A 2 COHORT, SINGLE DOSE, OPEN-LABEL, RANDOMIZED, PIVOTAL BIOEQUIVALENCE STUDY TO QUALIFY MANUFACTURING SITE TRANSFER FROM BARCELONETA TO ASCOLI FOR PRAZOSIN HYDROCHLORIDE CAPSULES IN HEALTHY ADULT PARTICIPANTS UNDER FASTED CONDITIONS
Phase: PHASE1
Conditions: Hypertension, Heart Failure
Sponsor: Pfizer

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A 2 COHORT, SINGLE DOSE, OPEN-LABEL, RANDOMIZED, PIVOTAL 
BIOEQUIVALENCE STUDY TO QUALIFY MANUFACTURING SITE TRANSFER 
FROM BARCELONETA TO ASCOLI FOR PRAZOSIN HYDROCHLORIDE 
CAPSULES IN HEALTHY ADULT PARTICIPANTS UNDER FASTED 
CONDITIONS
Study Intervention Number:
CP-012299
Study Intervention Name:
Prazosin Hydrochloride Capsules
US IND Number:
EudraCT Number:
ClinicalTrials.gov ID:
Not Applicable
Protocol Number:
A0281006
Phase:
1
Brief Title: Pivotal Bioequivalence Study to Qualify Manufacturing Site Transfer of Prazosin 
Hydrochloride Capsules
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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Document History
Document
Version Date
Summary of Changes and 
Rationale
Original protocol
22 February 2021
Not Applicable

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TABLE OF CONTENTS
LIST OF TABLES.....................................................................................................................7
1. PROTOCOL SUMMARY.....................................................................................................8
1.1. Synopsis ....................................................................................................................8
1.2. Schema (Not Applicable)........................................................................................12
1.3. Schedule of Activities .............................................................................................13
2. INTRODUCTION ...............................................................................................................16
2.2. Background .............................................................................................................16
2.2.1. Clinical Overview.......................................................................................16
2.3. Benefit/Risk Assessment.........................................................................................17
2.3.1. Risk Assessment.........................................................................................18
2.3.2. Overall Benefit/Risk Conclusion................................................................19
3. OBJECTIVES AND ENDPOINTS.....................................................................................19
4. STUDY DESIGN.................................................................................................................19
4.1. Overall Design.........................................................................................................19
4.2. Scientific Rationale for Study Design.....................................................................21
4.2.1. Choice of Contraception/Barrier Requirements .........................................21
4.2.2. Collection of Retained Research Samples..................................................21
4.4. End of Study Definition ..........................................................................................22
5. STUDY POPULATION......................................................................................................22
5.1. Inclusion Criteria.....................................................................................................23
5.2. Exclusion Criteria....................................................................................................23
5.3. Lifestyle Considerations..........................................................................................25
5.3.1. Meals and Dietary Restrictions...................................................................25
5.3.2. Caffeine, Alcohol, and Tobacco .................................................................26
5.3.3. Activity .......................................................................................................26
5.3.4. Contraception..............................................................................................27
5.4. Screen Failures ........................................................................................................27
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY.................................27
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6.1. Study Intervention(s) Administered........................................................................27
6.1.1. Administration............................................................................................27
6.2. Preparation, Handling, Storage, and Accountability...............................................28
6.2.1. Preparation and Dispensing........................................................................29
6.3. Measures to Minimize Bias: Randomization and Blinding.....................................29
6.3.1. Allocation to Study Intervention ................................................................29
6.4. Study Intervention Compliance...............................................................................29
6.5. Dose Modification...................................................................................................30
6.6. Continued Access to Study Intervention After the End of the Study......................30
6.7. Treatment of Overdose............................................................................................30
6.8. Concomitant Therapy..............................................................................................30
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL...........................................................................31
7.1. Discontinuation of Study Intervention ....................................................................31
7.2. Participant Discontinuation/Withdrawal From the Study.......................................31
7.2.1. Withdrawal of Consent...............................................................................32
7.3. Lost to Follow up ....................................................................................................32
8. STUDY ASSESSMENTS AND PROCEDURES...............................................................33
8.1. Efficacy Assessments..............................................................................................34
8.2. Safety Assessments .................................................................................................34
8.2.1. Physical Examinations................................................................................34
8.2.2. Vital Signs ..................................................................................................35
8.2.3. Electrocardiograms.....................................................................................35
8.2.4. Clinical Safety Laboratory Assessments ....................................................36
8.2.5. COVID-19 specific assessments.................................................................36
8.2.6. Pregnancy Testing ......................................................................................37
8.3. Adverse Events, Serious Adverse Events, and Other Safety Reporting .................37
8.3.1. Time Period and Frequency for Collecting AE and SAE Information.......37
8.3.1.1. Reporting SAEs to Pfizer Safety...............................................38
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF...................38
8.3.2. Method of Detecting AEs and SAEs ..........................................................38
8.3.3. Follow-Up of AEs and SAEs......................................................................38

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8.3.4. Regulatory Reporting Requirements for SAEs...........................................39
8.3.5. Environmental Exposure, Exposure During Pregnancy or 
Breastfeeding, and Occupational Exposure.....................................................39
8.3.5.1. Exposure During Pregnancy......................................................39
8.3.5.2. Exposure During Breastfeeding ................................................41
8.3.5.3. Occupational Exposure .............................................................41
8.3.6. Cardiovascular and Death Events...............................................................42
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs..............................................................................42
8.3.8. Adverse Events of Special Interest.............................................................42
8.3.8.1. Lack of Efficacy........................................................................42
8.3.9. Medical Device Deficiencies......................................................................42
8.3.10. Medication Errors.....................................................................................42
8.4. Pharmacokinetics ....................................................................................................43
8.5. Genetics...................................................................................................................44
8.5.1. Specified Genetics ......................................................................................44
8.5.2. Retained Research Samples for Genetics ...................................................44
8.6. Biomarkers ..............................................................................................................44
8.7. Immunogenicity Assessments.................................................................................44
8.8. Health Economics ...................................................................................................44
9. STATISTICAL CONSIDERATIONS ................................................................................44
9.1. Statistical Hypotheses .............................................................................................44
9.2. Analysis Sets ...........................................................................................................45
9.3. Statistical Analyses .................................................................................................45
9.3.1. Primary Endpoint(s)....................................................................................45
9.3.1.1. Determination of Pharmacokinetic Parameters.........................45
9.3.2. Statistical Analysis of Pharmacokinetic Parameter ....................................46
9.3.3. Safety analyses............................................................................................47
9.3.4. Other Analyse(s).........................................................................................47
9.4. Interim Analyses .....................................................................................................48
9.5. Sample Size Determination.....................................................................................48

