Conditions: Bioavailability
Keywords: coronavirus disease 2019 (COVID-19) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Nirmatrelvir
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 12
Healthy volunteers: yes

Brief summary:
The purpose of this study is to estimate the relative bioavailability of PF-07321332/ritonavir oral powder relative to the commercial tablet formulation under fasted condition in healthy adult participants. The study will also assess the effect of 3 different food vehicles on the relative bioavailability of the PF-07321332/ritonavir oral powder formulation as well as the safety, tolerability, and palatability of PF-07321332/ritonavir oral powder in healthy adult participants.

Detailed description:

Arms:
arm 1: PF-07321332 ritonavir arm 2: PF-07321332/ritonavir mixed with water arm 3: PF-07321332/ritonavir mixed with applesauce arm 4: PF-07321332/ritonavir mixed with vanilla pudding

Interventions: intervention 1: PF-07321332/ritonavir intervention 2: PF-07321332/ritonavir intervention 3: PF-07321332/ritonavir intervention 4: PF-07321332/ritonavir
Intervention descriptions: intervention 1: Single oral dose of PF-07321332/ritonavir under fasted conditions intervention 2: Single oral dose of PF-07321332/ritonavir mixed with water under fasted conditions intervention 3: Single oral dose of PF-07321332/ritonavir mixed with applesauce under fasted conditions intervention 4: Single oral dose of PF-07321332/ritonavir mixed with vanilla pudding under fasted conditions

Protocol document:
Prot_000.pdf: 
PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 1
A PHASE 1, OPEN-LABEL, RANDOMIZED, SINGLE-DOSE, CROSSOVER STUDY 
TO ESTIMATE THE RELATIVE BIOAVAILABILITY OF 
PF-07321332/RITONAVIR ORAL POWDER IN 3 DIFFERENT DELIVERY 
VEHICLES RELATIVE TO THE COMMERCIAL PF-07321332/RITONAVIR 
TABLETS IN HEALTHY ADULT PARTICIPANTS UNDER FASTED CONDITIONS
Study Intervention Number:
PF-07321332
Study Intervention Name:
NA
US IND Number:
EudraCT Number:
NA
ClinicalTrials.gov ID: 
NA
Protocol Number:
C4671024
Phase:
1
Brief Title: A Phase 1 Relative Bioavailability Study of PF-07321332/Ritonavir Oral 
Powder Relative to the Commercial Tablets 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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PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
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Document History
Document
Version Date
Original protocol
09 February 2022


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 3
TABLE OF CONTENTS
LIST OF TABLES.....................................................................................................................7
1. PROTOCOL SUMMARY.....................................................................................................8
1.1. Synopsis ....................................................................................................................8
1.2. Schema ....................................................................................................................13
1.3. Schedule of Activities .............................................................................................14
2. INTRODUCTION ...............................................................................................................17
2.1. Study Rationale .......................................................................................................17
2.2. Background .............................................................................................................17
2.2.1. Nonclinical Pharmacology..........................................................................17
2.2.2. Nonclinical Pharmacokinetics and Metabolism .........................................17
2.2.3. Nonclinical Safety ......................................................................................18
2.2.4. Clinical Overview.......................................................................................18
2.2.4.1. Safety Overview........................................................................19
2.2.4.2. Summary of PF-07321332 Pharmacokinetics in Human..........19
2.3. Benefit/Risk Assessment.........................................................................................20
3. OBJECTIVES AND ENDPOINTS.....................................................................................22
4. STUDY DESIGN.................................................................................................................23
4.1. Overall Design.........................................................................................................23
4.2. Scientific Rationale for Study Design.....................................................................24
4.2.1. Choice of Contraception/Barrier Requirements .........................................24
4.2.2. Collection of Retained Research Samples..................................................25
4.3. Justification for Dose ..............................................................................................25
4.4. End of Study Definition ..........................................................................................25
5. STUDY POPULATION......................................................................................................25
5.1. Inclusion Criteria.....................................................................................................25
5.2. Exclusion Criteria....................................................................................................26
5.3. Lifestyle Considerations..........................................................................................29
5.3.1. Meals and Dietary Restrictions...................................................................29
5.3.2. Caffeine, Alcohol, and Tobacco .................................................................29
5.3.3. Activity .......................................................................................................30


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Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
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5.3.4. Contraception..............................................................................................30
5.4. Screen Failures ........................................................................................................30
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY.................................30
6.1. Study Intervention(s) Administered........................................................................31
6.1.1. Administration............................................................................................31
6.2. Preparation, Handling, Storage, and Accountability...............................................31
6.2.1. Preparation and Dispensing........................................................................32
6.3. Measures to Minimize Bias: Randomization and Blinding.....................................33
6.3.1. Allocation to Study Intervention ................................................................33
6.4. Study Intervention Compliance...............................................................................33
6.5. Dose Modification...................................................................................................33
6.6. Continued Access to Study Intervention After the End of the Study......................33
6.7. Treatment of Overdose............................................................................................33
6.8. Concomitant Therapy..............................................................................................34
6.8.1. Rescue Medicine.........................................................................................35
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL...........................................................................35
7.1. Discontinuation of Study Intervention ....................................................................35
7.1.1. ECG Changes..............................................................................................35
7.1.2. Potential Cases of Acute Kidney Injury .....................................................35
7.1.3. Stopping Rules............................................................................................36
7.2. Participant Discontinuation/Withdrawal From the Study.......................................36
7.2.1. Withdrawal of Consent...............................................................................37
7.3. Lost to Follow-up....................................................................................................38
8. STUDY ASSESSMENTS AND PROCEDURES...............................................................38
8.1. Efficacy Assessments..............................................................................................39
8.2. Safety Assessments .................................................................................................39
8.2.1. Physical Examinations................................................................................39
8.2.2. Vital Signs ..................................................................................................40
8.2.2.1. Temperature ..............................................................................40
8.2.3. Electrocardiograms.....................................................................................40
8.2.4. Clinical Safety Laboratory Assessments ....................................................41


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PFIZER CONFIDENTIAL
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8.2.5. COVID-19 Specific Assessments...............................................................42
8.2.6. Pregnancy Testing ......................................................................................42
8.3. Adverse Events, Serious Adverse Events, and Other Safety Reporting .................42
8.3.1. Time Period and Frequency for Collecting AE and SAE Information.......42
8.3.1.1. Reporting SAEs to Pfizer Safety...............................................43
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF...................43
8.3.2. Method of Detecting AEs and SAEs ..........................................................43
8.3.3. Follow-Up of AEs and SAEs......................................................................44
8.3.4. Regulatory Reporting Requirements for SAEs...........................................44
8.3.5. Environmental Exposure, Exposure During Pregnancy or 
Breastfeeding, and Occupational Exposure.....................................................44
8.3.5.1. Exposure During Pregnancy......................................................45
8.3.5.2. Exposure During Breastfeeding ................................................46
8.3.5.3. Occupational Exposure .............................................................47
8.3.6. Cardiovascular and Death Events...............................................................47
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs..............................................................................47
8.3.8. Adverse Events of Special Interest.............................................................47
8.3.8.1. Lack of Efficacy........................................................................47
8.3.9. Medical Device Deficiencies......................................................................47
8.3.10. Medication Errors.....................................................................................47
8.4. Pharmacokinetics ....................................................................................................48
8.4.1. Plasma for Analysis of PF-07321332 and Ritonavir..................................48
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8.7. Immunogenicity Assessments.................................................................................50
8.8. Health Economics ...................................................................................................51
8.9. Taste Assessment of PF-07321332 Suspension......................................................51
9. STATISTICAL CONSIDERATIONS ................................................................................51
9.1. Statistical Hypotheses .............................................................................................51
9.2. Analysis Sets ...........................................................................................................51
9.3. Statistical Analyses .................................................................................................52
9.3.1. Pharmacokinetic Analyses..........................................................................52
9.3.1.1. Derivation of Pharmacokinetic Parameters...............................52
9.3.2. Statistical Methods for PK Data .................................................................53
9.3.3. Other Safety Analyses ................................................................................53
9.3.4. Other Analyse(s).........................................................................................54
9.3.4.1. Taste Assessment ......................................................................54
9.4. Interim Analyses .....................................................................................................54
9.5. Sample Size Determination.....................................................................................54
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS..........................................................................................................56
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations...............56
10.1.1. Regulatory and Ethical Considerations ....................................................56
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP.........................................................................56
10.1.2. Financial Disclosure .................................................................................57
10.1.3. Informed Consent Process ........................................................................57
10.1.4. Data Protection .........................................................................................58
10.1.5. Committees Structure ...............................................................................58
10.1.5.1. Data Monitoring Committee ...................................................58
10.1.6. Dissemination of Clinical Study Data ......................................................58
10.1.7. Data Quality Assurance ............................................................................59
10.1.8. Source Documents....................................................................................61
10.1.9. Study and Site Start and Closure ..............................................................61
10.1.10. Publication Policy...................................................................................62
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10.1.11. Sponsor’s Qualified Medical Personnel .................................................63
10.2. Appendix 2: Clinical Laboratory Tests .................................................................64
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting .....................................................................65
10.3.1. Definition of AE .......................................................................................65
10.3.2. Definition of an SAE ................................................................................66
10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During 
the Active Collection Period............................................................................67
10.3.4. Reporting of SAEs....................................................................................71
10.4. Appendix 4: Contraceptive and Barrier Guidance ................................................72
10.4.1. Male Participant Reproductive Inclusion Criteria....................................72
10.4.2. Female Participant Reproductive Inclusion Criteria.................................72
10.4.3. Woman of Childbearing Potential ............................................................73
10.4.4. Contraception Methods.............................................................................74
10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments .......77
10.7. Appendix 7: ECG Findings of Potential Clinical Concern ...................................79
10.8. Appendix 8: Palatability Questionnaire ................................................................81
10.9. Appendix 9: Abbreviations ...................................................................................89
11. REFERENCES ..................................................................................................................93
LIST OF TABLES
Table 1.
Randomized Treatment Sequences...........................................................23
Table 2.
Plasma PF-07321332 and Ritonavir PK Parameters Definitions .............52
Table 3.
Protocol-Required Safety Laboratory Assessments .................................64
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PFIZER CONFIDENTIAL
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1. PROTOCOL SUMMARY 
1.1. Synopsis 
Brief Title: A Phase 1 Relative Bioavailability Study of PF-07321332/Ritonavir Oral 
Powder Relative to the Commercial Tablets in Healthy Participants.
Rationale
PF-07321332 is a potent and selective inhibitor of the SARS-CoV-2 Mpro 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 efficacious. The clinical development 
program for PF-07321332 includes 8 completed clinical studies: five Phase 1 studies in 
healthy participants (C4671001, C4671012, C4671013, C4671014 and C4671015), one
Phase 1 study in renal impairment participants (C4671011), one Phase 1 study in hepatic 
impairment participants (C4671010) and one Phase 2/3 pivotal study in COVID-19 patients 
(C4671005).
The purpose of this study is to estimate the rBA of PF-07321332/ritonavir oral powder 
relative to the commercial tablet formulation under fasted condition in healthy adult 
participants. The study will also assess the effect of 3 different food vehicles on the rBA of 
the PF-07321332/ritonavir oral powder formulation as well as the safety, tolerability, and 
palatability of PF-07321332/ritonavir oral powder in healthy adult participants.


