with data from other studies. In addition, a relationship between exposures and 
efficacy/safety endpoints may be evaluated using population PK/PD approach. Any 
population analyses conducted will not be part of the CSR and may be reported separately.
9.6.1. Early PK/PD Unblinding Plan
If needed, a PK/PD unblinding plan will be in place prior to the start of the PK/PD 
unblinding in accordance with applicable Pfizer SOPs for releasing randomization codes and 
breaking the study blind.
Under this plan, a group of statisticians, data programmer, PK/PD data provider, PK/PD 
analyst and PK/PD support would be unblinded in order to initiate the building of statistical 
models of the PK, dose/response as well as exposure/response analysis models and conduct 
associated simulations. The aim of this work would be to facilitate a fuller interpretation of 
the study upon completion (at appropriate interim milestone). This group will not serve on 
the study team during the period of early unblinding. The unblinding may occur at an 
appropriate time as defined in the data blinding plan to allow sufficient time for PK/PD 
analyses. PK/PD modeling and simulation may be used at or after the first planned interim 
analysis to inform dose selection for subsequent studies. If performed, these activities will 
only impact decisions at the program level and not impact the conduct of the ongoing study.
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10. SUPPORTING DOCUMENTATION AND OPERATIONAL CONSIDERATIONS
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations
10.1.1. Regulatory and Ethical Considerations
This study will be conducted in accordance with the protocol and with the following:
!
Consensus ethical principles derived from international guidelines, including the 
Declaration of Helsinki and CIOMS International Ethical Guidelines;
!
Applicable ICH GCP guidelines;
!
Applicable laws and regulations, including applicable privacy laws.
The protocol, protocol amendments, ICD, SRSD(s), and other relevant documents (eg, 
advertisements) must be reviewed and approved by the sponsor, submitted to an IRB/EC by 
the investigator, and reviewed and approved by the IRB/EC before the study is initiated.
Any amendments to the protocol will require IRB/EC approval before implementation of 
changes made to the study design, except for changes necessary to eliminate an immediate 
hazard to study participants.
Protocols and any substantial amendments to the protocol will require health authority 
approval prior to initiation except for changes necessary to eliminate an immediate hazard to 
study participants.
The investigator will be responsible for the following:
!
Providing written summaries of the status of the study to the IRB/EC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/EC;
!
Notifying the IRB/EC of SAEs or other significant safety findings as required by 
IRB/EC procedures;
!
Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 CFR, ICH GCP guidelines, the IRB/EC, European regulation 
536/2014 for clinical studies, European Medical Device Regulation 2017/745 for 
clinical device research, and all other applicable local regulations.
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the Protocol or ICH GCP
In the event of any prohibition or restriction imposed (ie, clinical hold) by an applicable 
regulatory authority in any area of the world, or if the investigator is aware of any new 
information that might influence the evaluation of the benefits and risks of the study 
intervention, Pfizer should be informed immediately. 
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In addition, the investigator will inform Pfizer immediately of any urgent safety measures 
taken by the investigator to protect the study participants against any immediate hazard, and 
of any serious breaches of this protocol or of the ICH GCP guidelines that the investigator 
becomes aware of.
10.1.2. Financial Disclosure
Investigators and sub-investigators will provide the sponsor with sufficient, accurate 
financial information as requested to allow the sponsor to submit complete and accurate 
financial certification or disclosure statements to the appropriate regulatory authorities.
Investigators are responsible for providing information on financial interests during the 
course of the study and for 1 year after completion of the study.
10.1.3. Informed Consent Process
The investigator or the investigator’s representative will explain the nature of the study, 
including the risks and benefits, to the participant or their legally authorized representative 
and answer all questions regarding the study. The participant or their legally authorized 
representative should be given sufficient time and opportunity to ask questions and to decide 
whether or not to participate in the trial.
Participants must be informed that their participation is voluntary. Participants or their legally 
authorized representative (if allowed by local regulations) will be required to sign a statement 
of informed consent that meets the requirements of 21 CFR 50, local regulations, ICH 
guidelines, privacy and data protection requirements, where applicable, and the IRB/EC or 
study center.
The investigator must ensure that each participant or their legally authorized representative is 
fully informed about the nature and objectives of the study, the sharing of data related to the 
study, and possible risks associated with participation, including the risks associated with the 
processing of the participant’s personal data. 
The participant or their legally authorized representative must be informed that their personal 
study-related data will be used by the sponsor in accordance with local data protection law. 
The level of disclosure must also be explained to the participant or their legally authorized 
representative.
The participant or their legally authorized representative must be informed that their medical 
records may be examined by Clinical Quality Assurance auditors or other authorized 
personnel appointed by the sponsor, by appropriate IRB/EC members, and by inspectors 
from regulatory authorities.
The investigator further must ensure that each study participant or their legally authorized 
representative is fully informed about their right to access and correct their personal data and 
to withdraw consent for the processing of their personal data.
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The medical record must include a statement that written informed consent was obtained 
before the participant was enrolled in the study and the date on which the written consent was 
obtained. The authorized person obtaining the informed consent must also sign the ICD.
Participants or their legally authorized representative must be reconsented to the most current 
version of the IRB/EC-approved ICD(s) during their participation in the study as required per 
local regulations.
A copy of the ICD(s) must be provided to the participant or their legally authorized 
representative (if allowed by local regulations).
10.1.4. Data Protection
All parties will comply with all applicable laws, including laws regarding the implementation 
of organizational and technical measures to ensure protection of participant data.
Participants’ personal data will be stored at the study site in encrypted electronic and/or paper
form and will be password protected or secured in a locked room to ensure that only 
authorized study staff have access. The study site will implement appropriate technical and 
organizational measures to ensure that the personal data can be recovered in the event of 
disaster. In the event of a potential personal data breach, the study site will be responsible for 
determining whether a personal data breach has in fact occurred and, if so, providing breach 
notifications as required by law.
To protect the rights and freedoms of participants with regard to the processing of personal 
data, participants will be assigned a single, participant-specific numerical code. Any 
participant records or data sets that are transferred to the sponsor will contain the numerical 
code; participant names will not be transferred. All other identifiable data transferred to the 
sponsor will be identified by this single, participant-specific code. The study site will 
maintain a confidential list of participants who participated in the study, linking each 
participant’s numerical code to their actual identity and medical record ID. In case of data 
transfer, the sponsor will protect the confidentiality of participants’ personal data consistent 
with the clinical study agreement and applicable privacy laws.
Information technology systems used to collect, process, and store study-related data are 
secured by technical and organizational security measures designed to protect such data 
against accidental or unlawful loss, alteration, or unauthorized disclosure or access.
The sponsor maintains SOPs on how to respond in the event of unauthorized access, use, or 
disclosure of sponsor information or systems.
10.1.5. Committees Structure
10.1.5.1. Data Monitoring Committee 
This study will use an IRC. The IRC is independent of the study team and includes only 
internal members. The IRC charter describes the role of the IRC in more detail.
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The IRC will be responsible for ongoing monitoring of the safety of participants in the study 
according to the charter. The recommendations made by the IRC will be forwarded to the 
appropriate authorized Pfizer personnel for review and final decision. Pfizer will 
communicate such decisions, which may include summaries of aggregate analyses of safety 
data, to regulatory authorities and investigators, as appropriate.
10.1.6. Dissemination of Clinical Study Data
Pfizer fulfills its commitment to publicly disclose clinical study results through posting the 
results of studies on www.clinicaltrials.gov (ClinicalTrials.gov), the EudraCT/CTIS, and/or 
www.pfizer.com, and other public registries and websites in accordance with applicable local 
laws/regulations. In addition, Pfizer reports study results outside of the requirements of local 
laws/regulations pursuant to its SOPs.
In all cases, study results are reported by Pfizer in an objective, accurate, balanced, and 
complete manner and are reported regardless of the outcome of the study or the country in 
which the study was conducted.
www.clinicaltrials.gov
Pfizer posts clinical trial results on www.clinicaltrials.gov for Pfizer-sponsored interventional 
studies (conducted in patients) that evaluate the safety and/or efficacy of a product, 
regardless of the geographical location in which the study is conducted. These results are 
submitted for posting in accordance with the format and timelines set forth by US law.
EudraCT/CTIS
Pfizer posts clinical trial results on EudraCT/CTIS for Pfizer-sponsored interventional studies 
in accordance with the format and timelines set forth by EU requirements.
www.pfizer.com
Pfizer posts CSR synopses and plain-language study results summaries on www.pfizer.com 
for Pfizer-sponsored interventional studies at the same time the corresponding study results 
are posted to www.clinicaltrials.gov. CSR synopses will have personally identifiable 
information anonymized.