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10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS..........................................................................................................49
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations...............49
10.1.1. Regulatory and Ethical Considerations ....................................................49
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP.........................................................................49
10.1.2. Financial Disclosure .................................................................................50
10.1.3. Informed Consent Process ........................................................................50
10.1.4. Data Protection .........................................................................................51
10.1.5. Committees Structure ...............................................................................51
10.1.5.1. Data Monitoring Committee ...................................................51
10.1.6. Dissemination of Clinical Study Data ......................................................51
10.1.7. Data Quality Assurance ............................................................................53
10.1.8. Source Documents....................................................................................54
10.1.9. Study and Site Start and Closure ..............................................................54
10.1.10. Publication Policy...................................................................................55
10.1.11. Sponsor’s Qualified Medical Personnel .................................................56
10.2. Appendix 2: Clinical Laboratory Tests .................................................................57
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting .....................................................................58
10.3.1. Definition of AE .......................................................................................58
10.3.2. Definition of an SAE ................................................................................59
10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During 
the Active Collection Period............................................................................60
10.3.4. Reporting of SAEs....................................................................................64
10.4. Appendix 4: Contraceptive and Barrier Guidance ................................................65
10.4.1. Male Participant Reproductive Inclusion Criteria....................................65
10.4.2. Female Participant Reproductive Inclusion Criteria.................................65
10.4.3. Woman of Childbearing Potential ............................................................66
10.4.4. Contraception Methods.............................................................................67
10.5. Appendix 5: Genetics............................................................................................69
10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments .......70
10.7. Appendix 7: ECG Findings of Potential Clinical Concern ...................................72

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10.8. Appendix 8: Alternative Measures During Public Emergencies ..........................74
10.8.1. Study Intervention ....................................................................................74
10.8.2. Adverse Events and Serious Adverse Events...........................................74
10.10. Appendix 9: Abbreviations .................................................................................75
11. REFERENCES ..................................................................................................................78
LIST OF TABLES
Table 1.
Schedule of Activities...............................................................................13
Table 2.
Sequences for Cohort 1.............................................................................20
Table 3.
Sequences for Cohort 2.............................................................................20
Table 4.
Composition of 1 mg , 2 mg, and 5 mg Prazosin HCl Capsules 
Manufactured at Ascoli.............................................................................21
Table 5.
PK Parameters ..........................................................................................46
Table 6.
Protocol-Required Safety Laboratory Assessments .................................57

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1. PROTOCOL SUMMARY 
1.1. Synopsis 
Brief Title: Pivotal Bioequivalence Study to Qualify Manufacturing Site Transfer for 
Prazosin Hydrochloride Capsules.
Background and Rationale:
 
Prazosin is a selective 
α-adrenoreceptor antagonist and is used either as single drug or combination treatment with 
diuretic and/or other antihypertensive drugs for proper patient response.
 
 
 
 
 
 
 
 
 
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Objectives and Endpoints
Objectives
Endpoints
Primary: 
Primary: 

To demonstrate bioequivalence between 
prazosin HCl 1 and 2 mg capsules 
manufactured at the proposed site (Ascoli) 
versus prazosin HCl 2 mg capsules 
manufactured at current site (Barceloneta) 
under fasting conditions in healthy adult 
participants. 

To demonstrate bioequivalence between 
prazosin HCl 5 mg capsules manufactured at 
the proposed site (Ascoli) versus prazosin HCl
5 mg capsules manufactured at current site 
(Barceloneta) under fasting conditions in 
healthy adult participants.

AUClast and Cmax of prazosin.
Secondary: 
Secondary: 

To evaluate the safety and tolerability of 
prazosin HCl capsules.

AUCinf (if data permit), t½ (if data permit) and 
Tmax of prazosin.

Adverse events (AEs).

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Overall Design
This study will be a 2 Cohort, open-label, randomized, single dose study in healthy adult 
male and/or female participants. Cohort 1 will be crossover with 3 treatments, 3 periods, 
6 sequences. Cohort 2 will be crossover with 2 treatments, 2 periods, 2 sequences.
Approximately 36 participants will be enrolled in each Cohort 1 and Cohort 2. Participants 
enrolled in Cohort 1 will not be eligible for Cohort 2 and vice versa. Dropouts for non-safety 
reasons may be replaced at the discretion of the sponsor and investigator. Participants in 
Cohort 1 will be assigned to 1 of the 6 sequences according to a computer--generated 
randomization schedule and participants in Cohort 2 will be assigned to 1 of the 2 sequences 
according to a computer-generated randomization schedule. The sequences for Cohort 1 and 
Cohort 2 are shown in the tables below.
Sequences for Cohort 1
Sequence
N
Period 1
Washout 
Period
Period 2
Washout 
Period
Period 3
1
6
Treatment A
At least
7 days
Treatment B
At least
7 days
Treatment C
2
6
Treatment B
Treatment C
Treatment A
3
6
Treatment C
Treatment A
Treatment B
4
6
Treatment A
Treatment C
Treatment B
5
6
Treatment B
Treatment A
Treatment C
6
6
Treatment C
Treatment B
Treatment A
Treatment A: Prazosin HCl 1 x 2 mg capsule manufactured at the current site (Barceloneta) under fasting 
conditions (Reference).
Treatment B: Prazosin HCl 1 x 2 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test1).
Treatment C: Prazosin HCl 2 x 1 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test2).
Sequences for Cohort 2
Sequence
N
Period 1
Washout Period
Period 2
1
18
Treatment D
At least 7 days
Treatment E
2
18
Treatment E
Treatment D
Treatment D: Prazosin HCl 1 x 5 mg capsule manufactured at the current site (Barceloneta) under fasting 
conditions (Reference).
Treatment E: Prazosin HCl 1 x 5 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test).
Number of Participants
Approximately 36 participants will be enrolled in each Cohort 1 and Cohort 2 such that 30 
evaluable participants complete Cohort 1 and 32 evaluable participants complete Cohort 2.
See the Section 9.5 Sample Size Determination for further details. 