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 9
Objectives and Endpoints 
Primary Objective: 
Primary Endpoint: 
•
To estimate the rBA of the 
PF-07321332/ritonavir 300 mg/100 mg oral 
powder mixed with water compared to the 
PF-07321332/ritonavir commercial tablets under 
fasted conditions.
•
To estimate the rBA of the 
PF-07321332/ritonavir 300 mg/100 mg oral 
powder mixed with applesauce compared to the 
PF-07321332/ritonavir commercial tablets under 
fasted conditions.
•
To estimate the rBA of the 
PF-07321332/ritonavir 300 mg/100 mg oral 
powder mixed with vanilla pudding compared to 
the PF-07321332/ritonavir commercial tablets
under fasted conditions.
•
The ratio of AUClast, AUCinf (if data permits) 
and Cmax of PF-07321332 and ritonavir.
Secondary Objective: 
Secondary Endpoints: 
•
To evaluate the safety and tolerability of 
PF-07321332/ritonavir in healthy participants.
•
To assess the palatability of 
PF-07321332/ritonavir oral powder mixed with 
water/applesauce/vanilla pudding.
•
Assessment of TEAEs, clinical laboratory 
abnormalities, vital signs, PEs, and 12-lead 
ECGs.
•
Assessment of palatability using via 
questionnaire: mouth feel, bitterness, 
tongue/mouth burn, throat burn and overall 
liking.
 
 
 
 
 
 
 
 
 
 
 
 
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PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
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Overall Design
Brief Summary
This is a Phase 1, open-label, single-dose, randomized, crossover study in healthy adult 
participants to estimate rBA of PF-07321332/ritonavir 300 mg/100 mg oral powder mixed 
with 3 different delivery vehicles (Test formulations) compared to the PF-07321332/ritonavir
commercial tablets (Reference formulation) under fasted conditions. The study will also
assess the safety, tolerability, and palatability of PF-07321332/ritonavir oral powder in 
healthy adult participants.
The study will consist of 4 treatments: a single oral dose of PF-07321332/ritonavir 
300 (2 × 150 mg)/100 mg tablets (Treatment A), a single oral dose of PF-07321332/ritonavir 
300 mg/100 mg oral powder mixed in water (Treatment B), a single oral dose of 
PF-07321332/ritonavir 300 mg/100 mg oral powder mixed in applesauce (Treatment C) and 
a single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder mixed in vanilla 
pudding (Treatment D). All treatments will be administered under fasted condition. Between 
each treatment, a minimum of 4 days washout is proposed to minimize any residual 
PF-07321332 and ritonavir concentrations prior to start of the next treatment.
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 PEs, vital signs, 12-lead ECGs, and clinical 
laboratory evaluations will determine eligibility. Eligible participants will be admitted to the 
PCRU on Day -1 and will be confined in the PCRU until discharge which is Day 4 of 
Period 4.
On Day 1 of each period, participants will receive a single oral dose of study interventions
PF-07321332/ritonavir 300 mg/100 mg as per the randomization schedule. 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 PCRU on 
Period 4, 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 PCRU
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.


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Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 11
Number of Participants
Approximately 12 participants will be randomly assigned to study intervention such that 
approximately 3 participants will be enrolled into 1 of 4 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.
Intervention Groups and Duration
Each enrolled participant will participate in 4 study periods to receive 4 different treatments 
according to the sequence determined by randomization: 

Treatment A: Single oral dose of PF-07321332/ritonavir 300 mg 
(2 × 150 mg)/100 mg commercial tablets under fasted conditions (Reference)

Treatment B: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with water under fasted conditions (Test 1) 

Treatment C: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with applesauce under fasted conditions (Test 2) 

Treatment D: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder
mixed with vanilla pudding under fasted conditions (Test 3) 
Participants will be randomly assigned to 1 of 4 sequences as below: 
Treatment
Period 1
Period 2
Period 3
Period 4
Sequence 1 (N =3)
Treatment A
Treatment B
Treatment C
Treatment D
Sequence 2 (N =3)
Treatment B
Treatment D
Treatment A
Treatment C
Sequence 3 (N =3)
Treatment C
Treatment A
Treatment D
Treatment B
Sequence 4 (N =3)
Treatment D
Treatment C
Treatment B
Treatment A
Between each treatment, a minimum of 4 days washout is proposed to minimize any residual 
PF-07321332 and ritonavir concentrations prior to start of the next treatment. Participants 
will be discharged on Day 4 of Period 4, following completion of all assessments. 
The total planned duration of participation from the Screening visit to the last follow-up 
phone call, is approximately 11 weeks.


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 12
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.
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 and ritonavir. 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 analysis set 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 set 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 and ritonavir will be analyzed using standard 
noncompartmental method of analysis. Actual PK sampling times will be used in the 
derivation of PF-07321332 and ritonavir PK parameters when available, otherwise nominal 
times will be used. The PF-07321332 and ritonavir 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 and ritonavir 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.
Palatability Assesment
Participants will be asked to fill out the Palatability Questionnaire after administration for 
Treatments B, C and D. The Palatability Questionnaire will be administered at 1 
(immediately after dosing), 5, 10, and 20 minutes after administration. Details about the 
Palatability Questionnaire are provided in Appendix 8 (Section 10.8).


PF-07321332 
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PFIZER CONFIDENTIAL
Page 13
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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Final Protocol 09 February 2022
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Page 14
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 9
Screeninga
Period 1
Period 2 and 3
Period 4
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1
1
2
3
4
1
2
3
4
1
2
3
4
28-35 
Daysb
Informed consent
X
CRU Confinementc
X
®
®
®
®
®
®
®
®
®
®
®
X
X
Inclusion/exclusion criteria
X
X
Medical/medication history (update)d
X
X
Demographye
X
PEf
X
X
Safety laboratoryg
X
X
X
X
FSHh
X
Urine drug testingi
X
X
Serology: HBsAg, HBsAb, HBcAb, 
HCVAb, and HIVj
X
Pregnancy test (WOCBP only)
X
X
X
X
Contraception checkk
X
X
X
12-lead ECG (single)l
X
Xm
X
X
Vital signs (BP/PR)n
X
X
X
X
X
X
COVID-19 questionnaireo
X
X
COVID-19 testingp
X
X
X
COVID-19 check temperatureq
X
X


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PFIZER CONFIDENTIAL
Page 15
Visit Identifier
Abbreviations used in this table may be 
found in Appendix 9
Screeninga
Period 1
Period 2 and 3
Period 4
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1
1
2
3
4
1
2
3
4
1
2
3
4
28-35 
Daysb
PF-07321332/ritonavir dosingr
X
X
X
Palatability Questionnaires
X
X
X
PK Blood Sampling for PF-07321332/ 
ritonavirt
X
X
X
X
X
X
X
X
X
X
X
X
X
 
 
 