Documents within marketing applications
Pfizer complies with applicable local laws/regulations to publish clinical documents included 
in marketing applications. Clinical documents include summary documents and CSRs 
including the protocol and protocol amendments, sample CRFs, and SAPs. Clinical 
documents will have personally identifiable information anonymized.
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Data sharing
Pfizer provides researchers secure access to participant-level data or full CSRs for the 
purposes of “bona-fide scientific research” that contributes to the scientific understanding of 
the disease, target, or compound class. Pfizer will make data from these trials available 
18 months after study completion. Participant-level data will be anonymized in accordance 
with applicable privacy laws and regulations. CSRs will have personally identifiable 
information anonymized.
Data requests are considered from qualified researchers with the appropriate competencies to 
perform the proposed analyses. Research teams must include a biostatistician. Data will not 
be provided to applicants with significant conflicts of interest, including individuals 
requesting access for commercial/competitive or legal purposes.
10.1.7. Data Quality Assurance
All participant data relating to the study will be recorded on printed or electronic CRF unless 
transmitted to the sponsor or designee electronically (eg, laboratory data). The investigator is 
responsible for verifying that data entries are accurate and correct by physically or 
electronically signing the CRF.
Guidance on completion of CRFs will be provided in the CRF Completion Requirements 
document.
The investigator must ensure that the CRFs are securely stored at the study site in encrypted 
electronic form and are password protected to prevent access by unauthorized third parties.
QTLs are predefined parameters that are monitored during the study. Important deviations 
from the QTLs and any remedial actions taken will be summarized in the CSR.
The investigator must permit study-related monitoring, audits, IRB/EC review, and 
regulatory agency inspections and provide direct access to source records and documents.
This verification may also occur after study completion. It is important that the 
investigator(s) and their relevant personnel are available during the monitoring visits and 
possible audits or inspections and that sufficient time is devoted to the process.
Monitoring details describing strategy, including definition of study-critical data items and 
processes (eg, risk-based initiatives in operations and quality such as risk management and 
mitigation strategies and analytical risk-based monitoring), methods, responsibilities, and 
requirements, including handling of noncompliance issues and monitoring techniques 
(central, virtual, or on-site monitoring), are provided in the data management plan and 
monitoring plan maintained and utilized by the sponsor or designee.
The sponsor or designee is responsible for the data management of this study, including 
quality checking of the data.
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Records and documents, including signed ICDs, pertaining to the conduct of this study must 
be retained by the investigator for 15 years after study completion unless local regulations or 
institutional policies require a longer retention period. No records may be destroyed during 
the retention period without the written approval of the sponsor. No records may be 
transferred to another location or party without written notification to the sponsor. The 
investigator must ensure that the records continue to be stored securely for as long as they are 
maintained.
When participant data are to be deleted, the investigator will ensure that all copies of such 
data are promptly and irrevocably deleted from all systems.
The investigator(s) will notify the sponsor or its agents immediately of any regulatory 
inspection notification in relation to the study. Furthermore, the investigator will cooperate 
with the sponsor or its agents to prepare the investigator site for the inspection and will allow 
the sponsor or its agent, whenever feasible, to be present during the inspection. The 
investigator site and investigator will promptly resolve any discrepancies that are identified 
between the study data and the participant’s medical records. The investigator will promptly 
provide copies of the inspection findings to the sponsor or its agent. Before response 
submission to the regulatory authorities, the investigator will provide the sponsor or its 
agents with an opportunity to review and comment on responses to any such findings.
10.1.8. Source Documents
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected. Source documents are filed at the investigator site.
Data reported on the CRF or entered in the eCRF that are from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
investigator may need to request previous medical records or transfer records, depending on 
the study. Also, current medical records must be available.
Definition of what constitutes a source document and its origin can be found in the Source 
Document Locator, which is maintained by the sponsor.
Description of the use of the computerized system is documented in the data management 
plan, which is maintained by the sponsor.
The investigator must maintain accurate documentation (source record) that supports the 
information entered in the CRF.
The sponsor or designee will perform monitoring to confirm that data entered into the CRF 
by authorized site personnel are accurate, complete, and verifiable from source documents; 
that the safety and rights of participants are being protected; and that the study is being 
conducted in accordance with the currently approved protocol and any other study 
agreements, ICH GCP guidelines, and all applicable regulatory requirements.
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10.1.9. Study and Site Start and Closure
The study start date is the date of the first participant’s first visit.
The sponsor designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of the sponsor, including (but not limited to) 
regulatory authority decision, change in opinion of the IRB/EC, or change in benefit-risk 
assessment. Study sites will be closed upon study completion. A study site is considered 
closed when all required documents and study supplies have been collected and a study-site 
closure visit has been performed.
The investigator may initiate study-site closure at any time upon notification to the sponsor 
or designee/CRO if requested to do so by the responsible IRB/EC or if such termination is 
required to protect the health of study participants.
Reasons for the early closure of a study site by the sponsor may include but are not limited 
to:
!
Failure of the investigator to comply with the protocol, the requirements of the 
IRB/EC or local health authorities, the sponsor’s procedures, or the ICH GCP 
guidelines;
!
Inadequate recruitment of participants by the investigator;
!
Discontinuation of further study intervention development.
If the study is prematurely terminated or suspended, the sponsor shall promptly inform the 
investigators, the ECs/IRBs, the regulatory authorities, and any CRO(s) used in the study of 
the reason for termination or suspension, as specified by the applicable regulatory 
requirements. The investigator shall promptly inform the participant and should assure 
appropriate participant therapy and/or follow-up.
Study termination is also provided for in the clinical study agreement. If there is any conflict 
between the contract and this protocol, the contract will control as to termination rights.
10.1.10. Publication Policy
For multicenter trials, the primary publication will be a joint publication developed by the 
investigator and Pfizer reporting the primary endpoint(s) of the study covering all study sites. 
The investigator agrees to refer to the primary publication in any subsequent publications. 
Pfizer will not provide any financial compensation for the investigator’s participation in the 
preparation of the primary congress abstract, poster, presentation, or primary manuscript for 
the study.
Investigators are free to publish individual center results that they deem to be clinically 
meaningful after publication of the overall results of the study or 12 months after primary 
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completion date or study completion at all sites, whichever occurs first, subject to the other 
requirements described in this section.
The investigator will provide Pfizer an opportunity to review any proposed publication or 
any other type of disclosure of the study results (collectively, “publication”) before it is 
submitted or otherwise disclosed and will submit all publications to Pfizer 30 days before 
submission. If any patent action is required to protect intellectual property rights, the 
investigator agrees to delay the disclosure for a period not to exceed an additional 60 days 
upon request from Pfizer. This allows Pfizer to protect proprietary information and to provide 
comments, and the investigator will, on request, remove any previously undisclosed 
confidential information before disclosure, except for any study-intervention or Pfizer-related 
information necessary for the appropriate scientific presentation or understanding of the 
study results. For joint publications, should there be disagreement regarding interpretation 
and/or presentation of specific analysis results, resolution of, and responsibility for, such 
disagreements will be the collective responsibility of all authors of the publication.
For all publications relating to the study, the investigator and Pfizer will comply with 
recognized ethical standards concerning publications and authorship, including those 
established by the International Committee of Medical Journal Editors. The investigator will 
disclose any relationship with Pfizer and any relevant potential conflicts of interest, including 
any financial or personal relationship with Pfizer, in any publications. All authors will have 
access to the relevant statistical tables, figures, and reports (in their original format) required 
to develop the publication.
10.1.11. Sponsor’s Medically Qualified Individual 
The contact information for the sponsor’s MQI for the study is documented in the study 
contact list located in the supporting study documentation/study portal or other electronic 
system.
To facilitate access to their investigator and the sponsor’s MQI for study-related medical 
questions or problems from non-study healthcare professionals, participants are provided 
with an ECC at the time of informed consent. The ECC contains, at a minimum, (a) protocol 
and study intervention identifiers, (b) participant’s study identification number, (c) site 
emergency phone number active 24 hours/day, 7 days per week, and (d) Pfizer Call Center 
number.
The ECC is intended to augment, not replace, the established communication pathways 
between the participant and their investigator and site staff, and between the investigator and 
sponsor study team. The ECC is only to be used by healthcare professionals not involved in 
the research study, as a means of reaching the investigator or site staff related to the care of a 
participant. The Pfizer Call Center number is to be used when the investigator and site staff 
are unavailable. The Pfizer Call Center number is not for use by the participant directly; if a 
participant calls that number directly, they will be directed back to the investigator site.
