A PHASE 1, RANDOMIZED, DOUBLE-BLIND, SPONSOR-OPEN, PLACEBO-CONTROLLED, FIRST-IN-HUMAN STUDY TO EVALUATE THE SAFETY, TOLERABILITY, AND PHARMACOKINETICS OF SINGLE ASCENDING ORAL DOSES OF PF-07258669 ADMINISTERED TO HEALTHY ADULT PARTICIPANTS
Phase: PHASE1
Conditions: Healthy Participants
Sponsor: Pfizer

PF-07258669
Protocol C4541001
Final Protocol Amendment 1, 09 November 2020
PFIZER CONFIDENTIAL
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A PHASE 1, RANDOMIZED, DOUBLE-BLIND, SPONSOR-OPEN, 
PLACEBO-CONTROLLED, FIRST-IN-HUMAN STUDY TO EVALUATE THE 
SAFETY, TOLERABILITY, AND PHARMACOKINETICS OF SINGLE 
ASCENDING ORAL DOSES OF PF-07258669 ADMINISTERED TO HEALTHY 
ADULT PARTICIPANTS
Study Intervention Number:
PF-07258669
Study Intervention Name:
N/A
US IND Number:
EudraCT Number:
2020-004280-42
Protocol Number:
C4541001
Phase:
1
Short Title: A Phase 1 Study of Single Ascending Doses of PF-07258669 in Healthy 
Adult 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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Protocol Amendment Summary of Changes Table
Document History
Document
Version Date
Summary and Rationale for Changes
Amendment 1
09 November 2020
•
Precautionary sentinel dosing will be 
used in each period of each cohort. The 
rationale for, and description of, 
sentinel dosing was added to 
Section 1.1 (Synopsis), Section 1.2 
(Schema), Section 1.3 (Schedule of 
Activities), Section 2.3 (Benefit/Risk 
Assessment), Section 2.3.1 (Risk 
Assessment), Section 4.1 (Overall 
Design), Section 4.2 (Scientific
Rationale for Study Design), and 
Section 6.6.1 (Dose Escalation and 
Stopping Rules).
•
The starting dose level for this study 
was reduced from 0.3 mg to 0.1 mg 
 
 
 
 
•
 
 
 
 
 
 
Original protocol
07 October 2020
N/A
This amendment incorporates all revisions to date, including amendments made at the
request of country health authorities and IRBs/ECs.
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TABLE OF CONTENTS
LIST OF TABLES.....................................................................................................................8
1. PROTOCOL SUMMARY.....................................................................................................9
1.1. Synopsis ....................................................................................................................9
1.2. Schema ....................................................................................................................11
1.3. Schedule of Activities .............................................................................................12
2. INTRODUCTION ...............................................................................................................15
2.1. Study Rationale .......................................................................................................15
2.2. Background .............................................................................................................15
2.2.1. MC4R and 
....................................................................15
2.2.5. Nonclinical Safety ......................................................................................17
2.3. Benefit/Risk Assessment.........................................................................................17
2.3.2. Benefit Assessment.....................................................................................21
2.3.3. Overall Benefit/Risk Conclusion................................................................21
3. OBJECTIVES AND ENDPOINTS.....................................................................................21
4. STUDY DESIGN.................................................................................................................22
4.1. Overall Design.........................................................................................................22
4.2. Scientific Rationale for Study Design.....................................................................22
4.3. Justification for Dose ..............................................................................................25
4.3.2. Human Exposure Stopping Limits..............................................................25
4.3.3. Rationale for Dose Selection ......................................................................26
4.4. End of Study Definition ..........................................................................................27
5. STUDY POPULATION......................................................................................................27
5.1. Inclusion Criteria.....................................................................................................28
5.2. Exclusion Criteria....................................................................................................28
5.3. Lifestyle Considerations..........................................................................................31
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5.3.1. Meals and Dietary Restrictions...................................................................31
5.3.2. Caffeine, Alcohol, and Tobacco .................................................................31
5.3.3. Activity .......................................................................................................31
5.3.4. Contraception..............................................................................................32
5.4. Screen Failures ........................................................................................................32
6. STUDY INTERVENTION..................................................................................................33
6.1. Study Intervention(s) Administered........................................................................33
6.1.1. Administration............................................................................................33
6.2. Preparation/Handling/Storage/Accountability ........................................................33
6.2.1. Preparation and Dispensing........................................................................34
6.3. Measures to Minimize Bias: Randomization and Blinding.....................................35
6.3.1. Allocation to Study Intervention ................................................................35
6.3.2. Breaking the Blind......................................................................................35
6.4. Study Intervention Compliance...............................................................................35
6.5. Concomitant Therapy..............................................................................................36
6.5.1. Rescue Medicine.........................................................................................36
6.6. Dose Modification...................................................................................................36
6.6.1. Dose Escalation and Stopping Rules ..........................................................36
6.7. Intervention After the End of the Study..................................................................38
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL...........................................................................38
7.1. Discontinuation of Study Intervention ....................................................................38
7.2. Participant Discontinuation/Withdrawal From the Study.......................................39
7.2.1. Withdrawal of Consent...............................................................................40
7.3. Lost to Follow-up....................................................................................................40
8. STUDY ASSESSMENTS AND PROCEDURES...............................................................41
8.1. Efficacy Assessments..............................................................................................42
8.2. Safety Assessments .................................................................................................42
8.2.1. Physical Examinations................................................................................42
8.2.2. Neurological Examinations ........................................................................43
8.2.3. Vital Signs ..................................................................................................43
8.2.4. Respiratory Rate .........................................................................................44

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8.2.5. Oral Body Temperature ..............................................................................44
8.2.6. Electrocardiograms.....................................................................................44
8.2.6.1. Continuous Cardiac Monitoring by Telemetry .........................45
8.2.7. Clinical Safety Laboratory Assessments ....................................................45
8.2.8. COVID-19 Specific Assessments...............................................................46
8.3. Adverse Events and Serious Adverse Events..........................................................46
8.3.1. Time Period and Frequency for Collecting AE and SAE Information.......47
8.3.1.1. Reporting SAEs to Pfizer Safety...............................................47
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF...................47
8.3.2. Method of Detecting AEs and SAEs ..........................................................48
8.3.3. Follow-up of AEs and SAEs.......................................................................48
8.3.4. Regulatory Reporting Requirements for SAEs...........................................48
8.3.5. Exposure During Pregnancy or Breastfeeding, and Occupational 
Exposure ..........................................................................................................48
8.3.5.1. Exposure During Pregnancy......................................................49
8.3.5.2. Exposure During Breastfeeding ................................................50
8.3.5.3. Occupational Exposure .............................................................51
8.3.6. Cardiovascular and Death Events...............................................................51
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs..............................................................................51
8.3.8. Adverse Events of Special Interest.............................................................51
8.3.8.1. Lack of Efficacy........................................................................51
8.3.9. Medical Device Deficiencies......................................................................51
8.3.10. Medication Errors.....................................................................................51
8.4. Treatment of Overdose............................................................................................52
8.7. Genetics...................................................................................................................54
8.7.1. Specified Genetics ......................................................................................54
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8.7.2. Banked Biospecimens for Genetics............................................................54
8.8.2. Banked Biospecimens for Biomarkers .......................................................56
8.8.3. Specified Gene Expression (RNA) Research .............................................56
8.8.4. Specified Protein Research.........................................................................56
8.8.5. Specified Metabolomic Research ...............................................................56
8.9. Immunogenicity Assessments.................................................................................56
8.10. Health Economics .................................................................................................56
9. STATISTICAL CONSIDERATIONS ................................................................................56
9.1. Statistical Hypotheses .............................................................................................56
9.2. Sample Size Determination.....................................................................................57
9.3. Analysis Sets ...........................................................................................................57
9.4. Statistical Analyses .................................................................................................57
9.4.1. Safety Analyses ..........................................................................................58
9.4.1.1. Electrocardiogram Interval Analyses ........................................58
9.4.2. PK Analyses................................................................................................59
9.4.2.1. Derivation of PK Parameters.....................................................59
9.4.2.2. Statistical Methods for PK Data................................................60
9.4.3. Other Analyses............................................................................................60
9.5. Interim Analyses .....................................................................................................60
9.6. Data Monitoring Committee or Other Independent Oversight Committee.............60
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS..........................................................................................................61
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations...............61
10.1.1. Regulatory and Ethical Considerations ....................................................61
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP.........................................................................61
10.1.2. Financial Disclosure .................................................................................62
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10.1.3. Informed Consent Process ........................................................................62
10.1.4. Data Protection .........................................................................................63
10.1.5. Dissemination of Clinical Study Data ......................................................63
10.1.6. Data Quality Assurance ............................................................................65
10.1.7. Source Documents....................................................................................66
10.1.8. Study and Site Start and Closure ..............................................................66
10.1.9. Publication Policy.....................................................................................67
10.1.10. Sponsor’s Qualified Medical Personnel .................................................68
10.2. Appendix 2: Clinical Laboratory Tests .................................................................69
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-up, and Reporting ......................................................................70
10.3.1. Definition of AE .......................................................................................70
10.3.2. Definition of SAE.....................................................................................71
10.3.3. Recording/Reporting and Follow-up of AEs and/or SAEs.......................73
10.3.4. Reporting of SAEs....................................................................................76
10.4. Appendix 4: Contraceptive Guidance ...................................................................77
10.4.1. Male Participant Reproductive Inclusion Criteria....................................77
10.4.2. Female Participant Reproductive Inclusion Criteria.................................77
10.4.3. Woman of Childbearing Potential ............................................................77
10.4.4. Contraception Methods.............................................................................78
10.5. Appendix 5: Genetics............................................................................................80
10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-up Assessments ........81
10.7. Appendix 7: ECG Findings of Potential Clinical Concern ...................................83
10.10. Appendix 10: Abbreviations ...............................................................................89
11. REFERENCES ..................................................................................................................93
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LIST OF TABLES
Table 2.
Plasma PK Parameters..............................................................................59
Table 3.
Protocol Required Safety Laboratory Assessments..................................69
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1. PROTOCOL SUMMARY
1.1. Synopsis 
Short Title: A Phase 1 Study of Single Ascending Doses of PF-07258669 in Healthy Adult 
Participants
Rationale: This study is the first clinical study with PF-07258669. The safety, tolerability, 
and plasma PK of PF-07258669 after administration of escalating, single, oral doses will be 
evaluated.
Objectives and Endpoints:
Objectives
Endpoints
Primary: 
Primary: 
•
To evaluate the safety and tolerability of single 
ascending doses of PF-07258669 administered 
orally to healthy adult participants.
•
Assessment of adverse events, clinical safety 
laboratory tests, vital signs, continuous cardiac 
monitoring, 12-lead electrocardiograms, 
respiratory rate, oral body temperature, physical
examinations, and neurological examinations.
Secondary: 
Secondary: 
•
To evaluate the pharmacokinetics of 
PF-07258669 following single doses of 
PF-07258669 administered orally to healthy 
adult participants.
•
PK parameters derived from plasma PF-07258669
concentrations: Cmax, AUClast, AUCinf, Tmax, and 
t½, if data permit.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Overall Design: This study is a randomized, investigator- and participant-blind, 
sponsor-open, placebo-controlled, first-in-human, single ascending oral dose study of 
PF-07258669 administered to healthy adult participants. Precautionary sentinel dosing will 
be used in each period of each cohort. Two participants (1 receiving PF-07258669 and 
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1 receiving placebo) within a period will be dosed initially before the remaining participants 
of that period are dosed. Safety and tolerability data through at least 24 hours post-dose for 
the sentinel participants will be reviewed prior to dosing the remaining participants of that 
period.
Number of Participants: A maximum of approximately 24 participants will be randomized 
in this study (8 per cohort). 
Intervention Groups and Duration: The study interventions include PF-07258669 and 
placebo. Both will be administered as extemporaneously-prepared solutions or suspensions 
for oral administration. Participants will receive single doses in each period of the study. 
Data Monitoring Committee or Other Independent Oversight Committee: No.
Statistical Methods: The sample size has been chosen based on the need to minimize first
exposure to humans of a new chemical entity and the requirement to conduct adequate safety,
toleration, and PK assessments at each dose level.
All safety analyses will be performed on the safety analysis set, which is defined as all 
participants randomly assigned to study intervention and who receive a dose of study 
intervention.  Participants will be analyzed according to the product they actually received.
Safety data will be presented in tabular and/or graphical format and summarized 
descriptively, where appropriate. 
The PK parameters for PF‑07258669 following oral dose administration will be derived from 
the plasma concentration‑time profiles. PK parameters and concentrations of PF-07258669 
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1.2. Schema