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Intervention Groups and Duration
Participants will be screened within 28 days prior to the first dose of study intervention to 
confirm that they meet the participant selection criteria for the study. Eligible participants 
will be admitted to the clinical research unit (CRU) on Day -1 and will remain confined in 
the CRU for approximately 3 days and 2 nights during each period until the collection of the 
24 hour pharmacokinetic (PK) sample.
On Day 1 of each period, participants will receive a single dose of investigational product as 
per randomization schedule. Study treatments will be administered with approximately 240 
mL of ambient temperature water under fasting conditions (overnight fast and no food until 4 
hours after dosing). Water will be allowed without restriction until 1 hour prior to dosing and
may be consumed without restriction beginning 1 hour after dosing.
Blood samples for the analysis of prazosin in plasma will be obtained predose (immediately 
prior to dosing) and postdose. Tolerability and safety will be assessed for all treatments by 
monitoring adverse events (AEs).
There will be a minimum 7-day washout period between successive doses (ie, administration 
of subsequent doses of study medication will not occur until at least 7 days after the previous 
dose of study medication). The total duration of participation from the Screening Visit to 
Discharge will be approximately 6 weeks, and from the Screening Visit to Follow-up will be 
approximately 11 weeks.
Study Treatments
For this study, the investigational product is prazosin HCl capsules.
Prazosin HCl 2 mg and 5 mg capsules, manufactured at Pfizer Pharmaceutical, Barceloneta 
Puerto Rico are reference treatments. Prazosin HCl 1 mg, 2 mg and 5 mg capsules, 
manufactured at Pfizer Pharmaceutical, Ascoli, Italy are test treatments. 
Data Monitoring Committee or Other Independent Oversight Committee: No
This study will not use a data monitoring committee (DMC).
Statistical Methods
Pharmacokinetic and statistical analysis will be performed for prazosin. Data from 2 Cohorts 
will be analyzed separately. The PK parameters area under the plasma concentration-time 
curve from time zero to the time of the last quantifiable concentration (AUClast), area under 
the plasma concentration-time curve from time zero extrapolated to infinite time (AUCinf), 
maximum plasma concentration (Cmax), time to first occurrence of Cmax (Tmax), and terminal 
phase elimination half-life (t½) will be summarized descriptively by analyte and treatment.

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Natural log transformed PK parameters (AUCinf, AUClast, and Cmax) will be analyzed using a 
mixed effect model with sequence, period and treatment as fixed effects and participant 
within sequence as a random effect. Estimates of the adjusted mean differences 
(Test – Reference) and the corresponding 90% confidence intervals will be obtained from the 
model. The adjusted mean differences and the 90% confidence intervals for the differences 
will be exponentiated to provide estimates of the ratio of adjusted geometric means 
(Test/Reference) and the 90% confidence intervals for the ratios.
For primary objective, bioequivalence of the Test treatment relative to Reference treatment 
will be concluded if the 90% confidence intervals (CI) for the ratio of adjusted geometric 
means of Test treatments relative to Reference treatment for AUCinf (if data permit), AUClast
and Cmax, fall wholly within (80%, 125%).
1.2. Schema (Not Applicable)

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1.3. Schedule of Activities
The SoA table (Table 1) provides an overview of the protocol visits and procedures. Refer to the STUDY ASSESSMENTS AND 
PROCEDURES section of the protocol for detailed information on each procedure and assessment required for compliance with the 
protocol. 
The investigator may schedule visits (unplanned visits) in addition to those listed in the SoA table, in order to conduct evaluations or 
assessments required to protect the well-being of the participant. 
Table 1.
Schedule of Activities
Visit Identifier
Screening 
(Day -28 to 
Day -2)
Periods 1, 2 and 3i
Early 
Termination/
Discontinuatio
n (DC)
Follow- upg
Day -1
Day 1
Day 2
28-35 Days
Hours Post Dose
0
0.25
0.5
0.75
1
1.5
2
2.5
3
3.5
4
6
8
10
12
24
Informed consent
Xa
CRU confinement
X















X
Inclusion/exclusion 
criteria
X
X
Medical/medication
history (update)
X
Xb
Physical exam, height, 
and weightc
X
X
X
Safety laboratory
X
Xh
X
Demography
X
Pregnancy test (β-hCG)
in WOCBP
X
X
X
X
Contraception check
X
X
Xh
X
X
FSHd
X
Urine drug testing
X
X
Supine 12-Lead single 
ECG
X
Xh
X
Vital Signs
(Supine blood pressure 
and pulse rate)
X
X
Xh
X

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Table 1.
Schedule of Activities
Visit Identifier
Screening 
(Day -28 to 
Day -2)
Periods 1, 2 and 3i
Early 
Termination/
Discontinuatio
n (DC)
Follow- upg
Day -1
Day 1
Day 2
28-35 Days
Hours Post Dose
0
0.25
0.5
0.75
1
1.5
2
2.5
3
3.5
4
6
8
10
12
24
HBcAb, HBsAb, 
HBsAg, HCVAb, and 
HIV
X
COVID-19 
questionnairek
X
X
COVID-19 testingl
X
X
COVID-19 check 
temperaturem
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Study treatment 
administration
X
Pharmacokinetic blood 
sampling
Xe
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Pfizer Prep D1 banked 
samplej
X
Serious and nonserious 
Adverse event 
monitoring
X

















X
X
Concomitant 
treatments 
X














X
X
X
CRU dischargef
X

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Table 1.
Schedule of Activities
Visit Identifier
Screening 
(Day -28 to 
Day -2)
Periods 1, 2 and 3i
Early 
Termination/
Discontinuatio
n (DC)
Follow- upg
Day -1
Day 1
Day 2
28-35 Days
Hours Post Dose
0
0.25
0.5
0.75
1
1.5
2
2.5
3
3.5
4
6
8
10
12
24
a.
Must be completed before any study related procedures are performed.
b.
Period 1 - review changes in medical history since screening. Period 2 & 3 (for Cohort 1) and Period 2 (for Cohort 2) – review changes in medical history since prior 
period.
c.
Physical examination, including height and weight, at screening; brief physical examination on Day -1 of Period 1. The screening physical examination may be deferred 
to Day -1 of Period 1; however, height and weight must be done at screening to obtain BMI for determination of eligibility.
d.
Females who are amenorrheic for at least 12 consecutive months.
e.
Timepoint 0 PK blood sample will be collected predose (within 30 minutes prior to dosing).
f.
Participants will be discharged after collection of the 24-hour PK sample. Participants may remain at the CRU between study periods at the discretion of the investigator.
g.
Contact may occur via telephone contact and must occur 28 to 35 days from administration of the final dose of investigational product.
h.
At Period 3 only for Cohort-1 and Period-2 only for Cohort-2.
i.
Period 1, 2 and 3 for Cohort 1 and Period 1 and 2 for Cohort 2. 
j.
Period 1 only. Prep D1 Retained Research Samples for Genetics. If not collected on designated collection day, collect at the next available time point when biospecimens 
are collected in conjunction with a participant visit.
k.
Check exposure to positive subject, residence or travel in area of high incidence and COVID-19 related signs and symptoms. To be done at least 48 hours before and at 
each visit.
l.
The testing for COVID-19 pathogen by PCR will be performed at each visit. For participants admitted for residence, a subsequent COVID-19 test will be performed after 
4 days (ie, upon completion of 4 x 24 hours in house), or if they develop COVID-19 like symptom.
m.
To be done at least daily during residence.