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10.2. Appendix 2: Clinical Laboratory Tests
The following safety laboratory tests will be performed at times defined in the SoA section of 
this protocol. Additional laboratory results may be reported on these samples as a result of 
the method of analysis or the type of analyzer used by the clinical laboratory, or as derived 
from calculated values. These additional tests would not require additional collection of 
blood. Unscheduled clinical laboratory measurements may be obtained at any time during the 
study to assess any perceived safety issues.
Table 4.
Protocol Required Safety Laboratory Assessments
Hematology
Chemistry
Urinalysis
Othera
Additional Tests 
(Needed for Suspected
Hy’s Law or DIKI)
Hemoglobin
Hematocrit
RBC count
Platelet count
WBC count
Total neutrophils 
(Abs)
Eosinophils (Abs)
Monocytes (Abs)
Basophils (Abs)
Lymphocytes 
(Abs)
BUN or Urea 
Creatinineb
Cystatin C
eGFR 
(combined 
Scr+Scys)
Glucose
Calcium
Sodium
Potassium
Chloride
Total CO2 
(bicarbonate)
AST, ALT
Total bilirubin
Alkaline 
phosphatase
Albumin
Total protein
Local dipstick:
pH
Glucose (qual)
Protein (qual)
Blood (qual)
Ketones
Nitrites
Leukocyte 
esterase
Laboratory:
Albumin (urine)
Creatinine 
(urine)
Urine albumin to 
creatinine ratio 
(UACR)
Microscopy and 
culturec
Ferritin
D-dimer
hs-CRP
Procalcitonin
LDH
CK
Haptoglobin
SARS-CoV-2 
serology (IgM, IgG)d
At screening:
FSHe
Pregnancy test 
(βhCG)f
Hy’s Law
AST, ALT 
Total bilirubin
Albumin 
Alkaline phosphatase 
Direct bilirubin
Indirect bilirubin
Creatine kinase
GGT
PT/INR
Total bile acids
Acetaminophen drug 
and/or protein adduct 
levels
DIKI
Cystatin C
eGFR
Albumin (urine)
Creatinine (urine)
Urine albumin to 
creatinine ratio (UACR)
a. For Day 10 sample, only SARS-CoV-2 serology is evaluated.
b. eGFR will be calculated using the method developed by the CKD-EPI using serum creatinine.12
c. Only if UTI is suspected and urine dipstick is positive for nitrites or leukocyte esterase or both.
d. SARS-CoV-2 serology is evaluated with only Day 1 and Day 10 samples.
e. FSH testing is performed locally for confirmation of postmenopausal status only.
f. Local urine testing will be standard for the protocol unless serum testing is required by local regulation or 
IRB/EC. Serum or urine β-hCG for female participants of childbearing potential.
The investigator must review the laboratory report, document this review, and record any 
clinically relevant changes occurring during the study in the AE section of the CRF.
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10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting
10.3.1. Definition of AE
AE Definition
!
An AE is any untoward medical occurrence in a patient or clinical study 
participant, temporally associated with the use of study intervention, whether or not 
considered related to the study intervention.
!
Note: An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease (new or exacerbated) 
temporally associated with the use of study intervention.
Events Meeting the AE Definition
!
Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) 
or other safety assessments (eg, ECG, radiological scans, vital sign measurements), 
including those that worsen from baseline, considered clinically significant in the 
medical and scientific judgment of the investigator. Any abnormal laboratory test 
results that meet any of the conditions below must be recorded as an AE:
!
Is associated with accompanying symptoms.
!
Requires additional diagnostic testing or medical/surgical intervention.
!
Leads to a change in study dosing (outside of any protocol-specified dose 
adjustments) or discontinuation from the study, significant additional 
concomitant drug treatment, or other therapy.
!
Exacerbation of a chronic or intermittent preexisting condition, including an 
increase in either frequency and/or intensity of the condition.
!
New condition detected or diagnosed after study intervention administration, even 
though it may have been present before the start of the study.
!
Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction.
!
Signs, symptoms, or the clinical sequelae of a suspected overdose of either study 
intervention or a concomitant medication. Overdose per se will not be reported as 
an AE or SAE unless it is an intentional overdose taken with possible 
suicidal/self-harming intent. Such overdoses should be reported regardless of 
sequelae.
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Events NOT Meeting the AE Definition
!
Any clinically significant abnormal laboratory findings or other abnormal safety 
assessments that are associated with the underlying disease, unless judged by the 
investigator to be more severe than expected for the participant’s condition.
!
The disease/disorder being studied or expected progression, signs, or symptoms of 
the disease/disorder being studied, unless more severe than expected for the 
participant’s condition.
!
Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that 
leads to the procedure is the AE.
!
Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital).
!
Anticipated day-to-day fluctuations of preexisting disease(s) or condition(s) present 
or detected at the start of the study that do not worsen.
10.3.2. Definition of an SAE
An SAE is defined as any untoward medical occurrence that, at any dose, meets one 
or more of the criteria listed below:
a. Results in death
b. Is life-threatening
The term “life-threatening” in the definition of “serious” refers to an event in which the 
participant 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.
c.
Requires inpatient hospitalization or prolongation of existing hospitalization
In general, hospitalization signifies that the participant has been admitted (usually 
involving at least an overnight stay) at the hospital or emergency ward for observation 
and/or treatment that would not have been appropriate in the physician’s office or 
outpatient setting. Complications that occur during hospitalization are AEs. If a 
complication prolongs hospitalization or fulfills any other serious criteria, the event is 
serious. When in doubt as to whether “hospitalization” occurred or was necessary, the 
AE should be considered serious.
Hospitalization for elective treatment of a preexisting condition that did not worsen 
from baseline is not considered an AE.
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d. Results in persistent or significant disability/incapacity
!
The term disability means a substantial disruption of a person’s ability to conduct 
normal life functions.
!
This definition is not intended to include experiences of relatively minor medical 
significance, such as uncomplicated headache, nausea, vomiting, diarrhea, 
influenza, and accidental trauma (eg, sprained ankle), that may interfere with or 
prevent everyday life functions but do not constitute a substantial disruption.
e.
Is a congenital anomaly/birth defect
f.
Is a suspected transmission via a Pfizer product of an infectious agent, pathogenic 
or nonpathogenic
The event may be suspected from clinical symptoms or laboratory findings indicating 
an infection in a participant exposed to a Pfizer product. The terms “suspected 
transmission” and “transmission” are considered synonymous. These cases are 
considered unexpected and handled as serious expedited cases by pharmacovigilance 
personnel. Such cases are also considered for reporting as product defects, if 
appropriate.
g. Other situations:
!
Medical or scientific judgment should be exercised by the investigator in deciding 
whether SAE reporting is appropriate in other situations, such as significant
medical events that may jeopardize the participant or may require medical or 
surgical intervention to prevent one of the other outcomes listed in the above 
definition. These events should usually be considered serious.
!
Examples of such events include invasive or malignant cancers, intensive treatment 
in an emergency room or at home for allergic bronchospasm, blood dyscrasias or
convulsions that do not result in hospitalization, or development of drug 
dependency or drug abuse.
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10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During the Active 
Collection Period 
AE and SAE Recording/Reporting
The table below summarizes the requirements for recording AEs on the CRF and for 
reporting SAEs on the CT SAE Report Form to Pfizer Safety throughout the active 
collection period. These requirements are delineated for 3 types of events: (1) SAEs; (2) 
nonserious AEs; and (3) exposure to the study intervention under study during pregnancy 
or breastfeeding, and occupational exposure. 
It should be noted that the CT SAE Report Form for reporting of SAE information is not 
the same as the AE page of the CRF. When the same data are collected, the forms must be 
completed in a consistent manner. AEs should be recorded using concise medical 
terminology and the same AE term should be used on both the CRF and the CT SAE 
Report Form for reporting of SAE information.
Safety Event
Recorded on the CRF
Reported on the CT SAE 
Report Form to Pfizer 
Safety Within 24 Hours of 
Awareness
SAE
All
All
Nonserious AE
All
None
Exposure to the study 
intervention under study 
during pregnancy or 
breastfeeding 
All AEs or SAEs associated 
with EDP or EDB
Note: Instances of EDP or 
EDB not associated with an 
AE or SAE are not captured 
in the CRF
All instances of EDP are 
reported (whether or not 
there is an associated 
SAE)*
All instances of EDB are 
reported (whether or not 
there is an associated 
SAE)**
Environmental or 
occupational exposure to 
the product under study to 
a nonparticipant (not 
involving EDP or EDB)
None. Exposure to a study 
nonparticipant is not 
collected on the CRF
The exposure (whether or 
not there is an associated 
AE or SAE) must be 
reported***
*
EDP (with or without an associated AE or SAE): any pregnancy information is reported to Pfizer 
Safety using the CT SAE Report Form and EDP Supplemental Form; if the EDP is associated with an 
SAE, then the SAE is reported to Pfizer Safety using the CT SAE Report Form. 