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1.3. Schedule of Activities
The SoA table provides an overview of the protocol visits and procedures.  Refer to the STUDY ASSESSMENTS AND 
PROCEDURES section of the protocol for detailed information on each procedure and assessment required for compliance with the 
protocol. The investigator may schedule visits (unplanned visits) in addition to those listed in the SoA table, in order to conduct 
evaluations or assessments required to protect the well-being of the participant.
Visit Identifiera
Screening
Period 1 to Period 4b
Follow-Up
ET/DC
Day -28 
to Day -2
Day 
-1
Day 1
Day 
2
Day 
3
Visit: 
Day 
8±2c
Contact: 
28-35
Daysc
Hours After Dose
0d
0.17 0.5
1
1.5
2
4
6
8
10
12
16
24
36
48
Informed consent and demography
X
Outpatient visit
X
X
Inpatient stay at CRU
X
→
→
→
→
→
→
→
→
→
→
→
→
→
→
Xe
Review inclusion/exclusion criteria
X
Xf
Medical/medication history
X
Xf
History of alcohol, tobacco, and illegal drug use
X
Xf
Contraception checkg
X
X
X
X
X
X
COVID-19 questionnaireh
X
X
COVID-19 testi
X
X
X
COVID-19 body temperature check
X
X
X
X
X
X
X
X
X
Physical exam (height and weight at Screening
only)j
X
X
Neurological examination
X
X
X
X
X
X
X
Review concomitant treatments
X
X
X
X
X
Respiratory rate
X
X
X
X
X
X
X
X
X
Oral body temperature
X
X
X
X
X
X
X
X
12-Lead ECGk
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Supine BP and PR
X
X
X
X
X
X
X
X
X
X
X
Orthostatic (supine and standing) BP and PR
X
X
X
Continuous cardiac telemetryl
X
→
→
→
→
→
→
→
X
Serious/nonserious AE monitoring
X
→
→
→
→
→
→
→
→
→
→
→
→
→
→
→
→
→
X
X
Blinded study intervention administrationo
Xp
Blood Samples for:
Clinical safety laboratory tests, including lipid 
panelq
X
X
X
X
X
X
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Visit Identifiera
Screening
Period 1 to Period 4b
Follow-Up
ET/DC
Day -28 
to Day -2
Day 
-1
Day 1
Day 
2
Day 
3
Visit: 
Day 
8±2c
Contact: 
28-35
Daysc
Hours After Dose
0d
0.17 0.5
1
1.5
2
4
6
8
10
12
16
24
36
48
Serum FSHr
X
HBcAb, HBsAg, HBsAb, HCVAb, HIV testing
X
Pfizer Prep B2 banked samples
X
Pfizer Prep D1.5 banked samples
X
PF-07258669 plasma pharmacokinetics
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Samples for:
Urine drug test 
X
X
Clinical safety laboratory testsq
X
X
X
X
X
X
Abbreviations: →= ongoing/continuous event; AE = adverse event; BP = blood pressure; CRU = clinical research unit; DC = discontinuation; ECG = electrocardiogram; 
ET = early termination; FSH = follicle stimulating hormone; HBcAb = hepatitis B core antibody; HBsAb = hepatitis B antibody; HBsAg = hepatitis B surface antigen; 
HCVAb = hepatitis C antibody; HIV = human immunodeficiency virus; PR = pulse rate.
a.
Day relative to start of study treatment (Day 1).
b.
There will be a washout interval of ≥7 days between doses within an individual participant.
c.
Onsite follow-up visit to occur on Day 8 ±2 days in Period 4 only. Follow-up contact may occur via telephone contact and must occur 28-35 days after administration of the 
final dose of study intervention.
d.
Day 1 activities at time=0 hours are prior to the dose, except for study treatment administration.
e.
Participants may be confined to the CRU after completion of Day 3 activities at the discretion of the investigator or if safety, tolerability, or PK data dictate the need to 
prolong confinement in the CRU.
f.
Period 1 only. Review any changes from Screening.
g.
Contraception only required for male study participants and is recommended for partners of male study participants who are WOCBP.
h.
COVID-19 questionnaire includes check for suspected contact, risk zone, and COVID-19 related symptoms.
i.
Testing for active COVID-19 infection via testing for SARS-CoV-2 viral dosing (using PCR). To meet PCRU practice, testing for active COVID-19 infection will be
performed at screening, admission, and follow-up visit.
j.
Complete physical examination must either be conducted at Screening or upon admission in Period 1 only.  Limited physical examination may be performed at admission on 
Day -1 in Period 1 if a complete physical examination is performed at Screening.  Limited physical examinations may be performed as appropriate at other times at the 
investigator’s discretion if there are findings during the previous examination or new/open adverse events.
k.
Single 12-lead ECG at Screening. Triplicate 12-lead ECGs at all other timepoints.
l.
Baseline telemetry to be recorded for at least 2 hours prior to the first dose in Period 1 only.  This may be done immediately prior to dosing or at some 2 hour continuous 
interval in the 24 hours prior to dosing, as long as the participant is awake.  Post-dose telemetry will continue for 8 hours after dosing.
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o.
Precautionary sentinel dosing will be used in each period of each cohort. Two participants (1 receiving PF-07258669 and 1 receiving placebo) within a period will be dosed 
initially before the remaining participants of that period are dosed. Safety and tolerability data through at least 24 hours post-dose for the sentinel participants will be
reviewed prior to dosing the remaining participants of that period.
p.
Participants should fast for at least 10 hours prior to dosing.
q.
Participants should fast for at least 12 hours prior to sample collection.
r.
Females who have been amenorrheic for at least 12 months.
s.
Period 1 only. If not collected on the designated collection day, collect at the next available time when biospecimens are being collected in conjunction with a participant visit.
C
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2. INTRODUCTION
PF-07258669 is an MC4R antagonist 
 
2.1. Study Rationale 
This study will be the first time PF-07258669 is administered to humans. The purpose of the 
study is to evaluate the safety, tolerability, and PK of PF-07258669 following administration 
of single oral doses to healthy adult participants.
2.2. Background 
2.2.1. MC4R 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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2.2.5. Nonclinical Safety 
PF-07258669 was evaluated in a series of safety pharmacology and toxicity studies in rats 
and dogs up to 1 month in duration, as well as in a battery of genetic toxicity studies. 
 
 
 
 
 
 
 
 
 
The NOAELs in the pivotal 1-month toxicity studies 
were 100 mg/kg/day in rats (total Cmax of 25,000 ng/mL and AUC of 224,000 ng•h/mL in 
males) and 30/60 mg/kg/day in male/female dogs (total Cmax of 13,200 ng/mL and AUC of 
159,000 ng•h/mL in males).  PF-07258669 is not genotoxic 
 
  Details of the nonclinical safety program are provided in the investigator’s 
brochure.
2.3. Benefit/Risk Assessment
This study is the first time that PF-07258669 will be administered to humans and is designed 
primarily to generate safety, tolerability, and PK data for further clinical development.
PF-07258669 is not expected to provide any clinical benefit to healthy participants. The 
purpose of the study is to provide the basis for further clinical development of PF-07258669
 
As of October 2020, no specific human risks have been identified; 
 
 The clinical impact of these 
potential risks will be minimized through the proposed cautious dose-escalation process 
wherein higher doses of PF-07258669 will be administered only after lower doses have been 
found to be well tolerated with an acceptable safety profile.  In addition, this study will use 
sentinel dosing and includes standard, intensive, inpatient monitoring of all participants 
following administration of single, oral doses of the study intervention.
More detailed information about the known and expected benefits and risks and reasonably 
expected adverse events of PF-07258669 may be found in the investigator’s brochure, which 
is the SRSD for this study.
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2.3.2. Benefit Assessment
The participants in this study are not expected to obtain any specific benefit beyond 
contributing to the process of developing new therapies in an area of unmet need.  They will 
receive close monitoring of their safety via study procedures undertaken (eg, physical 
examinations, 12-lead ECGs, vital signs) which will occur as outlined in this protocol.  
2.3.3. Overall Benefit/Risk Conclusion
Based on the totality of available nonclinical data, and taking into account the measures 
taken to minimize risk to participants participating in this study, the overall benefit/risk 
profile supports clinical testing of PF-07258669.
3. OBJECTIVES AND ENDPOINTS
Objectives
Endpoints
Primary: 
Primary: 
•
To evaluate the safety and tolerability of single 
ascending doses of PF-07258669 administered 
orally to healthy adult participants.
•
Assessment of adverse events, clinical safety laboratory 
tests, vital signs, continuous cardiac monitoring, 
12-lead electrocardiograms, respiratory rate, oral body 
temperature, physical examinations, and neurological 
examinations.
Secondary:
Secondary: 
•
To evaluate the pharmacokinetics of PF-07258669 
following single doses of PF-07258669
administered orally to healthy adult participants.
•
PK parameters derived from plasma PF-07258669
concentrations: Cmax, AUClast, AUCinf, Tmax, and t½, if 
data permit.
 