Serious and nonserious AE monitoring
X
®
®
®
®
®
®
®
®
®
®
®
®
®
X
X
Concomitant treatments
X
X
X
®
®
®
®
®
®
®
®
®
®
X
X
CRU discharge
X
a.
Screening will be performed within 28 days prior to the first dose of PF-07321332/ritonavir. 
b.
Follow-up contact may occur via telephone contact and must occur 28 to 35 days from administration of the final dose of study intervention.
c.
Participants will be admitted to the CRU on Day -1. Participants will be discharged on Period 4 Day 4 following the final assessments.
d.
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. 
e.
Demographics will include participant race, ethnicity, age, and gender during the Screening visit. 
f.
PE 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. 
g.
Safety laboratory assessments including urinalysis, hematology, chemistry and coagulation will be performed at Screening, Period 1 Day -1, Period 4 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.
h.
For confirmation of postmenopausal (amenorrheic for at least 12 consecutive months) female participants.
i.
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.
j.
HBsAb will be tested if HBsAg and/or HBcAb are positive. 
k.
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.
l.
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.
m.
This will be done predose of Period 1 Day 1.
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Visit Identifier
Abbreviations used in this table may be 
found in Appendix 9
Screeninga
Period 1
Period 2 and 3
Period 4
Follow-Up
Early 
Termination/
Discontinuation
Days Relative to Day 1
Days
-28 to -2
Day -1
1
2
3
4
1
2
3
4
1
2
3
4
28-35 
Daysb
n.
Single supine BP and 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. Vital signs will be done predose of Period 1 Day 1, and 2 hours and 6 hours post 
dose on Day1 of each treatment period and also on Day 4 of Period 4. 
o.
Check exposure to positive participant, residence or travel in area of high incidence and COVID-19 related signs and symptoms. 
p.
The testing for COVID-19 pathogen by RT-PCR will be performed at the specified time points and an additional SARS-CoV-2 test will also be performed after 4 days (ie, 
upon completion of 4 × 24 hours in the PCRU), ie, Period 1 Day 4. Additional testing for COVID-19 pathogen will also be done as per local requirements or by the 
principle investigator.
q.
Temperature measurements may be done more frequently as clinically warranted.
r.
PF-07321332/ritonavir 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.
s.
Review taste questionnaire and instructions with participants prior to the first taste assessment to Treatment B, C, D, on Period 1, Day 1. Each participant will record the 
sensory attributes at timed intervals of 1 (immediately after dosing), 5, 10 and 20 minutes after swallowing the suspension, using a Taste Assessment Questionnaire (see 
Appendix 8)
t.
One (approximately 4 mL) blood sample for PK analysis of PF-07321332 and ritonavir will be taken at the designated time points. See PK sampling schema in table below.
 
 
Pharmacokinetic Sampling Schema
Visit Identifier
Treatment Period 1 to 4
Study Day
Day 1
Day 2
Day 3
Day 4
Planned Hours Post Dose on That 
Day
0
0.5
1
1.5
2
2.5
3
4
6
8
12
16
24
48
72
PK blood sampling for 
PF-07321332/ritonavir
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
CCI
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2. INTRODUCTION
PF-07321332 is a potent and selective inhibitor of the SARS-CoV-2 Mpro 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 efficacious. 
2.1. Study Rationale 
The purpose of this study is to estimate the rBA of PF-07321332/ritonavir oral powder in 3
different delivery vehicle relative to the commercial tablet formulation under fasted condition 
in healthy adult participants. The study will also assess the safety, tolerability, and 
palatability of PF-07321332/ritonavir oral powder in healthy adult participants. The study 
will be used to assess the microsampling technique and if acceptable, the technique can be 
used in future clinical trials to reduce patient burden. 
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 2020.1
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 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.
The clinical development program for PF-07321332 includes 8 completed clinical studies: 
five Phase 1 studies in healthy participants (C4671001, C4671012, C4671013, C4671014 and 
C4671015), one Phase 1 study in renal impairment participants (C4671011), one Phase 1 
study in hepatic impairment participants (C4671010) and one Phase 2/3 study in COVID-19 
patients (C4671005).
2.2.1. Nonclinical Pharmacology
Details of the nonclinical pharmacology of PF-07321332 can be found in the current IB2.
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 


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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
nonadverse, 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 
increase in ALT and/or AST and increase in fibrinogen at the high dose in 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, nonadverse 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.
2.2.4. Clinical Overview
Safety, tolerability and PK of PF-07321332 in healthy adult participants was explored in 
Phase 1 FIH Study (C4671001). Study C4671001 was a 5-part study consisting of SAD 
(PART-1), MAD (PART-2), relative bioavailability/food effect (PART-3), metabolism and 
excretion study (PART-4) and supratherapeutic exposure cohort (PART-5). PART-1 and -2 
are randomized, double-blind, sponsor-open, and placebo-controlled to evaluate safety, 
tolerability, and PK of single and multiple escalating oral doses of PF-07321332, 
respectively. PART-3 was randomized and open-label to evaluate relative bioavailability and 
food effect of an oral tablet formulation. PART-4 was an open-label, nonrandomized, 
single-period to evaluate the metabolism and excretion of PF-07321332. PART-5 was a 


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double-blind, sponsor-open, randomized, crossover study to evaluate safety and tolerability 
at supratherapeutic exposures.
Efficacy and safety of PF-07321332 was evaluated in interventional Phase 2/3 Study 
(C4671005). C4671005 was a Phase 2/3 randomized, placebo-controlled trial in 
nonhospitalized adult participants with a laboratory-confirmed diagnosis of SARS-CoV-2 
infection. Included in this Clinical Overview are summaries of the results of Study 
C4671001 and C4671005.
2.2.4.1. Safety Overview
In the completed Phase 1 studies in healthy participants and Phase 2/3 study in participants 
with a laboratory-confirmed diagnosis of SARS-CoV-2 infection, PF-07321332/ritonavir was 
generally safe and well tolerated.
Safety data from Study C4671001 indicate that PF-07321332 was safe and well tolerated in 
healthy adult participants at all the exposures tested including supratherapeutic exposure.
Current evidence indicates that the clinical safety profile of PF-07321332 is acceptable at 
single doses up to a 2250 mg dose administered as 3 split doses of 750 mg administered with 
ritonavir, and at repeated daily doses administered orally for 10 days of up to 500 mg 
PF-07321332 BID with 100 mg ritonavir BID. In all 5-parts of the study, there were no 
deaths, severe AEs, or SAEs. PF-07321332 alone or PF-07321332/ritonavir was generally 
safe and well tolerated in healthy participants in all parts including SAD, MAD, and SE 
cohorts. No notable safety findings were observed. All TEAEs were mild in severity, except 
for one AE which was moderate in severity, and not considered treatment related. Overall, 
there were no clinically meaningful laboratory changes, no clinically significant findings in 
vital sign measurements or 12-lead ECG assessments throughout this study. The safety data, 
including AEs, laboratory abnormalities, vital signs, and ECGs indicate that PF-07321332 
has an acceptable safety and tolerability profile in healthy adult participants.
C4671005 is a Phase 2/3 randomized, placebo-controlled trial in nonhospitalized adult 
participants with a laboratory-confirmed diagnosis of SARS-CoV-2 infection. A total of 2224 
symptomatic adult participants 18 years of age and older at high risk of developing severe 
disease received at least 1 dose of either nirmatrelvir/ritonavir (n=1,109) or placebo 
(n=1,115). Adverse events (all grades regardless of causality) in the nirmatrelvir/ritonavir
group (≥1%) that occurred at a greater frequency (≥5 participant difference) than in the 
placebo group were dysgeusia (6% and <1%, respectively), diarrhea (3% and 2%), 
hypertension (1% and <1%), and myalgia (1% and <1%).
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
 
 
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 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 coadministered 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 suggest 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.
 
PF-07321332 plasma exposure for the tablet treatment was lower compared to the 
suspension, with approximately 19% and 44% lower geometric mean AUClast and Cmax
values, respectively.
The effect of food (eg, high-fat high-calorie meal) on exposures of PF-07321332 after oral 
administration of a suspension of PF-07321332, enhanced with 100 mg ritonavir, resulted in 
approximately 1.5% increase in AUCinf and 15% increase in Cmax of PF-07321332.
The primary route of elimination of PF-07321332 when administered with ritonavir was 
renal excretion of intact drug. A total of 49.6% and 35.3% of the administered dose of 
PF-07321332 300 mg was recovered in urine and feces, respectively. PF-07321332 was the 
predominant drug-related entity with small amounts of metabolites arising from hydrolysis 
reactions in excreta. After normalization of the data to 100% mass balance, unmetabolized 
PF-07321332 represented 82.5% of the drug-related material, with 55.0% in urine and 27.5% 
in feces. In plasma, the only drug-related entity quantifiable 19F-NMR was unchanged 
PF-07321332.
Further details on the clinical PK of PF-07321332 are provided in the current IB2.
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.
Based on data from Study C4671001 and C4671005, the clinical safety profile of 
PF-07321332 appears to be acceptable at single doses up to 1500 mg alone and up to 
2250 mg administered with ritonavir (100 mg at -12h, 0h, 12h), split dosing administration (3 
doses of 750 mg) at short intervals (approximately 2 hours from the previous dose), and at 
CCI
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repeated daily doses administered orally for 10 days of up to 500 mg PF-07321332 q12h with 
100 mg ritonavir q12h. 
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/ritonavir 300 mg/100 mg oral 
powder mixed with water compared to the 
PF-07321332/ritonavir commercial tablets under 
fasted conditions.
•
To estimate the rBA of the 
PF-07321332/ritonavir 300 mg/100 mg oral 
powder mixed with applesauce compared to the 
PF-07321332/ritonavir commercial tablets under 
fasted conditions.
•
To estimate the rBA of the 
PF-07321332/ritonavir 300 mg/100 mg oral 
powder mixed with vanilla pudding compared to 
the PF-07321332/ritonavir commercial tablets
under fasted conditions.
•
The ratio of AUClast, AUCinf (if data permits) 
and Cmax of PF-07321332 and ritonavir.
Secondary Objective: 
Secondary Endpoints: 
•
To evaluate the safety and tolerability of 
PF-07321332/ritonavir in healthy participants.
•
To assess the palatability of 
PF-07321332/ritonavir oral powder mixed with 
water/applesauce/vanilla pudding.
•
Assessment of TEAEs, clinical laboratory 
abnormalities, vital signs, PEs, and 12-lead 
ECGs.
•
Assessment of palatability using via 
questionnaire: mouth feel, bitterness, 
tongue/mouth burn, throat burn and overall 
liking.
 