** EDB is reported to Pfizer Safety using the CT SAE Report Form, which would also include details
of any SAE that might be associated with the EDB. 
*** Environmental or occupational exposure: AEs or SAEs associated with occupational exposure 
are reported to Pfizer Safety using the CT SAE Report Form. 
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!
When an AE or SAE occurs, it is the responsibility of the investigator to review all 
documentation (eg, hospital progress notes, laboratory reports, and diagnostic 
reports) related to the event.
!
The investigator will then record all relevant AE or SAE information in the CRF.
!
It is not acceptable for the investigator to send photocopies of the participant’s 
medical records to Pfizer Safety in lieu of completion of the CT SAE Report 
Form/AE or SAE CRF page.
!
There may be instances when copies of medical records for certain cases are 
requested by Pfizer Safety. In this case, all participant identifiers, with the 
exception of the participant number, will be redacted on the copies of the medical 
records before submission to Pfizer Safety.
!
The investigator will attempt to establish a diagnosis of the event based on signs, 
symptoms, and/or other clinical information. Whenever possible, the diagnosis (not 
the individual signs/symptoms) will be documented as the AE or SAE.
Assessment of Intensity
The investigator will make an assessment of intensity for each AE and SAE reported 
during the study and assign it to 1 of the following categories, which are based on the 
DAIDS Table for Grading the Severity of Adult and Pediatric Adverse Events14, version 
2.1 (July 2017):
GRADE
Clinical Description of Severity
1
MILD adverse event
2
MODERATE adverse event
3
SEVERE adverse event
4
POTENTIALLY LIFE-THREATENING event 
5
DEATH RELATED TO adverse event
An event is defined as “serious” when it meets at least 1 of the predefined outcomes as 
described in the definition of an SAE, NOT when it is rated as severe.
Assessment of Causality
!
The investigator is obligated to assess the relationship between study intervention 
and each occurrence of each AE or SAE. The investigator will use clinical 
judgment to determine the relationship.
!
A “reasonable possibility” of a relationship conveys that there are facts, evidence, 
and/or arguments to suggest a causal relationship, rather than a relationship cannot 
be ruled out.
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!
Alternative causes, such as underlying disease(s), concomitant therapy, and other 
risk factors, as well as the temporal relationship of the event to study intervention 
administration, will be considered and investigated.
!
The investigator will also consult the IB and/or product information, for marketed 
products, in their assessment.
!
For each AE or SAE, the investigator must document in the medical notes that they 
have reviewed the AE or SAE and have provided an assessment of causality.
!
There may be situations in which an SAE has occurred and the investigator has 
minimal information to include in the initial report to the sponsor. However, it is 
very important that the investigator always make an assessment of causality 
for every event before the initial transmission of the SAE data to the sponsor.
!
The investigator may change their opinion of causality in light of follow-up 
information and send an SAE follow-up report with the updated causality 
assessment.
!
The causality assessment is one of the criteria used when determining regulatory 
reporting requirements.
!
If the investigator does not know whether or not the study intervention caused the 
event, then the event will be handled as “related to study intervention” for reporting 
purposes, as defined by the sponsor. In addition, if the investigator determines that 
an SAE is associated with study procedures, the investigator must record this 
causal relationship in the source documents and CRF, and report such an 
assessment in the dedicated section of the CT SAE Report Form and in accordance 
with the SAE reporting requirements.
Follow-Up of AEs and SAEs
!
The investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations, as medically indicated or as requested by the 
sponsor, to elucidate the nature and/or causality of the AE or SAE as fully as 
possible. This may include additional laboratory tests or investigations, 
histopathological examinations, or consultation with other healthcare providers.
!
If a participant dies during participation in the study or during a recognized 
follow-up period, the investigator will provide Pfizer Safety with a copy of any 
postmortem findings, including histopathology. 
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!
New or updated information will be recorded in the originally submitted 
documents.
!
The investigator will submit any updated SAE data to the sponsor within 24 hours 
of receipt of the information.
10.3.4. Reporting of SAEs
SAE Reporting to Pfizer Safety via an Electronic Data Collection Toll DCT
!
The primary mechanism for reporting an SAE to Pfizer Safety will be the 
electronic DCT.
!
If the electronic system is unavailable, then the site will use the paper SAE DCT
(see next section) to report the event within 24 hours.
!
The site will enter the SAE data into the electronic DCT (eg, eSAE or PSSA) or 
paper form (as applicable) as soon as the data become available.
!
After the study is completed at a given site, the electronic DCT will be taken 
off-line to prevent the entry of new data or changes to existing data.
!
If a site receives a report of a new SAE from a study participant or receives updated 
data on a previously reported SAE after the electronic DCT has been taken off-line, 
then the site can report this information on a paper SAE form (see next section) or 
to Pfizer Safety by telephone.
SAE Reporting to Pfizer Safety via the CT SAE Report Form
!
Facsimile transmission of the CT SAE Report Form is the preferred method to 
transmit this information to Pfizer Safety.
!
In circumstances when the facsimile is not working, an alternative method should 
be used, eg, secured (Transport Layer Security) or password-protected email. If 
none of these methods can be used, notification by telephone is acceptable with a 
copy of the CT SAE Report Form sent by overnight mail or courier service.
!
Initial notification via telephone does not replace the need for the investigator to 
complete and sign the CT SAE Report Form pages within the designated reporting 
time frames.
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10.4. Appendix 4: Contraceptive and Barrier Guidance
10.4.1. Male Participant Reproductive Inclusion Criteria
Male participants are eligible to participate if they agree to the following requirements during 
the intervention period and for at least 28 days after the last dose of study intervention, which 
corresponds to the time needed to eliminate reproductive safety risk of the study 
intervention(s):
!
Refrain from donating sperm.
PLUS either:
!
Be abstinent from heterosexual intercourse as their preferred and usual lifestyle 
(abstinent on a long-term and persistent basis) and agree to remain abstinent.
OR
!
Must agree to use contraception/barrier as detailed below:
!
Agree to use a male condom, and should also be advised of the benefit for a 
female partner to use a highly effective method of contraception as a condom may 
break or leak when having sexual intercourse with a WOCBP who is not currently 
pregnant.
!
In addition to male condom use, a highly effective method of contraception may be 
considered in WOCBP partners of male participants (refer to the list of highly 
effective methods below in Section 10.4.4).
10.4.2. Female Participant Reproductive Inclusion Criteria
The criteria below are part of Inclusion Criterion 1 (Age and Sex; Section 5.1) and specify 
the reproductive requirements for including female participants. Refer to Section 10.4.4 for a 
complete list of contraceptive methods permitted in the study. 
A female participant is eligible to participate if she (a) is not pregnant or breastfeeding; and 
(b) at least 1 of the following conditions applies:
!
Is not a WOCBP (see definition in Section 10.4.3).
OR
!
Is a WOCBP who agrees to use a highly effective contraceptive method (failure rate 
of <1% per year) with low user dependency during the intervention period and for at 
least 28 days after the last dose of study intervention, which corresponds to the time 
needed to eliminate any reproductive safety risk of the study intervention(s). The 
investigator should evaluate the effectiveness of the contraceptive method in 
relationship to the first dose of study intervention.
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OR
!
Is a WOCBP and agrees to use a highly effective (failure rate of <1% per year) user-
dependent method of contraception during the intervention period and for at least 28
days after the last dose of study intervention, which corresponds to the time needed to 
eliminate any reproductive safety risk of the study intervention(s). In addition to her 
use of the highly effective method above, she agrees to concurrently use an effective 
barrier method. The investigator should evaluate the effectiveness of the 
contraceptive method in relationship to the first dose of study intervention.
The investigator is responsible for reviewing the woman’s medical history, menstrual history,
and recent sexual activity in order to decrease the risk of enrolling a woman with an early, 
undetected pregnancy. 
10.4.3. Woman of Childbearing Potential
A woman is considered fertile following menarche and until becoming postmenopausal 
unless permanently sterile (see below).
If fertility is unclear (eg, amenorrhea in adolescents or athletes) and a menstrual cycle cannot 
be confirmed before the first dose of study intervention, additional evaluation should be 
considered.
Women in the following categories are not considered WOCBP:
1. Premenopausal female with 1 of the following:
!
Documented hysterectomy;
!
Documented bilateral salpingectomy;
!
Documented bilateral oophorectomy.
For individuals with permanent infertility due to a medical cause other than the above (eg, 
mullerian agenesis, androgen insensitivity), investigator discretion should be applied to 
determining study entry.
