A PHASE 1, OPEN-LABEL, RANDOMIZED, SINGLE-DOSE, CROSSOVER STUDY TO ESTIMATE THE RELATIVE BIOAVAILABILITY OF PF-07321332 FOLLOWING ORAL ADMINISTRATION OF 4 DIFFERENT FORMULATIONS RELATIVE TO THE COMMERCIAL TABLET FORMULATION IN HEALTHY ADULT PARTICIPANTS UNDER FASTED CONDITIONS
Phase: PHASE1
Conditions: Bioavailability
Sponsor: Pfizer

PF-07321332 
Protocol C4671008
Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
Page 1
A PHASE 1, OPEN-LABEL, RANDOMIZED, SINGLE-DOSE, CROSSOVER STUDY 
TO ESTIMATE THE RELATIVE BIOAVAILABILITY OF PF-07321332 
FOLLOWING ORAL ADMINISTRATION OF 4 DIFFERENT FORMULATIONS 
RELATIVE TO THE COMMERCIAL TABLET FORMULATION IN HEALTHY 
ADULT PARTICIPANTS UNDER FASTED CONDITIONS
Study Intervention Number:
PF-07321332
Study Intervention Name:
N/A
US IND Number:
EudraCT Number:
N/A
ClinicalTrials.gov ID: 
N/A
Protocol Number:
C4671008
Phase:
1
Brief Title: A Phase 1 Relative Bioavailability Study of 4 Different Formulations of 
PF-07321332 Relative to the Commercial Tablet Formulation in Healthy Participants
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.
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Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
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Document History
Document
Version Date
Protocol Amendment 1
08 February 2022
Original protocol
26 January 2022
This amendment incorporated all revisions to date, including amendments made at the 
request of country health authorities and IRBs/ECs and any global protocol administrative 
clarification letter, based on requested changes by digital medical team, PCRU and study 
team.
Protocol Amendment Summary of Changes Table
Amendment 1 (07 February 2022)
Overall Rationale for the amendment: This study is being amended to remove digital 
wearables, include one additional treatment arm of SDD alone at 300 mg and change dose of 
Treatment D from 150 mg to 300 mg, and address a comment from the PCRU to remove 
phosphate/phosphorous test from the clinical laboratory tests. Detailed changes are 
summarized below in a tabular form.
Section # and Name
Description of Change
Brief Rationale

Section 1.1 (Synopsis);

Section 1.3 (SoA)

Section 9.3.3 (Other Safety 
Analyses)

Section 10.8 (Abbreviations)
Removed RR (respiratory rate) from safety 
analysis.
PF-07321332 or 
Ritonavir are not 
giving central 
respiratory
depression and are 
removed based upon 
team’s agreement. 

Section 1.3 (SoA);

Section 3 
(Tertiary/Exploratory 
Objective);

Section 8.2.7 (Digital Health 
Technology);

Section 8.9 (Digital Health 
Technology [DHT]);

Section 9.3.4 (Other 
analyses);

Section 10.8 (Abbreviations)
Removed digital health technology (digital 
wearables) related sections.
IQVIA has stated 
that they are not able 
to meet the study 
timelines. 

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Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
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Section # and Name
Description of Change
Brief Rationale

Section 1.1 (Synopsis);

Section 1.3 (SoA);

Section 2.1 (Study 
Rationale);

Section 4.1 (Overall design);

Section 4.2 (Scientific 
Rationale for Study Design);

Section 4.3 (Justification for 
Dose);

Section 6.1 (Study 
Interventions administered);

Section 6.1.1 
(Administration)
Revisions on Treatment D SDD 150 mg to 
300 mg.
Added another treatment arm of PF-
07321332 300 mg SDD in related sections.
Added Treatment E: PF-07321332 300 mg 
(SDD suspension) as Test formulation 4 in 
related sections.
Added Period 5 in related study design 
sections to include SDD 300 mg arm.
Made revisions on duration of the study 
from 11 weeks to 12 weeks.
Made revisions on Treatment sequences.
To explore 
alternative 
formulation.

Section 1.1 (Synopsis);

Section 3 (Objectives and 
endpoints)
Made revisions To estimate the rBA of the 
PF-07321332 SDD suspension 
formulation/ritonavir 300/100 mg compared 
to the PF-07321332 commercial tablet 
formulation (2 × 150 mg)/ritonavir 
300/100 mg under fasted conditions as study 
primary objective.
Added To estimate the rBA of the 
PF-07321332 SDD suspension formulation 
(300 mg) without ritonavir compared to the 
PF-07321332 commercial tablet 
formulation (2 × 150 mg) under fasted 
conditions as study primary objective and
Plasma PF-07321332 PK parameters: 
AUClast, AUCinf (if data permits) and 
Cmax as primary endpoints and make 
revisions in relevant paragraphs.
To explore SDD as 
an alternative 
formulation.

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Section # and Name
Description of Change
Brief Rationale
•
Section 2.2.3 (Nonclinical 
Safety)
PF-07321332-related nonadverse, test 
article-related clinical findings included 
sporadic occurrence of emesis with slight 
body weight decreases in monkeys in the 1-
month study (Newly added). In rats, 
monitorable and reversible clinical 
pathology findings included those possibly 
suggestive of low-grade inflammation 
 
or alterations 
in the coagulation pathways
without clinical or microscopic 
correlates. In monkeys, monitorable and 
reversible clinical pathology findings 
included increase in ALT and/or AST and 
increase in fibrinogen at the high dose in 
the 1-month study without clinical or 
microscopic correlates (Newly added).
 
In rats administered 1000 
mg/kg/day, lower mean absolute and relative 
heart weights (females) and higher mean 
(revised) liver weights 
(both sexes) were observed relative to 
controls.
Per updates from IB 
Version 4.0.
•
Section 2.3 (Benefit/Risk 
Assessment)
SRSD for ritonavir is changed to the IB per
updates in IB.
Per updates from IB 
Version 4.0.
•
Section 4.3 (Justification for 
Dose)
Rationale of adding SDD formulation (with 
or without ritonavir) was added.
To explore SDD as 
an alternative 
formulation.
•
Section 5.2 Exclusion 
Criteria
Appendectomy was removed from #4, 
HBcAb was added to #5.
Per Comments from 
PCRU.
•
Section 8 (Study 
Assessments and 
Procedures)
Total volume of blood sampling changed 
from 290 mL to 350 mL.
Updates based upon 
study design change: 
to explore SDD as an 
alternative 
formulation.
•
Section 9.3.2 (Statistical 
Methods for PK data)
•
Secction 9.5 (Sample Size 
Determination)
Revisions made based on additional 
treatment E and additional treatment 
sequences.
Updates based upon 
study design change: 
to explore SDD as an 
alternative 
formulation.
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Section # and Name
Description of Change
Brief Rationale

Section 10.2 (Clinical 
Laboratory Test)
Removed Phosphate/phosphorus in Table 3, 
Chemistry column.
Per Comments from 
PCRU: this will not 
be routinely done, 
and should be 
removed.
Minor editorial changes throughout the document.

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Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
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TABLE OF CONTENTS
LIST OF TABLES...................................................................................................................10
1. PROTOCOL SUMMARY...................................................................................................11
1.1. Synopsis ..................................................................................................................11
1.2. Schema ....................................................................................................................15
1.3. Schedule of Activities .............................................................................................16
2. INTRODUCTION ...............................................................................................................19
2.1. Study Rationale .......................................................................................................19
2.2. Background .............................................................................................................19
2.2.1. Nonclinical Pharmacology..........................................................................19
2.2.2. Nonclinical Pharmacokinetics and Metabolism .........................................20
2.2.3. Nonclinical Safety ......................................................................................20
2.2.4.1. Safety Overview........................................................................21
2.2.4.2. Summary of PF-07321332 Pharmacokinetics in Human..........22
2.3. Benefit/Risk Assessment.........................................................................................23
3. OBJECTIVES AND ENDPOINTS.....................................................................................24
4. STUDY DESIGN.................................................................................................................24
4.1. Overall Design.........................................................................................................24
4.2. Scientific Rationale for Study Design.....................................................................26
4.2.1. Choice of Contraception/Barrier Requirements .........................................27
4.2.2. Collection of Retained Research Samples..................................................27
4.3. Justification for Dose ..............................................................................................27
4.4. End of Study Definition ..........................................................................................27
5. STUDY POPULATION......................................................................................................27
5.1. Inclusion Criteria.....................................................................................................28
5.2. Exclusion Criteria....................................................................................................28
5.3. Lifestyle Considerations..........................................................................................31
5.3.1. Meals and Dietary Restrictions...................................................................31
5.3.2. Caffeine, Alcohol, and Tobacco .................................................................32
5.3.3. Activity .......................................................................................................32
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5.3.4. Contraception..............................................................................................32
5.4. Screen Failures ........................................................................................................33
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY.................................33
6.1. Study Intervention(s) Administered........................................................................33
6.1.1. Administration............................................................................................33
6.2. Preparation, Handling, Storage, and Accountability...............................................34
6.2.1. Preparation and Dispensing........................................................................35
6.3. Measures to Minimize Bias: Randomization and Blinding.....................................35
6.3.1. Allocation to Study Intervention ................................................................35
6.4. Study Intervention Compliance...............................................................................35
6.5. Dose Modification...................................................................................................36
6.6. Continued Access to Study Intervention After the End of the Study......................36
6.7. Treatment of Overdose............................................................................................36
6.8. Concomitant Therapy..............................................................................................36
6.8.1. Rescue Medicine.........................................................................................37
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL...........................................................................37
7.1. Discontinuation of Study Intervention ....................................................................37
7.1.1. ECG Changes..............................................................................................37
7.1.2. Potential Cases of Acute Kidney Injury .....................................................38
7.1.3. Stopping Rules............................................................................................38
7.2. Participant Discontinuation/Withdrawal From the Study.......................................39
7.2.1. Withdrawal of Consent...............................................................................40
7.3. Lost to Follow up ....................................................................................................40
8. STUDY ASSESSMENTS AND PROCEDURES...............................................................40
8.1. Efficacy Assessments..............................................................................................41
8.2. Safety Assessments .................................................................................................42
8.2.1. Physical Examinations................................................................................42
8.2.2. Vital Signs ..................................................................................................42
8.2.2.1. Respiratory Rate........................................................................43
8.2.2.2. Temperature ..............................................................................43
8.2.3. Electrocardiograms.....................................................................................43

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8.2.4. Clinical Safety Laboratory Assessments ....................................................44
8.2.5. COVID-19 Specific Assessments...............................................................44
8.2.6. Pregnancy Testing ......................................................................................44
8.3. Adverse Events, Serious Adverse Events, and Other Safety Reporting .................45
8.3.1. Time Period and Frequency for Collecting AE and SAE Information.......45
8.3.1.1. Reporting SAEs to Pfizer Safety...............................................46
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF...................46
8.3.2. Method of Detecting AEs and SAEs ..........................................................46
8.3.3. Follow-Up of AEs and SAEs......................................................................46
8.3.4. Regulatory Reporting Requirements for SAEs...........................................47
8.3.5. Environmental Exposure, Exposure During Pregnancy or 
Breastfeeding, and Occupational Exposure.....................................................47
8.3.5.1. Exposure During Pregnancy......................................................47
8.3.5.2. Exposure During Breastfeeding ................................................49
8.3.5.3. Occupational Exposure .............................................................49
8.3.6. Cardiovascular and Death Events...............................................................49
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs..............................................................................50
8.3.8. Adverse Events of Special Interest.............................................................50
8.3.8.1. Lack of Efficacy........................................................................50
8.3.9. Medical Device Deficiencies......................................................................50
8.3.10. Medication Errors.....................................................................................50
8.4. Pharmacokinetics ....................................................................................................51
8.4.1. Plasma for Analysis of PF-07321332 and Ritonavir..................................51
8.5. Genetics...................................................................................................................52
8.5.1. Specified Genetics ......................................................................................52
8.5.2. Retained Research Samples for Genetics ...................................................52
8.6. Biomarkers ..............................................................................................................52
8.6.1. Specified Gene Expression (RNA) Research .............................................52
8.6.2. Specified Protein Research.........................................................................52
8.6.3. Specified Metabolomic Research ...............................................................52
8.6.4. Retained Research Samples for Biomarkers...............................................52

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8.7. Immunogenicity Assessments.................................................................................53
8.8. Health Economics ...................................................................................................53
9. STATISTICAL CONSIDERATIONS ................................................................................53
9.1. Statistical Hypotheses .............................................................................................53
9.2. Analysis Sets ...........................................................................................................53
9.3. Statistical Analyses .................................................................................................54
9.3.1. Pharmacokinetic Analyses..........................................................................54
9.3.1.1. Derivation of Pharmacokinetic Parameters...............................54
9.3.2. Statistical Methods for PK Data .................................................................55
9.3.3. Other Safety Analyses ................................................................................55
9.3.4. Other Analyse(s).........................................................................................56
9.4. Interim Analyses .....................................................................................................56
9.5. Sample Size Determination.....................................................................................56
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS..........................................................................................................58
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations...............58
10.1.1. Regulatory and Ethical Considerations ....................................................58
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP.........................................................................58
10.1.2. Informed Consent Process ........................................................................59
10.1.3. Data Protection .........................................................................................60
10.1.4. Committees Structure ...............................................................................60
10.1.4.1. Data Monitoring Committee ...................................................60
10.1.5. Dissemination of Clinical Study Data ......................................................60
10.1.6. Data Quality Assurance ............................................................................61
10.1.7. Source Documents....................................................................................62
10.1.8. Study and Site Start and Closure ..............................................................63
10.1.9. Publication Policy.....................................................................................64
10.1.10. Sponsor’s Qualified Medical Personnel .................................................64
10.2. Appendix 2: Clinical Laboratory Tests .................................................................66
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting .....................................................................67