 
 
 
 
 
 
 
 
 
 
 
 
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4. STUDY DESIGN
4.1. Overall Design
This study is a randomized, investigator- and participant-blind, sponsor-open, 
placebo-controlled, first-in-human, single ascending oral dose study of PF-07258669 
administered to healthy adult participants. Up to approximately 24 healthy adult participants
(up to 3 cohorts of approximately 8 participants each) will be enrolled in this study. Each 
participant is planned to undergo 4 treatment periods receiving 3 doses of PF-07258669 and 
1 dose of placebo.
Precautionary sentinel dosing will be used in each period of each cohort. Two participants 
(1 receiving PF-07258669 and 1 receiving placebo) within a period will be dosed initially 
before the remaining participants of that period are dosed. Safety and tolerability data 
through at least 24 hours post-dose for the sentinel participants will be reviewed prior to 
dosing the remaining participants of that period.
Dose levels will be escalated to bracket the expected clinical dose range, but projected
exposures will not exceed the pre-defined human exposure limits. The optional third cohort 
will only be used if the objectives of the study are not fulfilled in Cohort 1 and Cohort 2. 
The total duration of participation from the screening visit to the telephone follow-up contact
will be approximately 14 weeks.
If a participant drops out before completing all study periods within a cohort, or withdraws 
for reasons unrelated to the safety of the study intervention, the participant may be replaced 
at the discretion of the investigator and sponsor. The replacement participant(s) may or may 
not be required to complete all periods of the cohort in which they are participating at the
discretion of the investigator and sponsor.
4.2. Scientific Rationale for Study Design
The population planned for this study will be healthy males and females of nonchildbearing 
potential. Female participants will be confirmed not to be of childbearing potential because 
embryo-fetal developmental toxicity studies with PF-07258669 have not been conducted.  In 
male participants, appropriate measures are expected to be followed to minimize potential 
transfer of PF-07258669 via semen to partners (see Appendix 4).
Because this is the first time PF-07258669 will be administered to humans, an escalating 
single oral dose design is planned with careful assessment and ongoing review of safety, 
tolerability, and PK data of PF-07258669. Sentinel dosing will also be utilized in each 
period to ensure that safety and tolerability data in a subset of 2 participants within each 
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At each dose level, 6 participants are planned to receive PF-07258669 and 2 participants are 
planned to receive placebo with all participants at the end of the study having received 1 dose 
of placebo and 3 doses of PF-07258669. In addition, the highest anticipated Cmax and AUC24
PF-07258669 will not exceed the pre-identified human exposure stopping limits nor exceed 
the highest feasible total daily dose of 2000 mg.
The design permits both within- and between-participant assessments of safety, tolerability, 
and PK. Furthermore, to permit an unbiased assessment of safety, the administration of both 
PF-07258669 and placebo in each period will be double-blinded to both site staff (except 
those involved in preparation of doses) as well as the participants. 
PK samples are planned to be collected over 48 hours post-dose. However, sampling times, 
duration of sampling, and/or the length of the washout period may be modified and/or 
extended if data generated in previous periods indicate that the half-life is longer than 
predicted.
There will be a washout interval of ≥7 days between doses within an individual participant, 
which is deemed sufficient based on the predicted PF-07258669 effective half-life 
 
. In addition, this interval accounts for the required time for review of 
the safety, tolerability, and PK data from each dosing period before making a decision on the 
subsequent PF-07258669 dose to be evaluated. The planned doses in the escalation sequence 
(Table 1 and Section 1.2) may be modified or repeated, as guided by emerging safety, 
tolerability, and PK data but will follow the dose-escalation rules defined in Section 6.6.1. 
 
 
 
 
 
 
 
 
 
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Although there is no suspicion of human teratogenicity based on the expected pharmacology 
of PF-07258669, human reproductive safety data are not available for PF-07258669. 
Therefore, the use of a highly effective method of contraception is required for male study 
participants and is recommended for partners of male study participants who are WOCBP
(see Appendix 4).
Banked Biospecimens will be collected and stored for further analyses which may, for 
example, provide greater understanding of the study intervention.
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4.3. Justification for Dose
The proposed dose levels of PF-07258669 were derived based on cumulative nonclinical data
including in vitro and in vivo pharmacology and PK data and the completed nonclinical 
toxicity studies. Dose levels have been selected to bracket the expected clinical dose and 
exposure range, while considering uncertainty in the projected clinically efficacious dose. 
Dose levels beyond the starting dose may be modified based on emerging human safety, 
tolerability, and PK data in the current study.
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
4.3.2. Human Exposure Stopping Limits
The human exposure stopping limits are based on exposures observed in dogs in nonclinical 
toxicology studies and are corrected for species-dependent plasma protein binding between 
dog and human 
. 
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The human AUC24 stopping limit is based on the NOAEL in male dogs (30 mg/kg/day) in 
4-week GLP toxicology study. The total AUC24 in male dogs was 159,000 ng·h/mL, which 
is the lowest AUC24 observed at the NOAEL across all toxicology studies in rats and dogs. 
After correcting for protein binding differences between dog and human, the human AUC24
stopping limit is a total AUC24 of 212,000 ng·h/mL.
4.3.3. Rationale for Dose Selection
The safety, tolerability, and plasma PK of PF-07258669, after administration of single 
escalating oral doses across a wide dose/exposure range, will be evaluated in this study. 
Dosing will occur in the fasted state. The doses presented in Table 1 are projected based on 
nonclinical data and may be modified based on emerging human safety, tolerability, and PK 
data. Human PK parameter estimates, toxicokinetic data, and projected effective 
concentrations were used to establish the initial range of planned doses in this study. The 
projected human exposures assume dose-proportional increases in exposure within the 
planned dose range. 
 
 
 
 
 
 
 
 
 
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Due to the 
 projected t½ of PF-07258669, plasma concentrations are expected to 
decrease rapidly upon attainment of Cmax. 
 
 
 
 
 
Therefore, given that the predicted exposure 
following a dose of 0.1 mg is not expected to result in any biological activity and affords 
large margins over the human Cmax stopping limit, it is deemed an appropriate starting dose 
level for this study.
The dose range to be studied was selected to account for uncertainties in the projected Ceff
and the projected therapeutic dose, while also bracketing the expected clinically effective 
dose range in humans 
 
and providing safety coverage for a wide range of PF-07258669 doses.
Assessment of the safety, tolerability, and PK after each single dose level will be conducted 
before escalating to the next dose level. The dose/exposure-escalation increments are 
planned to be up to approximately semi-logarithmic increases in exposure from the previous 
highest dose. The actual dose levels, target exposures, and/or dose level increments may be 
adjusted (higher or lower) during the study based on emerging human safety, tolerability, and 
PK data, but projected exposures will not exceed the predefined human exposure limits. If 
Cmax-related adverse events are observed, split dosing may be used to potentially increase 
AUC without increasing Cmax. Dose levels may also be repeated if warranted.
4.4. End of Study Definition
A participant is considered to have completed the study if he/she has completed all phases of 
the study, including the last scheduled procedure shown in the SoA.
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.
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.
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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. Female participants of nonchildbearing potential and males must be 18 to 55 years of 
age, inclusive, at the time of signing the ICD.

Refer to Appendix 4 for reproductive criteria for male (Section 10.4.1) and female 
(Section 10.4.2) participants.
Type of Participant and Disease Characteristics:
2. Female participants of non-child bearing potential and male participants and who are 
overtly healthy as determined by medical evaluation including medical history, 
physical examination, neurological examination, laboratory tests, and cardiac 
monitoring.
3. Participants who are willing to avoid direct sunlight exposure or any high intensity 
ultraviolet light exposure from admission to the follow-up contact and to apply 
sunscreen/lotion with a high sun protection factor, as appropriate.
4. Participants who are willing and able to comply with all scheduled visits, treatment 
plan, laboratory tests, lifestyle considerations, and other study procedures.
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. 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), as well as presence of lipid panel 
abnormalities (eg, hypercholesterolemia, hypertriglyceridemia).

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2. Evidence of history of orthostatic hypotension or symptomatic bradycardia.
3. Any condition possibly affecting drug absorption (eg, gastrectomy, cholecystectomy).  
4. History of phototoxicity or photosensitivity.
5. History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, 
hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb) or 
hepatitis C antibody (HCVAb).  Hepatitis B vaccination is allowed. As an exception 
a positive HBsAb test due to hepatitis B vaccination is permissible.
6. Other medical or psychiatric condition including recent (within the past year), or 
active suicidal ideation/behavior, or laboratory abnormality, or other condition or 
situation related to the COVID-19 pandemic 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 6.5 for additional details).
Prior/Concurrent Clinical Study Experience:
8. 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). 
Diagnostic Assessments:
9. A positive urine drug test at screening or admission and confirmed by a single repeat 
test, if deemed necessary.
10. 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.
11. Current findings or documented past history of blood pressure values <90 mmHg 
systolic or <50 mmHg diastolic.
12. 12-lead ECG that demonstrates clinically relevant abnormalities that may affect 
participant safety or interpretation of study results (eg, baseline QTc interval 
>450 msec, complete LBBB, signs of an acute or indeterminate-age myocardial
infarction, ST-T interval changes suggestive of myocardial ischemia, second- or 
third-degree AV block, or serious bradyarrhythmias or tachyarrhythmias).  If the 

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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 QTc exceeds 450 msec, or QRS exceeds 120 msec, the ECG 
should be repeated 2 more times and the average of the 3 QTc 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 
participants.
13. 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 ≥1.0× ULN;

Total bilirubin level ≥1.5 × ULN; participants with a history of Gilbert's 
syndrome may have direct bilirubin measured and would be eligible for this study 
provided the direct bilirubin level is ≤ULN;

Any lipid panel parameter (ie, total cholesterol, triglycerides, HDL, and/or LDL)
≥1.25× ULN.
14. A positive COVID-19 test.
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 equivalent of 
5 cigarettes/day or 2 chews of tobacco/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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5.3. Lifestyle Considerations
The following guidelines are provided:
5.3.1. Meals and Dietary Restrictions

Participants must abstain from all food and drink (except water) at least 12 hours 
prior to any safety laboratory evaluations and 10 hours prior to the collection of the 
predose PK sample.

Water is permitted until 1 hour prior to study intervention administration.  Water may 
be consumed without restriction beginning 1 hour after dosing.  Noncaffeinated 
drinks (except 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 dosing.