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2. INTRODUCTION
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2.2. Background 
2.2.1. Clinical Overview
Prazosin hydrochloride (HCl) is an oral anti-hypertensive indicated for the treatment of 
primary and secondary hypertension and heart failure. Prazosin is a selective 
α-adrenoreceptor antagonist and is used either as single drug or combination treatment with 
diuretic and/or other antihypertensive drugs for proper patient response.1
The exact mechanism of the hypotensive action of prazosin is unknown. Prazosin causes a 
decrease in total peripheral resistance and was originally thought to have a direct relaxant 
action on vascular smooth muscle. Animal studies have suggested that the vasodilator effect 
of prazosin is also related to blockade of postsynaptic α-adrenoceptors. The results of dog 
forelimb experiments demonstrate that the peripheral vasodilator effect of prazosin is 
confined mainly to the level of the resistance vessels (arterioles). Unlike conventional 
α-blockers, the antihypertensive action of prazosin is usually not accompanied by reflex
tachycardia. Tolerance has not been observed to develop in long term therapy.1
Hemodynamic studies have been carried out in man following acute single dose 
administration and during the course of long term maintenance therapy. The results confirm 
that the therapeutic effect is a fall in blood pressure unaccompanied by a clinically significant 
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change in cardiac output, heart rate, renal blood flow and glomerular filtration rate. There is 
no measurable negative chronotropic effect. In clinical studies to date, prazosin 
hydrochloride has not increased plasma renin activity.1
In man, blood pressure is lowered in both the supine and standing positions. The effect is 
most pronounced on the diastolic blood pressure.
Prazosin HCl capsule formulation are available in strengths of 1 mg, 2 mg and 5 mg 
prazosin.1
Following oral administration of prazosin capsules, prazosin is readily absorbed from 
gastrointestinal track, Cmax reach in 1 to 3 hour post dose with a plasma half-life of 2 to 
3 hours. The absolute bioavailability of prazosin in adult humans ranging from 43.5% to 
69.3%.2 The rate of absorption of prazosin may be affected by the type of pharmaceutical 
formulation used, but not its extent.2
Following oral administration of a 5 mg prazosin capsule, reported Cmax of 35.9±17.3 ng/mL 
occurred in 1 to 3 hours post dose.2 The pharmacokinetics (PK) of prazosin is linear for both 
area under curve (AUC) and Cmax across the dose range of 0.5 mg to 10 mg.3 Food has no 
influence on either rate or extent of drug absorption.2
Prazosin is highly bound to plasma protein with plasma protein binding 97%. The volume 
of distribution following intravenous (IV) administration is approximately 42 liter (L).2
Animal studies indicate that prazosin hydrochloride is extensively metabolized, primarily by 
demethylation and conjugation, and excreted mainly via bile and urine. Less extensive human 
studies suggest similar metabolism and excretion in man. The total body clearance of prazosin 
ranged from approximately 10 to 14 L/h.2
Prazosin is a well tolerated drug with an established safety profile. Product is contraindicated 
in patients with known sensitivity to quinazolines, prazosin hydrochloride. The most frequent 
adverse effect associated with prazosin hydrochloride therapy are dizziness 10.3%, headache 
7.8%, drowsiness 7.6%, lack of energy 6.9%, weakness 6.5%, palpitations 5.3%, and nausea 
4.9%. In most instances, side effects have disappeared with continued therapy or have been 
tolerated with no decrease in dose of drug.1
2.3. Benefit/Risk Assessment
Prazosin HCl capsule is not expected to provide any clinical benefit to healthy participants. 
This study is designed primarily to generate pharmacokinetic and safety data to support 
regulatory registration of prazosin HCl capsules at 1 mg, 2 mg and 5 mg strength 
manufactured at Pfizer Ascoli.
More detailed information about the known and expected benefits and risks and reasonably 
expected adverse events of prazosin HCl capsules may be found in the Minipress® United 
States Package Insert (USPI) which is the single reference safety document (SRSD) for this 
study.

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2.3.1. Risk Assessment
Potential Risk of Clinical Significance
Summary of Data/Rationale for Risk
Mitigation Strategy
Study Intervention(s) :Prazosin HCl capsule
Potential risks associated with prazosin 
HCl capsules include the following: 
Dizziness (vertigo), headache, drowsiness, 
lack of energy, weakness, nausea and 
palpitations. These risks represent AEs of 
special interest for with prazosin HCl
capsules (see Section 8.3.8).
The potential risks are based on product 
labeling for prazosin HCl capsules.
AEs and clinical laboratory results will 
be monitored on an ongoing basis. 
Instructions for managing potential cases 
of DILI are provided (see Appendix 6).
Other
The COVID-19 pandemic may pose risks 
to study participation.
Participants may have increased risk of 
SARS-CoV-2 infection by undergoing a 
study procedure at a study facility.
Inclusion of COVID-19 specific 
assessments according to the Schedule of 
Activities.

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2.3.2. Overall Benefit/Risk Conclusion
Taking into account the measures to minimize risk to study participants, prazosin HCl 
capsule is not expected to provide any clinical benefit to healthy participants.
3. OBJECTIVES AND ENDPOINTS
Objectives
Endpoints
Primary: 
Primary: 

To demonstrate bioequivalence between 
prazosin HCL 1 and 2 mg capsules 
manufactured at the proposed site (Ascoli) 
versus prazosin HCl 2 mg capsules 
manufactured at current site (Barceloneta) 
under fasting conditions in healthy adult 
participants. 

To demonstrate bioequivalence between 
prazosin HCl 5 mg capsules manufactured at 
the proposed site (Ascoli) versus prazosin HCl 
5 mg capsules manufactured at current site 
(Barceloneta) under fasting conditions in 
healthy adult participants.

AUClast and Cmax of prazosin.
Secondary: 
Secondary: 

To evaluate the safety and tolerability of 
prazosin HCl capsules.

AUCinf (if data permit), t½ (if data permit) and 
Tmax of prazosin.

Adverse events (AEs).
4. STUDY DESIGN
4.1. Overall Design
This will be a 2 Cohort, open-label, randomized, single dose study in healthy adult male 
and/or female participants.
Cohort 1 will be crossover with 3 treatments, 3 periods, 6 sequences. Cohort 2 will be 
crossover with 2 treatments, 2 periods, 2 sequences.
Approximately 36 participants will be enrolled in each Cohort 1 and Cohort 2. Participants
enrolled in Cohort 1 will not be eligible for Cohort 2 and vice versa. Dropouts for non-safety 
reasons may be replaced at the discretion of the sponsor and investigator. Participants in 
Cohort 1 will be assigned to 1 of the 6 sequences according to a computer-generated 
randomization schedule (see Table 2). Participants in Cohort 2 will be assigned to 1 of the 2 
sequences according to a computer-generated randomization schedule (see Table 3).