 
 
 
 
 
 
 
 
 
 
 
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4. STUDY DESIGN
4.1. Overall Design
This is a Phase 1, open-label, single-dose, randomized, crossover study in healthy adult 
participants to estimate rBA of PF-07321332/ritonavir 300 mg/100 mg oral powder 
formulation mixed with 3 different delivery vehicles (Test formulations) compared to the
PF-07321332/ritonavir commercial tablet formulation (Reference formulation) under fasted
condition. The study will also assess the safety, tolerability, and palatability of 
PF-07321332/ritonavir oral powder in healthy adult participants.
Approximately 12 healthy male and/or female participants will be enrolled and randomized 
to 1 of 4 possible treatment sequences to ensure at least 10 participants will complete the 
study. Participants who discontinue from the study for nonsafety reasons may be replaced at 
the sponsor’s discretion in collaboration with the investigator. The replacement participant 
will receive the same treatment sequences as the participant who discontinued. 
Each enrolled participant will participate in 4 study periods to receive 4 different treatments 
according to the sequence determined by randomization: 

Treatment A: Single oral dose of PF-07321332/ritonavir 300 mg 
(2 × 150 mg)/100 mg commercial tablets under fasted conditions (Reference) 

Treatment B: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with water under fasted conditions (Test 1) 

Treatment C: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with applesauce under fasted conditions (Test 2) 

Treatment D: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with vanilla pudding under fasted conditions (Test 3)  
Participants will be randomly assigned to 1 of 4 sequences as shown below in Table 1.
Participants will be discharged on Day 4 of Period 4, 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 11 weeks.
Table 1.
Randomized Treatment Sequences
Treatment
Sequence
Period 1
Period 2
Period 3
Period 4
Sequence 1 (N =3)
Treatment A
Treatment B
Treatment C
Treatment D
Sequence 2 (N =3)
Treatment B
Treatment D
Treatment A
Treatment C
Sequence 3 (N =3)
Treatment C
Treatment A
Treatment D
Treatment B


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Table 1.
Randomized Treatment Sequences
Treatment
Sequence
Period 1
Period 2
Period 3
Period 4
Sequence 4 (N =3)
Treatment D
Treatment C
Treatment B
Treatment A
Healthy participants will be screened to determine eligibility within 28 days prior to study 
treatment. Medical history and results of PEs, vital signs, 12-lead ECGs, and clinical 
laboratory evaluations will determine eligibility. Eligible participants will be admitted to the 
PCRU on Day -1 and will be confined in the PCRU until discharge which is Day 4 of 
Period 4.
On Day 1 of each period, participants will receive a single dose of study intervention 
PF-07321332/ritonavir 300 mg/100 mg as per the randomization schedule. 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 PCRU on 
Period 4, 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 PCRU
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
PF-07321332/ritonavir oral powder is an alternative formulation for pediatric patients who 
are not able to swallow PF-07321332/ritonavir commercial tablets. The objective of the study 
is to estimate the rBA of PF-07321332/ritonavir oral powder mixed with 3 different delivery 
vehicles (Test formulations) compared to PF-07321332/ritonavir commercial tablet 
formulation (Reference formulation). The study will also assess the safety, tolerability, and 
palatability of PF-07321332/ritonavir oral powder in healthy adult participants.
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 and ritonavir concentrations prior to start of the next treatment, as 
PF-07321332 has a half-life of approximately 6 to13 hours when co-administered with 
ritonavir.
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).


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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/ritonavir 300 mg/100 mg BID for 5 days is the approved 
therapeutic dose and treatment duration under emergency use authorization. This dose is 
lower than the highest dose evaluated in the Phase 1 C4671001 study and is safe and well 
tolerated.
This study is designed to evaluate rBA of PF-07321332/ritonavir oral powder mixed with 3
different delivery vehicles compared to PF-07321332/ritonavir commercial tablet 
formulation in healthy adult participants at the approved therapeutic dose. Therefore, a single 
oral dose PF-07321332 /ritonavir 300/100 mg will be used in this relative bioavailability 
study. 
4.4. End of Study Definition
The end of the study is defined as the date of the 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 
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. Male and/or female participants must be ≥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.


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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 
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 


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situations related to COVID-19 pandemic (eg, contact with positive case) 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. Participants 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 the study confinement period.
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, old or age indeterminate 


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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;

TBili 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 
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. 


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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/ritonavir
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 PF-07321332/ritonavir dosing.

Dinner will be provided approximately 9 to 10 hours after PF-07321332/ritonavir 
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.

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 (or as specified 
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.


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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, PR, 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 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.
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.


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6.1. Study Intervention(s) Administered
PF-07321332 150 mg tablets and PF-07321332 oral powder will be supplied by the sponsor.
Commercially available ritonavir oral powder 100 mg will either be supplied by the sponsor 
or will be sourced by the PCRU.
Commercially available ritonavir 100 mg tablets will be sourced by the PCRU.
Vehicles (water, applesauce, vanilla pudding) for PF-07321332 and ritonavir oral powder 
administration will be sourced 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 tablets) with ritonavir 100 mg 
(as 1 × 100 mg tablet) with approximately 240 mL ambient temperature water or 
PF-07321332/ritonavir 300 mg/100 mg oral powder mixed with either water or applesauce or 
vanilla pudding with approximately 240 mL ambient temperature water administered orally
starting at approximately 0800 hours (plus or minus 2 hours). PF-07321332 and ritonavir will 
be dosed simultaneously (within no more than 5 minutes of each other). 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, PR, and ECG measurements), 
eating, and drinking beverages other than water during the first 4 hours after 
PF-07321332/ritonavir dosing.
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.


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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.
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 150 mg tablets will be prepared at the PCRU 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 PCRU into individual dosing containers using the package insert as 


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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/ritonavir oral powder will be prepared at the PCRU 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). Details of dose preparations, volume/amount of food 
vehicle, 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 PCRU 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 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 100 mg within a 
24-hour time period [±2 hours] will be considered an overdose.
There is no specific treatment for an overdose.


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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 
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.


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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;

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. 


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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.

Severe NSAE (eg, severe NSAEs considered at least possibly related to study drug 
administration) in 2 participants, independent of whether it is 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;


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
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.
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.


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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.
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.


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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
300 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 
Section 5.3 Lifestyle Considerations and Section 6.8 Concomitant Therapy of the Protocol.
8.1. Efficacy Assessments
Not applicable.
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 PE will include, at a minimum, assessments of general appearance, the respiratory 
and cardiovascular systems, and participant-reported symptoms.
PEs may be conducted by a physician, trained physician's assistant, or nurse practitioner as 
acceptable according to local regulation. 


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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. 
PE findings collected during the study will be considered source data and will not be required 
to be reported, unless otherwise noted. Any untoward PE 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 PR is acceptable; however, when done 
manually, PR 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 PR should be 
obtained prior to the nominal time of the blood collection.
Additional collection times, or changes to collection times, of BP and PR will be permitted, 
as necessary, to ensure appropriate collection of safety data.
8.2.2.1. 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 


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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.
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.


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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 PCRU 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.
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 


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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 
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.


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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.
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 
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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.

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 


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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. 
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.


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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.
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
Not applicable.
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.


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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.
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 and ritonavir 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. 


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Samples will be used to evaluate the PK of PF-07321332 and ritonavir.
 
 
 
Samples collected for measurement of plasma concentrations of PF-07321332 and ritonavir
will be analyzed using a validated analytical method in compliance with applicable SOPs.
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.
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.
 
 
 
 
 
 
 
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8.7. Immunogenicity Assessments
Immunogenicity assessments are not included in this study.
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8.8. Health Economics
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study.
8.9. Taste Assessment of PF-07321332 Suspension 
The sensory attributes of PF-07321332/ritonavir oral powder will be evaluated by the 
participant using a Taste Assessment Questionnaire (Appendix 8) in the period when 
suspension may be administered. Partcipants will review the taste questionnaire and 
instructions prior to the first taste assessment to Treatment B, C, D, on Period 1 Day 1. Each 
participant will complete the Taste Assessment Survey immediately following dosing 
(within 1 min) and at 5, 10, and 20 minutes post oral administration of PF-
07321332/ritonavir oral powder.
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.
PK Concentration Set
All participants who take at least 1 dose of study intervention 
and in whom at least 1 concentration value is reported.