Dinner will be provided approximately 9 to 10 hours after 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 (or as specified above for 
red wine) to admission to the CRU and continue abstaining from alcohol until 
collection of the final PK sample of each study period.  Participants may undergo an 
alcohol breath test or blood alcohol test at the discretion of the investigator.

Participants will abstain from the use of tobacco- or nicotine-containing products for 
≥24 hours prior to dosing and during confinement in the CRU.
5.3.3. Activity

Participants will abstain from strenuous exercise (eg, heavy lifting, weight training, 
calisthenics, aerobics) for at least 48 hours prior to each blood collection for clinical 
laboratory tests.  Walking at a normal pace will be permitted.

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
In order to standardize the conditions on PK sampling days, participants will be 
required to refrain from lying down (except when required for BP, pulse rate, and 
ECG measurements), eating, and drinking beverages other than water during the first 
4 hours after dosing.

Participants will be confined to the procedure room for the first 4 hours after dosing 
on Day 1 during continuous cardiac monitoring, except to use the bathroom.  After 
this, if the equipment setup allows, participants may be ambulatory during the ECG 
monitoring period, but should not engage in strenuous activities.  If equipment does 
not allow ambulation, appropriate accommodations will be made by the investigator 
site to facilitate continuous monitoring (eg, bedside urinals should be provided to 
accommodate participants’ excretory needs).

Participants will be advised to avoid direct sunlight exposure or any high intensity 
UV light exposure, from admission in Period 1 through the follow-up contact. In 
addition, participants will be instructed to apply sun cream/lotion with a sun 
protection factor (SPF) of ≥50, as appropriate.
5.3.4. Contraception
Contraception is only required for male study participants and is recommended for partners 
of male study participants who are WOCBP.
The investigator or his or her designee, in consultation with the participant, will confirm that 
the participant has selected an appropriate method of contraception for the individual 
participant and his or her partner(s) from the permitted list of contraception methods (see 
Appendix 4 Section 10.4.4) and will confirm that the participant has been instructed in its
consistent and correct use.  At time points indicated in the schedule of activities (SoA), the 
investigator or designee will inform the participant of the need to use highly effective 
contraception consistently and correctly and document the conversation and the participant’s 
affirmation in the participant’s chart (participants need to affirm their consistent and correct 
use of at least 1 of the selected methods of contraception).  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 randomly assigned to study intervention/enrolled in the study. Screen 
failure data are collected and remain as source and are not reported to the clinical database.
Individuals who do not meet the criteria for participation in this study (screen failure) may 
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6. STUDY INTERVENTION
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 all of the following:

PF-07258669;

Placebo for PF-07258669.
6.1. Study Intervention(s) Administered
PF-07258669 and placebo will be provided by Pfizer as bulk powders for extemporaneous 
preparation of oral solutions and suspensions at the CRU.
PF-07258669 and placebo will be presented to the participants in individual dosing 
containers.
6.1.1. Administration
Following an overnight fast of at least 10 hours, participants will receive study intervention 
at approximately 0800 hours (plus or minus 2 hours) without breakfast on Day 1.
Investigator site personnel will administer a single oral dose of study intervention on Day 1 
of each period with ambient temperature water to a total volume of approximately 240 mL. 
Study intervention will be administered according to the EDR.
6.2. Preparation/Handling/Storage/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 CRU 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. See the EDR for storage conditions of the study intervention once prepared.
7. 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.
8. Further guidance and information for the final disposition of unused study 
interventions are provided in the CRU 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-07258669 and placebo oral dosing solutions and suspensions will be prepared in the CRU 
by 2 operators, 1 of whom is a pharmacist.  Details of dose preparation will be given in a 
separate EDR.  Prepared doses will be provided in unit dose containers and labeled in 
accordance with Pfizer regulations and the investigator site’s labeling requirements.

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6.3. Measures to Minimize Bias: Randomization and Blinding
6.3.1. Allocation to Study Intervention
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.
Participants will be randomly assigned to receive study intervention from a central 
randomization scheme.  Investigators and participants will remain blinded to each 
participant’s assigned study intervention throughout the course of the study. In order to 
maintain this blind, an otherwise uninvolved third party (for example, pharmacist) will be 
responsible for the preparation and dispensing of all study intervention according to the 
randomization schedule and assigned treatment for the individual participant.
6.3.2. Breaking the Blind
The method for breaking the blind in this study will be manual.  In case of an emergency, the 
investigator has the sole responsibility for determining if unblinding of a participant’s 
treatment assignment is warranted. Participant safety must always be the first consideration 
in making such a determination.  If the investigator decides that unblinding is warranted, the 
investigator should make every effort to contact the sponsor prior to unblinding a 
participant’s treatment assignment unless this could delay further management of the 
participant. If a participant’s treatment assignment is unblinded, the sponsor must be notified 
within 24 hours after breaking the blind. When the blinding code is broken, the reason must 
be fully documented in the CRF.
Blood specimens will be obtained from all participants for PK analysis to maintain the study 
blind at the investigator site.  Only the investigator site staff and blinded study monitor, if 
assigned, will be blinded to study treatment.  A limited number of Pfizer study team 
personnel will be unblinded to participant treatments in order to permit real-time 
interpretation of the safety and PK data and provide information necessary to potentially alter 
the dose-escalation sequence.  The blinded study monitor, if assigned, will remain blinded to 
treatment until all monitoring for the study has been completed.  Specimens from participants 
randomized to placebo will not be routinely analyzed.  To minimize the potential for bias, 
treatment randomization information will be kept confidential by Pfizer unblinded personnel 
and will not be released to the blinded investigator or blinded investigator site personnel until 
the study database has been locked or the investigator requests unblinding for safety reasons.
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 clinic 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.

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6.5. Concomitant Therapy
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 through the follow-up contact.  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.
Females taking hormone replacement therapy may be eligible to participate in this study if 
they are willing to discontinue therapy at least 28 days prior to the first dose of study 
treatment and remain off hormonal therapy for the duration of the study.
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 clinic visit.
Treatments taken within 28 days before the first dose of study intervention will be 
documented as a prior treatment.  Treatments taken after the first dose of study intervention
will be documented as concomitant treatments.
6.5.1. Rescue Medicine
There is no rescue therapy to reverse the AEs observed with PF-07258669; standard medical 
supportive care must be provided to manage the AEs. 
6.6. Dose Modification
The decision to proceed to the next dose level of PF-07258669 (eg, an increase, decrease, or 
repeat of a previous dose level) will be made by the study team and the investigator based on 
safety, tolerability, and preliminary PK data at the prior dose level. At least 6 participants 
(including at least 1 placebo participant) must complete the prior dose level. PK data through 
at least 24 hours post-dose will be reviewed.
The dosing schedule may also be adjusted to add cohorts (8 participants/cohort) to evaluate 
additional dose levels. The study procedures for these additional participant(s)/cohort(s) will 
be the same as that described for other study participants/cohorts.
6.6.1. Dose Escalation and Stopping Rules
Precautionary sentinel dosing will be used in each period of each cohort. Two participants 
(1 receiving PF-07258669 and 1 receiving placebo) within a period will be dosed initially 
before the remaining participants of that period are dosed. Safety and tolerability data 
through at least 24 hours post-dose for the sentinel participants will be reviewed prior to 
dosing the remaining participants of that period.

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Dose escalation stopping rules will be used to determine whether the maximal tolerated dose 
has been attained.  Dose escalation may be stopped if it is determined that the limits of safety 
and/or tolerability have been reached.  This decision will be made after a discussion takes
place between the sponsor study team and the investigator.  The sponsor study team may not 
overrule the investigator’s decision to stop dose escalation.  If dose escalation is stopped 
because of any of these criteria, additional cohorts may receive the same or lower doses of 
the study intervention.
The dose escalation will be terminated based on the following criteria:
•
If 50% or more of the participants receiving active drug at a given dose level (but not 
participants receiving placebo) develop similar clinically significant laboratory, ECG, 
or vital sign abnormalities, in the same organ class, indicating dose-limiting 
intolerance.
•
Severe nonserious AEs, considered as, at least, possibly related to study intervention
administration, in 2 participants at a given dose level (but not participants receiving 
placebo), independent of within or not within the same system organ class, indicating 
dose-limiting intolerance.
•
Dosing will be paused for any SAE that occurs in a participant receiving active 
treatment until causality is fully assessed by the PI and sponsor.  Dosing may resume 
if the SAE is determined to be not drug-related by the PI and sponsor.  If the SAE is 
determined to be either drug-related or unknown, either dosing will cease or the SAE 
will be evaluated by the sponsor’s protocol review committee (or similar review 
group), which is independent of the study team and investigators.  If the protocol 
review committee determines that dosing may resume, a plan that mitigates risks to 
participants with the resumption of dosing will be implemented.  Such a plan could 
include a revision of inclusion/exclusion criteria, repeating or reducing the dose, or 
adding appropriate safety monitoring.
•
It is determined that the limit of safety and/or tolerability has been reached.  This 
decision will be made following discussions between the study team and the 
investigator.
•
Other findings that, at the discretion of the study team and investigator, indicate that 
dose escalation should be halted.
•
 
•
If, based on the observed data, the group mean Cmax or AUC (based on total plasma 
concentration) of the next planned dose is projected to exceed the escalation limits, 
that dose will not be explored.  Modified doses may be explored if they are not 
expected to exceed PK stopping criteria.
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Progression to the next dose level will occur if the last dose was well tolerated and after 
satisfactory review of the available safety and PK data.
At a minimum, review of safety and tolerability data through 48 hours post-dose, and PK 
data through 24 hours post-dose, is required in order to escalate to the next dose level. The 
safety and tolerability assessments are outlined in the study endpoints and include assessment 
of adverse events, clinical safety laboratory tests, vital signs, continuous cardiac monitoring, 
12-lead electrocardiograms, respiratory rate, oral body temperature, physical examinations, 
and neurological examinations.
6.7. Intervention After the End of the Study
No intervention will be provided to study participants at the end of the study.
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL
7.1. Discontinuation of Study Intervention
In rare instances, it may be necessary for a participant to permanently discontinue study 
intervention (definitive discontinuation). Reasons for definitive discontinuation of study 
intervention include the following: adverse event, or some other (administrative) reason.
If study intervention is definitively 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.
In the event of discontinuation of study intervention, it must be documented on the 
appropriate CRF/in the medical records whether the participant is discontinuing further 
receipt of study intervention or also from study procedures, posttreatment study follow-up, 
and/or future collection of additional information.
ECG Changes
A participant who meets either of the following bulleted criteria 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.