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10.3.1. Definition of AE .......................................................................................67
10.3.2. Definition of an SAE ................................................................................68
10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During 
the Active Collection Period............................................................................69
10.3.4. Reporting of SAEs....................................................................................73
10.4. Appendix 4: Contraceptive and Barrier Guidance ................................................74
10.4.1. Male Participant Reproductive Inclusion Criteria....................................74
10.4.2. Female Participant Reproductive Inclusion Criteria.................................74
10.4.3. Woman of Childbearing Potential ............................................................75
10.4.4. Contraception Methods.............................................................................76
10.5. Appendix 5: Genetics............................................................................................78
10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments .......79
10.7. Appendix 7: ECG Findings of Potential Clinical Concern ...................................81
10.8. Appendix 8: Abbreviations ...................................................................................83
11. REFERENCES ..................................................................................................................87
LIST OF TABLES
Table 1.
Randomized Treatment Sequences...........................................................25
Table 2.
Plasma PF-07321332 PK Parameters Definitions....................................54
Table 3.
Protocol-Required Safety Laboratory Assessments .................................66

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1. PROTOCOL SUMMARY 
1.1. Synopsis 
Brief Title: A Phase 1 Relative Bioavailability Study of 4 Different Formulations of 
PF-07321332 Relative to the Commercial Tablet Formulation in Healthy Participants.
Rationale
PF-07321332 is a potent and selective inhibitor of the SARS-CoV-2 3CL protease that is 
currently being developed as an oral treatment of COVID-19. Ritonavir is a strong CYP3A4 
inhibitor being used to inhibit the metabolism of PF-07321332 in order to increase plasma 
concentrations of PF-07321332 to values that are anticipated to be efficacious. 
 
 
 
 
 
The purpose of this study is to estimate the rBA of PF-07321332 slower dissolution and 
larger particle size tablet formulations and SDD extemporaneous suspension formulation 
relative to the commercial tablet formulation in healthy adult participants under fasted 
condition.
This study objective is to estimate the rBA of single doses of PF-07321332 300 mg slower 
dissolution tablet formulation and larger particle size tablet formulation with ritonavir 
100 mg compared to PF-07321332 300 mg doses commercial tablet formulation with 
ritonavir 100 mg. An additional objective of this study is to estimate the rBA of PF-
07321332 300 mg doses SDD extemporaneous suspension formulation administered with
and without 100 mg of ritonavir compared to PF-07321332 300 mg doses commercial tablet 
formulation administered with ritonavir 100 mg.
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Objectives and Endpoints 
Primary Objective: 
Primary Endpoint: 

To estimate the rBA of the PF-07321332 slower
dissolution tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg compared to 
the PF-07321332 commercial tablet formulation
(2 × 150 mg)/ritonavir 300/100mg under fasted
conditions.

To estimate the rBA of the PF-07321332 larger 
particle size tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg compared to 
the PF-07321332 commercial tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg under fasted
conditions.

To estimate the rBA of the PF-07321332 SDD 
suspension formulation/ritonavir 300/100 mg 
compared to the PF-07321332 commercial tablet 
formulation (2 × 150 mg)/ritonavir 300/100 mg
under fasted conditions.

To estimate the rBA of the PF-07321332 SDD 
suspension formulation (300 mg) without ritonavir 
compared to the PF-07321332 commercial tablet 
formulation (2 × 150 mg)/ritonavir 300/100 mg
under fasted conditions.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.
Secondary Objective: 
Secondary Endpoints: 

To evaluate the safety and tolerability of 
PF-07321332/ritonavir in healthy participants.

Assessment of TEAEs, clinical laboratory 
abnormalities, vital signs, physical 
examinations, and 12-lead ECGs.
Tertiary/Exploratory Objective:
Tertiary/Exploratory Endpoints:

To characterize the PK of PF-07321332 after
single oral doses of different formulations.

Plasma PF-07321332 PK parameters: t½ (if 
data permits), CL/F, Vz/F (if data permits) and 
Tmax of PF-07321332.
Overall Design
Brief Summary
This is a Phase 1, open-label, single-dose, randomized, crossover study in healthy adult 
participants to evaluate rBA of PF-07321332 slower dissolution tablet formulation with 
ritonavir 100 mg (Test formulation 1), larger particle size tablet formulation with ritonavir
100 mg (Test formulation 2), SDD 300 mg suspension formulation with ritonavir 100 mg 
(Test formulation 3), and SDD 300 mg suspension formulation without ritonavir (Test 

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formulation 4) compared to the PF-07321332 commercial tablet formulation with ritonavir 
100 mg (Reference formulation) under fasted condition. 
Approximately 12 healthy male and/or female participants will be randomized to ensure at 
least 10 participants will complete the study. Participants who discontinue from the study for 
non-safety reasons may be replaced at the sponsor’s discretion in collaboration with the 
Investigator.
Healthy participants will be screened to determine eligibility within 28 days prior to study 
treatment. Medical history and results of physical examination, vital signs, 12-lead ECGs, 
and clinical laboratory evaluations will determine eligibility. Eligible participants will be 
admitted to the CRU on Day -1 and will be confined in the CRU until discharge which is 
Day 4 of Period 5.
On Day 1 of each period, participants will receive a single dose of study intervention 
PF-07321332 along with or without 100 mg of ritonavir as per the randomization schedule.
Additional doses of ritonavir 100 mg approximately at -12, and 12 hours relative to the dose 
of PF-07321332 will be administered in treatment A, B, C and D. Study treatments will be 
administered with approximately 240 mL of ambient temperature water under fasted
conditions (overnight fast and no food until 4 hours after dosing). Serial PK samples will be 
collected up to 72 hours post dose. Participants will be discharged from the CRU on Period 5, 
Day 4 following completion of all assessments.
If a participant has any clinically significant, study related abnormalities at the conclusion of 
a scheduled inpatient portion of the study, the Pfizer medical monitor (or designated 
representative) should be notified and the participant may be asked to remain in the CRU 
until such abnormalities are deemed not clinically significant, or it is safe for outpatient 
follow-up.
A safety follow-up call will be made to participants approximately 28 to 35 days from 
administration of the final dose of study intervention.
Number of Participants
Approximately 12 participants will be randomly assigned to study intervention such that 
approximately 2 participants will be enrolled into 1 of 6 sequences.
Note: "Enrolled" means a participant'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 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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Intervention Groups and Duration
Each enrolled participant will participate in 5 study periods to receive 5 different treatments 
according to the sequence determined by randomization: 

Treatment A: PF-07321332 300 mg (2 × 150 mg commercial tablets)/100 mg 
ritonavir 

Treatment B: PF-07321332 300 mg (2 × 150 mg slow dissolution tablets)/100 mg 
ritonavir 

Treatment C: PF-07321332 300 mg (2 × 150 mg large particle size tablets)/100 mg 
ritonavir 

Treatment D: PF-07321332 300 mg (SDD suspension)/100 mg ritonavir

Treatment E: PF-07321332 300 mg (SDD suspension)
Participants will be randomly assigned to 1 of 6 sequences as follows: 
Treatment
Sequence
Period 1
Period 2
Period 3
Period 4
Period 5
Sequence 1 (N =2)
Treatment A
Treatment B
Treatment C
Treatment D
Treatment E
Sequence 2 (N =2)
Treatment B
Treatment C
Treatment A
Treatment D
Treatment E
Sequence 3 (N =2)
Treatment C
Treatment A
Treatment B
Treatment D
Treatment E
Sequence 4 (N =2)
Treatment A
Treatment C
Treatment B
Treatment E
Treatment D
Sequence 5 (N =2)
Treatment B
Treatment A
Treatment C
Treatment E
Treatment D
Sequence 6 (N =2)
Treatment C
Treatment B
Treatment A
Treatment E
Treatment D
Participants will be discharged on Day 4 of Period 5, following completion of all 
assessments. 
The total planned duration of participation from the Screening visit to the last Follow-up 
phone call, is approximately 12 weeks.
Data Monitoring Committee or Other Independent Oversight Committee: No
Statistical Methods
Natural log transformed AUCinf (if data permits), AUClast and Cmax will be analyzed using a 
mixed effect model with sequence, period and treatment as fixed effects and participant 
within a sequence as a random effect.

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Sample Size Determination
A sample size of 12 participants will be sufficient to provide a reliable estimate of rBA and 
intrasubject variability of PF-07321332. Participants who withdraw from the study may be 
replaced at the discretion of the investigator upon consultation with the sponsor.
Pharmacokinetics Analysis
The PK concentration population is defined as all participants who take at least 1 dose of 
study intervention and in whom at least 1 concentration value is reported.
The PK parameter analysis population is defined as all participants who take at least 1 dose 
of study intervention and in whom at least 1 of the PK parameters of primary interest are 
reported.
PK parameters for PF-07321332 will be analyzed using standard noncompartmental method 
of analysis. Actual PK sampling times will be used in the derivation of PF-07321332 PK 
parameters when available, otherwise nominal times will be used. The PF-07321332 plasma 
PK parameters will be summarized descriptively by treatment and Day. Plasma 
concentrations will be listed and summarized descriptively by treatment, and nominal PK 
sampling time. Individual participant and summary profiles (mean and median plots) of the 
plasma concentration time data will be plotted using actual and nominal times, respectively. 
To estimate relative bioavailability, natural log transformed AUCinf (if data permits), AUClast
and Cmax values of PF-07321332 will be analyzed using a mixed effect model with sequence, 
period and treatment as fixed effect and participant within sequence as a random effect.
Estimates of the adjusted mean differences (Test-Reference) and corresponding 90% CIs will 
be obtained from the model. The adjusted mean differences and 90% CIs for the differences 
will be exponentiated to provide estimates of the ratio of adjusted geometric means 
(Test/Reference) and 90% CI for the ratios.
Safety Analysis
AEs, ECGs, BP, PR, and safety laboratory data will be reviewed and summarized on an 
ongoing basis during the study to evaluate the safety of participants. Any clinical laboratory, 
ECG, BP, and PR abnormalities of potential clinical concern will be described. Safety data 
will be presented in tabular and/or graphical format and summarized descriptively, where 
appropriate.
1.2. Schema
Not Applicable.

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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. 
SoA:
Visit Identifier
Abbreviations used in this table may be 
found in Appendix 8
Screeninga
Periods 1-5
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1b
Day 1
Day 
2
Day 3 Day 4 28-35 Daysc
Hours After Dose
0
0.5
1
1.5
2
2.5
3
4
6
8
12
16
24
48
72
Informed consent
X
CRU Confinementd
X
®
®
®
®
®
®
®
®
®
®
®
®
®
®
Xe
Inclusion/exclusion criteria
X
X
Medical/medication history (update)f
X
X
Demographyg
X
Physical examh
X
X
Safety laboratoryi
X
X
Xe
X
FSHj
X
Urine drug testingk
X
X
Serology: HBsAg, HBsAb, HBcAb, 
HCVAb, and HIVl
X
Pregnancy test (WOCBP only)
X
X
Xe
X
Contraception checkm
X
X
X
12-lead ECG (single)n
X
Xo
Xo
X
Vital signs (BP/PR)p
X
X
X
X
X
Xo
X
COVID-19 questionnaireq
X
X
COVID-19 testingr
X
X
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Visit Identifier
Abbreviations used in this table may be 
found in Appendix 8
Screeninga
Periods 1-5
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1b
Day 1
Day 
2
Day 3 Day 4 28-35 Daysc
Hours After Dose
0
0.5
1
1.5
2
2.5
3
4
6
8
12
16
24
48
72
COVID-19 check temperatures
X
X
PF-07321332 dosingt
X
Ritonavir dosingu
X
X
X
PK Blood Sampling for 
PF-07321332v
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
 