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Participant Analysis 
Set
Description
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 and ritonavir 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 and Ritonavir 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 curve 
from time 0 to the time of the last measurable
concentration (Clast).
Linear/Log trapezoidal method.
Cmax
Maximum observed concentration
Observed directly from data
 
 
 
 
 
 
 
*If data permits.
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9.3.2. Statistical Methods for PK Data
For the primary objective, 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% confidence intervals will be obtained 
from the model. The adjusted mean differences and 90% confidence intervals for the 
differences will be exponentiated to provide estimates of the ratio of adjusted geometric 
means (Test/Reference) and 90% confidence intervals for the ratios. Treatment A will be the 
Reference treatment while Treatments B, C, and D will be the Test treatments.
 
 
 
 
PK parameters, including plasma AUCinf (if data permits), AUClast, Cmax, and
(if data 
permits) of PF-07321332 and ritonavir will be summarized descriptively by treatment. 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 and ritonavir 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 
reported, unless otherwise noted. However, any untoward findings identified on physical 
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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.
9.3.4. Other Analyse(s)
9.3.4.1. Taste Assessment
The data collected for taste assessment using the sponsor-provided taste questionnaire will be 
numerically derived by measuring length (using a scale with gradations of at least 0.1 cm) of 
the “x” marked by the participant relative to the “good trait”. The taste attributes (bitterness, 
and tongue/mouth burn sensation) from the taste questionnaires (Appendix 8) will be listed 
and descriptively summarized and appropriate plots may be generated.
 
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 will provide adequate precision to estimate the relative 
bioavailability and intrasubject variability PF-07321332. The following table presents the 
width of 90% CI for different estimated effects, with 80% coverage probability.
Parameter
Estimated Effect
(100*Test/Reference)
90% CI
CI Width
AUC
85%
75.19%
96.09%
20.90%
90%
79.61%
101.74%
22.13%
95%
84.04% 
107.39%
23.36%
100%
88.46% 
113.05%
24.59%
105%
92.88% 
118.7%
25.82%
110%
97.31% 
124.35%
27.05%
115%
101.73% 
130%
28.28%
Cmax
85%
78.47% 
92.08%
13.61%
90%
83.08% 
97.49%
14.41%
95%
87.7% 
102.91%
15.21%
100%
92.31% 
108.33%
16.01%
105%
96.93% 
113.74%
16.81%
110%
101.55% 
119.16%
17.61%
115%
106.16% 
124.57%
18.41%
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These estimates are based on the assumption that within-participant standard deviations 
are 0.161and 0.105 for lnCmax and lnAUCinf  , respectively, as obtained from clinical 
Studies C4671001 and C4671014 in healthy participants.
In addition, a sample size of 12 participants will provide adequate precision to estimate the 
relative bioavailability and intrasubject variability ritonavir. The following table presents the 
width of 90% CI for different estimated effects, with 80% coverage probability.
Parameter
Estimated Effect
(100*Test/Reference)
90% CI
CI Width
AUC
85%
71.18%
101.50%
30.32%
90%
75.37%
107.47%
32.10%
95%
79.56%
113.44%
33.89%
100%
83.74%
119.41%
35.67%
105%
87.93%
125.38%
37.45%
110%
92.12%
131.35%
39.24%
115%
96.30%
137.32%
41.02%
Cmax
85%
63.39%
113.99%
50.60%
90%
67.11%
120.69%
53.58%
95%
70.84%
127.40%
56.55%
100%
74.57%
134.10%
59.53%
105%
78.30%
140.81%
62.51%
110%
82.03%
147.51%
65.48%
115%
85.76%
154.22%
68.46%
These estimates are based on the assumption that within-participant standard deviations 
are 0.234 and 0.387 for lnAUCinf  and lnCmax, respectively, as obtained from clinical 
Study C4671014 in healthy participants.
Participants who withdraw from the study or discontinue treatment, or whose PK samples are 
considered to be nonevaluable 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. Financial Disclosure
Not applicable.
10.1.3. 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.


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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.
10.1.4. Data Protection
All parties will comply with all applicable laws, including laws regarding the implementation 
of organizational and technical measures to ensure protection of participant data.
Participants’ personal data will be stored at the study site in encrypted electronic and/or paper 
form and will be password-protected or secured in a locked room to ensure that only 
authorized study staff have access. The study site will implement appropriate technical and 
organizational measures to ensure that the personal data can be recovered in the event of 
disaster. In the event of a potential personal data breach, the study site will be responsible for 
determining whether a personal data breach has in fact occurred and, if so, providing breach 
notifications as required by law.
To protect the rights and freedoms of participants with regard to the processing of personal 
data, participants will be assigned a single, participant-specific numerical code. Any 
participant records or data sets that are transferred to the sponsor will contain the numerical 
code; participant names will not be transferred. All other identifiable data transferred to the 
sponsor will be identified by this single, participant-specific code. The study site will 
maintain a confidential list of participants who participated in the study, linking each 
participant’s numerical code to 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.
10.1.5. Committees Structure
10.1.5.1. Data Monitoring Committee 
This study will not use a DMC.
10.1.6. Dissemination of Clinical Study Data
Pfizer fulfills its commitment to publicly disclose clinical study results through posting the 
results of studies on www.clinicaltrials.gov (ClinicalTrials.gov), the EudraCT, 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, 


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regardless of the geographical location in which the study is conducted. These results are 
submitted for posting in accordance with the format and timelines set forth by US law.
EudraCT
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.
10.1.7. Data Quality Assurance
All participant data relating to the study will be recorded on printed or electronic CRF unless 
transmitted to the sponsor or designee electronically (eg, laboratory data). The investigator is 
responsible for verifying that data entries are accurate and correct by physically or 
electronically signing the CRF.


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Guidance on completion of CRFs will be provided in the CRF Completion Requirements 
document.
The investigator must ensure that the CRFs are securely stored at the study site in encrypted 
electronic 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.


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10.1.8. Source Documents
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected. Source documents are filed at the investigator site.
Data reported on the CRF or entered in the eCRF that are from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
investigator may need to request previous medical records or transfer records, depending on 
the study. Also, current medical records must be available.
Definition of what constitutes source data and its origin can be found the Source Document 
Locator, which is maintained by the the sponsor’s designee (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.
10.1.9. 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.


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Reasons for the early closure of a study site by the sponsor may include but are not limited 
to:

Failure of the investigator to comply with the protocol, the requirements of the 
IRB/EC or local health authorities, the sponsor's procedures, or the ICH GCP 
guidelines;

Inadequate recruitment of participants by the investigator;

Discontinuation of further study intervention development.
If the study is prematurely terminated or suspended, the sponsor shall promptly inform the 
investigators, the ECs/IRBs, the regulatory authorities, and any CRO(s) used in the study of 
the reason for termination or suspension, as specified by the applicable regulatory 
requirements. The investigator shall promptly inform the participant and should assure 
appropriate participant therapy and/or follow-up.
Study termination is also provided for in the clinical study agreement. If there is any conflict 
between the contract and this protocol, the contract will control as to termination rights.
10.1.10. Publication Policy
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. 


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If publication is addressed in the clinical study agreement, the publication policy set out in 
this section will not apply.
10.1.11. 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 
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 and/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.
 
 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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Final Protocol 09 February 2022
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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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Final Protocol 09 February 2022
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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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Protocol C4671024
Final Protocol 09 February 2022
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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 injury but adapt 
are termed “adaptors.” In some participants, transaminase elevations are a harbinger of a 
more serious potential outcome. These participants fail to adapt and therefore are 
“susceptible” to progressive and serious liver injury. Participants who experience a 
transaminase elevation above 3 × ULN should be monitored more frequently to determine if 
they are “adaptors” or are “susceptible.”
In the majority of DILI cases, elevations in AST and/or ALT may precede TBili elevations 
(>2 × ULN) by several days or weeks. Any substantial elevaton in ALT, AST or bilirubin
above baseline may be a potential DILI. The treating physician can determine what is an 
elevation of concern—in many cases, elevation in ALT, AST 3 × ULN or TBili value
1.5 × ULN prompts treating physicians to consider evaluation for hepatic injury. Hepatic 
injury may be from the study druy, a co-administerd study drug or the disease under study or 
other medical conditions.
The threshold of laboratory abnormalities for causality assessment and a potential DILI case 
depends on the participant’s individual baseline values and underlying conditions based on 
treating physicians’ opinion and declared attribution. Participants who present with the 
following laboratory abnormalities should be evaluated further 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 ≥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 by the treating physician and their health care team; 


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Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 78
any case where uncertainty remains as to whether it represents a potential DILI and also 
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.
In addition to repeating measurements of AST and ALT and TBili for suspected Hy’s law 
cases, additional laboratory tests should include albumin, CK, direct and indirect bilirubin, 
GGT, PT/INR, total bile acids, and alkaline phosphatase. Consideration should also be given 
to drawing a separate tube of clotted blood and an anticoagulated tube of blood for further 
testing, as needed, for further contemporaneous analyses at the time of the recognized initial 
abnormalities to determine etiology. A detailed history, including relevant information, such 
as review of ethanol, acetaminophen/paracetamol (either by itself or as a coformulated 
product in prescription or over-the-counter medications), recreational drug, or supplement 
(herbal) use and consumption, family history, sexual history, travel history, history of contact 
with a jaundiced person, surgery, blood transfusion, history of liver or allergic disease, and 
potential occupational exposure to chemicals, should be collected at time and dose of last 
dose of study intervention. 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 (Hy’s law) cases if no 
other reason for the LT abnormalities has yet been found. The treating physician is 
encouraged to consult with any other speciality that may assit in interprepation of the lab 
result or patient care management (eg, gastroenterologist, clinical pathologist, pharmacy, 
etc). 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 LT 
abnormalities.
A potential DILI or potential Hy’s law case becomes a potentially confirmed case only after 
all results of reasonable investigations have been received and have excluded an alternative 
etiology.