Note: Documentation for any of the above categories can come from the site personnel’s 
review of the participant’s medical records, medical examination, or medical history 
interview. The method of documentation should be recorded in the participant’s medical 
record for the study.
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2. Postmenopausal female:
!
A postmenopausal state is defined as no menses for 12 months without an alternative 
medical cause. In addition:
!
A high FSH level in the postmenopausal range must be used to confirm a 
postmenopausal state in women under 60 years of age and not using hormonal 
contraception or HRT. 
!
A female on HRT and whose menopausal status is in doubt will be required to use 
one of the highly effective nonestrogen hormonal contraception methods if she
wishes to continue her HRT during the study. Otherwise, she must discontinue 
HRT to allow confirmation of postmenopausal status before study enrollment.
10.4.4. Contraception Methods
Contraceptive use by men or women should be consistent with local availability/regulations 
regarding the use of contraceptive methods for those participating in clinical trials.
The following contraceptive methods are appropriate for this study:
Highly Effective Methods That Have Low User Dependency 
1. Implantable progestogen-only hormone contraception associated with inhibition of 
ovulation.
2. Intrauterine device.
3. Intrauterine hormone-releasing system.
4. Bilateral tubal occlusion.
5. Vasectomized partner.
!
Vasectomized partner is a highly effective contraceptive method provided that the 
partner is the sole sexual partner of the WOCBP and the absence of sperm has 
been confirmed. If not, an additional highly effective method of contraception 
should be used. The spermatogenesis cycle is approximately 90 days.
Highly Effective Methods That Are User Dependent 
6. Combined (estrogen- and progestogen-containing) hormonal contraception associated 
with inhibition of ovulation:
!
Oral + barrier*
!
Intravaginal + barrier*
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!
Transdermal + barrier*
7. Progestogen-only hormone contraception associated with inhibition of ovulation:
!
Oral + barrier*
!
Injectable + barrier*
8. Sexual Abstinence
Sexual abstinence is considered a highly effective method only if defined as 
refraining from heterosexual intercourse during the entire period of risk associated 
with the study intervention. The reliability of sexual abstinence needs to be evaluated 
in relation to the duration of the study and the preferred and usual lifestyle of the 
participant.
* Acceptable barrier methods to be used concomitantly with options 6 or 7 for the study 
include any of the following:
!
Male or female condom with or without spermicide;
!
Cervical cap, diaphragm, or sponge with spermicide;
!
A combination of male condom with either cervical cap, diaphragm, or sponge 
with spermicide (double-barrier methods).
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10.5. Appendix 5: Genetics
Use/Analysis of DNA
!
Genetic variation may impact a participant’s response to study intervention, 
susceptibility to, and severity and progression of disease. Therefore, where local 
regulations and IRBs/ECs allow, a blood sample will be collected for DNA analysis.
!
The scope of the genetic research may be narrow (eg, 1 or more candidate genes) or 
broad (eg, the entire genome), as appropriate to the scientific question under 
investigation.
!
The samples may be analyzed as part of a multi-study assessment of genetic factors 
involved in the response to study intervention or study interventions of this class to 
understand treatments for the disease(s) under study or the disease(s) themselves.
!
The results of genetic analyses may be reported in the CSR or in a separate study 
summary, or may be used for internal decision making without being included in a 
study report.
!
The sponsor will store the DNA samples in a secure storage space with adequate 
measures to protect confidentiality. 
!
The samples will be retained as indicated:
!
Retained samples will be stored indefinitely or for another period as per local 
requirements.
!
Participants may withdraw their consent for the storage and/or use of their Retained 
Research Samples at any time by making a request to the investigator; in this case, 
any remaining material will be destroyed. Data already generated from the samples 
will be retained to protect the integrity of existing analyses.
!
Samples for genetic research will be labeled with a code. The key between the code 
and the participant’s personally identifying information (eg, name, address) will be 
held securely at the study site. 
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10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments and 
Study Intervention Rechallenge Guidelines
Potential Cases of Drug-Induced Liver Injury
Humans exposed to a drug who show no sign of liver injury (as determined by elevations in 
transaminases) are termed “tolerators,” while those who show transient liver injury but adapt 
are termed “adaptors.” In some participants, transaminase elevations are a harbinger of a 
more serious potential outcome. These participants fail to adapt and therefore are 
“susceptible” to progressive and serious liver injury, commonly referred to as DILI. 
Participants who experience a transaminase elevation above 3 × ULN should be monitored 
more frequently to determine if they are “adaptors” or are “susceptible.”
In the majority of DILI cases, elevations in AST and/or ALT precede T bili elevations (>2 × 
ULN) by several days or weeks. The increase in T bili typically occurs while AST/ALT is/are 
still elevated above 3 × ULN (ie, AST/ALT and T bili values will be elevated within the same 
laboratory sample). In rare instances, by the time T bili elevations are detected, AST/ALT 
values might have decreased. This occurrence is still regarded as a potential DILI. Therefore, 
abnormal elevations in either AST OR ALT in addition to T bili that meet the criteria outlined 
below are considered potential DILI (assessed per Hy’s law criteria) cases and should always 
be considered important medical events, even before all other possible causes of liver injury 
have been excluded.
The threshold of laboratory abnormalities for a potential DILI case depends on the 
participant’s individual baseline values and underlying conditions. Participants who present 
with the following laboratory abnormalities should be evaluated further as potential DILI 
(Hy’s law) cases to definitively determine the etiology of the abnormal laboratory values:
!
Participants with AST/ALT and T bili baseline values within the normal range who 
subsequently present with AST OR ALT values ≥3 × ULN AND a T bili value 
≥2 × ULN with no evidence of hemolysis and an alkaline phosphatase value 
<2 × ULN or not available.
!
For participants with baseline AST OR ALT OR T bili values above the ULN, the 
following threshold values are used in the definition mentioned above, as needed, 
depending on which values are above the ULN at baseline:
!
Preexisting AST or ALT baseline values above the normal range: AST or ALT 
values ≥2 times the baseline values AND ≥3 × ULN; or ≥8 × ULN (whichever is 
smaller).
!
Preexisting values of T bili above the normal range: T bili level increased from 
baseline value by an amount of ≥1 × ULN or if the value reaches ≥3 × ULN 
(whichever is smaller).
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Rises in AST/ALT and T bili separated by more than a few weeks should be assessed 
individually based on clinical judgment; any case where uncertainty remains as to whether it 
represents a potential Hy’s law case should be reviewed with the sponsor. 
The participant should return to the investigator site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the abnormal results. This evaluation should 
include laboratory tests, detailed history, and physical assessment.
In addition to repeating measurements of AST and ALT and T bili for suspected Hy’s law
cases, additional laboratory tests should include albumin, CK, direct and indirect bilirubin, 
GGT, PT/INR, total bile acids, and alkaline phosphatase. Consideration should also be given 
to drawing a separate tube of clotted blood and an anticoagulated tube of blood for further 
testing, as needed, for further contemporaneous analyses at the time of the recognized initial 
abnormalities to determine etiology. A detailed history, including relevant information, such 
as review of ethanol, acetaminophen/paracetamol (either by itself or as a coformulated 
product in prescription or over-the-counter medications), recreational drug, or supplement 
(herbal) use and consumption, family history, sexual history, travel history, history of contact 
with a jaundiced person, surgery, blood transfusion, history of liver or allergic disease, and 
potential occupational exposure to chemicals, should be collected. Further testing for acute 
hepatitis A, B, C, D, and E infection, liver imaging (eg, biliary tract), and collection of serum 
samples for acetaminophen/paracetamol drug and/or protein adduct levels may be warranted. 
All cases demonstrated on repeat testing as meeting the laboratory criteria of AST/ALT and 
T bili elevation defined above should be considered potential DILI (Hy’s law) cases if no 
other reason for the LFT abnormalities has yet been found. Such potential DILI (Hy’s law) 
cases are to be reported as SAEs, irrespective of availability of all the results of the 
investigations performed to determine etiology of the LFT abnormalities.
A potential DILI (Hy’s law) case becomes a confirmed case only after all results of 
reasonable investigations have been received and have excluded an alternative etiology.
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10.7. Appendix 7: Kidney Safety Monitoring Guidelines
10.7.1. Laboratory Assessment of Change in Kidney Function and Detection of Kidney 
Injury
Standard kidney safety monitoring requires assessment of baseline and postbaseline serum 
creatinine (Scr measurement to eGFR [Scr-based eGFR] or [eCrCl]). Baseline and 
postbaseline Scys makes it feasible to distinguish AKI from other causes of Scr increase. If 
Scr increase is confirmed after baseline, then reflex measurement of Scys is indicated to 
estimate the combined Scr-Scys eGFR calculation (for adults only).