Other Retained Research Samples 
(Prep B2)w
X
Serious and nonserious AE 
monitoring
X
®
®
®
®
®
®
®
®
®
®
®
®
®
®
®
®
X
X
Concomitant treatments
X
X
X
®
®
®
®
®
®
®
®
®
®
®
®
®
X
X
CRU discharge
Xe
a.
Screening will be performed within 28 days prior to the first dose of PF-07321332/ritonavir. 
b.
This is applicable for Period 1 only, unless particularly specified.
c.
Follow-up will contact may occur via telephone contact and must occur 28 to 35 days from administration of the final dose of study intervention.
d.
Participants will be admitted to the CRU on Day -1. Participants will be discharged on Day 4 of Period 5 following the final assessments.
e.
This will be applicable for Period 5 only .
f.
Medical history will include a history of prior illegal drug, alcohol, and tobacco use, as well as blood donation within prior 60 days. Medical history will be recorded at 
Screening and updated on Period 1 Day -1. 
g.
Demographics will include participant race, ethnicity, age, and gender during the Screening visit. 
h.
Physical exam will be performed by trained medical personnel at the investigator site at Screening or Period 1 Day -1 only (height and weight must be obtained at Screening 
to obtain BMI for eligibility criteria). A brief PE may be performed at other designated time points at the discretion of the investigator. 
i.
Safety laboratory assessments including urinalysis, hematology, chemistry and coagulation will be performed at Screening, Period 1 Day -1, Period 5 Day 4, and early 
termination/discontinuation if applicable. All the safety laboratory samples must be collected following at least a 4-hour fast. Additional safety laboratory assessments may be 
performed at any time at the discretion of the investigator.
j.
For postmenopausal (amenorrheic for at least 12 consecutive months) female participants only.
k.
Urine drug (mandatory) and alcohol breath test (at discretion of investigator) will be performed at Screening and on Period 1 Day -1. These tests may be performed at any 
other time at the discretion of the investigator.
l.
HBsAb will be tested if HBsAg and/or HBcAb are positive. 
m.
The investigator or his/her designee will discuss with the participant the need to use highly effective contraception consistently and correctly according to contraception 
guidelines.
n.
Single 12-lead ECG readings approximately will be taken at specified time point. All ECG assessments will be made after at least a 5-minute rest in a supine position and 
prior to any blood draws or vital sign measurements.
PPD
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Visit Identifier
Abbreviations used in this table may be 
found in Appendix 8
Screeninga
Periods 1-5
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1b
Day 1
Day 
2
Day 3 Day 4 28-35 Daysc
Hours After Dose
0
0.5
1
1.5
2
2.5
3
4
6
8
12
16
24
48
72
o.
This will be done pre-dose of Day 1 of treatment period 1 and also on Day 4 of treatment period 5.
p.
Single supine BP PR will be performed following at least a 5-minute rest in a supine position, at specified time point. BP and PR assessments will be performed after 
collection of ECGs and prior to collection of blood draws if scheduled at the same time.
q.
Check exposure to positive participant, residence or travel in area of high incidence and COVID-19 related signs and symptoms. 
r.
The testing for COVID-19 pathogen by RT-PCR will be performed at specified time point and an additional SARS-CoV-2 test will also be performed after 4 days (ie, upon 
completion of 4 × 24 hours in house), ie, Period 1 Day 4. Additional testing for COVID-19 pathogen will also be done as per local requirements or by the principle 
investigator.
s.
Temperature measurementsmay be done more frequently as clinically warranted.
t.
PF-07321332 will be administered orally after overnight fasting on Day 1 of each treatment period. There will be at least a 4-day washout between each dose.
u.
Ritonavir 100 mg will be administered approximately at -12, 0, and 12 hours relative to the dose of PF-07321332 on Day 1 for treatment A, B, C and D only.
v.
One (approximately 4 mL) blood sample for PK analysis of PF-07321332 will be taken at the designated time points post dose in each dosing period.
w.
Prep D1 Retained Research Samples for Genetics and Prep B2: 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. These samples will be collected in Period 1 only.
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2. INTRODUCTION
PF-07321332 is a potent and selective inhibitor of the SARS-CoV-2 3CL protease that is 
currently being developed as an oral treatment of COVID-19. Ritonavir is a strong CYP3A4 
inhibitor being used to inhibit the metabolism of PF-07321332 in order to increase plasma 
concentrations of PF-07321332 to values that are anticipated to be efficacious. 
2.1. Study Rationale 
The purpose of this study is to estimate the rBA of PF-07321332 slower dissolution and 
larger particle size tablet formulations and SDD extemporaneous suspension formulation 
relative to the commercial tablet formulation in healthy adult participants under fasted 
condition.
This study objective is to estimate the rBA of single doses of PF-07321332 300 mg slower 
dissolution tablet formulation and larger particle size tablet formulation with ritonavir 
100 mg compared to a 300 mg doses of PF-07321332 commercial tablet formulation with 
ritonavir 100 mg. An additional objective of this study is to estimate the rBA of PF-
07321332 300 mg doses SDD extemporaneous suspension formulation administered with
and without ritonavir 100 mg compared to PF-07321332 300 mg doses commercial tablet 
formulation coadministered with ritonavir 100 mg. 
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 30 January 2020 and further characterized the 
disease outbreak as a pandemic on 11 March 20201.
PF-07321332 is an orally bioavailable 3CLpro inhibitor shown to be effective against 
SARS-CoV-2 3CLpro (Ki = 0.00311 μM) in a biochemical enzymatic assay. PF-07321332 is 
being developed as an oral treatment in patients with COVID-19 infection.
Ritonavir is a strong CYP3A4 inhibitor being used to inhibit the metabolism of PF-07321332 
in order to increase plasma concentrations of PF-07321332 to values that are anticipated to 
be efficacious. Ritonavir is not expected to have any pharmacological impact on the 
SARS-CoV-2 virus and its elimination. Ritonavir is being used only as a PK boosting agent.
 
 
 
2.2.1. Nonclinical Pharmacology
Details of the nonclinical pharmacology of PF-07321332 can be found in the current IB2.
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2.2.2. Nonclinical Pharmacokinetics and Metabolism
Hepatic CYP3A enzymes were identified as the main pathway for clearance of PF-07321332 
in vitro in liver microsomes (mouse, rat, hamster, rabbit, monkey, and human), hepatocytes 
(rat, monkey, and human), and in vivo in rat and monkey after repeat oral dosing. In a 
reaction phenotyping study using human liver microsomes in the presence of selective CYP 
inhibitors, CYP3A4 was predicted to be the major contributor (fm = 0.99) to the in vitro 
oxidative metabolism of PF-07321332. No significant CYP3A5 contribution is expected to 
the metabolism of PF-07321332. 
Additional information of the nonclinical PK and metabolism of PF-07321332 is available in 
the current IB2.
2.2.3. Nonclinical Safety
There were no adverse findings observed in repeat-dose toxicity studies in rats and monkeys 
up to 2 weeks duration and the NOAELs were the highest dose administered (1000 mg/kg 
and 600 mg/kg in the rat and monkey studies, respectively). PF-07321332-related
non-adverse, test article-related clinical findings included sporadic occurrence of emesis with 
slight body weight decreases in monkeys in the 1-month study. In rats, monitorable and 
reversible clinical pathology findings included those possibly suggestive of low-grade 
inflammation or alterations in the coagulation pathways without clinical or microscopic 
correlates. In monkeys, monitorable and reversible clinical pathology findings included an 
increase in ALT and/or AST and an increase in fibrinogen at the high dose in the 1-month 
study without clinical or microscopic correlates. In rats administered 1000 mg/kg/day, lower 
mean absolute and relative heart weights (females) and higher mean liver weights (both 
sexes) were observed relative to controls. The lower heart weights had no microscopic 
correlates and were fully reversed at the end of the 2-week recovery period. Higher liver 
weights correlated with reversible, non-adverse microscopic findings of minimal to mild 
severity in the liver and thyroid gland consistent with adaptive changes related to microsomal 
enzyme induction.
PF-07321332 was not mutagenic or clastogenic in in vitro genetic toxicity studies and was 
negative in the in vivo rat micronucleus assay incorporated into the GLP repeat-dose rat 
toxicity study. 
The nonclinical studies performed adequately support the oral administration of 
PF-07321332 in the clinic for up to 14 days. 
Further details of the nonclinical safety program are provided in the current IB2.
 
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2.2.4.1. Safety Overview
PF-07321332 was generally safe and well-tolerated in healthy participants at single doses of 
PF-07321332 ranging from 150 mg to 1500 mg alone and at 250 mg and 750 mg with 
ritonavir (100 mg at -12h, 0h, 12h) in the PART-1: SAD, ten days of dosing from 75 mg 
q12h to 500 mg q12h with 100 mg ritonavir q12h in the PART-2: MAD, single doses of 
PF-07321332 250 mg as 250 mg tablet (under fasted or fed state) and oral suspension (under 
fasted state) in the PART-3: relative bioavailability/food effect, single dose of PF-07321332 
300 mg (oral suspension) with ritonavir 100 mg (dosed at -12h, 0h, 12h and 24h) in the 
PART-4: metabolism and excretion study, and split dosing administration (3 doses of 
750 mg) of PF-07321332 at short intervals (approximately 2 hours of the previous dose) with 
ritonavir 100 mg (dosed at -12h, 0h, and 12h) in the PART-5: supratherapeutic exposure 
cohort of the study. 
Following single doses of PF-07321332 with and without ritonavir, all AEs were mild and 
none were considered treatment related. There were no obvious trends in, or association of, 
TEAEs with dose level of PF-07321332. Following multiple doses, the most commonly 
observed AEs by system organ class were gastrointestinal disorders. Diarrhea was the most 
common reported AE, occurring in 5 participants across treatment groups. A total of 
8 treatment related TEAEs were observed in Part-2: MAD. Across treatment groups, blood 
TSH increased in 5 participants, and 3 participants reported dysgeusia. The 5 participants 
with elevated TSH results did not experience related clinical symptoms. In PART-3, the most 
commonly observed TEAEs by system organ class were general disorders and administration 
site conditions occurring in 5 participants across treatment groups. Vessel puncture site 
hematoma was the most common reported TEAE, occurring in 3 participants across 
treatment groups. A total of 4 treatment related TEAEs were observed in PART-3. In 
PART-4, one TEAE (nasopharyngitis) was reported by 1 participant. In PART-5, the most 
commonly observed TEAEs by system organ class were gastrointestinal disorders. 
Abdominal pain was the most common reported TEAE, occurring in 2 participants across 
treatment groups. Nausea (1 participant) and vomiting (1 participant) were considered 
treatment-related AEs. All reported AEs have been of mild intensity except for 
nasopharyngitis which was reported by 1 participant in PART-4. This AE was moderate in 
severity and not considered treatment-related. There were no deaths, SAEs or dose reductions 
due to AEs reported in this study. One participant in PART-1 discontinued from the study 
due to AE (asymptomatic COVID-19). There were no clinically meaningful findings in vital 
signs, ECG, or potential Hy’s Law cases reported during this study. 
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Further details on the clinical safety information with PF-07321332 are provided in the 
current IB2.
2.2.4.2. Summary of PF-07321332 Pharmacokinetics in Human
Single dose PK data from Study C4671001 at PF-07321332 doses of 150 mg, 500 mg, and 
1500 mg alone and at 250 mg and 750 mg with ritonavir 100 mg (dosed at -12, 0, and 
12 hours) show that PF-07321332 was absorbed rapidly with median Tmax of 1 hour or less 
when administered alone and 2.75 hours or less when administered with ritonavir. Since 
PF-07321332 is primarily metabolized by CYP3A4 and ritonavir is a CYP3A4 inhibitor, 
dosing with ritonavir increased the exposure of PF-07321332. Highest observed mean Cmax
and AUClast was 5.09 µg/mL and 64.26 µg.h/mL, respectively, at 750 mg PF-07321332 
dosed with ritonavir. The mean half-life of PF-07321332 was approximately 2 hours when 
administered alone and increased to approximately 6-13 hours when co-administered with 
ritonavir. Dosing with a high-fat meal modestly increased the exposure of PF-07321332 
(approximately 15% increase in mean Cmax and 1.6% increase in mean AUClast). 
PK data on Day 1, Day 5 and Day 10 following multiple oral administration of 
PF-07321332/ritonavir 75/100 mg, 250/100 mg, and 500/100 mg q12h suggests a less than 
dose proportional increase in exposure at steady state. Following multiple dosing over 
10 days steady state was achieved on Day 2 with approximately 2-fold accumulation. Day 5 
and Day 10 exposure was similar at all doses. Approximately 32.5% to 64.6% of the drug 
was excreted unchanged in urine across different doses at steady-state. The renal clearance 
ranged between 3.5 to 4.4 L/h across doses.
Metabolism and excretion data following oral administration of PF-07321332/ritonavir 
300/100 mg showed that overall mean ± SD (range) mass recovery of PF-07321332-related 
material in excreta (urine and feces) was 84.9 ± 8.9% which included 80.7 ± 8.0% by 
quantitative 19F-NMR and 4.2 ± 1.3% excreted as metabolite M8 (19F-NMR silent due to loss 
of trifluoroacetyl group) quantified by UHPLC-HRMS/MS. The excretion into urine and 
feces was 49.6% and 35.3 %, respectively. Almost all of the excretion of drug-related 
material occurred over the first five days following the dose, and most of the drug-related 
material that was excreted in the urine appeared in within the first day following the dose.
The metabolite profile of PF-07321332 in urine and feces was also evaluated using 19F-NMR 
spectroscopy. After normalization of the data to 100% mass balance, unmetabolized 
PF-07321332 represented 82.5% of the recovered dose, with 55.0% in urine and 27.5% in 
feces. Metabolite M5, which is formed via amide bond hydrolysis of PF-07321332, 
constituted 12.1% of dose, with almost all appearing in feces. All other fluorine-containing 
metabolites were minor (<1% of dose), and M8 was 4.2% of the administered dose. In 
plasma, only the unchanged PF-07321332 was observed. These findings were further 
corroborated with the quantitative HPLC-MS/MS assay for PF-07321332 and metabolite M5. 
Further details on the clinical PK of PF-07321332 are provided in the current IB2.