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Table 2.
Sequences for Cohort 1
Sequence
N
Period 1
Washout 
Period
Period 2
Washout 
Period
Period 3
1
6
Treatment A
At least
7 days
Treatment B
At least
7 days
Treatment C
2
6
Treatment B
Treatment C
Treatment A
3
6
Treatment C
Treatment A
Treatment B
4
6
Treatment A
Treatment C
Treatment B
5
6
Treatment B
Treatment A
Treatment C
6
6
Treatment C
Treatment B
Treatment A
Treatment A: Prazosin HCL 1 x 2 mg capsule manufactured at the current site (Barceloneta) under fasting 
conditions (Reference).
Treatment B: Prazosin HCl 1 x 2 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test1).
Treatment C: Prazosin HCl 2 x 1 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test2).
Table 3.
Sequences for Cohort 2
Sequence
N
Period 1
Washout Period
Period 2
1
18
Treatment D
At least 7 days
Treatment E
2
18
Treatment E
Treatment D
Treatment D: Prazosin HCl 1 x 5 mg capsule manufactured at the current site (Barceloneta) under fasting 
conditions (Reference).
Treatment E: Prazosin HCl 1 x 5 mg capsule manufactured at the proposed site (Ascoli) under fasting 
conditions (Test).
There will be a minimum 7 day washout period between successive doses (ie, administration 
of subsequent doses of study medication will not occur until at least 7 days after the previous 
dose of study medication).
Screening evaluation will occur within 28 days prior to the first dose of study medication.
Day -1 is defined as the day prior to the first day of dosing (Day 1) in each period.
Participants will be admitted to the clinical research unit (CRU) on Day -1 and will remain 
confined in the CRU for approximately 3 days and 2 nights during each period until the 
collection of the 24 hour PK sample. Participants may remain at the CRU between study 
periods at the discretion of the investigator. The total duration of participation from the 
Screening Visit to Discharge will be approximately 6 weeks, and from the Screening Visit to 
Follow-up will be approximately 11 weeks.
On Day 1 of each period, participants will receive a single dose of investigational product as 
per randomization schedule. Study treatments will be administered with approximately 
240 mL of ambient temperature water under fasting conditions (overnight fast and no food 
until 4 hours after dosing). Water will be allowed without restriction until 1 hour prior to 
dosing and may be consumed without restriction beginning 1 hour after dosing.

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Blood samples for the analysis of prazosin in plasma will be obtained predose (immediately 
prior to dosing) and postdose as outlined in Schedule of Activities (SoA) table.
Tolerability and safety will be assessed for all treatments by monitoring AEs.
4.2. Scientific Rationale for Study Design
This study is intended to be a pivotal BE study to support the transfer of manufacturing 
operations for prazosin HCl capsules (1 mg, 2 mg and 5 mg) from Barceloneta to Ascoli with 
the associated process changes and regulatory registration.
The study design follows the United States (US) Food and Drug Administration (FDA)
product specific BE guidance for prazosin hydrochloride oral capsules.4
4.2.1. Choice of Contraception/Barrier Requirements
Human reproductive safety data are not available for prazosin HCl. Therefore, the use of a 
highly effective method of contraception is required (see Appendix 4).
4.2.2. Collection of Retained Research Samples
Retained Research Samples will be collected and stored for further analyses which may, for 
example, provide greater understanding of the study intervention.
 
 
 
 
 
 
 
 
 
 
CCI
CCI

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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 visit or the last scheduled procedure shown in the SoA.
The end of the study is defined as the date of the last visit of the last participant in the study 
or last schedule procedure shown in the SoA for the last participant in the study.
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.
CCI
CCI
CCI

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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. Participants 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. Male and female participants who are overtly healthy as determined by medical 
evaluation including medical history, full physical examination, vital signs, 12-lead 
electrocardiogram (ECG), and/or clinical laboratory tests.
3. Participants who are willing and able to comply with all scheduled visits, treatment 
plan, laboratory tests, lifestyle considerations , and other study procedures.
Weight:
4. BMI of 17.5 to 30.5 kg/m2; and a total body weight >50 kg (110 lb).
Informed Consent:
5. 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).
2. Any condition possibly affecting drug absorption (eg, gastrectomy).
3. History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, 
HBcAb or HCVAb. Hepatitis B vaccination is allowed.
4. Other medical or psychiatric condition including recent (within the past year) or 
active suicidal ideation/behavior or laboratory abnormality or other conditions or 

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situations related to COVID-19 pandemic (eg. Contact with positive case, residence, 
or travel to an area with high incidence) that may increase the risk of study 
participation or, in the investigator’s judgment, make the participant inappropriate for 
the study.
Prior/Concomitant Therapy:
5. Use of prescription or nonprescription drugs and dietary and herbal supplements 
within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study 
intervention. (Refer to Section 6.8 Concomitant Therapy for additional details).
6. Current use of any prohibited concomitant medication(s) or those unwilling/unable to 
use a permitted concomitant medication(s). Refer to Section 6.8 Concomitant 
Therapy.
Prior/Concurrent Clinical Study Experience:
7. 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:
8. A positive urine drug test.
9. 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.
10. Baseline standard 12-lead ECG that demonstrates clinically relevant abnormalities that 
may affect participant safety or interpretation of study results (eg, baseline QTcF
interval >450 msec, complete LBBB, signs of an acute or indeterminate- myocardial
infarction, ST interval and T-wave changes suggestive of myocardial ischemia, 
second or third-degree AV block, or serious bradyarrhythmias or tachyarrhythmias). 
If the baseline uncorrected QT interval is >450 msec, this interval should be 
rate--corrected using the Fridericia method and the resulting QTcF should be used for 
decision making and reporting. If QTcF exceeds 450 msec, or QRS exceeds 
120 msec, the ECG should be repeated 2 more times and the average of the 3 QTcF or 
QRS values should be used to determine the participant’s eligibility. 
Computer-interpreted ECGs should be overread by a physician experienced in 
reading ECGs before excluding a participant.

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11. Participants with ANY of the following abnormalities in clinical laboratory tests at 
screening, as assessed by the study-specific laboratory and confirmed by a single 
repeat test, if deemed necessary: 

AST or ALT level ≥1.5 × ULN;

Total bilirubin level ≥1.5 × ULN; participants with a history of Gilbert's 
syndrome may have direct bilirubin measured and would be eligible for this study 
provided the direct bilirubin level is≤ULN.
Other Exclusions:
12. 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).
13. Blood donation (excluding plasma donations) of approximately 1 pint (500 mL) or 
more within 60 days prior to dosing.
14. Use of tobacco- or nicotine-containing products in excess of the equivalent of 
5 cigarettes per day. For chewing tobacco, one chew is equivalent to approximately 
2-3 cigarettes, so participants would be limited to 2 or less chews per day.
15. History of sensitivity to prazosin hydrochloride or any of the components in the 
formulation of the study products.
16. Unwilling or unable to comply with the criteria in the Lifestyle Considerations
section of this protocol.
17. 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.
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 4 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 

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(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 to admission to the clinical 
research unit (CRU) and continue abstaining from alcohol until collection of the final 
PK sample of each study period. Participants may undergo an alcohol breath test or 
blood alcohol test at the discretion of the investigator.