Regardless of whether kidney function monitoring tests are required as a routine safety 
monitoring procedure in the study, if the investigator or sponsor deems it necessary to further 
assess kidney safety and quantify kidney function, then these test results should be managed 
and followed per standard of care.
10.7.2. Age-Specific Kidney Function Calculation Recommendations
10.7.2.1. Adults (18 Years and Above)—2021 CKD-EPI Equations
2021 CKD-
EPI          
Scr Only
Scr
(mg/dL)
Scys
(mg/L)
Recommended eGFR Equation
Female
if ≤ 0.7
N/A
eGFR = 143 × (Scr/0.7)-0.241  ×  (0.9938)Age
Female
if > 0.7
N/A
eGFR = 143 × (Scr/0.7)-1.200  ×  (0.9938)Age
Male
if ≤ 0.9
N/A
eGFR = 142 × (Scr/0.9)-0.302  ×  (0.9938)Age
Male
if > 0.9
N/A
eGFR = 142 × (Scr/0.9)-1.200  ×  (0.9938)Age
2021 CKD-
EPI          
Scr-Scys 
Combined
Scr
(mg/dL)
Scys
(mg/L)
Recommended eGFR Equation
Female
if ≤ 0.7
if ≤ 0.8
eGFR = 130 × (Scr/0.7)-0.219  × (Scys/0.8)-0.323  × (0.9961)Age
Female
if ≤ 0.7
if > 0.8
eGFR = 130 × (Scr/0.7)-0.219  × (Scys/0.8)-0.778  × (0.9961)Age
Female
if > 0.7
if ≤ 0.8
eGFR = 130 × (Scr/0.7)-0.544  × (Scys/0.8)-0.323  × (0.9961)Age
Female
if > 0.7
if > 0.8
eGFR = 130 × (Scr/0.7)-0.544  × (Scys/0.8)-0.778  × (0.9961)Age
Male
if ≤ 0.9
if ≤ 0.8
eGFR = 135 × (Scr/0.9)-0.144  × (Scys/0.8)-0.323  × (0.9961)Age
Male
if ≤ 0.9
if > 0.8
eGFR = 135 × (Scr/0.9)-0.144  × (Scys/0.8)-0.778  × (0.9961)Age
Male
if > 0.9
if ≤ 0.8
eGFR = 135 × (Scr/0.9)-0.544  ×  (Scys/0.8)-0.323  × (0.9961)Age
Male
if > 0.9
if > 0.8
eGFR = 135 × (Scr/0.9)-0.544  ×  (Scys/0.8)-0.778  × (0.9961)Age
Inker LA et al. N Engl J Med. 2021;385:1737-49.16
10.7.3. Adverse Event Grading for Kidney Safety Laboratory Abnormalities
AE grading for decline in kidney function (ie, eGFR or eCrCl) will be according to KDIGO
criteria. 
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10.8. Appendix 8: ECG Findings of Potential Clinical Concern
ECG Findings That May Qualify as AEs
!
Marked sinus bradycardia (rate <40 bpm) lasting minutes.
!
New PR interval prolongation >280 ms.
!
New prolongation of QTcF to >480 ms (absolute) or by ≥60 ms from baseline.
!
New-onset atrial flutter or fibrillation, with controlled ventricular response rate: ie, 
rate <120 bpm.
!
New-onset type I second-degree (Wenckebach) AV block of >30 seconds’
duration.
!
Frequent PVCs, triplets, or short intervals (<30 seconds) of consecutive ventricular 
complexes.
ECG Findings That May Qualify as SAEs
!
QTcF prolongation >500 ms.
!
New ST-T changes suggestive of myocardial ischemia.
!
New-onset LBBB (QRS complex >120 ms).
!
New-onset right bundle branch block (QRS complex >120 ms).
!
Symptomatic bradycardia.
!
Asystole:
!
In awake, symptom-free participants in sinus rhythm, with documented periods 
of asystole ≥3.0 seconds or any escape rate <40 bpm, or with an escape 
rhythm that is below the AV node; 
!
In awake, symptom-free participants with atrial fibrillation and bradycardia 
with 1 or more pauses of at least 5 seconds or longer; 
!
Atrial flutter or fibrillation, with rapid ventricular response rate: rapid = rate 
>120 bpm.
!
Sustained supraventricular tachycardia (rate >120 bpm) (“sustained” = short 
duration with relevant symptoms or lasting >1 minute).
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!
Ventricular rhythms >30 seconds’ duration, including idioventricular rhythm 
(HR <40 bpm), accelerated idioventricular rhythm (HR 40 bpm to <100 bpm),
and monomorphic/polymorphic ventricular tachycardia (HR >100 bpm [such as
torsades de pointes]).
!
Type II second-degree (Mobitz II) AV block.
!
Complete (third-degree) heart block.
ECG Findings That Qualify as SAEs
!
Change in pattern suggestive of new myocardial infarction.
!
Sustained ventricular tachyarrhythmias (>30 seconds’ duration).
!
Second- or third-degree AV block requiring pacemaker placement.
!
Asystolic pauses requiring pacemaker placement.
!
Atrial flutter or fibrillation with rapid ventricular response requiring cardioversion.
!
Ventricular fibrillation/flutter.
!
At the discretion of the investigator, any arrhythmia classified as an adverse 
experience.
The enumerated list of major events of potential clinical concern are recommended as “alerts” or 
notifications from the core ECG laboratory to the investigator and Pfizer study team, and not to be 
considered as all-inclusive of what to be reported as AEs/SAEs.
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10.9. Appendix 9: Prohibited Concomitant Medications That May Result in DDI
The prohibited concomitant medications listed below should not be taken with PF-07817883
for the period of time at least equal to the required washout period listed in the table, and 
throughout the conduct of the study.
A non-exhaustive list of prohibited and precautionary medications is provided below. If a 
medication is not listed, it should not automatically be assumed it is safe to co-administer. 
Appropriately qualified site staff will review all concomitant medications to determine if they 
are prohibited. 
The Pfizer study team is to be notified of any prohibited medications taken during the study. 
After consulting with the sponsor, the investigator will make a judgment on the ongoing 
participation of any participant with prohibited medication use during the study.
This list of drugs prohibited for potential DDI concerns with the IMP may be revised during
the course of the study with written notification from sponsor, to include or exclude specific 
drugs or drug categories for various reasons (eg, emerging DDI results for the IMP, 
availability of new information in literature on the DDI potential of other drugs).
This is not an all-inclusive list. Site staff should consult with the sponsor or designee with 
any questions regarding potential DDI.
P-gp Substrates
Moderate to Strong 
CYP3A Inhibitor
Moderate to Strong CYP3A inducer
digoxin
amprenavir
apalutamide
dabigatran
amiodarone
asunaprevir and beclabuvir and daclatasvir
aprepitant
avasimibe
atazanavir
bosentan
atazanavir and ritonavir
carbamazepine
berotralstat
cenobamate
boceprevir
dabrafenib
casopitant
efavirenz
ceritinib
elagolix
cimetidine
enzalutamide
ciprofloxacin
etravirine
clarithromycin
ivosidenib
cobicistat
lersivirine
conivaptan
lesinurad
crizotinib
lopinavir
danoprevir and ritonavir
lorlatinib
darunavir
lumacaftor
darunavir and ritonavir
metamizole (dipyrone)
diltiazem
mitapivat
dronedarone
mitotane
duvelisib
modafinil
elvitegravir and ritonavir
nafcillin
erythromycin
pexidartinib
faldaprevir
fedratinib
phenobarbital
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P-gp Substrates
Moderate to Strong 
CYP3A Inhibitor
Moderate to Strong CYP3A inducer
fluconazole
phenytoin
grapefruit juice
rifabutin
grapefruit juice - double strength
rifampin
idelalisib
rifapentine
imatinib
semagacestat
indinavir
sotorasib
indinavir and ritonavir
St. John's wort (Hypericum perforatum)
ipatasertib
talviraline
isavuconazole
telotristat ethyl
istradefylline
thioridazine
itraconazole
tipranavir and ritonavir
josamycin
ketoconazole
lefamulin
letermovir
lonafarnib
lopinavir and ritonavir
mibefradil
mifepristone
nefazodone
nelfinavir
netupitant
nilotinib
ombitasvir and paritaprevir and 
ritonavir and dasabuvir
posaconazole
ravuconazole
ribociclib
ritonavir
saquinavir
saquinavir and ritonavir
Schisandra sphenanthera
telaprevir
telithromycin
tipranavir and ritonavir
tofisopam
treosulfan
troleandomycin
tucatinib
verapamil
voriconazole
voxelotor
Investigators should consult the IB for PF-07817883 for information regarding medication 
that is prohibited for concomitant use. 