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2.3. Benefit/Risk Assessment
PF-07321332 is not expected to provide any clinical benefit to healthy participants in this 
study. This study is designed primarily to further the understanding of human PK, 
metabolism, and elimination of PF-07321332.
 
 
 
 
 
 
More detailed information about the known and expected benefits and risks and reasonably 
expected adverse events of PF-07321332 and ritonavir may be found in the IB2, which is the 
SRSD for this study. 
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3. OBJECTIVES AND ENDPOINTS
Primary Objective: 
Primary Endpoint: 

To estimate the rBA of the PF-07321332 slower
dissolution tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg compared to 
the PF-07321332 commercial tablet formulation
(2 × 150 mg) ritonavir 300/100 mg under fasted
conditions.

To estimate the rBA of the PF-07321332 larger 
particle size tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg compared to 
the PF-07321332 commercial tablet formulation
(2 × 150 mg)/ritonavir 300/100 mg under fasted
conditions.

To estimate the rBA of the PF-07321332 SDD 
suspension formulation/ritonavir 300/100 mg 
compared to the PF-07321332 commercial tablet 
formulation (2 × 150 mg)/ritonavir 300/100 mg
under fasted conditions.

To estimate the rBA of the PF-07321332 SDD 
suspension formulation (300 mg) without ritonavir 
compared to the PF-07321332 commercial tablet 
formulation (2 × 150 mg)/ritonavir 300/100 mg 
under fasted conditions.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.

Plasma PF-07321332 PK parameters: AUClast, 
AUCinf (if data permits) and Cmax.
Secondary Objective: 
Secondary Endpoints: 

To evaluate the safety and tolerability of 
PF-07321332/ritonavir in healthy participants.

Assessment of TEAEs, clinical laboratory 
abnormalities, vital signs, and 12-lead ECGs.
Tertiary/Exploratory Objective:
Tertiary/Exploratory Endpoints:

To characterize the PK of PF-07321332 after
single oral doses of different formulations.

Plasma PF-07321332 PK parameters: t½ (if 
data permits), CL/F, Vz/F (if data permits) and 
Tmax of PF-07321332.
4. STUDY DESIGN
4.1. Overall Design
This is a Phase 1, open-label, single-dose, randomized, crossover study in healthy adult 
participants to evaluate relative bioavailability of PF-07321332 slower dissolution tablet
formulation (Test formulation 1) and larger particle size tablet formulation (Test 
formulation 2), compared to the PF-07321332 commercial tablet formulation (Reference 
formulation) under fasted conditions. An additional objective of this study is to estimate the 
rBA of PF-07321332 300 mg doses SDD extemporaneous suspension formulation 
administered with (Test formulation 3) and without (Test formulation 4) ritonavir 100 mg 

PF-07321332 
Protocol C4671008
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PFIZER CONFIDENTIAL
Page 25
compared to PF-07321332 300 mg doses commercial tablet formulation administered with 
ritonavir 100 mg (Reference).
Approximately 12 healthy male and/or female participants will be enrolled and randomized 
to 1 of 6 possible treatment sequences to ensure at least 10 participants will complete the 
study. Participants who discontinue from the study for non-safety reasons may be replaced at 
the sponsor’s discretion in collaboration with the Invesitgator. The replacement participant 
will receive the same treatment sequences as the participant who discontinued. 
Each enrolled participant will participate in 5 study periods to receive 5 different treatments 
according to the sequence determined by randomization: 

Treatment A: PF-07321332 300 mg (2 × 150 mg commercial tablets)/100 mg 
ritonavir 

Treatment B: PF-07321332 300 mg (2 × 150 mg slower dissolution tablets)/100 mg 
ritonavir 

Treatment C: PF-07321332 300 mg (2 × 150 mg large particle size tablets)/100 mg 
ritonavir 

Treatment D: PF-07321332 300 mg (SDD suspension)/100 mg ritonavir

Treatment E: PF-07321332 300 mg (SDD suspension)
Participants will be randomly assigned to 1 of 6 sequences as shown below in Table 1.
Participants will be discharged on Day 4 of Period 5, following completion of all 
assessments. Between each treatment, a minimum of 4 days washout is proposed to minimize 
any residual PF-07321332 concentrations prior to start of the next treatment. The total 
planned duration of participation from the Screening visit to the last Follow-up phone call, is 
approximately 12 weeks.
Table 1.
Randomized Treatment Sequences
Treatment
Sequence
Period 1
Period 2
Period 3
Period 4
Period 5
Sequence 1 (N =2)
Treatment A
Treatment B
Treatment C
Treatment D
Treatment E
Sequence 2 (N =2)
Treatment B
Treatment C
Treatment A
Treatment D
Treatment E
Sequence 3 (N =2)
Treatment C
Treatment A
Treatment B
Treatment D
Treatment E
Sequence 4 (N =2)
Treatment A
Treatment C
Treatment B
Treatment E
Treatment D
Sequence 5 (N =2)
Treatment B
Treatment A
Treatment C
Treatment E
Treatment D
Sequence 6 (N =2)
Treatment C
Treatment B
Treatment A
Treatment E
Treatment D
Healthy participants will be screened to determine eligibility within 28 days prior to study 
treatment. Medical history and results of physical examinations, vital signs, 12-lead ECGs, 
and clinical laboratory evaluations will determine eligibility. Eligible participants will be 
admitted to the CRU on Day -1 and will be confined in the CRU until discharge.

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On Day 1 of each period, participants will receive a single dose of study intervention
PF-07321332 along with or without 100 mg of ritonavir as per randomization schedule.
Additional doses of ritonavir 100 mg will be administered approximately at -12, and 12 hours 
relative to the dose of PF-07321332 for treatment A, B, C and D only. Study treatments will 
be administered with approximately 240 mL of ambient temperature water under fasted
conditions (overnight fast and no food until 4 hours after dosing). Serial PK samples will be 
collected up to 72 hours post dose. Participants will be discharged from the CRU on Period 5, 
Day 4 following completion of all assessments.
If a participant has any clinically significant, study related abnormalities at the conclusion of 
a scheduled inpatient portion of the study, the Pfizer medical monitor (or designated 
representative) should be notified and the participant may be asked to remain in the CRU 
until such abnormalities are deemed not clinically significant, or it is safe for outpatient 
follow-up. A safety follow-up call will be made to participants approximately 28 to 35 days 
from administration of the final dose of study intervention.
4.2. Scientific Rationale for Study Design
The objective of the study is to estimate the relative bioavailability of PF-07321332 slower 
dissolution tablet formulation (Test formulation 1), and larger particle size tablet formulation
(Test formulation 2),compared to PF-07321332 commercial tablet formulation (Reference 
formulation). An additional objective of this study is to estimate the rBA of PF-07321332 
300 mg doses SDD extemporaneous suspension formulation administered with (Test 
formulation 3) and without (Test formulation 4) ritonavir 100 mg compared to PF-07321332
300 mg doses commercial tablet formulation administered with ritonavir 100 mg 
(Reference).
PK of the slower dissolution tablet formulation and larger particle size tablet formulation 
relative to the target formulation (commercial) will be evaluated as to investigate the effect of 
dissolution rate and API particle size on the bioavailability of PF-07321332, respectively. 
This data will enable establishing the dissolution and particle size release specifications with 
clinical safe space for commercial supplies. SDD is an exploratory formulation developed to 
gain understanding of the absorption characteristics of the molecule by eliminating the 
contributions of dissolution and solubility. Data from this study will be used to develop 
correlation between in vitro dissolution and in vivo PK and to develop and validate 
physiological based pharmacokinetic model for different dissolution rate as well as SDD as 
an alternative formulation.
The study is being designed as a crossover study to account for any period effect. Between 
each treatment, a minimum of 4 days washout is proposed to minimize any residual 
PF-07321332 concentrations prior to start of the next treatment, as PF-07321332 has half-life 
of approximately 6 to13 hours when co-administered with ritonavir.

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4.2.1. Choice of Contraception/Barrier Requirements 
Human reproductive safety data are limited for PF-07321332, but there is no suspicion of 
human teratogenicity based on the intended pharmacology of the compound. Therefore, the 
use of a highly effective method of contraception is required (see Appendix 4).
4.2.2. 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 dose of PF-07321332 300 mg/ritonavir 100 mg BID for 5 days is the approved 
therapeutic dose and treatment duration under emergency use authorization. 
 
 
This study is designed to evaluate rBA of various PF-07321332 formulations in healthy adult 
participants at approved therapeutic dose. Therefore single oral dose PF-07321332
300 mg/ritonavir 100 mg will be used in this relative bioavailability study. 
Physiological based pharmacokinetic modeling and simulations predicted higher exposure 
(Cmax and AUC) of PF-07321332 for SDD formulation compared to commercial tablet 
formulation. Safety of higher exposure of PF-07321332 with SDD formulation is supported 
by PK and safety data from the supratherapeutic exposure cohort in the
study. In 
the supratherapeutic exposure cohort, PF-07321332 2250 mg dose was administered as 3 
split doses of 750 mg of PF-07321332 at short intervals (approximately 2 hours from the 
previous dose) with ritonavir 100 mg (dosed at -12h, 0h, and 12h). The Cmax and AUCinf of 
PF-07321332 at the supratherapeutic dose of 2250 mg were 15.940 μg/mL and 
188.800 μg•hr/mL, respectively, which were 7 to 8 fold higher than the Cmax and AUCinf of 
PF-07321332 observed at the 300 mg dose of commercial tablet formulation. Therefore, to 
evaluate the rBA of SDD formulation against the commercial tablet fommulation, 
PF-07321332 300 mg (SDD suspension)/100 mg ritonavir and PF-07321332 300 mg (SDD 
suspension) alone will be used in this study.
4.4. End of Study Definition
The end of the study is defined as the date of last scheduled procedure shown in the SoA for 
the last participant in the trial.
A participant is considered to have completed the study if he/she has completed all parts of 
the study, including the last scheduled procedure shown in the SoA.
5. STUDY POPULATION
This study can fulfill its objectives only if appropriate participants are enrolled. 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 
CCI
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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 ≥18 years of age, inclusive, at the time of signing the ICD.

Refer to Appendix 4 for reproductive criteria for male (Section 10.4.1) and female
(Section 10.4.2) participants.
Type of Participant and Disease Characteristics:
2. Male and female participants who are overtly healthy as determined by medical 
evaluation including medical history, PE, laboratory tests, vital signs and standard 
12-lead ECGs.
3. Participants who are willing and able to comply with all scheduled visits, treatment 
plan, laboratory tests, lifestyle considerations, and other study procedures.
4. Female participants of childbearing potential must have a negative pregnancy test.
Weight: 
5. BMI of 17.5 to 30.5 kg/m2; and a total body weight >50 kg (110 lb).
Informed Consent: .
6. Capable of giving signed informed consent as described in Appendix 1, which 
includes compliance with the requirements and restrictions listed in the ICD and in 
this protocol.
5.2. Exclusion Criteria
Participants are excluded from the study if any of the following criteria apply:
Medical Conditions:
1. Positive test result for SARS-CoV-2 infection at the time of Screening or Day -1.
2. Evidence or history of clinically significant hematological, renal, endocrine, 
pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or 

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allergic disease (including drug allergies, but excluding untreated, asymptomatic, 
seasonal allergies at the time of dosing).
3. Clinically relevant abnormalities requiring treatment (eg, acute myocardial infarction, 
unstable ischemic conditions, evidence of ventricular dysfunction, serious tachy- or 
brady-arrhythmias) or indicating serious underlying heart disease (eg, prolonged PR 
interval, cardiomyopathy, heart failure greater than NYHA 1, underlying structural 
heart disease, Wolff Parkinson-White syndrome). 
4. Any condition possibly affecting drug absorption (eg, gastrectomy, cholecystectomy). 
5. History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, 
HBcAb or HCVAb. Hepatitis B vaccination is allowed.
6. Other medical or psychiatric condition including recent (within the past year) or 
active suicidal ideation/behavior or laboratory abnormality or other conditions or 
situations related to COVID-19 pandemic (eg, contact with positive case, residence, 
or travel to an area with high incidence) that may increase the risk of study 
participation or, in the investigator’s judgment, make the participant inappropriate for 
the study.
Prior/Concomitant Therapy:
7. Use of prescription or nonprescription drugs and dietary and herbal supplements 
within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study 
intervention. Refer to Section 6.8 Concomitant Therapy for additional details.

Concomitant use of any medications or substances that are strong inducers of
CYP3A4 are prohibited within 28 days prior to first dose of 
PF-07321332/ritonavir and during study treatment.