Participants will abstain from the use of tobacco- or nicotine-containing products for 
24 hours prior to dosing and during confinement in the CRU.
5.3.3. Activity

Participants will abstain from strenuous exercise (eg, heavy lifting, weight training, 
calisthenics, aerobics) for at least 48 hours prior to each blood collection for clinical 
laboratory tests. Walking at a normal pace will be permitted;

In order to standardize the conditions on PK sampling days, participants will be 
required to refrain from lying down (except when required for BP, pulse rate, and 
ECG measurements), eating, and drinking beverages other than water during the first 
4 hours after dosing;

If participant is laying down, to avoid the situation of sudden hypotension and 
dizziness, he/she should stand up gradually such as sitting before standing up. 

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5.3.4. Contraception
The investigator or his or her designee, in consultation with the participant, will confirm that 
the participant has selected an appropriate method of contraception for the individual 
participant and his or her partner(s) from the permitted list of contraception methods (see 
Appendix 4 Section 10.4.4) and will confirm that the participant has been instructed in its 
consistent and correct use. At time points indicated in the SoA, the investigator or designee 
will inform the participant of the need to use highly effective contraception consistently and 
correctly and document the conversation and the participant’s affirmation in the participant’s 
chart (participants need to affirm their consistent and correct use of at least 1 of the selected 
methods of contraception) considering that their risk for pregnancy may have changed since 
the last visit. In addition, the investigator or designee will instruct the participant to call 
immediately if the selected contraception method is discontinued or if pregnancy is known or 
suspected in the participant or partner.
5.4. Screen Failures
Screen failures are defined as participants who consent to participate in the clinical study but 
are not subsequently randomly assigned to study intervention. Screen failure data are 
collected and remain as source and are not reported on the CRF.
Individuals who do not meet the criteria for participation in this study (screen failure) may 
not be rescreened.
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY
Study intervention is defined as any investigational intervention(s), marketed product(s), 
placebo, medical device(s), or study procedure(s) intended to be administered to a study 
participant according to the study protocol.
For the purposes of this protocol, study intervention refers to investigational product.
6.1. Study Intervention(s) Administered
For the purposes of this protocol, study intervention refers to prazosin HCl capsules.
Prazosin HCl 2 mg and 5 mg capsules, manufactured at Pfizer Pharmaceutical, Barceloneta, 
Puerto Rico and prazosin HCl 1 mg, 2 mg and 5 mg capsules, manufactured at Pfizer 
Pharmaceutical, Ascoli, Italy will be supplied to the CRU along with individual dosing 
containers for unit dosing.
Pivotal BE study capsules will be supplied to the CRU in multidose labeled containers (in 
sufficient number to allow unopened containers to be kept as retains).
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). Investigator site personnel will 
administer study intervention during each period with ambient temperature water to a total 

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volume of approximately 240 mL. Participants will swallow the study intervention whole, 
and will not manipulate or chew the study intervention prior to swallowing. 
In order to standardize the conditions on PK sampling days, all participants will be required 
to refrain from lying down (except when required for BP, pulse rate, and ECG 
measurements), eating, and drinking beverages other than water during the first 4 hours after 
dosing.
6.2. Preparation, Handling, Storage, and Accountability
1. The investigator or designee must confirm appropriate temperature conditions have 
been maintained during transit for all study interventions received and any 
discrepancies are reported and resolved before use of the study intervention. 
2. Only participants enrolled in the study may receive study intervention and only 
authorized site staff may supply or administer study intervention. All study 
interventions must be stored in a secure, environmentally controlled, and monitored 
(manual or automated recording) area in accordance with the labeled storage 
conditions with access limited to the investigator and authorized site staff. At a 
minimum, daily minimum and maximum temperatures for all site storage locations 
must be documented and available upon request. Data for nonworking days must 
indicate the minimum and maximum temperatures since previously documented for 
all site storage locations upon return to business.
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 IP manual.
4. Any storage conditions stated in the SRSD will be superseded by the storage 
conditions stated on the label.
5. Study interventions should be stored in their original containers.
6. The investigator, institution, or the head of the medical institution (where applicable) 
is responsible for study intervention accountability, reconciliation, and record 
maintenance (ie, receipt, reconciliation, and final disposition records), such as the 
IPAL or sponsor-approved equivalent. All study interventions will be accounted for 
using a study intervention accountability form/record.
7. Further guidance and information for the final disposition of unused study 
interventions are provided in the IP manual. All destruction must be adequately 
documented. If destruction is authorized to take place at the investigator site, the 

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investigator must ensure that the materials are destroyed in compliance with 
applicable environmental regulations, institutional policy, and any special instructions 
provided by Pfizer
8. All pivotal BE retained capsules should be stored by the investigator site or with a 
third-party vendor. Sample retention is the responsibility of the entity performing the 
BE study.
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.
Capsules will be prepared at the CRU in the individual dosing containers by 2 operators, 1 of 
whom is an appropriately qualified and experienced member of the study staff (eg, physician, 
nurse, physician’s assistant, nurse practitioner, pharmacy assistant/technician, or pharmacist).
The capsules will be provided in unit dose containers and labeled in accordance with Pfizer 
regulations and the clinical site’s labeling requirements. 
6.3. Measures to Minimize Bias: Randomization and Blinding
6.3.1. Allocation to Study Intervention
The investigator’s knowledge of the treatment should not influence the decision to enroll a 
particular participant or affect the order in which participants are enrolled.
The investigator will assign participant numbers to the participants as they are screened for 
the study. Pfizer will provide a randomization schedule to the investigator and, in accordance 
with the randomization numbers, the participant will receive the study treatment regimen 
assigned to the corresponding randomization number.
6.4. Study Intervention Compliance
When participants are dosed at the site, they will receive study intervention directly from the 
investigator or designee, under medical supervision. The date and time of each dose 
administered in the 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 other than the person administering the 
study intervention. Study site personnel will examine each participant’s mouth to ensure that 
the study intervention was ingested.

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6.5. Dose Modification
Does modification is not applicable to this study.
6.6. Continued Access to Study Intervention After the End of the Study
No intervention will be provided to study participants at the end of their study participation.
6.7. Treatment of Overdose
For this study, any dose of study intervention greater than 5 mg within a 24-hour time period 
will be considered an 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 study intervention 
(whichever is longer).
3. Document the quantity of the excess dose as well as the duration of the overdose in 
the CRF.
4. Overdose is reportable to Pfizer Safety only when associated with an SAE.
5. Obtain a blood sample for PK analysis within 1 day from the date of the last dose of 
study intervention if requested by the medical monitor (determined on a case-by-case 
basis).
Decisions regarding dose interruptions or modifications will be made by the investigator in 
consultation with the medical monitor based on the clinical evaluation of the participant.
6.8. Concomitant Therapy
Use of prescription or nonprescription drugs and dietary and herbal supplements are 
prohibited within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study 
intervention. Limited use of nonprescription medications that are not believed to affect 
participant safety or the overall results of the study may be permitted on a case-by-case basis 
following approval by the sponsor. Acetaminophen/paracetamol may be used at doses of 
≤1 g/day.
Females using hormonal contraceptives or 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. Depo-Provera® must be discontinued at least 6 months prior to the first dose of 
study treatment.