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Potential Cases of Acute Kidney Injury
Abnormal values in SCr concurrent with presence or absence of increase in BUN that meet 
the criteria below, in the absence of other causes of kidney injury, are considered potential 
cases of acute kidney injury and should be considered important medical events. 
An increase of ≥0.3 mg/dL (or ≥26.5 µmol/L) in SCr level relative to the participant’s own 
baseline measurement should trigger another assessment of SCr as soon as practically 
feasible, preferably within 48 hours from awareness.
If the second assessment (after the first observations of ≥0.3 mg/dL [or ≥26.5 µmol/L] in SCr
relative to the participant’s own baseline measurement) is ≥0.4 mg/dL (or ≥35.4 µmol/L), the 
participant should be discontinued from the study and adequate, immediate, supportive 
measures taken to correct apparent acute kidney injury.
Participants should return to the investigator site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the second assessment confirming abnormal 
SCr result.  This evaluation should include laboratory tests, detailed history, and physical 
assessment.  In addition to repeating SCr, laboratory tests should include serum BUN, serum 
creatine kinase, and serum electrolytes (including at a minimum potassium, sodium, 
phosphate/phosphorus, and calcium), in addition to urinary dipstick, urine microscopic 
examination, and urinary indices.  All cases confirmed on repeat testing as meeting the 
laboratory criteria for acute kidney injury, with no other cause(s) of laboratory abnormalities 
identified, should be considered potential cases of drug-induced kidney injury irrespective of 
availability of all the results of the investigations performed to determine etiology of the 
abnormal SCr.  If ≥2 healthy participants in a given period 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.
7.2. 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 follow-up;

Lost to follow-up;

Death;

Study terminated by sponsor;

Discretion of the investigator or sponsor for safety or behavioral reasons, or the 
inability of the participant to comply with the protocol required schedule of study 
visits or procedures.

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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 
received at least 1 dose of the study intervention and then are prematurely withdrawn from 
the study.  Participants should be questioned regarding their reason for withdrawal.
The participant will be permanently discontinued both from the study intervention and from 
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.
Lack of completion of all or any of the withdrawal/early termination procedures will not be 
viewed as protocol deviations so long as the participant’s safety was preserved.
7.2.1. Withdrawal of Consent 
Participants who request to discontinue receipt of study intervention will remain in the study 
and must continue to be followed for protocol-specified follow-up procedures.  The only 
exception to this is when a participant specifically withdraws consent for any further contact 
with him or her or persons previously authorized by the participant to provide this 
information.  Participants should notify the investigator in writing of the decision to 
withdraw consent from future follow-up, whenever possible.  The withdrawal of consent 
should be explained in detail in the medical records by the investigator, as to whether the 
withdrawal is only from further receipt of study intervention or also from study procedures 
and/or posttreatment study follow-up, and entered on the appropriate CRF page.  In the event 
that vital status (whether the participant is alive or dead) is being measured, publicly 
available information should be used to determine vital status only as appropriately directed 
in accordance with local law.
7.3. Lost to Follow-up 
A participant will be considered lost to follow-up if he or she repeatedly fails to return for 
scheduled visits and is unable to be contacted by the study site.
The following actions must be taken if a participant fails to return to the clinic for a required 
study visit:

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
The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible and counsel the participant on the importance of maintaining the 
assigned visit schedule and ascertain whether or not 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.
A participant who qualified for this protocol but did not enroll from an earlier cohort/group 
may be used in a subsequent cohort/group without rescreening, provided laboratory results 
obtained prior to the first dose administration meet eligibility criteria for this study.  In 
addition, other clinical assessments or specimen collections, eg, banked biospecimens, may 
be used without repeat collection, as appropriate.

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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 
(pulse rate 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 
475 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 60 consecutive 
days.
To prepare for study participation, participants will be instructed on the information in the 
Lifestyle Considerations and Concomitant Therapy sections of the protocol.
8.1. Efficacy Assessments
No efficacy assessments are being conducted in this study.
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 physical examination will include, at a minimum, head, ears, eyes, nose, mouth, 
skin, heart and lung examinations, lymph nodes, and gastrointestinal, musculoskeletal, and 
neurological systems. 
A brief physical examination will include, at a minimum, assessments of general appearance, 
the respiratory and cardiovascular systems, and participant-reported symptoms.
Physical examinations may be conducted by a physician, trained physician's assistant, or 
nurse practitioner as acceptable according to local regulation. 

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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. 
8.2.2. Neurological Examinations
Neurological examinations may be conducted by a physician, trained physician's assistant, or 
nurse practitioner as acceptable according to local regulation. The neurological exam will 
consist of assessment of higher cortical function, the cranial nerves, motor function, deep 
tendon reflexes, sensory exam, and coordination and gait. The exam should be done to the 
extent needed to assess the participant for any potential changes in neurological status, as 
determined by the investigator (or designee).
8.2.3. Vital Signs
Supine BP will be measured with the participant’s arm supported at the level of the heart, and 
recorded to the nearest mm Hg after approximately 5 minutes of rest.  The same arm 
(preferably the dominant arm) will be used throughout the study.  Participants should be 
instructed not to speak during measurements.  
The same properly sized and calibrated BP cuff will be used to measure BP each time.  The 
use of an automated device for measuring BP and pulse rate is acceptable; however, when 
done manually, pulse rate will be measured in the brachial/radial artery for at least 
30 seconds.  When the timing of these measurements coincides with a blood collection, BP 
and pulse rate should be obtained prior to the nominal time of the blood collection.
Additional collection times, or changes to collection times, of BP and pulse rate will be 
permitted, as necessary, to ensure appropriate collection of safety data.
The procedure for collecting postural or orthostatic data will be:

Assess BP after the participant is in the supine position for a minimum of 5 minutes;

Have the participant stand up for 2 minutes;

Assess BP after the participant is in the standing position for approximately 
2 minutes.
Orthostatic hypotension is defined as a decrease of ≥20 mm Hg for systolic BP or 
≥10 mm Hg for diastolic BP 2 minutes after standing from a supine position.  Orthostatic 
hypotension may be symptomatic or asymptomatic.  Symptoms of orthostatic hypotension 
are those that develop upon assuming the erect posture from a supine position and may 
include: lightheadedness, dizziness, blurred vision, weakness, fatigue, cognitive impairment, 
nausea, palpitations, tremulousness, headache, and/or neck ache.

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If a participant has symptoms suggestive of orthostasis, but not documented orthostatic 
hypotension, repeated measurements of supine/standing BP (triplicate supine/1 standing and 
further monitoring based on investigator/medical judgement) should be obtained. Lesser 
degrees of BP reduction may still be considered clinically significant if the participant 
becomes symptomatic upon standing, especially in the presence of a significant increase 
in pulse rate (≥30 beats per minute [bpm]).
8.2.4. Respiratory Rate
Respiratory rate will be measured at times specified in the SoA. After approximately 
5 minutes rest in supine position, respiratory rate will be measured by observing and 
counting the respirations of the subject for 30 seconds and multiplied by 2. When blood 
pressure is to be taken at the same time, respiration measurement will be done during the 
5 minutes of rest and before blood pressure measurement.
8.2.5. Oral Body Temperature
Body temperature will be measured orally. No eating or drinking is allowed for 15 minutes 
prior to the measurement.
8.2.6. 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 QTcF intervals and QRS 
complex. Alternative lead placement methodology using torso leads (eg, Mason-Likar) is not 
permitted 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 10 minutes in a supine position. 
Triplicate 12-lead ECGs will be obtained approximately 2 to 4 minutes apart; the average of 
the triplicate ECG measurements collected before dose administration on Day 1 of each 
period will serve as each participant’s baseline QTcF value. 
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) the 
mean value from the triplicate measurements for any postdose QTcF interval is increased by 
≥60 msec from the baseline and is >450 msec; or b) an absolute QTcF value is ≥500 msec
for any scheduled ECG.  If either of these conditions occurs, then a single ECG measurement 
must be repeated at least hourly until QTcF values from 2 successive ECGs fall below the 
threshold value that triggered the repeat measurement.

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If a) a postdose QTcF interval remains ≥60 msec from the baseline and is >450 msec; or 
b) an absolute QTcF 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 criterion 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 
QTcF 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.
8.2.6.1. Continuous Cardiac Monitoring by Telemetry
All abnormal rhythms will be recorded and reviewed by the study physician for the presence 
of rhythms of potential clinical concern.  The time, duration, and description of the clinically 
significant event will be recorded in the CRF.  In addition, a printed record of the tracing(s) 
of the clinically significant rhythm(s) will be made and retained with other source 
documents.
Telemetry should be collected using a centralized system that also allows for the storage and 
advanced analysis of all recorded data in order to preserve important events for future 
evaluations.  Holter monitoring should not be used in parallel with continuous telemetry, 
unless it is the only means of data storage available at the investigator site, or verifiable 
arrhythmia quantification is required.  To establish a baseline, telemetry should be recorded 
for at least 2 hours before dosing in Period 1.  This may be done immediately prior to dosing 
or at some 2-hour continuous interval in the 24 hours prior to dosing, as long as the recording 
is performed when the participant is awake.  Telemetry may be stopped within a reasonably 
short period of time prior to dosing, in order to avoid interference with study operations 
conducted immediately before dosing.  However, it is expected that the telemetry leads will 
be in place and the system connected prior to dosing.
8.2.7. 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.  

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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 14 days after the last dose of study intervention should be 
repeated until the values return to normal or baseline or are no longer considered clinically 
significant by the investigator or medical monitor.
If such values do not return to normal/baseline within a period of time judged reasonable by 
the investigator, the etiology should be identified and the sponsor notified.
See Appendix 6 for suggested actions and follow-up assessments in the event of potential 
drug-induced liver injury.
Participants may undergo random urine drug testing at the discretion of the investigator.  
Drug testing conducted prior to dosing must be negative for participants to receive study 
intervention. 
8.2.8. COVID-19 Specific Assessments
Participants will be tested for SARS-COVID-19 infection by PCR prior to being admitted to 
the clinic. Subsequent COVID-19 tests will be performed if they develop COVID-19 like 
symptoms. Additional testing may be required by local regulations or by the investigator.
8.3. Adverse Events and Serious Adverse Events
The definitions of an AE and an SAE can be found in Appendix 3.
AEs will be reported by the participant (or, when appropriate, by a caregiver, surrogate, or 
the participant's legally authorized representative).
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). 
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.