Concomitant use of any medications or substances that are inhibitors of CYP3A4 
are prohibited during study treatment and 4 days after the last dose of study 
intervention.
8. Current use of any prohibited concomitant medication(s) or those unwilling/unable to 
use a permitted concomitant medication(s). Refer to Section 6.8 Concomitant 
Therapy.
9. Participant who have received a COVID-19 vaccine within 7 days before screening or 
admission, or who are to be vaccinated with a COVID-19 vaccine at any time during 
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Prior/Concurrent Clinical Study Experience:
10. Previous administration with an investigational drug 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). Participants who have participated in 
previous clinical trials with PF-07321332 may be eligible to participate in this study 
as long as they meet all other criteria. 
Diagnostic Assessments:
11. A positive urine drug test.
12. Screening supine BP ≥140 mm Hg (systolic) or ≥90 mm Hg (diastolic), following at 
least 5 minutes of supine rest. If BP is ≥140 mm Hg (systolic) or ≥90 mm Hg
(diastolic), the BP should be repeated 2 more times and the average of the 3 BP 
values should be used to determine the participant’s eligibility.
13. Baseline 12-lead ECG (single) that demonstrates clinically relevant abnormalities that
may affect participant safety or interpretation of study results (eg, baseline QTcF 
interval >450 msec, complete LBBB, signs of an acute or indeterminate-age 
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 msec, this interval should be 
rate-corrected using the Fridericia method and the resulting QTcF should be used for 
decision making and reporting. If QTcF exceeds 450 msec, or QRS exceeds 
120 msec, the ECG should be repeated 2 more times and the average of the 3 QTcF or 
QRS values should be used to determine the participant’s eligibility.
Computer-interpreted ECGs should be overread by a physician experienced in 
reading ECGs before excluding a participant.
14. Participants with ANY of the following abnormalities in clinical laboratory tests at 
Screening, as assessed by the study-specific laboratory and confirmed by a single 
repeat test, if deemed necessary: 

AST or ALT level >1.5 × ULN;

Total bilirubin level ≥1.5 × ULN; participants with a history of Gilbert's 
syndrome may have direct bilirubin measured and would be eligible for this study 
provided the direct bilirubin level is ≤ULN.

eGFR <60 mL/min/1.73 m2 based on the CKD-EPI equation.
Other Exclusions:
15. History of alcohol abuse or binge drinking and/or any other illicit drug use or 
dependence within 6 months of Screening. Binge drinking is defined as a pattern of 

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5 (male) and 4 (female) or more alcoholic drinks in about 2 hours. As a general rule, 
alcohol intake should not exceed 14 units per week (1 unit = 8 ounces (240 mL) beer, 
1 ounce (30 mL) of 40% spirit or 3 ounces (90 mL) of wine).
16. Use of tobacco or nicotine containing products in excess of the equivalents of 
5 cigarettes per day or 2 chews of tobacco per day.
17. Blood donation (excluding plasma donations) of approximately 1 pint (500 mL) or 
more within 60 days prior to dosing. 
18. History of sensitivity to heparin or heparin-induced thrombocytopenia. 
19. Unwilling or unable to comply with the criteria in the Lifestyle Considerations
section of this protocol.
20. Investigator site staff or Pfizer employees directly involved in the conduct of the 
study, site staff otherwise supervised by the investigator, and their respective family 
members. 
21. History of sensitivity reactions to ritonavir, or any of the formulation components of 
PF-07321332, or ritonavir.
22. Pregnant or breastfeeding women.
5.3. Lifestyle Considerations
5.3.1. Meals and Dietary Restrictions

Participants must abstain from all food and drink (except water) at least 4 hours prior 
to any safety laboratory evaluations and 10 hours prior to the collection of the predose 
PK sample on Day 1 of each Period.

Water is permitted until 1 hour prior to study intervention administration. Water may 
be consumed without restriction beginning 1 hour after PF-07321332 dosing.
Noncaffeinated drinks (except red wine, grapefruit or grapefruit-related citrus fruit 
juices—see below) may be consumed with meals and the evening snack.

Lunch will be provided approximately 4 hours after morning dosing.

Dinner will be provided approximately 9 to 10 hours after morning dosing.

An evening snack may be permitted.

Participants will refrain from consuming red wine, grapefruit, or grapefruit-related 
citrus fruits (eg, Seville oranges, pomelos, fruit juices) from 7 days prior to the first 
dose of study intervention until collection of the final PK blood sample.

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
While participants are confined, their total daily nutritional composition should be 
approximately 55% carbohydrate, 30% fat, and 15% protein. The daily caloric intake 
per participant should not exceed approximately 3200 kcal.
5.3.2. Caffeine, Alcohol, and Tobacco

Participants will abstain from caffeine-containing products for 24 hours prior to the 
start of dosing until collection of the final PK sample of each study period.

Participants will abstain from alcohol for 24 hours prior to admission (except as 
stated above for red wine) to the CRU and continue abstaining from alcohol until 
collection of the final PK sample of each study period. Participants may undergo an 
alcohol breath test or blood alcohol test at the discretion of the investigator.

Participants will abstain from the use of tobacco- or nicotine-containing products for 
24 hours prior to dosing and during confinement in the CRU.
5.3.3. Activity

Participants will abstain from strenuous exercise (eg, heavy lifting, weight training, 
calisthenics, aerobics) for at least 48 hours prior to each blood collection for clinical 
laboratory tests. Walking at a normal pace will be permitted;

In order to standardize the conditions on PK sampling days, participants will be 
required to refrain from lying down (except when required for BP, pulse rate, and 
ECG measurements), eating, and drinking beverages other than water during the first 
4 hours after PF-07321332/ritonavir dosing;

Participants will be confined to the procedure room for the first 4 hours after dosing 
on Day 1, except to use the bathroom. After this, participants may be ambulatory but 
should not engage in strenuous activities.
5.3.4. Contraception
The investigator or his or her designee, in consultation with the participant, will confirm that 
the participant has selected 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 correct use. At time points indicated in the schedule of activities (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 or if pregnancy is known or suspected in the participant or partner.

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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. Screen failure data are collected and remain as 
source and are not reported on the CRF.
Individuals who do not meet the criteria for participation in this study (screen failure) may be 
rescreened.
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY
Study intervention is defined as any investigational intervention(s), marketed product(s), 
placebo, medical device(s), or study procedure(s) intended to be administered to a study 
participant according to the study protocol.
For the purposes of this protocol, study intervention refers to PF-07321332 and ritonavir.
6.1. Study Intervention(s) Administered
For this study, the study interventions are the PF-07321332 slower dissolution tablet
formulation (Test formulation 1), larger particle size tablet formulation (Test 
formulation 2),SDD extemporaneous suspension formulation (Test formulation 3 and Test 
formulation 4), and a commercial tablet formulation of PF-07321332 (Reference 
formulation), and will be supplied by Pfizer.
Commercially available 100 mg ritonavir tablets will be supplied by the PCRU.
6.1.1. Administration
Study interventions will be administered orally and according to the conditions described in 
the SoA section and Protocol Section 5.3.1 Meals and Dietary Restrictions.
On Day 1 of each treatment period, following an overnight fast of at least 10 hours,
participants will receive PF-07321332 300 mg as 2 × 150 mg slower dissolution or larger 
particle size or commercial tablets or PF-07321332 300 mg as SDD suspension, administered 
orally with or without ritonavir 100 mg (as 1 × 100 mg tablet) administered orally starting at 
approximately 0800 hours (plus or minus 2 hours). Participants will receive additional 
2 doses of ritonavir 100 mg as a PK boosting agent as per SoA. PF-07321332 and ritonavir 
will be dosed simultaneously (within no more than 5 minutes of each other). Investigator site 
personnel will administer study intervention with ambient temperature water to a total 
volume of approximately 240 mL. Participants will swallow all tablet formulations whole 
and will not manipulate or chew the tablets prior to swallowing. 
In order to standardize the conditions on PK sampling days, all participants will be required 
to refrain from lying down (except when required for BP, pulse rate, and ECG 
measurements), eating, and drinking beverages other than water during the first 4 hours after 
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6.2. Preparation, Handling, Storage, and Accountability
1. The investigator or designee must confirm appropriate temperature conditions 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 or administer study intervention. 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 for 
all site storage locations upon return to business.
3. Any excursions from the study intervention label storage conditions should be 
reported to Pfizer upon discovery along with any actions taken. The site should 
actively pursue options for returning the study intervention to the storage conditions 
described in the labeling, as soon as possible. Once an excursion is identified, the 
study intervention must be quarantined and not used until Pfizer provides permission 
to use the study intervention. Specific details regarding the definition of an excursion 
and information the site should report for each excursion will be provided to the site 
in the PCRU site procedures.
4. Any storage conditions stated in the SRSD will be superseded by the storage 
conditions stated on the label.
5. Study interventions should be stored in their original containers.
6. The investigator, institution, or the head of the medical institution (where applicable) 
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.
7. Further guidance and information for the final disposition of unused study 
interventions are provided in the PCRU’s site procedures. 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.

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6.2.1. Preparation and Dispensing
Within this protocol, preparation refers to the investigator site activities performed to make 
the study intervention ready for administration or dispensing to the participant by qualified 
staff. Dispensing is defined as the provision of study intervention, concomitant treatments, 
and accompanying information by qualified staff member(s) to a healthcare provider, 
participant in accordance with this protocol. Local health authority regulations or investigator 
site guidelines may use alternative terms for these activities.
PF-07321332 300 mg (2 × 150 mg) tablets will be prepared at the CRU in the individual 
dosing containers by 2 operators, 1 of whom is an appropriately qualified and experienced 
member of the study staff (eg, physician, nurse, physician’s assistant, nurse practitioner, 
pharmacy assistant/technician, or pharmacist). The tablets will be provided in unit dose 
containers and labeled in accordance with Pfizer regulations and the clinical site’s labeling 
requirements. 
Commercial ritonavir (Norvir® or other local commercialized product) oral tablets will be 
dispensed at the CRU into individual dosing containers using the package insert as guidance. 
All study intervention should be prepared and dispensed by an appropriately qualified and 
experienced member of the study staff (eg, physician, nurse, physician’s assistant, nurse 
practitioner, pharmacy assistant/technician, or pharmacist) as allowed by local, state, and 
institutional guidance. A second staff member will verify the dispensing.
PF-07321332 oral dosing suspensions will be prepared extemporaneously at the CRU by 2 
operators, 1 of whom is an appropriately qualified and experienced member of the study staff 
(eg, physician, nurse, physician’s assistant, nurse practitioner, pharmacy assistant/technician, 
or pharmacist). Details of dose preparations will be given in the EDR. Prepared doses will be 
provided in unit dose containers and labeled in accordance with Pfizer regulations and the 
investigator site’s labeling requirements.
6.3. Measures to Minimize Bias: Randomization and Blinding
6.3.1. Allocation to Study Intervention
The investigator’s knowledge of the treatment should not influence the decision to enroll a 
particular participant or affect the order in which participants are enrolled.
The investigator will assign participant numbers to the participants as they are screened for 
the study. Pfizer will provide a randomization schedule to the investigator and, in accordance
with the randomization numbers, the participant will receive the study treatment regimen 
assigned to the corresponding randomization number.
6.4. Study Intervention Compliance
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 CRU will be recorded in the source documents and recorded in the CRF.
The dose of study intervention and study participant identification will be confirmed at the 

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time of dosing by a member of the study site staff other than the person administering the 
study intervention. Study site personnel will examine each participant’s mouth to ensure that 
the study intervention was ingested.
6.5. Dose Modification
No dose modification is anticipated.
6.6. Continued Access to Study Intervention After the End of the Study
No intervention will be provided to study participants at the end of their study participation.
6.7. Treatment of Overdose
For this study, any dose of PF-07321332 greater than 300 mg or ritonavir 300 mg within a 
24-hour time period [±2 hours] 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 medical monitor within 24 hours.
2. Closely monitor the participant for any AEs/SAEs and laboratory abnormalities for at 
least 5 half-lives or 28 calendar days after the overdose of PF-07321332/ritonavir 
(whichever is longer).
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 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 medical monitor based on the clinical evaluation of the participant.
6.8. Concomitant Therapy
Participants will abstain from all concomitant treatments, except for the treatment of adverse
events and hormonal contraceptives that meet the requirements of this study in participants 
who are WOCBP (see Appendix 4).
Use of prescription or nonprescription drugs and dietary and herbal supplements are 
prohibited within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study 
intervention. Limited use of nonprescription medications that are not believed to affect 
participant safety or the overall results of the study may be permitted on a case-by-case basis 

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following approval by the sponsor. Acetaminophen/paracetamol may be used at doses of 
≤1 g/day.
As PF-07321332 and ritonavir are both primarily metabolized by CYP3A4, concomitant use 
of any medications or substances that are strong inducers of CYP3A4 are prohibited within 
28 days prior to dosing of study intervention. Additionally, ritonavir and PF-07321332 are 
inhibitors of CYP3A4. Therefore, medications highly dependent on CYP3A4 for clearance 
and for which elevated plasma concentrations may be associated with serious and/or life-
threatening events are not permitted during dosing of PF-07321332/ritonavir, through 4 days 
after the last dose of PF-07321332/ritonavir.
All concomitant treatments taken during the study must be recorded with indication, daily 
dose, and start and stop dates of administration. All participants will be questioned about 
concomitant treatment at each site visit.
Treatments taken within 28 days before the first dose of study intervention will be 
documented as a prior treatment. Treatments taken after the first dose of study intervention 
will be documented as concomitant treatments.
6.8.1. Rescue Medicine
There is no rescue therapy to reverse the AEs observed with PF-07321332 or ritonavir; 
standard medical supportive care must be provided to manage the AEs. 
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 requiring discontinuation in investigator’s view;

Pregnancy;

Positive COVID-19 test.
If study intervention is permanently discontinued, the participant will not remain in the study 
for further evaluation. See the SoA for data to be collected at the time of discontinuation of 
study intervention.
7.1.1. ECG Changes
A participant who meets either bulleted criterion based on the average of triplicate ECG 
readings will be withdrawn from the study intervention. 