Investigators should consult the product label for any other medication used during the study 
for information regarding medication that is prohibited for concomitant use.
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10.10. Appendix 10: Signs and Symptoms Attributable to COVID-19
Table 5.
Signs and Symptoms Attributable to COVID-19
Daily Sign and Symptom Collection13
Entry Criterion #4
Targeted (used for 
study entry)
Daily Signs and 
Symptom Collection
Stuffy or runny nose
X
X
Sore throat
X
X
Cough
X
X
Feeling hot or feverish
X
X
Fatigue (low energy or tiredness)
X
X
Shortness of breath or difficulty breathing 
X
X
Shortness of breath (difficulty breathing) while 
resting
X
Shortness of breath (difficulty breathing) while 
physically active
X
Chest pain
X
Low energy or tiredness after physical activity
X
Difficulty concentrating
X
Chills or shivering
X
X
Muscle or body aches
X
X
Diarrhea (loose or watery stools)
X
X
Nausea (feeling like you wanted to throw up)
X
X
Vomiting (throw up)
X
X
Headache
X
X
Loss of smell 
X
Loss of taste
X
Sustained alleviation of all targeted signs and symptoms is defined as the event occurring on 
the first of 4 consecutive days when all symptoms scored as moderate or severe at study entry 
are scored as mild or absent AND all symptoms scored mild or absent at study entry are 
scored as absent. Missing severity at baseline will be treated as mild.
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The decision to require 4 consecutive days with all targeted symptoms absent or alleviated
was based on exploratory analyses of data from the ACTIV-2/A5401 study which suggested
that this choice (rather than requiring fewer consecutive days) better captured sustained
symptom resolution with low probability of subsequent relapse. The outcome measure
requires 4 consecutive days of targeted symptoms being reported as alleviated or resolved. 
This definition may be updated based on regulatory feedback/interactions and will be 
described in the SAP.
Sustained resolution of all targeted signs and symptoms is defined as the event occurring on 
the first of 4 consecutive days when any symptoms scored as absent, mild, moderate or 
severe at study entry are scored as absent.
Progression to a worsening status for any targeted symptom will be derived 
programmatically based upon increasing severity (ie, the first time any targeted symptom 
worsens after treatment relative to baseline):
Progression to worsening (Yes/No)
Increasing severity
Yes
Not increasing severity
No
Symptom recurrence will be assessed using 2 different definitions:
1. Sponsor definition: Any improvement in targeted COVID-19 signs and symptoms 
that subsequently worsened (total symptom score increased by ≥4).
2. FDA definition: After achieving short symptom recovery (the first day of at least two 
consecutive diary entries where all targeted symptoms are absent), symptom rebound 
is the first day of at least two consecutive diary entries after Day 5 where there is any 
targeted symptom (regardless of severity), or when a subject is hospitalized after 
symptom recovery.
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10.11. Appendix 11: Definition of Viral RNA Rebound
Viral RNA rebound will be assessed using the following FDA-based definition, based upon 
the FDA analysis of the ADMC and ADSL datasets from NDA 217188. This approach 
accounts for the impact of antiviral therapy on early viral RNA decline.
Within the population of Day 5 virologic responders (Day 5 VL <LLOQ or
≥1 log10 copies/mL decline from baseline to Day 5), virologic rebound is defined as:
1) Day 5 VL <LLOQ AND at Day 10, 14, or 21 VL ≥LLOQ;
OR
2) Day 5 RNA ≥LLOQ AND Day 10, 14, or 21 RNA ≥0.5 log10 copies/mL increase 
from Day 5.
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10.12. Appendix 12: Protocol Amendment History
The protocol amendment summary of changes table for the current amendment is located 
directly before the TOC. The protocol amendment summary of changes tables for past 
amendment(s) can be found below:
Amendment 1 (24 March 2023)
Overall Rationale for the Amendment: To update prohibited concomitant medications in 
line with emerging PK data and incorporate regulatory feedback.
Description of Change
Brief Rationale
Section # and Name
Substantial Modification(s)
Addition of PK data from 
PART-5: DDI (midazolam) 
of Study C5091001.
To update the Clinical 
Overview with emerging 
PK data.
Section 2.2.2. Clinical 
Overview
Deletion of text prohibiting 
use of medications highly 
dependent on CYP3A4 for 
clearance with narrow TI 
during study.
PF-07817883 does not 
have CYP3A4 perpetrator 
risk based on midazolam 
DDI.
Section 6.9 Prior and 
Concomitant Therapy
Deletion of text prohibiting 
use of hormonal 
contraceptives during study.
PF-07817883 does not 
have CYP3A4 perpetrator 
risk for enzyme induction.
Section 6.9 Prior and 
Concomitant Therapy
Addition of text to allow 
use of hormonal 
contraceptives during study.
PF-07817883 does not 
have CYP3A4 perpetrator 
risk.
Appendix 4
Addition of inclusion 
criterion #5, addition of 
new exclusion criterion #2, 
revision of exclusion 
criterion #11 and 
clarification of therapy 
permitted and prohibited 
during the study.
To address comments 
received from the FDA.
Section 1.1 Synopsis, Section 
5.1 Inclusion Criteria, Section 
5.2 Exclusion Criteria, Section 
6.9 Prior and Concomitant 
Therapy and Section 7.1 
Discontinuation of Study 
Intervention
Addition of assessments for 
viral RNA rebound and 
symptom recurrence as 
exploratory objectives and 
endpoints in Section 3. 
Corresponding addition of 
definitions for symptom 
recurrence to Appendix 10 
To address comments 
received from the FDA.
Section 3 Objectives, 
Endpoints, and Estimands, 
Section 10.10 Appendix 10 
Signs and Symptoms 
Attributable to COVID-19 and 
Section 10.11 Appendix 11 
Definitions of Viral RNA 
Rebound.
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Description of Change
Brief Rationale
Section # and Name
and addition of definitions 
for viral RNA rebound to 
new Appendix 11.
Addition of SARS-CoV-2 
RNA level assessments at 
Day 21 and Day 33, with 
corresponding edit of Day 
21 visit from “T” to “S/P” 
and Day 33 visit from “T” 
to “S/P/T”.
To address comments 
received from the FDA.
Section 1.3 SoA SARS-CoV-2 
RNA level assessment (NP) 
and Study Visit Location
Addition of targeted 
physical exam and vital 
signs assessment at Day 21 
site visit and Day 33 visit if 
participant is still 
symptomatic.
To address comments 
received from the FDA.
Section 1.3 SoA Targeted 
physical examination and 
Vital signs
Addition of instructions to 
sites for collecting 
unscheduled NP samples in 
the case of symptom 
worsening or recurrence.
To address comments 
received from the FDA.
Section 8.7.5 Viral RNA 
Level Assessments
Addition of a PK sample by 
TASSO micro-sampling 
before administration of 
second dose of PF-
07817883.
To address comments 
received from the FDA.
Section 1.3 SoA PK micro-
sampling 
Addition of optional Day 
21 assessment.
To address comments 
received from the FDA.
Section 1.3 SoA Retained 
research samples for 
biomarkers (Prep B2.5, prep 
R1)
Addition of AE assessments 
at Days 2 and 4.
AEs will be assessed if 
optional Day 2 and 4 visits 
occur.
Section 1.3 SoA Serious and 
nonserious AE monitoring
Removed need for 
participant to check 
temperature.
Fever will be captured as 
part of the daily signs and 
symptoms collection 
through the “feeling hot or 
feverish” symptom. To 
avoid duplication of data, 
the participant will not 
measure their temperature.
Section 8.2.3 Daily Signs and 
Symptoms of COVID-19 and 
Section 8.3.4.4 At-Home 
Devices for Vital Signs.
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Description of Change
Brief Rationale
Section # and Name
Removed recording of 
documented fever in Daily 
Signs and Symptom 
Collection and as part of 
Entry Criterion. Removed
correlating footnote.
Fever will be captured as 
part of the daily signs and 
symptoms collection 
through the “feeling hot or 
feverish” symptom. To 
avoid duplication of data, 
the participant will not 
measure their temperature.
Section 10.10 Appendix 10 
Signs and Symptoms 
Attributable to COVID-19
Removed need for 
participants to be supplied 
with a pulse oximeter.
Oxygen saturation will be 
checked during all in-
person site visits.
Section 8.3.4. Vital Signs and 
Section 8.3.4.4 At-Home 
Devices for Vital Signs
Addition of eGFR
(combined Scr+Scys) and 
albumin assessments and 
edits to collect cystatin C 
post-baseline at each lab 
assessment.