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8.3.1. Time Period and Frequency for Collecting AE and SAE Information
The time period for actively eliciting and collecting AEs and SAEs (“active collection 
period”) for each participant begins from the time the participant provides informed consent, 
which is obtained before the participant’s participation in the study (ie, before undergoing 
any study-related procedure and/or receiving study intervention), through and including a 
minimum of 28 calendar days, except as indicated below, after the last administration of the 
study intervention.
Follow-up by the investigator continues throughout and after the active collection period and 
until the AE or SAE or its sequelae resolve or stabilize at a level acceptable to the 
investigator and Pfizer concurs with that assessment.
For participants who are screen failures, the active collection period ends when screen failure 
status is determined.
If the participant withdraws from the study and also withdraws consent for the collection of 
future information, the active collection period ends when consent is withdrawn.
If a participant definitively 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 AE or SAE 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.

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8.3.2. Method of Detecting AEs and SAEs
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Appendix 3.
Care will be taken not to introduce bias when detecting AEs and/or SAEs.  Open-ended and 
nonleading verbal questioning of the participant is the preferred method to inquire about 
AE occurrences.
8.3.3. Follow-up of AEs and SAEs
After the initial AE/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 towards 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. Exposure During Pregnancy or Breastfeeding, and Occupational Exposure
Exposure to the study intervention under study during pregnancy or breastfeeding and 
occupational exposure are reportable to Pfizer Safety within 24 hours of investigator 
awareness.

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8.3.5.1. Exposure During Pregnancy
An EDP occurs if: 

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 exposure during pregnancy: 

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 at least 
28 days after the last dose of the study intervention.

If EDP occurs in the setting of environmental exposure, the investigator must report 
information to Pfizer Safety using the CT SAE Report Form and EDP Supplemental 
Form. Since the exposure information does not pertain to the participant enrolled in 
the study, the information is not recorded on a CRF; however, a copy of the 
completed CT SAE Report Form is maintained in the investigator site file.
Follow-up is conducted to obtain general information on the pregnancy and its outcome for 
all EDP reports with an unknown outcome. The investigator will follow the pregnancy until 
completion (or until pregnancy termination) and notify Pfizer Safety of the outcome as a 
follow-up to the initial EDP Supplemental Form. In the case of a live birth, the structural 
integrity of the neonate can be assessed at the time of birth. In the event of a termination, the 
reason(s) for termination should be specified and, if clinically possible, the structural 
integrity of the terminated fetus should be assessed by gross visual inspection (unless 
preprocedure test findings are conclusive for a congenital anomaly and the findings are 
reported).

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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 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 inhalation or skin contact.  
The investigator must report exposure during breastfeeding to Pfizer Safety within 24 hours 
of the investigator’s awareness, irrespective of whether an SAE has occurred.  The 
information must be reported using the CT SAE Report Form.  When exposure during 
breastfeeding occurs in the setting of environmental exposure, the exposure information does 
not pertain to the participant enrolled in the study, so the information is not recorded on a 
CRF. However, a copy of the completed CT SAE Report Form is maintained in the 
investigator site file.
An exposure during breastfeeding report is not created when a Pfizer drug specifically 
approved for use in breastfeeding women (eg, vitamins) is administered in accord with 
authorized use.  However, if the infant experiences an SAE associated with such a drug, the 
SAE is reported together with the exposure during breastfeeding.

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8.3.5.3. Occupational Exposure
An occupational exposure occurs when a person receives unplanned direct contact with the 
study intervention, which may or may not lead to the occurrence of an AE. Such persons 
may include healthcare providers, family members, and other roles that are involved in the 
trial participant’s care.
The investigator must report occupational exposure to Pfizer Safety within 24 hours of the 
investigator’s awareness regardless of whether there is an associated SAE.  The information 
must be reported using the CT SAE Report Form.  Since the information 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 is 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, at the wrong dosage strength, or 
inadvert exposure.
Exposures to the study intervention under study may occur in clinical trial settings, such as 
medication errors.
Safety Event
Recorded on the CRF
Reported on the CT SAE Report 
Form to Pfizer Safety Within 
24 Hours of Awareness
Medication errors 
All (regardless of whether 
associated with an AE)
Only if associated with an SAE

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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. Treatment of Overdose
 
The sponsor does not recommend specific treatment for an overdose.
In the event of an overdose, the investigator should:
1. Contact the medical monitor within 24 hours.
2. Closely monitor the participant for any AEs/SAEs and laboratory abnormalities for at 
least 5 half-lives or 28 calendar days after the overdose of PF-07258669 (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 Safety only when associated with an SAE.
5. Obtain a blood sample for PK analysis within 5 days 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.
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8.7. Genetics
8.7.1. Specified Genetics
Genetics (specified analyses) are not evaluated in this study.
8.7.2. Banked Biospecimens for Genetics
A 2-mL blood sample optimized for DNA isolation Prep D1.5 will be collected as local 
regulations and IRBs/ECs allow.
Banked Biospecimens may be used for research related to the study intervention(s).  Genes 
and other analytes (eg, proteins, RNA, nondrug metabolites) may be studied using the banked 
samples. 
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See Appendix 5 for information regarding genetic research.  Details on processes for 
collection and shipment of these samples can be found in the lab manual and other 
supporting documentation.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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8.8.2. Banked Biospecimens for Biomarkers
Additional Banked Biospecimens in this study are:

10-mL whole blood (Prep B2 optimized for serum).
Banked Biospecimens will be collected as local regulations and IRB/ECs allow. Banked 
Biospecimens may be used for research related to the study intervention(s) and safety 
biomarkers. Genes and other analytes (eg, proteins, RNA, nondrug metabolites) may be 
studied using the banked samples. See Appendix 5 for information regarding genetic 
research.  Details on processes for collection and shipment of these samples can be found in 
the lab manual and other supporting documentation. 
8.8.3. Specified Gene Expression (RNA) Research
Specified gene expression (RNA) research is not included in this study.
8.8.4. Specified Protein Research
Specified protein research is not included in this study.
8.8.5. Specified Metabolomic Research 
Specified metabolomic research is not included in this study.
8.9. Immunogenicity Assessments
Immunogenicity assessments are not included in this study.
8.10. Health Economics
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study.
9. STATISTICAL CONSIDERATIONS 
Detailed methodology for summary and statistical analyses of the data collected in this study 
is outlined here and further detailed in a 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
No formal hypothesis tests are planned for this study.

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9.2. Sample Size Determination
A sample size of up to approximately 8 participants per cohort (approximately 6 participants 
receiving PF-07258669 and up to 2 participants receiving placebo within each period) has 
been chosen based on the need to minimize first exposure to humans of a new chemical
entity and the requirement to provide adequate safety, tolerability, and PK assessment at each 
dose level. There are 2 planned cohorts and an additional optional third cohort which will 
only be used if the objectives of the study are not fulfilled in Cohort 1 and Cohort 2.
Participants who discontinue prior to completion of the study may be replaced, at the 
discretion of the investigator and sponsor.
9.3. 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, or their legally authorized 
representative’s, agreement to participate in a clinical study 
following completion of the informed consent process.  
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.
Evaluable
All participants randomly assigned to study intervention and 
who receive a dose of study intervention.
Safety
All participants randomly assigned to study intervention and 
who receive a dose of study intervention.  Participants will be 
analyzed according to the product they actually received.
PK Concentration 
All participants randomly assigned to study intervention and 
who receive a dose of study intervention and in whom at least 
1 plasma concentration value is reported.
PK Parameter 
All participants randomly assigned to study intervention and 
who receive a dose of study intervention and have at least 1 of 
the PK parameters of interest calculated.
9.4. 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.  Analysis of the tertiary/exploratory endpoints will be documented in the SAP.

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9.4.1. Safety Analyses
All safety analyses will be performed on the safety population.
AEs, ECGs, BP, pulse rate, respiratory rate, oral body temperature, continuous cardiac 
monitoring, 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, 
pulse rate, and respiratory rate 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, physical examination, 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 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. 
In addition, selected screening laboratory data may be reported.  
9.4.1.1. Electrocardiogram Interval Analyses
Changes from baseline for the ECG parameters (ie, QT interval, heart rate, QTcF interval, PR 
interval, and QRS complex) will be summarized by treatment and time.
The number (%) of participants with maximum postdose QTcF values and maximum 
increases from baseline in the following categories will be tabulated by treatment: 
Safety QTcF Assessment
Degree of Prolongation
Mild (msec)
Moderate (msec)
Severe (msec)
Absolute value
>450-480
>480-500
>500
Increase from baseline
30-60
>60
In addition, the number of participants with uncorrected QT values >500 msec will be 
summarized.
When more than 1 ECG is collected at a nominal time after dose administration (for example, 
triplicate ECGs), the mean of the replicate measurements will be used to represent a single 
observation at that time point.  If any of the 3 individual ECG tracings has a QTcF value 
>500 msec, but the mean of the triplicates is not >500 msec, the data from the participant’s 
individual tracing will be described in a safety section of the CSR in order to place the 
>500-msec value in appropriate clinical context.  However, values from individual tracings 
within triplicate measurements that are >500 msec will not be included in the categorical 
analysis unless the average from the triplicate measurements is also >500 msec.  Changes 

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from baseline will be defined as the change between the postdose QTcF value and the 
average of the predose triplicate values on Day 1.  
In addition, an attempt may be made to explore and characterize the relationship between 
plasma concentration and QT interval length using a PK/PD modeling approach.  If a PK/PD 
relationship is found, the impact of participant factors (covariates) on the relationship may be 
examined.  The results of such analyses will not be included in the CSR.
9.4.2. PK Analyses
The analysis populations are defined as in Section 9.3.
9.4.2.1. Derivation of PK Parameters
The PK parameters for PF-07258669, following oral dose administration, will be derived 
from the plasma concentration-time profiles as detailed in Table 2, as data permit. In all 
cases, actual PK sampling times will be used in the derivation of PK parameters.
Table 2.
Plasma PK Parameters
Parameter
Definition
Method of Determination
AUClast
Area under the plasma 
concentration-time profile from 
time 0 to the time of the last 
quantifiable concentration (Clast)
Linear/Log trapezoidal method
AUCinf*
Area under the plasma 
concentration-time profile from 
time 0 extrapolated to infinite time
AUClast + (Clast*/kel), where Clast* is the predicted 
plasma concentration at the last quantifiable 
timepoint estimated from the log-linear regression 
analysis
Cmax
Maximum observed concentration
Observed directly from data
Tmax
Time for Cmax
Observed directly from data as time of first 
occurrence
t1/2*
Terminal half-life
Loge(2)/kel, where kel is the terminal phase rate 
constant calculated by a linear regression of the 
log-linear concentration-time curve
•
Only those data points judged to describe the 
terminal log-linear decline will be used in the 
regression
 
*As data permit.
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9.4.2.2. Statistical Methods for PK Data
Plasma concentrations of PF-07258669 will be summarized descriptively by dose and 
nominal PK sampling time.  Individual participant and median profiles of the plasma 
concentration-time data will be plotted by dose using actual (for individual) and nominal (for 
median) times respectively.  Median profiles will be presented on both linear and log scales.  
The plasma PK parameters will be summarized descriptively by dose in accordance with 
Pfizer data standards, as data permit.  
 