QTcF >500 msec.

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
Change from baseline: QTcF >60 msec.
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.
7.1.2. Potential Cases of Acute Kidney Injury
Abnormal values in SCr concurrent with presence or absence of increase in BUN that meet 
the criteria below, in the absence of other causes of kidney injury, are considered potential 
cases of acute kidney injury and should be considered important medical events. 
An increase of ≥0.3 mg/dL (or ≥26.5 µmol/L) in SCr level relative to the participant’s own 
baseline measurement should trigger another assessment of SCr as soon as practically 
feasible, preferably within 48 hours from awareness.
If the second assessment (after the first observations of ≥0.3 mg/dL [or ≥26.5 µmol/L] in SCr
relative to the participant’s own baseline measurement) is ≥0.4 mg/dL (or ≥35.4 µmol/L), the 
participant should be discontinued from the study and adequate, immediate, supportive 
measures taken to correct apparent acute kidney injury.
Participants should return to the investigator site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the second assessment confirming abnormal 
SCr result. This evaluation should include laboratory tests, detailed history, and physical 
assessment. In addition to repeating SCr, laboratory tests should include serum BUN, serum 
creatine kinase, and serum electrolytes (including at a minimum potassium, sodium, 
phosphate/phosphorus, and calcium), in addition to urinary dipstick, urine microscopic 
examination, and urinary indices. All cases confirmed on repeat testing as meeting the 
laboratory criteria for acute kidney injury, with no other cause(s) of laboratory abnormalities 
identified, should be considered potential cases of drug-induced kidney injury irrespective of 
availability of all the results of the investigations performed to determine etiology of the 
abnormal SCr. If ≥2 healthy participants are noted to have 2 consecutive SCr results of 
≥0.3 mg/dL (or ≥26.5 µmol/L), an assessment of whether the finding may be considered an 
adverse drug reaction should be undertaken.
7.1.3. Stopping Rules
Dosing will be halted at any time if 1 of the following circumstances occurs and it is 
determined by the investigator that the occurrence is at least possibly related to the 
administration of study drug: 

A SAE (eg, a serious AE considered at least possibly related to study drug 
administration) in 1 participant.

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
Severe NSAE (eg, severe NSAEs considered at least possibly related to study drug 
administration) in 2 participants, independent of within or not within the same SOC.
When stopping rules are met, a data review will be conducted by the sponsor and 
investigator. If integrated analysis of available data leads to the conclusion that further dosing 
is justified, an amendment to the protocol may be required if additional safety monitoring is 
warranted.
7.2. Participant Discontinuation/Withdrawal From the Study
A participant may withdraw from the study at any time at his/her 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.
The participant will be permanently discontinued from the study intervention and the study at 
that time.
If a participant withdraws from the study, he/she 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.
If the participant withdraws from the study and also withdraws consent (see Section 7.2.1) 
for disclosure of future information, no further evaluations should be performed and no 
additional data should be collected. The sponsor may retain and continue to use any data 
collected before such withdrawal of consent.

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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 him or her 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 he or she 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 attend 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, he/she will be considered to have 
withdrawn from the study. 
8. STUDY ASSESSMENTS AND PROCEDURES
The investigator (or an appropriate delegate at the investigator site) must obtain a signed and 
dated ICD before performing any study-specific procedures.
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.

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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.
Participants will be screened within 28 days prior to administration of the study intervention
to confirm that they meet the study population criteria for the study. If the time between 
screening and dosing exceeds 28 days as a result of unexpected delays (eg, delayed drug 
shipment), then participants do not require rescreening if the laboratory results obtained prior 
to first dose administration meet eligibility criteria.
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 may 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 he or she has 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.
If an IV catheter is utilized for blood sample collections, ECGs and vital sign assessments 
(PR and BP) should be collected prior to the insertion of the catheter.
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
350 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.
To prepare for study participation, participants will be instructed on the information in 
Protocol Section 5.3 Lifestyle Considerations and Section 6.8 Concomitant Therapy.
8.1. Efficacy Assessments
Not applicable.

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8.2. Safety Assessments
Planned time points for all safety assessments are provided in the SoA. Unscheduled clinical 
laboratory measurements may be obtained at any time during the study to assess any 
perceived safety issues.
8.2.1. Physical Examinations
A complete PE will include, at a minimum, head, ears, eyes, nose, mouth, skin, heart and 
lung examinations, lymph nodes, and gastrointestinal, musculoskeletal, and neurological 
systems. 
A brief physical examination will include, at a minimum, assessments of general appearance, 
the respiratory and cardiovascular systems, and participant-reported symptoms.
Physical examinations may be conducted by a physician, trained physician's assistant, or 
nurse practitioner as acceptable according to local regulation. 
Height and weight will also be measured and recorded as per the SoA. For measuring weight, 
a scale with appropriate range and resolution is used and must be placed on a stable, flat 
surface. Participants must remove shoes, bulky layers of clothing, and jackets so that only 
light clothing remains. They must also remove the contents of their pockets and remain still 
during measurement of weight. 
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 8.3.1 to 8.3.3.
8.2.2. Vital Signs
Supine BP, PR will be measured with the participant’s arm supported at the level of the heart
and recorded to the nearest mm Hg after approximately 5 minutes of rest. The same arm 
(preferably the dominant arm) will be used throughout the study. Participants should be 
instructed not to speak during measurements.
The same properly sized and calibrated BP cuff will be used to measure BP each time. The 
use of an automated device for measuring BP and pulse rate is acceptable; however, when 
done manually, pulse rate will be measured in the brachial/radial artery for at least 
30 seconds. When the timing of these measurements coincides with a blood collection, BP 
and pulse rate should be obtained prior to the nominal time of the blood collection.
Additional collection times, or changes to collection times, of BP and pulse rate will be 
permitted, as necessary, to ensure appropriate collection of safety data.

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8.2.2.1. Respiratory Rate
Respiratory rate will be measured after approximately 5 minutes of rest in a supine position 
by observing and counting the respirations of the participant for 30 seconds and multiplying
by 2. When BP is to be taken at the same time, respiration measurement will be done during 
the 5 minutes of rest and before BP measurement.
8.2.2.2. Temperature
Temperature will be measured orally. No eating, drinking, or smoking is allowed for 
15 minutes prior to the measurement.
8.2.3. 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 heart rate and measures PR, QT, and QTc intervals and QRS 
complex. 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. All scheduled ECGs should be performed after the participant
has rested quietly for at least 5 minutes in a supine position. 
To ensure safety of the participants, a qualified individual at the investigator site will make 
comparisons to baseline measurements. Additional ECG monitoring will occur if a) a post
dose QTcF interval is increased by ≥60 msec from the baseline and is >450 msec; or b) an 
absolute QT value is ≥500 msec for any scheduled ECG. If either of these conditions occurs, 
then 2 additional ECGs will be collected approximately 2 to 4 minutes apart to confirm the 
original measurement. If the QTc values from these repeated ECGs remain above the 
threshold value, then a single ECG must be repeated at least hourly until QTc values from 
2 successive ECGs fall below the threshold value that triggered the repeat measurement.
If a) a post dose QTcF interval remains ≥60 msec from the baseline and is >450 msec; or b) 
an absolute QT value is ≥500 msec for any scheduled ECG for greater than 4 hours (or 
sooner, at the discretion of the investigator); or c) QTcF intervals get progressively longer, 
the participant should undergo continuous ECG monitoring. A cardiologist should be 
consulted if QTcF intervals 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 
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 7.

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8.2.4. Clinical Safety Laboratory Assessments
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.
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.
Clinically significant abnormal laboratory findings are those which 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 significantly abnormal during 
participation in the study or within 48 hours 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 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 
drug-induced liver injury.
Participants may undergo random urine drug testing at the discretion of the investigator.
Drug testing conducted prior to dosing must be negative for participants to receive study 
intervention.
8.2.5. COVID-19 Specific Assessments
Participants will be tested for SARS-COV-2 infection by RT-PCR prior to being admitted to 
the CRU for confinement and a subsequent SARS-CoV-2 test will be performed after 4 days 
(ie, upon completion of 4 × 24 hours in house), or if they develop COVID-19 like symptoms. 
Additional testing may be required by local regulations or by the Principal Investigator.
8.2.6. Pregnancy Testing 
Pregnancy tests may be urine or serum tests, but 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 the 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.

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8.3. 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). 
During the active collection period as described in Section 8.3.1, 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.
8.3.1. 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 the participant’s participation in the study (ie, 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 and after the active collection period and 
until the AE or SAE or its sequelae resolve or stabilize at a level acceptable to the 
investigator.
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 he/she 

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considers 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.
8.3.1.1. Reporting SAEs to Pfizer Safety
All SAEs occurring in a participant during the active collection period as described in 
Section 8.3.1 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 it being available.
8.3.1.2. 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 8.3.1, 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.
Reporting of AEs and SAEs for participants who fail screening are subject to the CRF 
requirements as described in Section 5.4.
8.3.2. 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.
8.3.3. 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 given in Appendix 3.

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8.3.4. 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.
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.
8.3.5. 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 exposure during pregnancy, exposure during 
breastfeeding, and occupational exposure.
Any such exposure to the study intervention under study are reportable to Pfizer Safety 
within 24 hours of investigator awareness.
8.3.5.1. 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 exposes 
a female partner prior to or around the time of conception.

A female is found to be pregnant while being exposed or having been exposed to 
study intervention due to 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, inhalation, or skin 
contact.

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
A male family member or healthcare provider who has been exposed to the study 
intervention by ingestion, inhalation, or skin contact then exposes 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 
should include the anticipated date of delivery (see below for information related to 
termination of pregnancy). 

If EDP occurs in a participant or a 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 28 days after 
the last dose.

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;

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. 

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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 
the participant was given the Pregnant Partner Release of Information Form to provide to his 
partner.
8.3.5.2. Exposure During Breastfeeding
An exposure during breastfeeding occurs if: 

A female participant is found to be breastfeeding while receiving or after 
discontinuing study intervention.

A female is found to be breastfeeding while being exposed or having been 
exposed to study intervention (ie, environmental exposure). An example of 
environmental exposure during breastfeeding is a female family member or 
healthcare provider who reports that she is breastfeeding after having been 
exposed to the study intervention by ingestion, inhalation, or skin contact.
The investigator must report exposure during breastfeeding 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 exposure during 
breastfeeding 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 exposure during breastfeeding report is not created when a Pfizer drug specifically 
approved for use in breastfeeding women (eg, vitamins) is administered in accord with 
authorized use. However, if the infant experiences an SAE associated with such a drug, the 
SAE is reported together with the exposure during breastfeeding.
8.3.5.3. 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.
8.3.6. Cardiovascular and Death Events
Not applicable.

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8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not Qualifying as AEs 
or SAEs
Not applicable.
8.3.8. Adverse Events of Special Interest
Adverse events of special interest (AESIs) are examined as part of routine safety data review 
procedures throughout the clinical trial and as part of signal detection processes.
All AESIs must be reported as an AE or SAE following the procedures described in 
Section 8.3.1 through 8.3.4. An AESI is to be recorded as an AE or SAE on the CRF. In 
addition, an AESI that is also an SAE must be reported using the CT SAE Report Form.
8.3.8.1. Lack of Efficacy
This section is not applicable because efficacy is not expected in the study population.
8.3.9. Medical Device Deficiencies
Not applicable.
8.3.10. 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.
Exposures to the study intervention under study may occur in clinical trial settings, such as 
medication errors.
Safety Event
Recorded on the CRF
Reported on the CT SAE Report 
Form to Pfizer Safety Within 
24 Hours of Awareness
Medication errors All (regardless of whether 
associated with an AE)
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.
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.
In the event of a medication dosing error, the sponsor should be notified within 24 hours.