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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.
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL
7.1. Discontinuation of Study Intervention
It may be necessary for a participant to permanently discontinue study intervention. Reasons 
for permanent discontinuation of study intervention include the following

significant change in vital signs or 

adverse event. 
If study intervention is permanently discontinued, the participant will not remain in the study 
for further evaluation. See the SoA for data to be collected at the time of discontinuation of 
study intervention.
7.2. Participant Discontinuation/Withdrawal From the Study
A participant may withdraw from the study at any time at his/her own request. Reasons for 
discontinuation from the study include the following:

Refused further study procedures;

Lost to follow-up;

Death;

Study terminated by sponsor;
At the time of discontinuing from the study, if possible, an early discontinuation visit should 
be conducted. See the SoA for assessments to be collected at the time of study 
discontinuation and follow-up and for any further evaluations that need to be completed. 
The early discontinuation visit applies only to participants who are enrolled/randomized and 
then are prematurely withdrawn from the study. Participants should be questioned regarding 
their reason for withdrawal.
The participant will be permanently discontinued from the study intervention and the study at 
that time.

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If a participant withdraws from the study, he/she may request destruction of any remaining 
samples taken and not tested, and the investigator must document any such requests in the 
site study records and notify the sponsor accordingly.
If the participant withdraws from the study and also withdraws consent (see Section 7.2.1) 
for disclosure of future information, no further evaluations should be performed and no 
additional data should be collected. The sponsor may retain and continue to use any data 
collected before such withdrawal of consent.
7.2.1. Withdrawal of Consent 
Participants who request to discontinue receipt of study intervention will remain in the study 
and must continue to be followed for protocol-specified follow-up procedures. The only 
exception to this is when a participant specifically withdraws consent for any further contact 
with him or her or persons previously authorized by the participant to provide this 
information. Participants should notify the investigator in writing of the decision to withdraw 
consent from future follow--up, whenever possible. The withdrawal of consent should be 
explained in detail in the medical records by the investigator, as to whether the withdrawal is 
only from further receipt of study intervention or also from study procedures and/or 
posttreatment study follow--up, and entered on the appropriate CRF page. In the event that 
vital status (whether the participant is alive or dead) is being measured, publicly available 
information should be used to determine vital status only as appropriately directed in 
accordance with local law.
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:

The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible. Counsel the participant on the importance of maintaining the 
assigned visit schedule and ascertain whether the participant wishes to and/or should 
continue in the study;

Before a participant is deemed lost to follow-up, the investigator or designee must 
make every effort to regain contact with the participant (where possible, 3 telephone 
calls and, if necessary, a certified letter to the participant’s last known mailing 
address or local equivalent methods). These contact attempts should be documented 
in the participant’s medical record;

Should the participant continue to be unreachable, he/she will be considered to have 
withdrawn from the study. 

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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.
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.

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The total blood sampling volume for individual participants in this study is approximately 
260 mL. The actual collection times of blood sampling may change. Additional blood 
samples may be taken for safety assessments at times specified by Pfizer, provided the total 
volume taken during the study does not exceed 550 mL during any period of 56 consecutive 
days.
To prepare for study participation, participants will be instructed on the information in the 
Lifestyle Considerations and Concomitant Therapy sections of the protocol.
8.1. Efficacy Assessments
Not applicable.
8.2. Safety Assessments
Planned time points for all safety assessments are provided in the SoA. Unscheduled clinical 
laboratory measurements may be obtained at any time during the study to assess any 
perceived safety issues.
8.2.1. Physical Examinations
A complete 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 listening to the lungs, blood pressure, pulse rate and cardiac auscultation, and 
participant-reported symptoms.
Physical examinations may be conducted by a physician, trained physician's assistant, or 
nurse practitioner as acceptable according to local regulation. 
Height and weight will also be measured and recorded as per the SoA. For measuring weight, 
a scale with appropriate range and resolution is used and must be placed on a stable, flat 
surface. Participants must remove shoes, bulky layers of clothing, and jackets so that only 
light clothing remains. They must also remove the contents of their pockets and remain still 
during measurement of weight. The site should ensure the regular calibration of their weight 
scale according to manufacturer’s instruction.
Physical examination findings collected during the study will be considered source data and 
will not be required to be reported, unless otherwise noted. Any untoward physical 
examination findings that are identified during the active collection period and meet the 
definition of an AE or SAE (Appendix 3) must be reported according to the processes in 
Sections 8.3.1 to 8.3.3.

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8.2.2. 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.
If a participant has symptoms suggestive of orthostasis, but not documented orthostatic 
hypotension, repeated measurements of supine/standing BP 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]).
8.2.3. Electrocardiograms
Supine 12-lead ECGs utilizing limb leads (with a 10 second rhythm strip) should be collected 
at times specified in the SoA section of this protocol using an ECG machine that 
automatically calculates the heart rate and measures PR, QT, and QTc intervals and QRS 
complex. Alternative lead placement methodology using torso leads (eg, Mason-Likar) 
should not be used given the potential risk of discrepancies with ECGs acquired using 
standard limb lead placement. All scheduled ECGs should be performed after the participant
has rested quietly for at least 5 minutes in a supine position. 

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In some cases, it may be appropriate to repeat abnormal ECGs to rule out improper lead 
placement as contributing to the ECG abnormality. It is important that leads be placed in the 
same positions each time in order to achieve precise ECG recordings. If a machine-read QTc 
value is prolonged, as defined above, repeat measurements may not be necessary if a 
qualified medical provider’s interpretation determines that the QTcF values are in the 
acceptable range.
ECG values of potential clinical concern are listed in Appendix 7.
8.2.4. Clinical Safety Laboratory Assessments
See Appendix 2 for the list of clinical safety laboratory tests to be performed and the SoA for 
the timing and frequency. All protocol-required laboratory assessments, as defined in 
Appendix 2, must be conducted in accordance with the laboratory manual and the SoA. 
Unscheduled clinical laboratory measurements may be obtained at any time during the study 
to assess any perceived safety issues.
The investigator must review the laboratory report, document this review, and record any 
clinically relevant changes occurring during the study in the AE section of the CRF.
Clinically significant abnormal laboratory findings are those which are not associated with 
the underlying disease, unless judged by the investigator to be more severe than expected for 
the participant's condition.
All laboratory tests with values considered clinically significantly abnormal during 
participation in the study or within 28 days after the last dose of study intervention should be 
repeated until the values return to normal or baseline or are no longer considered clinically 
significant by the investigator or medical monitor.
If such values do not return to normal/baseline within a period of time judged reasonable by 
the investigator, the etiology should be identified and the sponsor notified.
See Appendix 6 for suggested actions and follow-up assessments in the event of potential 
drug-induced liver injury.
Participants may undergo random urine drug testing at the discretion of the investigator.
Drug testing conducted prior to dosing must be negative for participants to receive study 
intervention. 
8.2.5. COVID-19 specific assessments 
Participants will be tested for SARS-COVID-19 infection by PCR prior to being admitted to 
the clinic and at each visit for confinement and a subsequent COVID-19 test will be 
performed after 4 days (i.e. upon completion of 4 x 24 hours in house), or if they develop 
COVID-19 like symptoms. COVID-19 questionaire and temperature check will be pefromed 
per the SoA. Additional testing may be required by local regulations or by the Principal 
Investigator.