 
 
Additional PK analyses may be performed if deemed appropriate, and may not be included in 
the CSR.
9.4.3. Other Analyses 
Pharmacogenomic or biomarker data from Banked Biospecimens may be collected during or 
after the trial and retained for future analyses; the results of such analyses are not planned to 
be included in the CSR.
9.5. Interim Analyses
No formal interim analysis will be conducted for this study. As this is a sponsor-open study,
a limited number of the sponsor’s team members (excluding site staff) may conduct 
unblinded reviews of the data during the course of the study for the purpose of safety and 
tolerability assessments, facilitating dose-escalation decisions, facilitating PK modeling, 
and/or supporting clinical development. 
9.6. Data Monitoring Committee or Other Independent Oversight Committee
This study will not use a DMC. 
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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 and 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.
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 guidelines, the IRB/EC, European regulation 536/2014 
for clinical studies (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.  
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 ICH GCP that the investigator becomes aware 
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10.1.2. Financial Disclosure
Investigators and subinvestigators will provide the sponsor with sufficient, accurate financial 
information as requested to allow the sponsor to submit complete and accurate financial 
certification or disclosure statements to the appropriate regulatory authorities. Investigators 
are responsible for providing information on financial interests during the course of the study 
and for 1 year after completion of the study.
10.1.3. Informed Consent Process
The investigator or his/her representative will explain the nature of the study 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, HIPAA 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 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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Unless prohibited by local requirements or IRB/EC decision, the ICD will contain a separate 
section that addresses the use of samples for optional additional research.  The optional
additional research does not require the collection of any further samples. The investigator 
or authorized designee will explain to each participant the objectives of the additional
research. Participants will be told that they are free to refuse to participate and may 
withdraw their consent at any time and for any reason during the storage period. A separate 
signature will be required to document a participant's agreement to allow specimens to be 
used for additional research. Participants who decline to participate in this optional
additional research will not provide this separate signature.
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 identification. 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. 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 
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www.clinicaltrials.gov
Pfizer posts clinical trial results on www.clinicaltrials.gov for Pfizer-sponsored interventional 
studies (conducted in patients) that evaluate the safety and/or efficacy of a product,
regardless of the geographical location in which the study is conducted.  These results are 
submitted for posting in accordance with the format and timelines set forth by US law.
EudraCT
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 available data from these trials 
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.

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10.1.6. Data Quality Assurance
All participant data relating to the study will be recorded on printed or electronic CRF unless 
transmitted to the sponsor or designee electronically (eg, laboratory data). The investigator is 
responsible for verifying that data entries are accurate and correct by physically or 
electronically signing the CRF.
The investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF.
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 (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, remote, or on-site monitoring), are provided in the IQMP.
The sponsor or designee is responsible for the data management of this study, including 
quality checking of the data.
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, and all applicable regulatory requirements.
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.

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The investigator(s) will notify the sponsor or its agents immediately of any regulatory 
inspection notification in relation to the study.  Furthermore, the investigator will cooperate 
with the sponsor or its agents to prepare the investigator site for the inspection and will allow 
the sponsor or its agent, whenever feasible, to be present during the inspection.  The 
investigator site and investigator will promptly resolve any discrepancies that are identified 
between the study data and the participant's medical records.  The investigator will promptly 
provide copies of the inspection findings to the sponsor or its agent.  Before response 
submission to the regulatory authorities, the investigator will provide the sponsor or its 
agents with an opportunity to review and comment on responses to any such findings.
10.1.7. Source Documents
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected.  Source documents are filed at the investigator site.
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 can be found in the Source Document Locator.
Description of the use of computerized system is documented in the Source Document 
Locator.
10.1.8. Study and Site Start and Closure
The study start date is the date on which the clinical study will be open for recruitment of 
participants.
The first act of recruitment is the date of the first participant’s first visit and will be the study 
start date.
The sponsor designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of the sponsor. Study sites will be closed upon 
study completion. A study site is considered closed when all required documents and study 
supplies have been collected and a study-site closure visit has been performed.
The investigator may initiate study-site closure at any time upon notification to the sponsor if 
requested to do so by the responsible IRB/EC or if such termination is required to protect the 
health of study participants.
Reasons for the early closure of a study site by the sponsor may include but are not limited 
to:

Failure of the investigator to comply with the protocol, the requirements of the 
IRB/EC or local health authorities, the sponsor's procedures, or GCP guidelines;

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
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.
10.1.9. Publication Policy
The results of this study may be published or presented at scientific meetings by the 
investigator after publication of the overall study results or 1 year after the end of the study 
(or study termination), whichever comes first. 
The investigator agrees to refer to the primary publication in any subsequent publications 
such as secondary manuscripts, and submits all manuscripts or abstracts to the sponsor 
30 days before submission. This allows the sponsor to protect proprietary information and to 
provide comments and the investigator will, on request, remove any previously undisclosed 
confidential information before disclosure, except for any study- or Pfizer-intervention 
related information necessary for the appropriate scientific presentation or understanding of 
the study results.
For all publications relating to the study, the investigator will comply with recognized ethical 
standards concerning publications and authorship, including those established by the 
International Committee of Medical Journal Editors.
The sponsor will comply with the requirements for publication of the overall study results 
covering all investigator sites.  In accordance with standard editorial and ethical practice, the 
sponsor will support publication of multicenter studies only in their entirety and not as 
individual site data.  In this case, a coordinating investigator will be designated by mutual 
agreement.
Authorship of publications for the overall study results will be determined by mutual 
agreement and in line with International Committee of Medical Journal Editors authorship
requirements. 
If publication is addressed in the clinical study agreement, the publication policy set out in 
this section will not apply.

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10.1.10. Sponsor’s Qualified Medical Personnel
The contact information for the sponsor's appropriately qualified medical personnel for the 
study is documented in the study contact list located in the CTMS. 
To facilitate access to appropriately qualified medical personnel on study-related medical 
questions or problems, participants are provided with a contact card at the time of informed 
consent.  The contact card contains, at a minimum, protocol and study intervention
identifiers, participant numbers, contact information for the investigator site, and contact 
details for a contact center in the event that the investigator site staff cannot be reached to 
provide advice on a medical question or problem originating from another healthcare 
professional not involved in the participant’s participation in the study.  The contact number 
can also be used by investigator staff if they are seeking advice on medical questions or 
problems; however, it should be used only in the event that the established communication 
pathways between the investigator site and the study team are not available.  It is therefore 
intended to augment, but not replace, the established communication pathways between the 
investigator site and the study team for advice on medical questions or problems that may 
arise during the study.  For sites other than a Pfizer CRU, the contact number is not intended 
for use by the participant directly, and if a participant calls that number, he or she will be 
directed back to the investigator site.

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10.2. Appendix 2: Clinical Laboratory Tests
The following safety laboratory tests will be performed at times defined in the SoA section of 
this protocol. Additional laboratory results may be reported on these samples as a result of 
the method of analysis or the type of analyzer used by the clinical laboratory, or as derived 
from calculated values. These additional tests would not require additional collection of 
blood. Unscheduled clinical laboratory measurements may be obtained at any time during 
the study to assess any perceived safety issues.
Table 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 (urea) and 
creatinine
eGFR (CKD-EPI)
Glucose (fasting)
Calcium
Sodium
Potassium
Chloride
Total CO2 (bicarbonate)
AST, ALT
Total bilirubin
Alkaline phosphatase
Uric acid
Albumin
Total protein
Lipid panel:
• Total cholesterol 
• Triglycerides
• HDL
• LDL (calculated)
pH
Glucose (qual)
Protein (qual)
Blood (qual)
Ketones
Nitrites
Leukocyte esterase
Urobilinogen
Urine bilirubin
Microscopya
• Urine drug screeningb
• COVID-19 testing
At screening only:
• FSHc
• Hepatitis B surface antigen
• Hepatitis B surface 
antibody
• Hepatitis B core antibody
• Hepatitis C antibody
• Human immunodeficiency 
virus
a.
Only if urine dipstick is positive for blood, protein, nitrites, or leukocyte esterase.
b.
The minimum requirement for drug screening includes cocaine, THC, opiates/opioids, benzodiazepines, 
and amphetamines (others are site and study specific).
c.
For confirmation of postmenopausal status only.
Investigators must document their review of each laboratory safety report.
Laboratory/analyte results that could unblind the study will not be reported to investigator
sites or other blinded personnel until the study has been unblinded.
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. 
 
 
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 conditions 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/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 which 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 SAE
If an event is not an AE per definition above, then it cannot be an SAE even if serious 
conditions are met (eg, hospitalization for signs/symptoms of the disease under study, death 
due to progression of disease).
An SAE is defined as any untoward medical occurrence that, at any dose:
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 detained (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 

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baseline is not considered an AE.
d. Results in persistent 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) which may interfere with or 
prevent everyday life functions but do not constitute a substantial disruption.
e.
Is a congenital anomaly/birth defect
f.
Other situations:

Medical or scientific judgment should be exercised in deciding whether SAE 
reporting is appropriate in other situations such as important medical events that 
may not be immediately life-threatening or result in death or hospitalization but 
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.

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 patient 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.

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10.3.3. Recording/Reporting and Follow-up of AEs and/or SAEs
AE and SAE Recording/Reporting
The table below summarizes the requirements for recording adverse events on the CRF and 
for reporting serious adverse events on the CT SAE Report Form to Pfizer Safety.  These 
requirements are delineated for 3 types of events: (1) SAEs; (2) nonserious AEs; and
(3) exposure to the study intervention under study during pregnancy or breastfeeding, and 
occupational exposure. 
It should be noted that the CT SAE Report Form for reporting of SAE information is not 
the same as the AE page of the CRF.  When the same data are collected, the forms must be 
completed in a consistent manner.  AEs should be recorded using concise medical 
terminology and the same AE term should be used on both the CRF and the CT SAE 
Report Form for reporting of SAE information.
Safety Event
Recorded on the CRF
Reported on the CT SAE 
Report Form to Pfizer 
Safety Within 24 Hours of 
Awareness
SAE
All
All
Nonserious AE
All
None
Exposure to the study 
intervention under study 
during pregnancy or 
breastfeeding, and 
occupational exposure
All AEs/SAEs associated 
with exposure during 
pregnancy or breastfeeding.
Occupational exposure is 
not recorded.
All (and EDP supplemental 
form for EDP)  
Note: Include all SAEs 
associated with exposure 
during pregnancy or
breastfeeding. Include all 
AEs/SAEs associated with 
occupational exposure.