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Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 79
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).


PF-07321332 
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Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
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
Ventricular rhythms >30 seconds’ duration, including idioventricular rhythm 
(heart rate <40 bpm), accelerated idioventricular rhythm (HR >40 bpm to
<100 bpm), and monomorphic/polymorphic ventricular tachycardia 
(HR >100 bpm (such as torsades de pointes)).

Type II second-degree (Mobitz II) AV block.

Complete (third-degree) heart block.
ECG Findings That Qualify as SAEs

Change in pattern suggestive of new myocardial infarction.

Sustained ventricular tachyarrhythmias (>30 seconds’ duration).

Second- or third-degree AV block requiring pacemaker placement.

Asystolic pauses requiring pacemaker placement.

Atrial flutter or fibrillation with rapid ventricular response requiring 
cardioversion.

Ventricular fibrillation/flutter.

At the discretion of the investigator, any arrhythmia classified as an adverse 
experience.
The enumerated list of major events of potential clinical concern are recommended as “alerts” or 
notifications from the core ECG laboratory to the investigator and Pfizer study team, and not to be 
considered as all inclusive of what to be reported as AEs/SAEs.


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Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 81
10.8. Appendix 8: Palatability Questionnaire
PF-07321332/Ritonavir Oral Powder Palatability Questionnaire
1. Questionnaire should be administered to adult subjects, preferably by the clinician or 
the nurse.
2. Use colored copy of the Palatability Questionnaire.
3. Do not alter (reduce or enlarge) the original size of the Palatability
Questionnaire.
4. Please collect the following background information:
Background Information
Study #/Study Site
Period and Day
Subject ID (Rand ID)
Treatment
Collect Date
Questionnaire Fully Completed (circle one)
Yes/No


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Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 82
Please answer the following questions and provide a mark () on the color bar at 
1 (immediately), 5, 10 and 20 minutes after dosing. Please ensure subject has access to 
these descriptions when completing the questionnaire. 
Q1: Mouth feel – Please tell us about the mouth feel (such as grittiness, stickiness, 
waxiness) of the product you tasted.
Q2: Bitterness – Please tell us about the degree of bitterness of the product you tasted.
Q3: Tongue/mouth burn – Please tell us about the degree of tongue/mouth burn of the 
product you tasted.
Q4: Throat burn – Please tell us about the degree of throat burn of the product you 
tasted.
Q5: Overall liking – Please indicate how much you like or dislike the product you 
tasted.


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 83
Example: How to provide a mark () on the color bar.

Good (score = 0)
Bad (score = 100)


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Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 84
Within 1 minute (immediately) after dosing
Provide a mark ( ) on the color bar.
Mouth Feel
Bitterness
Tongue/Mouth 
Burn
Throat Burn
Overall Liking
Good
Bad


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 85
5 minutes after dosing
Provide a mark ( ) on the color bar.
Mouth Feel
Bitterness
Tongue/Mouth 
Burn
Throat Burn
Overall Liking
Bad
Good


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 86
10 minutes after dosing
Provide a mark ( ) on the color bar.
Mouth Feel
Bitterness
Tongue/Mouth 
Burn
Throat Burn
Overall Liking
Good
Bad


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 87
20 minutes after dosing
Provide a mark ( ) on the color bar.
Mouth Feel
Bitterness
Tongue/Mouth 
Burn
Throat Burn
Overall Liking
Good
Bad


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 88
Additional Feedback – After completing the “20 minute after dosing” palatability questions,
please provide any additional descriptive feedback in the box below regarding the taste or 
odor of the drug.


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 89
10.9. Appendix 9: 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
ALT
alanine aminotransferase
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
β-hCG
β‑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
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
CCI
CCI


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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
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 Union Drug Regulating Authorities Clinical Trials (European 
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
HR
heart rate
HRT
hormone replacement therapy
IB
Investigator’s Brochure
ICD
informed consent document
ICH
International Council for Harmonisation for Techinical Requirements for 
Pharmaceuticals for Human Use
ID
identification
lnAUCinf
log-transformed AUCinf
lnCmax
log-transformed Cmax
IND
Investigational New Drug 
IPAL
Investigational Product Accountability Log
IQMP
Integrated Quality Management Plan


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 91
Abbreviation
Term
IRB
Institutional Review Board
IV
Intravenous(ly)
Kel
first order elimination rate constant
Ki
inhibition constant
LBBB
left bundle branch block
LFT
liver function test
lnAUCinf
log-transformed AUCinf
lnCmax
log-transformed Cmax
Loge
natural logarithm
LFT
liver function test
MAD
multiple ascending dose
MCH
mean corpuscular hemoglobin
MCHC
mean corpuscular hemoglobin concentration
MCV
mean corpuscular volume
Mpro
main protease
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
pharmacodynamic(s)
PE
physical examination 
PK
pharmacokinetic(s)
PR
pulse rate
PT-INR
prothrombin time-international normalized ratio
q12h
every 12 hours
QTc
corrected QT interval
QTcF
QT corrected using Fridericia’s formula
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
SE
supratherapeutic exposure
SoA
schedule of activities
SOC
System Organ Class


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Abbreviation
Term
SOP
standard operating procedure
SRSD
single reference safety document
SUSAR
Suspected Unexpected Serious Adverse Reaction
TBili
total bilirubin
TEAE
treatment-emergent adverse event
THC
tetrahydrocannabinol
ULN
upper limit of normal
US
United States
WBC
white blood cell
WHO
World Health Organization
WOCBP
woman/women of childbearing potential
CCI
CCI
CCI


PF-07321332 
Protocol C4671024
Final Protocol 09 February 2022
PFIZER CONFIDENTIAL
Page 93
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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PPD

SAP_001.pdf: 
Protocol C4671024 (PF-07321332) Statistical Analysis Plan
Page 1 of 17
PFIZER CONFIDENTIAL
Protocol C4671024
A PHASE 1, OPEN-LABEL, RANDOMIZED, SINGLE DOSE, 
CROSSOVER STUDY TO ESTIMATE THE RELATIVE 
BIOAVAILABILITY OF PF-07321332/RITONAVIR ORAL POWDER IN 
3 DIFFERENT DELIVERY VEHICLES RELATIVE TO THE 
COMMERCIAL PF-07321332/RITONAVIR TABLETS IN HEALTHY 
ADULT PARTICIPANTS UNDER FASTED CONDITIONS.
Statistical Analysis Plan 
(SAP)
Version:
1.0
SAP Author: 
 
Mumbai)
Date:
05-APR-2022
PPD


Protocol C4671024 (PF-07321332) Statistical Analysis Plan
Page 2 of 17
PFIZER CONFIDENTIAL
Revision History
Version
Date
Author(s)
Summary of Changes/Comments
1.0
April 05, 2022
Not Applicable
NOTE: Italicized text within this document has been taken verbatim from the Protocol.
PPD