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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.
Medication errors should be reported to Pfizer Safety within 24 hours on a CT SAE Report 
Form only when associated with an SAE.
8.4. Pharmacokinetics 
8.4.1. Plasma for Analysis of PF-07321332 and Ritonavir
Blood samples of approximately 4 mL, to provide approximately 1.5 mL plasma, will be 
collected for measurement of plasma concentrations of PF-07321332 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. Collection of 
samples up to and including 10 hours after dose administration that are obtained within 
10% of the nominal time relative to dosing (eg, within 6 minutes of a 60-minute sample) will 
not be captured as a protocol deviation, as long as the exact time of the collection is noted on 
the source document and the CRF. Collection of samples more than 10 hours after dose
administration that are obtained ≤1 hour away from the nominal time relative to dosing will 
not be captured as a protocol deviation, as long as the exact time of the collection is noted on 
the source document and the CRF. 
Samples will be used to evaluate the PK of PF-07321332. Samples collected for analyses of 
PF-07321332 concentration may also be used to evaluate safety or efficacy aspects related to 
concerns arising during or after the study, for metabolite identification, analysis of 
endogenous biomarkers, and/or evaluation of the bioanalytical method, or for other internal 
exploratory purposes.
Genetic analyses will not be performed on these plasma samples unless consent for this was 
included in the informed consent. Participant confidentiality will be maintained.
Samples collected for measurement of plasma concentrations of PF-07321332 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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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.
8.5. Genetics
8.5.1. Specified Genetics
Genetics (specified analyses) are not evaluated in this study.
8.5.2. 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.
Retained Research Samples may be used for research related to the study intervention(s) and 
safety biomarkers. Genes and other analytes (eg, proteins, RNA, nondrug metabolites) may 
be studied using the banked 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 and 
supporting documentation.
8.6. Biomarkers
Biomarkers are not evaluated in this study.
8.6.1. Specified Gene Expression (RNA) Research 
Specified gene expression (RNA) research is not included in this study.
8.6.2. Specified Protein Research 
Specified protein research is not included in this study.
8.6.3. Specified Metabolomic Research 
Specified metabolomic research is not included in this study.
8.6.4. Retained Research Samples for Biomarkers
These Retained Research Samples will be collected in this study:

10 mL whole blood (Prep B2 optimized for serum).
Retained Research Samples will be collected as local regulations and IRB/ECs allow 
according to the SoA.

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Retained Research Samples may be used for research related to the study intervention(s) and 
safety biomarkers. 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 and 
supporting documentation. 
8.7. Immunogenicity Assessments
Immunogenicity assessments are not included in this study.
8.8. Health Economics
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study.
9. STATISTICAL CONSIDERATIONS
Detailed methodology for summary and statistical analyses of the data collected in this study 
is outlined here and further detailed in an 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 Hypotheses
There are no statistical hypotheses for this study.
9.2. Analysis Sets
For purposes of analysis, the following analysis sets are defined:
Participant Analysis 
Set
Description
Enrolled/Randomly 
assigned to study 
intervention
"Enrolled" means a participant's agreement to participate in a 
clinical study following completion of the informed consent 
process and 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. A 
participant will be considered enrolled if the informed 
consent is not withdrawn prior to participating in any study 
activity after screening.
Safety Analysis Set
All participants who take at least 1 dose of study intervention.
Participants will be analyzed according to the product they 
actually received.

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Participant Analysis 
Set
Description
PK Concentration Set
All participants who take at least 1 dose of study intervention 
and in whom at least 1 concentration value is reported.
PK Parameter Set
All participants who take at least 1 dose of study intervention 
and in whom at least 1 of the PK parameters of primary
interest are reported.
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.
This section is a summary of the planned statistical analyses of the primary and secondary 
endpoints.
9.3.1. Pharmacokinetic Analyses
9.3.1.1. Derivation of Pharmacokinetic Parameters
Plasma PK parameters of PF-07321332 will be derived (as data permits) from the 
concentration-time data using standard noncompartmental methods as outlined in Table 2.
Actual PK sampling times will be used in the derivation of PK parameters. In the case that 
actual PK sampling times are not available, nominal PK sampling time will be used in the 
derivation of PK parameters.
Table 2.
Plasma PF-07321332 PK Parameters Definitions
Parameter
Definition
Method of Determination
AUCinf*
Area under the concentration-time curve from 
time 0 extrapolated to infinity
AUClast + (Clast*/kel),
where Clast* is the predicted plasma 
concentration at the last quantifiable 
time point from the log-linear 
regression analysis
AUClast
Area under the plasma concentration-time profile 
from time 0 to the time of the last quantifiable 
concentration (Clast).
Linear/Log trapezoidal method.
Cmax
Maximum observed concentration
Observed directly from data
Tmax
Time for Cmax
Observed directly from data as time of 
first occurrence
t1/2*
Terminal half-life
Loge(2)/kel, where kel is the terminal 
phase rate constant calculated by a 
linear regression of the loglinear 
concentration-time curve. Only those 
data points judged to describe the 
terminal loglinear decline will be used 
in the regression.
CL/F
Apparent clearance
Dose/AUCinf
Vz/F*
Apparent volume of distribution
Dose/(AUCinf • kel)
*If data permits.

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9.3.2. Statistical Methods for PK Data
Data for treatments A,B, and C will be analyzed separately from data for treatments A,D and 
E.
Natural log transformed AUCinf (if data permits), AUClast and Cmax will be analyzed using a 
mixed effect model with sequence, period and treatment as fixed effects and participant 
within a sequence as a random effect. Estimates of the adjusted mean differences 
(Test-Reference) and corresponding 90% CIs will be obtained from the model. The adjusted 
mean differences and 90% CIs for the differences will be exponentiated to provide estimates 
of the ratio of adjusted geometric means (Test/Reference) and 90% CI for the ratios.
Treatment A will be the Reference treatment while Treatments B,and C, will be the Test 
treatments.
For the SDD formulations, natural log transformed AUCinf (if data permits), AUClast and Cmax
will be analyzed using a mixed effect model with sequence and treatment as fixed effects and 
participant within a sequence as a random effect. Estimates of the adjusted mean differences 
(Test-Reference) and corresponding 90% CIs will be obtained from the model. The adjusted 
mean differences and 90% CIs for the differences will be exponentiated to provide estimates 
of the ratio of adjusted geometric means (Test/Reference) and 90% CI for the ratios. 
Treatment A will be the Reference treatment while Treatments D and E will be the Test 
treatments. PK parameters, including plasma AUCinf (if data permits), AUClast,Cmax, and
Tmax, t½(if data permits) of PF-07321332 will be summarized descriptively by treatment and 
Day. For AUCinf (if data permits), AUClast and Cmax, a listing of the individual participant 
ratios (Test/Reference) will be provided. Box and whisker plots for AUCinf (if data permits), 
AUClast and Cmax, will be plotted by treatment.
The plasma concentrations of PF-07321332 will be listed and descriptively summarized by 
nominal PK sampling time and treatment. Individual participant, as well as mean and median 
profiles of the plasma concentration time data will be plotted by treatment using actual (for 
individual) and nominal (for mean and median) times respectively. Mean and median profiles 
will be presented on both linear and semi-log scales. 
Additional specifications about the tables, listings, and figures will be outlined in the SAP.
9.3.3. Other Safety Analyses
All safety analyses will be performed on the safety population.
AEs, ECGs, BP, PR, and safety laboratory data will be reviewed and summarized on an 
ongoing basis during the study to evaluate the safety of participants. Any clinical laboratory, 
ECG, BP, and PR abnormalities of potential clinical concern will be described. Safety data 
will be presented in tabular and/or graphical format and summarized descriptively, where 
appropriate.
Medical history and PE and neurological examination information, as applicable, collected 
during the course of the study will be considered source data and will not be required to be 

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reported, unless otherwise noted. However, any untoward findings identified on physical 
and/or neurological examinations conducted during the active collection period will be 
captured as AEs, if those findings meet the definition of an AE. Data collected at Screening 
that are used for inclusion/exclusion criteria, such as laboratory data, ECGs, and vital signs, 
will be considered source data, and will not be required to be reported, unless otherwise 
noted. Demographic data collected at Screening will be reported.
 
9.4. Interim Analyses
No formal interim analysis will be conducted for this study. As this is an open-label
study, the sponsor may conduct unblinded reviews of the data during the course of the study 
for the purpose of safety assessment, facilitating PK/PD modeling, and/or supporting clinical 
development.
9.5. Sample Size Determination
A sample size of 12 participants per cohort will provide adequate precision to estimate the 
relative bioavailability and intrasubject variability PF-07321332. The following table 
presents the width of 90% confidence interval for different estimated effects, with 80% 
coverage probability.
Parameter
Estimated Effect
(100*Test/Reference)
90% CI
CI Width
Cmax
85%
78.25%
92.33%
14.08%
90%
82.85%
97.76%
14.91%
95%
87.46%
103.19%
15.73%
100%
92.06%
108.62%
16.56%
105%
96.66%
114.05%
17.39%
110%
101.27%
119.49%
18.22%
115%
105.87%
124.92%
19.05%
AUC
85%
74.87%
96.49%
21.62%
90%
79.28%
102.17%
22.89%
95%
83.68%
107.85%
24.16%
100%
88.09%
113.52%
25.44%
105%
92.49%
119.20%
26.71%
110%
96.90%
124.88%
27.98%
115%
101.30%
130.55%
29.25%
These estimates are based on the assumption that within-participant standard deviations 
are 0.161and 0.105 for lnAUCinf  and lnCmax, respectively, 
 
.
CCI
CCI

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Participants who withdraw from the study or discontinue treatment, or whose PK samples are 
considered to be non-evaluable with respect to the primary PK objective may be replaced at 
the discretion of the investigator upon consultation with the sponsor.

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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 (if applicable), European Medical Device Regulation 
2017/745 for clinical device research (if applicable), 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. Informed Consent Process
The investigator or his/her representative will explain the nature of the study, including the 
risks and benefits, to the participant and answer all questions regarding the study. The 
participant 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 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 study participant 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 must be informed that his/her 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.
The participant must be informed that his/her 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 is fully informed about his or 
her right to access and correct his or her personal data and to withdraw consent for the 
processing of his or her personal data.
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 must be reconsented to the most current version of the ICD(s) during their 
participation in the study.
A copy of the ICD(s) must be provided to the participant.
A participant who is rescreened is not required to sign another ICD if the rescreening occurs 
within 10 days from the previous ICD signature date.

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10.1.3. 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 his or her 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.
10.1.4. Committees Structure
10.1.4.1. Data Monitoring Committee 
This study will not use a DMC.
10.1.5. 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, and/or 
www.pfizer.com, and other public registries 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.

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EudraCT
Pfizer posts clinical trial results on EudraCT for Pfizer-sponsored interventional studies in 
accordance with the format and timelines set forth by EU requirements.
www.pfizer.com
Pfizer posts public disclosure synopses (CSR synopses in which any data that could be used 
to identify individual participants have been removed) on www.pfizer.com for 
Pfizer-sponsored interventional studies at the same time the corresponding study results are
posted to www.clinicaltrials.gov.
Documents within marketing authorization packages/submissions
Pfizer complies with the European Union Policy 0070, the proactive publication of clinical 
data to the EMA website. Clinical data, under Phase 1 of this policy, includes clinical 
overviews, clinical summaries, CSRs, and appendices containing the protocol and protocol 
amendments, sample CRFs, and statistical methods. Clinical data, under Phase 2 of this 
policy, includes the publishing of individual participant data. Policy 0070 applies to new 
marketing authorization applications submitted via the centralized procedure since 
01 January 2015 and applications for line extensions and for new indications submitted via 
the centralized procedure since 01 July 2015.
Data sharing
Pfizer provides researchers secure access to patient-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 
24 months after study completion. Patient-level data will be anonymized in accordance with 
applicable privacy laws and regulations. CSRs will have personally identifiable information 
redacted.
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.
10.1.6. 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.

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The investigator must ensure that the CRFs are securely stored at the study site in encrypted 
electronic and/or paper form and are password-protected or secured in a locked room to 
prevent access by unauthorized third parties.
The investigator must permit study-related monitoring, audits, IRB/EC review, and 
regulatory agency inspections and provide direct access to source data 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 [IQMP] 
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.
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.
10.1.7. 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.

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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 source data and its origin can be found the Source Document 
Locator, which is maintained by the the sponsor’s designess (Pfizer Clinical Research Unit).
Description of the use of the computerized system is documented in the Source Document 
Locator, which is maintained by the sponsor’s designee (Pfizer Clinical Research Unit).
The investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF.
Study monitors will perform ongoing source data verification 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.
10.1.8. Study and Site Start and Closure
The study start date is the date on which the clinical study will be open for recruitment of 
participants.
The first act of recruitment is the date of the first participant’s first visit and will be the study 
start date.
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. 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 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.