Updates to kidney function 
assessments as per 
guidance from Pfizer 
Kidney Safety Council 
recommendation.
Section 10.2 Appendix 2 
Clinical Laboratory Tests
Nonsubstantial Modification(s)
Added text from Exclusion 
Criterion #15 into Section 
1.3 SoA Notes for Safety 
Laboratory Assessments 
row.
Clarification of this text is 
to provide guidance 
surrounding laboratory 
assessments.
Section 1.3 SoA Safety 
Laboratory Assessments
Edited “Study Visit 
Location” for Day 2 and 4 
optional visits from “NA” 
to “T”.
Clarification that these 
optional visits may be 
conducted by telehealth.
Section 1.3 SoA Study Visit 
Location
Addition of “Day 1” to the 
SoA Notes column.
Clarification that post-dose 
ECGs should be performed 
within 30 to 90 mins post-
dose on Day 1.
Section 1.3 SoA 12-lead ECG
Edited “NP” to “nasal”.
Clarification that a nasal 
sample is required for the 
selected RAT kit used at 
screening.
Section 1.1 Synopsis, Section 
1.3 SoA, Section 5.1 Inclusion 
Criteria and Section 8.7.1 
Rapid Antigen Assessments
Deletion of “predicted" and  
“preliminary” for toxicity 
margin text and edit “total” 
to “unbound” for Cmax and 
AUC24 values.
Clarification edits to align 
with Investigators 
Brochure Version 2 
updates.
Section 2.2.1 Nonclinical 
Studies of PF-07817883
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Description of Change
Brief Rationale
Section # and Name
Addition of description on 
use of PK/PD modeling and 
simulation results.
Clarification that PK/PD 
modeling and simulation 
results would only impact 
dose selection decisions at 
a program level and not the 
protocol level [ie, current 
study]).
Section 9.6.1 Early PK/PD 
Unblinding Plan
Addition of sponsor’s 
address.
To comply with new 
regulatory requirements.
Title page
Edits throughout Section 
10.1 Appendix 1.
To comply with new 
regulatory requirements.
Section 10.1 Appendix 1 
Regulatory, Ethical and Study 
Oversight Considerations
Minor edits to clarify 
protocol text and correct 
minor errors and typos from 
previous versions.
To clarify protocol text and 
correct inadvertent errors.
Several sections throughout
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10.13. Appendix 13: Abbreviations
The following is a list of abbreviations that may be used in the protocol.
Abbreviation
Term
%CV
percent coefficient of variation
μM
micromolar
3CL
3C-like
Abs
absolute
AE
adverse event
AKI
acute kidney injury
ALT
alanine aminotransferase
ARDS
acute respiratory distress syndrome
AST
aspartate aminotransferase
AUC24
area under the concentration-time curve from time zero to 24 hours 
(1 day)
AV
atrioventricular
AxMP
auxiliary medicinal product
∀-hCG
∀-human chorionic gonadotropin
BID
twice daily
BP
blood pressure
bpm
beats per minute
BUN
blood urea nitrogen
CAR
chimeric antigen receptor
CFR
Code of Federal Regulations
CI
confidence interval
CIOMS
Council for International Organizations of Medical Sciences
CK
creatine kinase
CKD-EPI
chronic kidney disease epidemiology 
CLr
renal clearance
Cmax
maximum observed concentration
CO2
bicarbonate
CONSORT
Consolidated Standards of Reporting Trials
COVID-19
coronavirus disease 2019
CPAP
continuous positive airway pressure
CRF
case report form
CRO
contract research organization
CSR
Clinical Study Report
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Abbreviation
Term
CT
clinical trial
CTIS
Clinical Trial Information System
Ctrough
drug concentration observed at the last planned timepoint prior to
dosing
CYP
cytochrome P450
CYP3A4
cytochrome P450 3A4
DAIDS
Division of AIDS
DCT
data collection tool
DDI
drug-drug interaction 
DICI
drug-induced creatinine increase
DIKI
drug-induced kidney injury
DILI
drug-induced liver injury
difTarget
difference in response between the highest dose (600 mg q12h) and 
placebo
dNHBE
differentiated normal human bronchial epithelial cells
DU
dispensable unit
E1
primary analysis estimand
E2
estimand for supplementary analyses
EC
ethics committee
EC50
drug concentration at which 50% inhibition of viral replication is
observed; concentration required for 50% effect
EC90
drug concentration at which 90% inhibition of viral replication is
observed; concentration required for 90% effect
ECC
emergency contact card
ECG
electrocardiogram or electrocardiography
eCrCl
estimated creatinine clearance
eCRF
electronic case report form
EDB
exposure during breastfeeding
eDiary
electronic diary
EDP
exposure during pregnancy
eGFR
estimated glomerular filtration rate
EMA
European Medicines Agency
EOS
end of study
EOT
end of treatment
ePRO
electronic patient reported outcomes
eSAE
electronic serious adverse event
ET
early termination
EU
European Union
EUA
Emergency Use Authorization
EudraCT
European Union Drug Regulating Authorities Clinical Trials 
(European Clinical Trials Database)
FAS
full analysis set
FDA
Food and Drug Administration
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Abbreviation
Term
FE
food effect
FIH
first-in-human
FSH
follicle-stimulating hormone
fu
fraction unbound
F/U
follow-up
GCP
Good Clinical Practice
GGT
gamma-glutamyl transferase
HCoV
human coronavirus
HCP
healthcare provider
HCT
hematopoietic cell transplantation
HIV
human immunodeficiency virus
hr
hour
HR
heart rate
HRT
hormone replacement therapy
hs-CRP
high-sensitivity C-reactive protein
IB
Investigator’s Brochure
ICD
informed consent document
ICH
International Council for Harmonisation of Technical Requirements 
for Pharmaceuticals for Human Use
ICU
intensive care unit
ID
identification
IgG
immunoglobulin G
IgM
immunoglobulin M
IMP
investigational medicinal product
IND
Investigational New Drug
INR
international normalized ratio
IP
investigational product
IPAL
Investigational Product Accountability Log
IPM
investigational product manual
IRB
Institutional Review Board
IRC
internal review committee
IRT
Interactive Response Technology
IV
intravenous
KDIGO
Kidney Disease: Improving Global Outcomes
KO
knock out
LBBB
left bundle branch block
LDH
lactate dehydrogenase
LFT
liver function test
LLOQ
lower limit of quantitation
LS
least-squares
mAb
monoclonal antibody
MAD
multiple ascending dose
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Abbreviation
Term
ME
metabolism and excretion
MERS
Middle East Respiratory Syndrome
MFAS
modified full analysis set
mg
milligram
mIU/mL
milli-international units per milliliter
mL
milliliter
mm3
millimeter cubed
MMRM
mixed model for repeated measures
MOA
mechanism of action
Mpro
main protease
MQI
medically qualified individual
ms
milliseconds
MTD
maximum tolerated dose
NA
not applicable
NDA
New Drug Application
NIMP
noninvestigational medicinal product
NOAEL
no observed adverse effect level
NP
nasopharyngeal
NR
not reportable
PD
pharmacodynamic(s)
P-gp
p-glycoprotein
PI
principal investigator
PK
pharmacokinetic(s)
PR
pulse rate
PRO
patient reported outcomes
PSSA
Pfizer's Serious Adverse Event Submission Assistant
PT
prothrombin time
PVC
premature ventricular contraction
q12h
every 12 hours
QTc
corrected QT interval
QTcF
QTc corrected using Fridericia’s formula
QTL
quality tolerance limit
qual
qualitative
RAT
rapid antigen testing
rBA
relative bioavailability
RBC
red blood cell
RNA
ribonucleic acid
RT-PCR
reverse transcriptase–polymerase chain reaction
[S]
investigational site
SAD
single ascending dose
SAE
serious adverse event
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Abbreviation
Term
SAP
Statistical Analysis Plan
SARS-CoV-1
severe acute respiratory syndrome coronavirus 1
SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
SAS
safety analysis set
Screat
serum creatinine
Scys
serum cystatin C
SD
single dose
SE
standard error, supratherapeutic exposure
SoA
schedule of activities
SoC
standard of care
SOP
standard operating procedure
SRSD
Single Reference Safety Document
SUSAR
Suspected Unexpected Serious Adverse Reaction
[T]
telehealth visit
T bili
total bilirubin
TEAE
treatment-emergent adverse event
TMPRSS2
transmembrane serine protease 2
TNF
tumor necrosis factor
ULN
upper limit of normal
US
United States
UTI
urinary tract infection
VeroE6
monkey kidney cells E6
VL
viral load
WBC
white blood cell
WHO
World Health Organization
WOCBP
woman/women of childbearing potential
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11. REFERENCES
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