Protocol C4671024 (PF-07321332) Statistical Analysis Plan
Page 3 of 17
PFIZER CONFIDENTIAL
TABLE OF CONTENTS 
LIST OF TABLES.....................................................................................................................4
LIST OF FIGURES ...................................................................................................................4
APPENDICES ...........................................................................................................................4
1. AMENDMENTS FROM PREVIOUS VERSION(S) ...........................................................5
2. INTRODUCTION .................................................................................................................5
2.1. Study Design .............................................................................................................5
2.2. Study Objectives .......................................................................................................6
2.2.1. Primary Objectives .......................................................................................6
2.2.2. Secondary Objective.....................................................................................7
3. INTERIM ANALYSES, FINAL ANALYSES AND UNBLINDING..................................7
4. HYPOTHESES AND DECISION RULES...........................................................................7
4.1. Statistical Hypotheses ...............................................................................................7
4.2. Statistical Decision Rules..........................................................................................7
5. ANALYSIS SETS .................................................................................................................8
5.1. Enrolled/Randomly Assigned to Study Intervention ................................................8
5.2. Pharmacokinetic (PK) Analysis Set ..........................................................................8
5.2.1. Concentration Analysis Set...........................................................................8
5.2.2. Parameter Analysis Set.................................................................................8
5.3. Pharmacodynamic Analysis Set................................................................................8
5.4. Safety Analysis Set....................................................................................................8
5.5. Other Analysis Sets ...................................................................................................8
5.6. Treatment Misallocations..........................................................................................8
5.7. Protocol Deviations...................................................................................................8
5.7.1. Deviations Assessed Prior to Randomization...............................................9
5.7.2. Deviations Assessed Post-Randomization....................................................9
6. ENDPOINTS AND COVARIATES .....................................................................................9
6.1. Efficacy Endpoint(s) .................................................................................................9
6.2. Safety Endpoints .......................................................................................................9
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Protocol C4671024 (PF-07321332) Statistical Analysis Plan
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PFIZER CONFIDENTIAL
6.4. Covariates................................................................................................................10
7. HANDLING OF MISSING VALUES ................................................................................10
7.1. Concentrations Below the Limit of Quantification.................................................10
7.2. Deviations, Missing Concentrations and Anomalous Values .................................10
7.3. Pharmacokinetic Parameters ...................................................................................11
8. STATISTICAL METHODOLOGY AND STATISTICAL ANALYSES ..........................11
8.1. Statistical Methods ..................................................................................................11
8.2. Statistical Analyses .................................................................................................11
8.3. Safety Analysis........................................................................................................14
8.3.1. Treatment and Disposition of Participants .................................................14
8.3.2. Demographic and Clinical Examination Data............................................14
8.3.3. Discontinuation(s).......................................................................................14
8.3.4. Adverse Events ...........................................................................................14
8.3.5. Laboratory Data..........................................................................................15
8.3.6. Vital Signs Data..........................................................................................15
8.3.7. ECG Data....................................................................................................15
8.3.8. Other Safety Data .......................................................................................15
8.3.9. Concomitant Treatments.............................................................................15
8.3.10. Screening and Other Special Purpose Data ..............................................15
9. REFERENCES ....................................................................................................................16
10. APPENDICES ...................................................................................................................17
LIST OF TABLES
Table 1.
Study Schematics........................................................................................6
Table 3.
PK Parameters to be Summarized Descriptively by Treatment ...............12
LIST OF FIGURES
None
APPENDICES
Appendix 1. SAS CODE FOR ANALYSES...........................................................................17
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PFIZER CONFIDENTIAL
1. AMENDMENTS FROM PREVIOUS VERSION(S) 
None.
2. INTRODUCTION
PF-07321332 is a potent and selective inhibitor of the SARS-CoV-2 Mpro 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 efficacious. 
The purpose of this study is to estimate the rBA of PF-07321332/ritonavir oral powder 
relative to the commercial tablet formulation under fasted condition in healthy adult 
participants. The study will also assess the effect of 3 different food vehicles on the rBA of the 
PF-07321332/ritonavir oral powder formulation as well as the safety, tolerability, and 
palatability of PF-07321332/ritonavir oral powder in healthy adult participants.
This study objective is to estimate the rBA of PF-07321332/ritonavir oral powder mixed with 
3 different delivery vehicles (Test formulations) compared to PF-07321332/ritonavir 
commercial tablet formulation (Reference formulation).
2.1. Study Design
This is a Phase 1, open label, single dose, randomized, crossover study in healthy adult 
participants to estimate rBA of PF-07321332/ritonavir 300 mg/100 mg oral powder mixed 
with 3 different delivery vehicles (Test formulations) compared to the PF-07321332/ritonavir 
commercial tablets (Reference formulation) under fasted conditions. The study will also 
assess the safety, tolerability, and palatability of PF-07321332/ritonavir oral powder in 
healthy adult participants.
The study will consist of 4 treatments: a single oral dose of PF-07321332/ritonavir 
300 (2 × 150 mg)/100 mg tablets (Treatment A), a single oral dose of PF-07321332/ritonavir 
300 mg/100 mg oral powder mixed in water (Treatment B), a single oral dose of 
PF-07321332/ritonavir 300 mg/100 mg oral powder mixed in applesauce (Treatment C) and 
a single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder mixed in vanilla 
pudding (Treatment D). All treatments will be administered under fasted conditions.
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. On Day 1 of each period, 
participants will receive a single dose of study intervention PF-07321332/ritonavir 
300 mg/100 mg as per the randomization schedule.


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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 PCRU
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.
Participants will be randomly assigned to 1 of 4 sequences as shown below in Table 1.
Participants will be discharged on Day 4 of Period 4, 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.
Table 1.
Study Schematics
Sequence
Period 1
Period 2
Period 3
Period 4
1
(3 participants)
Treatment A
Treatment B
Treatment C
Treatment D
2
(3 participants)
Treatment B
Treatment D
Treatment A
Treatment C
3
(3 participants)
Treatment C
Treatment A
Treatment D
Treatment B
4
(3 participants)
Treatment D
Treatment C
Treatment B
Treatment A

Treatment A: Single oral dose of PF-07321332/ritonavir 
300 mg (2 × 150 mg)/100 mg commercial tablets under fasted conditions (Reference).

Treatment B: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with water under fasted conditions (Test 1).

Treatment C: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with applesauce under fasted conditions (Test 2).

Treatment D: Single oral dose of PF-07321332/ritonavir 300 mg/100 mg oral powder 
mixed with vanilla pudding under fasted conditions (Test 3).
2.2. Study Objectives
2.2.1. Primary Objectives

To estimate the rBA of the PF-07321332/ritonavir 300 mg/100 mg oral powder mixed 
with water compared to the PF-07321332/ritonavir commercial tablets under fasted 
conditions.


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•
To estimate the rBA of the PF-07321332/ritonavir 300 mg/100 mg oral powder mixed 
with applesauce compared to the PF-07321332/ritonavir commercial tablets under 
fasted conditions.
•
To estimate the rBA of the PF-07321332/ritonavir 300 mg/100 mg oral powder mixed 
with vanilla pudding compared to the PF-07321332/ritonavir commercial tablets 
under fasted conditions.
2.2.2. Secondary Objective
•
To evaluate the safety and tolerability of PF-07321332/ritonavir in healthy 
participants.
•
To assess the palatability of PF-07321332/ritonavir oral powder mixed with 
water/applesauce/vanilla pudding.
 
 
 
3. INTERIM ANALYSES, FINAL ANALYSES AND UNBLINDING
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.
Final analysis will follow the official database release. As this will be an open-label study, 
there is no formal unblinding of the randomization code.
4. HYPOTHESES AND DECISION RULES
4.1. Statistical Hypotheses
No hypotheses are required.
4.2. Statistical Decision Rules
No decision rules are required.
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5. ANALYSIS SETS
5.1. 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.
5.2. Pharmacokinetic (PK) Analysis Set
5.2.1. Concentration Analysis Set
All participants who take at least 1 dose of study intervention and in whom at least 
1 concentration value is reported.
5.2.2. Parameter Analysis 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.
5.3. Pharmacodynamic Analysis Set
None.
5.4. 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.
5.5. Other Analysis Sets
None.
5.6. Treatment Misallocations 
All analyses will be performed on an “as-treated” basis and will not include data from 
participants who are randomized but not treated.
If a participant takes a treatment that is not consistent with the treatment they are randomized 
to, for example takes a treatment out of sequence or takes the same treatment twice, then they 
will be reported under the treatment that they actually receive for all safety, and PK analyses, 
where applicable.
5.7. Protocol Deviations
Participants who experience events that may affect their PK profile (eg lack of compliance 
with dosing) may be excluded from the PK analysis. At the discretion of the 
pharmacokineticist a concentration value may also be excluded if the deviation in sampling 
time is of sufficient concern or if the concentration is anomalous for any other reason.


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A full list of protocol deviations will be compiled and reviewed to identify major and minor 
deviations prior to database closure.
5.7.1. Deviations Assessed Prior to Randomization
At Screening, the investigator will assess participants against the inclusion and exclusion 
criteria as set out in Sections 5.1 and 5.2 of the protocol.
5.7.2. Deviations Assessed Post-Randomization
A full list of protocol deviations for the study report will be compiled prior to database 
closure. Any significant deviation from the protocol will be reviewed prior to database 
closure and a decision taken regarding evaluation for each analysis population.
6. ENDPOINTS AND COVARIATES
6.1. Efficacy Endpoint(s)
None.
6.2. Safety Endpoints
An adverse event will be considered a Treatment-Emergent Adverse Event (TEAE) if the 
event started during the effective duration of treatment. All events that start on or after the 
first dosing day and time/start time, if collected, but before the last dose plus the lag time 
(28 days) will be flagged as TEAEs. The algorithm will not consider any events that started 
prior to the first dose date. 
Events that occur in a non-treatment period (for example, Washout or Follow-up) will be 
counted as treatment emergent and attributed to the previous treatment taken.
The following data are considered in standard safety analyses (see protocol for collection 
days and list of parameters):
•
adverse events,
•
laboratory data.
6.3. Other Endpoints
 