When an AE/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/SAE information in the CRF.

It is not acceptable for the investigator to send photocopies of the participant’s 
medical records to Pfizer Safety in lieu of completion of the CT SAE Report 
Form/AE/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 

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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/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: An event that is easily tolerated by the participant, causing minimal 
discomfort and not interfering with everyday activities.

Moderate: An event that causes sufficient discomfort and interferes with normal 
everyday activities.

Severe: An event that prevents normal everyday activities. An AE that is assessed
as severe should not be confused with an SAE.  Severe is a category utilized for 
rating the intensity of an event; and both AEs and SAEs can be assessed as severe.
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/SAE.

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.

The investigator will use clinical judgment to determine the relationship.

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/SAE, the investigator must document in the medical notes that he/she
has reviewed the AE/SAE and has provided an assessment of causality.

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
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.

New or updated information will be recorded in the originally completed CRF.

The investigator will submit any updated SAE data to the sponsor within 24 hours 
of receipt of the information.

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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) in order 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 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 a male condom when engaging in any activity that allows for 
passage of ejaculate to another person.

In addition to male condom use, a highly effective method of contraception is 
recommended for 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 a WOCBP (see definitions below in 
Section 10.4.3. 
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;

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
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. 

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.
10.4.4. Contraception Methods
The following contraception methods are to be used by women of childbearing potential who 
are partners of male participants in this study:
Highly Effective Methods That Have Low User Dependency 
1. Implantable progestogen-only hormone contraception associated with inhibition of 
ovulation.
2. Intrauterine device.
3. Intrauterine hormone-releasing system.
4. Bilateral tubal occlusion.
5. Vasectomized partner.

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
Vasectomized partner is a highly effective contraceptive method provided that the 
partner is the sole sexual partner of the WOCBP and the absence of sperm has 
been confirmed.  If not, an additional highly effective method of contraception 
should be used.  The spermatogenesis cycle is approximately 90 days.
6. Combined (estrogen- and progestogen-containing) hormonal contraception associated 
with inhibition of ovulation.

Oral;

Intravaginal;

Transdermal;

Injectable.
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.
One of the following effective barrier methods must be used in addition to the highly 
effective methods listed above that are user dependent:

Male or female condom with or without spermicide;

Cervical cap, diaphragm, or sponge with spermicide;

A combination of male condom with either cervical cap, diaphragm, or sponge with 
spermicide (double-barrier methods).

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10.5. Appendix 5: Genetics
Use/Analysis of DNA

Genetic variation may impact a participant’s response to study intervention, 
susceptibility to, and severity and progression of disease. Therefore, where local 
regulations and IRBs/ECs allow, a blood sample will be collected for DNA analysis.

The scope of the genetic research may be narrow ((eg, 1 or more candidate genes) or
broad (eg, the entire genome), as appropriate to the scientific question under 
investigation.

The samples may be analyzed as part of a multistudy assessment of genetic factors 
involved in the response to PF-07258669/placebo or study interventions of this class 
to understand treatments for the disease(s) under study or the disease(s) themselves.

The results of genetic analyses may be reported in the CSR or in a separate study 
summary, or may be used for internal decision making without being included in a 
study report.

The sponsor will store the DNA samples in a secure storage space with adequate 
measures to protect confidentiality. 

The samples will be retained as indicated:

Samples for banking will be stored indefinitely or for another period as per local 
requirements.  

Participants may withdraw their consent for the storage and/or use of their Banked 
Biospecimens at any time by making a request to the investigator; in this case, any 
remaining material will be destroyed.  Data already generated from the samples will 
be retained to protect the integrity of existing analyses.  

Banked Biospecimens will be labeled with a code.  The key between the code and the 
participant’s personally identifying information (eg, name, address) will be held at the 
study site and will not be provided to the sample bank.

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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, commonly referred to as DILI.  
Participants who experience a transaminase elevation above 3 × ULN should be monitored 
more frequently to determine if they are an “adaptor” or are “susceptible.”
In the majority of DILI cases, elevations in AST and/or ALT precede TBili elevations 
(>2 × ULN) by several days or weeks.  The increase in TBili typically occurs while 
AST/ALT is/are still elevated above 3 × ULN (ie, AST/ALT and TBili values will be 
elevated within the same laboratory sample).  In rare instances, by the time TBili elevations 
are detected, AST/ALT values might have decreased.  This occurrence is still regarded as a 
potential DILI.  Therefore, abnormal elevations in either AST OR ALT in addition to TBili 
that meet the criteria outlined below are considered potential DILI (assessed per Hy’s law 
criteria) cases and should always be considered important medical events, even before all 
other possible causes of liver injury have been excluded.
The threshold of laboratory abnormalities for a potential DILI case depends on the 
participant’s individual baseline values and underlying conditions.  Participants who present 
with the following laboratory abnormalities should be evaluated further as potential DILI 
(Hy’s law) cases to definitively determine the etiology of the abnormal laboratory values:

Participants with AST/ALT and TBili baseline values within the normal range who 
subsequently present with AST OR ALT values >3 × ULN AND a TBili value 
>2 × ULN with no evidence of hemolysis and an alkaline phosphatase value
<2 × ULN or not available.

For participants with baseline AST OR ALT OR TBili values above the ULN, the 
following threshold values are used in the definition mentioned above, as needed, 
depending on which values are above the ULN at baseline:

Preexisting AST or ALT baseline values above the normal range: AST or ALT 
values >2 times the baseline values AND >3 × ULN; or >8 × ULN (whichever is 
smaller).

Preexisting values of TBili above the normal range: TBili level increased from 
baseline value by an amount of at least 1 × ULN or if the value reaches 
>3 × ULN (whichever is smaller).

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Rises in AST/ALT and TBili separated by more than a few weeks should be assessed 
individually based on clinical judgment; any case where uncertainty remains as to whether it 
represents a potential Hy’s law case should be reviewed with the sponsor.
The participant should return to the investigator site and be evaluated 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 cases of 
Hy’s law, 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, 
supplement (herbal) use and consumption, family history, sexual history, travel history, 
history of contact with a jaundiced person, surgery, blood transfusion, history of liver or 
allergic disease, and potential occupational exposure to chemicals, should be collected.  
Further testing for acute hepatitis A, B, C, D, and E infection and 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 LFT abnormalities has yet been found.  Such potential DILI (Hy’s law) 
cases are to be reported as SAEs, irrespective of availability of all the results of the 
investigations performed to determine etiology of the LFT abnormalities.
A potential DILI (Hy’s law) case becomes a confirmed case only after all results of
reasonable investigations have been received and have excluded an alternative etiology.

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10.7. Appendix 7: 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).

Ventricular rhythms >30 seconds’ duration, including idioventricular rhythm (heart 
rate <40 bpm), accelerated idioventricular rhythm (HR >40 bpm to <100 bpm), and 

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

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10.10. Appendix 10: Abbreviations
The following is a list of abbreviations that may be used in the protocol.
Abbreviation
Term
Abs
absolute
AE
adverse event
ALP
alkaline phosphatase
ALT
alanine aminotransferase
AST
aspartate aminotransferase
AUC
area under the curve
AUC24
area under the curve from time=0 to time=24 hours post dose
AUClast
area under the plasma concentration-time profile from time 0 to the 
time of the last quantifiable concentration
AUCinf
area under the plasma concentration-time profile from time 0 
extrapolated to infinite time
AV
atrioventricular
β-hCG
beta-human chorionic gonadotropin
BMI
body mass index
BP
blood pressure
bpm
beats per minute
BUN
blood urea nitrogen
Ceff
efficacious concentration
CFR
Code of Federal Regulations
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
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Abbreviation
Term
CSR
clinical study report
CT
clinical trial
CTMS
clinical trial management system
DC
discontinuation
DILI
drug-induced liver injury
DMC
data monitoring committee
EC
ethics committee
ECG
electrocardiogram
eCRF
electronic case report form
EDP
exposure during pregnancy
EDR
extemporaneous dispensing record
eGFR
estimated glomerular filtration rate
EMA
European Medicines Agency
ET
early termination
EU
European Union
EudraCT
European Clinical Trials Database
FSH
follicle-stimulating hormone
GCP
Good Clinical Practice
GGT
gamma-glutamyl transferase
GLP
Good Laboratory Practice
GPCR
G-protein coupled receptor
HBcAb
hepatitis B core antibody
HBsAb
hepatitis B surface antibody
HBsAg 
hepatitis B surface antigen
HCVAb
hepatitis C antibody
HDL
high-density lipoprotein
HIPAA
Health Insurance Portability and Accountability Act
HIV
human immunodeficiency virus
HR
heart rate
HRT
hormone replacement therapy
IB
investigator’s brochure
ICD
informed consent document
ICH
International Council for Harmonisation
ID
identification
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Abbreviation
Term
IND
investigational new drug 
INR
international normalized ratio
IPAL
Investigational Product Accountability Log
IQMP
integrated quality management plan
IRB
institutional review board
IV
intravenous
kel
elimination rate constant
LBBB
left bundle branch block
LFT
liver function test
LDL
low-density lipoprotein
MC1R
melanocortin-1 receptor
MC2R
melanocortin-2 receptor
MC3R
melanocortin-3 receptor
MC4R
melanocortin-4 receptor
MC5R
melanocortin-5 receptor
MCH
mean corpuscular hemoglobin
MCHC
mean corpuscular hemoglobin concentration
MCV
mean corpuscular volume
msec
millisecond
N/A
not applicable
NOAEL
no-observed-adverse-effect level
NOEL
no-observed-effect-level
PCR
polymerase chain reaction
PCRU
Pfizer clinical research unit
PD
pharmacodynamic(s)
PI
principal investigator
PIMS
Phase 1 Management System
PK
pharmacokinetic(s)
PR
pulse rate
PT
prothrombin time
PVC
premature ventricular contraction/complex
QTc
corrected QT
QTcF
corrected QT (Fridericia method)
RBC
red blood cell
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Abbreviation
Term
SAE
serious adverse event
SAP
statistical analysis plan
SCr
serum creatinine
SoA
schedule of activities
SOP
standard operating procedure
SPF
sun protection factor
SRSD
single reference safety document
SUSAR
suspected unexpected serious adverse reaction
t½
terminal half-life
TBili
total bilirubin
THC
tetrahydrocannabinol
Tmax
time for Cmax
ULN
upper limit of normal
US
United States
UV
ultraviolet
WBC
white blood cell
WOCBP
woman of childbearing potential
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11. REFERENCES
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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