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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.
10.1.9. Publication Policy
The results of this study may be published or presented at scientific meetings by the 
investigator after publication of the overall study results or 1 year after the end of the study 
(or study termination), whichever comes first. 
The investigator agrees to refer to the primary publication in any subsequent publications,
such as secondary manuscripts, and submits all manuscripts or abstracts to the sponsor 
30 days before submission. This allows the sponsor 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- or Pfizer-intervention 
related information necessary for the appropriate scientific presentation or understanding of 
the study results.
For all publications relating to the study, the investigator will comply with recognized ethical 
standards concerning publications and authorship, including those established by the 
International Committee of Medical Journal Editors.
The sponsor will comply with the requirements for publication of the overall study results 
covering all investigator sites. In accordance with standard editorial and ethical practice, the 
sponsor will support publication of multicenter studies only in their entirety and not as 
individual site data. In this case, a coordinating investigator will be designated by mutual 
agreement.
Authorship of publications for the overall study results will be determined by mutual 
agreement and in line with International Committee of Medical Journal Editors authorship 
requirements. 
If publication is addressed in the clinical study agreement, the publication policy set out in 
this section will not apply.
10.1.10. Sponsor’s Qualified Medical Personnel
The contact information for the sponsor's appropriately qualified medical personnel for the 
study is documented in the study contact list located in CTMS
To facilitate access to appropriately qualified medical personnel for study-related medical 
questions or problems, participants are provided with an Emergency Contact Card (ECC) at 

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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.
The ECC is intended to augment, not replace, the established communication pathways 
between the investigator, site staff, and study team. The ECC is to be used by healthcare 
professionals not involved in the research study only, as a means of reaching the investigator 
or site staff related to the care of a participant. 

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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 3.
Protocol-Required Safety Laboratory Assessments
Hematology
Chemistry
Urinalysis
Other
Hemoglobin
Hematocrit
RBC count
MCV
MCH
MCHC
Platelet count
WBC count
Total neutrophils 
(Abs)
Eosinophils (Abs)
Monocytes (Abs)
Basophils (Abs)
Lymphocytes (Abs)
BUN and creatinine
Glucose (fasted)
Calcium
Sodium
Potassium
Chloride
Total CO2 (bicarbonate)
AST, ALT
Total bilirubin
Alkaline phosphatase
Uric acid
Albumin
Total protein
Local Dipstick:
pH
Glucose (qual)
Protein (qual)
Blood (qual)
Ketones
Nitrites
Leukocyte esterase
Laboratory:
Microscopy and 
Culturea
•
SARS-CoV-2 RT-PCR
•
Urine drug screeningb
•
Pregnancy test (β-hCG)c
•
eGFR [CKD-EPI]
•
aPTT
•
PT-INR
•
Fibrinogen
At Screening only:
•
FSHd
•
HBsAg
•
HBsAbe
•
HBcAb
•
HCVAb
•
HIV
a.
Only if urine dipstick is positive for blood, protein, nitrites, or leukocyte esterase and culture only if bacteriuria.
b.
The minimum requirement for drug screening includes cocaine, THC, opiates/opioids, benzodiazepines, and 
amphetamines (others are site and study specific).
c.
Serum or urine β-hCG for female participants of childbearing potential.
d.
For confirmation of postmenopausal status only.
e.
HBsAb will be tested if HBsAg &/or HBcAb are positive.
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.
Any remaining serum/plasma from samples collected for clinical safety laboratory 
measurements at baseline and at all times after dose administration may be retained and 
stored for the duration of the study. Upon completion of the study, these retained safety 
samples may be used for the assessment of 
 unexpected 
safety findings. These data will not be included in the CSR. Samples to be used for this 
purpose will be shipped to either a Pfizer-approved BBS facility or other designated 
laboratory and retained for up to 1 year following the completion of the study.
CCI

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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 either 
an increase in 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 non-pathogenic, is considered serious.
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.
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. 

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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/SAEs associated 
with exposure during 
pregnancy or breastfeeding
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 non-
participant (not 
involving EDP or EDB).
None. Exposure to a study 
non-participant 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 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. 

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.

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
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: 

Mild: Asymptomatic or mild symptoms; clinical or diagnostic observations only; 
intervention not indicated.

Moderate: Minimal, local or noninvasive intervention indicated; limiting age-
appropriate instrumental ADL. Instrumental ADL refers to preparing meals, 
shopping for groceries or clothes, using the telephone, managing money, etc.

Severe: Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling, limiting 
self care ADL. Self care ADL refers to bathing, dressing and undressing, feeding 
self, using the toilet, taking medications, and not bedridden.
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 his/her assessment.

For each AE or SAE, the investigator must document in the medical notes that 
he/she has reviewed the AE or SAE and has 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 his/her 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 Tool

The primary mechanism for reporting an SAE to Pfizer Safety will be the 
electronic data collection tool.

If the electronic system is unavailable, then the site will use the paper SAE data 
collection tool (see next section) to report the event within 24 hours.

The site will enter the SAE data into the electronic system as soon as the data
become available.

After the study is completed at a given site, the electronic data collection tool 
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 data collection 
tool 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 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, 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 with a female of childbearing potential 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 woman of childbearing 
potential 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
A female participant is eligible to participate if she is not pregnant or breastfeeding, and at 
least 1 of the following conditions applies:

Is not a WOCBP (see definitions below in Section 10.4.3).
OR

Is a WOCBP and using a contraceptive method that is highly effective (with a failure 
rate of <1% per year), as described below, 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). If a 
highly effective method that is user dependent is chosen, a second effective method of 
contraception, as described below, must also be used. The investigator should 
evaluate the effectiveness of the contraceptive method in relationship to the first dose 
of study intervention.

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The investigator is responsible for review of medical history, menstrual history, and recent 
sexual activity to decrease the risk for inclusion of 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 an alternate 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.
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 old 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 nonestrogen hormonal highly effective contraception methods 
if they wish to continue their HRT during the study. Otherwise, they must 
discontinue HRT to allow confirmation of postmenopausal status before study 
enrollment.

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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.
1. Implantable progestogen only hormone contraception associated with inhibition of 
ovulation.
2. Intrauterine device.
3. Intrauterine hormone releasing system.
4. Bilateral tubal occlusion (eg, bilateral tubal ligation).
5. Vasectomized partner.

A vasectomized partner is a highly effective contraceptive method provided that 
the partner is the sole sexual partner of the woman of childbearing potential 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.
6. Combined (estrogen  and progestogen containing) hormonal contraception associated 
with inhibition of ovulation.

Oral;

Intravaginal;

Transdermal;
7. Progestogen only hormone contraception associated with inhibition of ovulation.

Oral;

Injectable.
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.

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In addition, one of the following effective barrier methods must also be used when 
option 6 or 7 are chosen above:

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).
Because ritonavir may reduce the effect of estradiol-containing contraceptives when agents
are coadministered, a barrier method or other nonhormonal method of contraception must
also be used if the participant is using estradiol-containing contraceptives. 

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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 multistudy 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
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 enzyme 
elevations but adapt are termed “adaptors.” In some participants, transaminase elevations are 
a harbinger of a more serious potential outcome. Participants who experience a transaminase 
elevation above 3 × ULN should be monitored more frequently to determine if they are 
“adaptors” or are “susceptible.”
Abnormal elevations in either AST OR ALT in addition to TBili that meet the criteria 
outlined below need to be evaluated for causality 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 depends on the participant’s individual baseline 
values and underlying conditions. Participants who present with the following laboratory 
abnormalities should halt/stop dosing and be evaluated for causality to definitively determine 
the etiology of the abnormal laboratory values:

Participants with AST/ALT and TBili baseline values within the normal range who 
subsequently present with AST OR ALT values >3 × ULN AND a TBili 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 TBili 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 TBili above the normal range: TBili level increased from 
baseline value by an amount of at least 1 × ULN or if the value reaches 
>3 × ULN (whichever is smaller).
Rises in AST/ALT and TBili 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 for causality 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. If on further 
evaluation the abnormal test result is repeated, the participant should be discontinued from 
the study and adequate, immediate, supportive measures taken.

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In addition to repeating measurements of AST and ALT and TBili for suspected liver toxicity
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 
TBili elevation defined above should be considered potential DILI cases if no other reason 
for the LFT abnormalities has yet been found. Such potential DILI 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 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: 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 msec.

New prolongation of QTcF to >480 msec (absolute) or by ≥60 msec 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 msec.

New ST-T changes suggestive of myocardial ischemia.

New-onset left bundle branch block (QRS >120 msec).

New-onset right bundle branch block (QRS >120 msec).

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 
(heart rate <40 bpm), accelerated idioventricular rhythm (PR >40 bpm to
<100 bpm), and monomorphic/polymorphic ventricular tachycardia (PR 
>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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10.8. Appendix 8: Abbreviations
The following is a list of abbreviations that may be used in the protocol.
Abbreviation
Term
ongoing/continuous event
19F-NMR
19F nuclear magnetic resonance
3CLpro
3C-like protein
Abs
absolute
ADL
activities of daily living
AE
adverse event
AESI
adverse events of special interest
ALT
alanine aminotransferase
API
active pharmaceutical ingredient
aPTT
activated partial thromboplastin time
AST
aspartate aminotransferase
AUC
area under the concentration-time curve
AUCinf
area under the concentration-time curve from time zero 0 
extrapolated to infinity
AUClast
area under the plasma concentration-time curve from time 0 to the 
time of the last measurable concentration
AV
atrioventricular
BBS
Biospecimen Banking System
-hCG
‑human chorionic gonadotropin
BID
twice a day
BMI
body mass index
BP
blood pressure
bpm
beats per minute
BUN
blood urea nitrogen
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 Collaboration
CL/F
apparent clearance of drug from eg, plasma
Clast
last quantifiable concentration
Cmax
maximum observed concentration
CO2
carbon dioxide (bicarbonate)
COVID-19
coronavirus disease 2019
CRF
case report form
CRO
contract research organization
CRU
clinical research unit
CSR
clinical study report

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Abbreviation
Term
CT
clinical trial
CTMS
Clinical Trial Management System
CYP
cytochrome P450 
CYP3A
cytochrome P450, family 3, subfamily A
CYP3A4
cytochrome P450 3A4 
CYP3A5
cytochrome P450 3A5 
DILI
drug‑induced liver injury
DMC
data monitoring committee
DNA
deoxyribonucleic acid
EC
ethics committee
ECC
emergency contact card
ECG
electrocardiogram
eCRF
electronic case report form
EDB
exposure during breastfeeding
EDP
exposure during pregnancy
EDR
extemporaneous dispensing record
eGFR
estimated glomerular filtration rate
EMA
European Medicines Agency
EU
European Union
EudraCT
European Clinical Trials Database
FIH
first in human
fm
fraction metabolized
FSH
follicle‑stimulating hormone
GCP
Good Clinical Practice
GGT
gamma‑glutamyl transferase
GLP
Good Laboratory Practice
HBcAb
hepatitis B core antibody
HBsAb
hepatitis B surface antibody
HBsAg 
hepatitis B surface antigen
HCVAb
hepatitis C antibody
HPLC‑MS/MS 
high-performance liquid chromatography mass spectrometry
HRT
hormone replacement therapy
IB
investigator’s brochure
ICD
informed consent document
ICH
International Council for Harmonisation
ID
identification
lnAUCinf
log-transformed AUCinf
lnCmax
log-transformed Cmax
IND
investigational new drug 
IPAL
Investigational Product Accountability Log
IQMP
Integrated Quality Management Plan
IRB
institutional review board

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Abbreviation
Term
IV
intravenous
Kel
elimination rate constant
Ki
inhibition constant
LBBB
left bundle branch block
LFT
liver function test
Loge
natural logarithm
LFT
liver function test
MAD
multiple ascending dose
MCH
mean corpuscular hemoglobin
MCHC
mean corpuscular hemoglobin concentration
MCV
mean corpuscular volume
msec
millisecond
N/A
not applicable
NOAEL
no‑observed‑adverse‑effect level
NSAE
non-serious adverse event
NYHA
New York Heart Association
PCRU
Pfizer clinical research unit
PD
pharmacodynamics
PE
physical examination 
PK
pharmacokinetic(s)
PR
pulse rate
PT-INR
prothrombin time-international normalized ratio
PVC
premature ventricular contraction/complex
q12h
every 12 hours
QTc
corrected QT
QTcF
corrected QT (Fridericia method)
qual
qualitative
rBA
relative bioavailablity
RBC
red blood cell
RT-PCR
reverse-transcriptase polymerase chain reaction
SAD
single ascending dose
SAE
serious adverse event
SAP
statistical analysis plan
SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
SCr
serum creatinine
SD
standard deviation
SDD
spray dried dispersion
SoA
schedule of activities
SOC
system organ class
SOP
standard operating procedure
SRSD
single reference safety document
SUSAR
suspected unexpected serious adverse reaction

PF-07321332 
Protocol C4671008
Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
Page 86
Abbreviation
Term
t½
terminal half‑life
TBiLi
total bilirubin
TEAE
treatment emergent adverse event
THC
tetrahydrocannabinol
Tmax
time to maximum concentration
TSH
thyroid stimulating hormone
UHPLC-HRMS/MS
ultra high-performance liquid chromatography/high resolution mass 
spectrometry
ULN
upper limit of normal
US
United States
USPI
United States Package Insert
Vz/F
apparent volume of distribution
WBC
white blood cell
WHO
World Health Organization
WOCBP
woman/women of childbearing potential

PF-07321332 
Protocol C4671008
Final Protocol Amendment 1, 08 Feburary 2022
PFIZER CONFIDENTIAL
Page 87
11. REFERENCES
1
World Health Organization. WHO Situation Report –51 Coronavirus disease 2019 
(COVID-19). 11 March 2020. Available from: 
https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports. 
Accessed: 29 March 2020.
2
Investigator’s Brochure, PF-07321332. (Version 4.0)

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