 
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6.3.2. PD Endpoints
None.
6.4. Covariates
None.
7. HANDLING OF MISSING VALUES
For the analysis of safety endpoints, the sponsor data standard rules for imputation will be 
applied.
7.1. Concentrations Below the Limit of Quantification
In all data presentations (except listings), concentrations below the limit of quantification 
(BLQ) will be set to zero. (In listings BLQ values will be reported as “<LLQ”, where LLQ 
will be replaced with the value for the lower limit of quantification).
7.2. Deviations, Missing Concentrations and Anomalous Values
In summary tables and plots of median profiles, statistics will be calculated having set 
concentrations to missing if 1 of the following cases is true:
1. A concentration has been collected as ND (ie not done) or NS (ie no sample).
2. A deviation in sampling time is of sufficient concern or a concentration has been 
flagged anomalous by the pharmacokineticist.
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Note that summary statistics will not be presented at a particular time point if more than 
50% of the data are missing.
7.3. Pharmacokinetic Parameters
Actual PK sampling times will be used in the derivation of PK parameters. In situation of 
missing actual PK sampling time, nominal time may be used, when appropriate.
If a PK parameter cannot be derived from a participant’s concentration data, the parameter 
will be coded as NC (ie, not calculated). (Note that NC values will not be generated beyond 
the day that a participant discontinues).
In summary tables, statistics will be calculated by setting NC values to missing; and statistics 
will be presented for a particular treatment with ≥3 evaluable measurements. For statistical 
analyses (ie, analysis of variance), PK parameters coded as NC will also be set to missing; 
and analyses will not be performed for a particular parameter if more than 50% of the data 
are NC.
If an individual participant has a known biased estimate of a PK parameter (due for example 
to an unexpected event such as vomiting before all the compound is adequately absorbed in 
the body), this will be footnoted in summary tables and will not be included in the calculation 
of summary statistics or statistical analyses.
8. STATISTICAL METHODOLOGY AND STATISTICAL ANALYSES
8.1. Statistical Methods
Precision of the estimate of PK parameters will be determined by constructing 
90% confidence intervals around the estimated difference between the Test and Reference 
treatments using a mixed effects model based on natural log transformed data. The mixed 
effects model will be implemented using SAS Proc Mixed, with REML estimation method 
and Kenward-Roger degrees of freedom algorithm.
8.2. Statistical Analyses
Natural log transformed AUCinf (if data permits), AUClast and Cmax of PF-07321332 and 
ritonavir 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% confidence intervals will be 
obtained from the model. The adjusted mean differences and 90% confidence intervals for 
the differences will be exponentiated to provide estimates of the ratio of adjusted geometric 
means (Test/Reference) and 90% confidence intervals for the ratios. Treatment A will be the 
Reference treatment while Treatments B, C, and D will be the Test treatments.


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PK parameters for PF-07321332 and ritonavir, including plasma AUCinf (if data permits), 
AUClast, Cmax, and Tmax,
 will be summarized
descriptively by treatment and analyte. 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 and analyte.
The plasma concentrations of PF-07321332 and ritonavir will be listed and descriptively 
summarized by nominal PK sampling time, treatment and analyte. Individual participant, as 
well as mean and median profiles of the plasma concentration time data will be plotted by 
treatment for each analyte 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.
Residuals from the model will be examined for normality and the presence of outliers via 
visual inspection of plots of residuals vs predicted values and normal probability plots of 
residuals but these will not be included in the clinical study report. If there are major 
deviations from normality or outliers then the effect of these on the conclusions will be 
investigated through alternative transformations and/or analyses excluding outliers. 
Justification for any alternative to the planned analysis will be given in the report of the 
study.
Table 3.
PK Parameters to be Summarized Descriptively by Treatment
Parameter
Summary Statistics
AUCinf, AUClast, 
Cmax, 
N, arithmetic mean, median, cv%, standard deviation, minimum, 
maximum, geometric mean and geometric cv%.
For AUCinf, AUClast and Cmax a listing of the individual participant ratios (Test/Reference) 
will be provided. 
Supporting data from the estimation of 
and AUCinf will be listed by treatment and analyte: 
terminal phase rate constant (kel); goodness of fit statistic from the log-linear regression (r2); 
the percent of AUCinf based on extrapolation (AUCextrap%); and the first, last, and number of 
time points used in the estimation of kel. This data may be included in the clinical study 
report.
Presentations for PF-07321332 and ritonavir concentrations will include:
•
A listing of all concentrations sorted by participant ID, period, treatment and nominal 
time postdose for each analyte. The concentration listing will also include the actual 
times. Deviations from the nominal time will be given in a separate listing.
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
A summary of concentrations by treatment and nominal time postdose for each 
analyte, where the set of statistics will include n, mean, median, standard deviation, 
coefficient of variation (cv), minimum, maximum and the number of concentrations 
above the lower limit of quantification.

Median concentrations time plots (on both linear and semi-log scales) against 
nominal time postdose by treatment (all treatments on the same plot per scale, based 
on the summary of concentrations by treatment and time postdose).

Mean concentrations time plots (on both linear and semi-log scales) against nominal 
time postdose by treatment (all treatments on the same plot per scale, based on the 
summary of concentrations by treatment and time postdose).

Individual concentration time plots by treatment (on both linear and semi-log scales) 
against actual time postdose (there will be separate spaghetti plots for each treatment 
per scale).

Individual concentration time plots by participant (on both linear and semi-log scales) 
against actual time postdose [there will be separate plots for each participant
(containing all treatments) per scale].
For summary statistics, median and mean plots by sampling time, the nominal PK sampling 
time will be used, for individual participant plots by time, the actual PK sampling time will 
be used.
In addition, the following presentations will be included to explore PK of PF-07321332 and 
ritonavir by Tasso® microsampling device:

Listings of AUC12, Cmax, and Tmax adjusted for blood/plasma ratio along with 
summary statistics.

Listings and summary of blood/plasma ratio.

Listings of AUC12, Cmax, and Tmax along with summary stat for paired (time matched) 
venous samples.

A listing of all concentrations sorted by participant ID, period and nominal time 
postdose.

A summary of concentrations by treatment and nominal time postdose, where the set 
of statistics will include n, mean, median, standard deviation, coefficient of variation 
(cv), minimum, maximum and the number of concentrations above the lower limit of 
quantification.


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
Median concentrations time plots (on both linear and semi-log scales) against 
nominal time postdose by treatment (all treatments on the same plot per scale, based 
on the summary of concentrations by treatment and time postdose).

Mean concentrations time plots (on both linear and semi-log scales) against nominal 
time postdose by treatment (all treatments on the same plot per scale, based on the 
summary of concentrations by treatment and time postdose).

Individual concentration time plots by treatment (on both linear and semi-log scales) 
against actual time postdose (there will be separate spaghetti plots for each treatment 
per scale).

Individual concentration time plots by participant (on both linear and semi-log scales) 
against actual time postdose [there will be separate plots for each participant 
(containing all treatments) per scale.
8.3. Safety Analysis
A set of summary tables split by treatment will be produced to evaluate any potential risk 
associated with the safety and toleration of administering study treatments.
8.3.1. Treatment and Disposition of Participants
Participant evaluation groups will show end of study participant disposition and will show 
which participants were analyzed for pharmacokinetics, as well as for safety (adverse events 
and laboratory data). Frequency counts will be supplied for participant discontinuation(s) by 
treatment.
Data will be reported in accordance with the sponsor reporting standards.
8.3.2. Demographic and Clinical Examination Data
A break down of demographic data will be provided for age, race, weight, body mass index, 
and height. Each will be summarized by sex at birth and ‘All Participants’ in accordance with 
the sponsor reporting standards.
8.3.3. Discontinuation(s)
Participant discontinuations, temporary discontinuations or dose reductions due to adverse 
events will be detailed and summarized by treatment.
Data will be reported in accordance with the sponsor reporting standards.
8.3.4. Adverse Events
Adverse events will be reported in accordance with the sponsor reporting standards by 
treatment.


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8.3.5. Laboratory Data
Laboratory data will be listed in accordance with the sponsor reporting standards.
8.3.6. Vital Signs Data
Vital signs data will be databased and available upon request.
8.3.7. ECG Data
ECG data will be databased and available upon request.
8.3.8. Other Safety Data
None.
8.3.9. Concomitant Treatments
All concomitant medication(s) as well as non-drug treatment(s) will be provided in the 
listings.
8.3.10. Screening and Other Special Purpose Data
If these data will be brought in-house, then it will be listed.


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9. REFERENCES
None.


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10. APPENDICES
Appendix 1. SAS CODE FOR ANALYSES
An example of the PROC MIXED code is provided below:
proc mixed data=tab.pk;
class seq period trt participant;
model l&var=seq period trt/ ddfm=KR;
random participant(seq) /participant=participant(seq);
lsmeans trt;
estimate 'B vs A' trt -1  1  0  0 /cl alpha=0.1;
estimate 'C vs A' trt -1  0  1  0 /cl alpha=0.1;
estimate 'D vs A' trt -1  0  0  1 /cl alpha=0.1;
ods 'Estimates' out=est&var;
ods 'lsmeans' out=ls&var;
ods 'covparms' out=cov&var;
ods 'tests3' out=tst&var;
run;
/* Letter assignments for treatments (trt) within the estimate statement above are as follows;
A: Nirmatrelvir/ritonavir 300 mg/100 mg commercial tablets (Reference)
B: Nirmatrelvir/ritonavir 300 mg/100 mg oral powder mixed with water (Test)
C: Nirmatrelvir/ritonavir 300 mg/100 mg oral powder mixed with applesauce (Test)
D: Nirmatrelvir/ritonavir 300 mg/100 mg oral powder mixed with vanilla pudding (Test)
*/;