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8.2.6. Pregnancy Testing 
Pregnancy tests may be urine or serum tests, but must have a sensitivity of at least 
25 mIU/mL. Pregnancy tests will be performed in WOCBP at the times listed in the SoA.
Following a negative pregnancy test result at screening, appropriate contraception must be 
commenced and a second negative pregnancy test result will be required at the baseline visit 
prior the participant’s receiving the study intervention. Pregnancy tests will also be done 
whenever 1 menstrual cycle is missed during the active treatment period (or when potential 
pregnancy is otherwise suspected) and at the end of the study. Pregnancy tests may also be 
repeated if requested by IRBs/ ECs or if required by local regulations. If a urine test cannot 
be confirmed as negative (eg, an ambiguous result), a serum pregnancy test is required. In 
such cases, the participant must be excluded if the serum pregnancy result is positive.
8.3. Adverse Events, Serious Adverse Events, and Other Safety Reporting
The definitions of an AE and an SAE can be found in Appendix 3.
AEs may arise from symptoms or other complaints reported to the investigator by the 
participant (or, when appropriate, by a caregiver, surrogate, or the participant's legally 
authorized representative), or they may arise from clinical findings of the Investigator or 
other healthcare providers (clinical signs, test results, etc.).
The investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE or SAE and remain responsible to pursue 
and obtain adequate information both to determine the outcome and to assess whether the 
event meets the criteria for classification as an SAE or caused the participant to discontinue 
the study (see Section 7.1). 
During the active collection period as described in Section 8.3.1, each participant will be 
questioned about the occurrence of AEs in a nonleading manner.
In addition, the investigator may be requested by Pfizer Safety to obtain specific follow-up 
information in an expedited fashion.
8.3.1. Time Period and Frequency for Collecting AE and SAE Information
The time period for actively eliciting and collecting AEs and SAEs (“active collection 
period”) for each participant begins from the time the participant provides informed consent, 
which is obtained before the participant’s participation in the study (ie, before undergoing 
any study-related procedure and/or receiving study intervention), through and including a 
minimum of 28 calendar days after the last administration of the study intervention.
Follow-up by the investigator continues throughout and after the active collection period and 
until the AE or SAE or its sequelae resolve or stabilize at a level acceptable to the 
investigator.
For participants who are screen failures, the active collection period ends when screen failure 
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If the participant withdraws from the study and also withdraws consent for the collection of 
future information, the active collection period ends when consent is withdrawn.
If a participant permanently discontinues or temporarily discontinues study because of an AE 
or SAE, the AE or SAE must be recorded on the CRF and the SAE reported using the CT 
SAE Report Form.
Investigators are not obligated to actively seek information on AEs or SAEs after the 
participant has concluded study participation. However, if the investigator learns of any SAE, 
including a death, at any time after a participant has completed the study, and he/she 
considers the event to be reasonably related to the study intervention, the investigator must 
promptly report the SAE to Pfizer using the CT SAE Report Form.
8.3.1.1. Reporting SAEs to Pfizer Safety
All SAEs occurring in a participant during the active collection period as described in 
Section 8.3.1 are reported to Pfizer Safety on the CT SAE Report Form immediately upon 
awareness and under no circumstance should this exceed 24 hours, as indicated in 
Appendix 3. The investigator will submit any updated SAE data to the sponsor within 
24 hours of it being available.
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF
All nonserious AEs and SAEs occurring in a participant during the active collection period, 
which begins after obtaining informed consent as described in Section 8.3.1, will be recorded 
on the AE section of the CRF.
The investigator is to record on the CRF all directly observed and all spontaneously reported 
AEs and SAEs reported by the participant.
8.3.2. Method of Detecting AEs and SAEs
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Appendix 3.
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
nonleading verbal questioning of the participant is the preferred method to inquire about 
AE occurrences.
8.3.3. Follow-Up of AEs and SAEs
After the initial AE or SAE report, the investigator is required to proactively follow each 
participant at subsequent visits/contacts. For each event, the investigator must pursue and 
obtain adequate information until resolution, stabilization, the event is otherwise explained, 
or the participant is lost to follow-up (as defined in Section 7.3).
In general, follow-up information will include a description of the event in sufficient detail to 
allow for a complete medical assessment of the case and independent determination of 

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possible causality. Any information relevant to the event, such as concomitant medications 
and illnesses, must be provided. In the case of a participant death, a summary of available 
autopsy findings must be submitted as soon as possible to Pfizer Safety. 
Further information on follow-up procedures is given in Appendix 3.
8.3.4. Regulatory Reporting Requirements for SAEs
Prompt notification by the investigator to the sponsor of an SAE is essential so that legal 
obligations and ethical responsibilities toward the safety of participants and the safety of a 
study intervention under clinical investigation are met.
The sponsor has a legal responsibility to notify both the local regulatory authority and other 
regulatory agencies about the safety of a study intervention under clinical investigation. The 
sponsor will comply with country-specific regulatory requirements relating to safety 
reporting to the regulatory authority, IRBs/ECs, and investigators.
Investigator safety reports must be prepared for SUSARs according to local regulatory 
requirements and sponsor policy and forwarded to investigators as necessary.
An investigator who receives SUSARs or other specific safety information (eg, summary or 
listing of SAEs) from the sponsor will review and then file it along with the SRSD(s) for the 
study and will notify the IRB/EC, if appropriate according to local requirements.
8.3.5. Environmental Exposure, Exposure During Pregnancy or Breastfeeding, and 
Occupational Exposure
Environmental exposure, occurs when a person not enrolled in the study as a participant 
receives unplanned direct contact with or exposure to the study intervention. Such exposure 
may or may not lead to the occurrence of an AE or SAE. Persons at risk for environmental 
exposure include healthcare providers, family members, and others who may be exposed. An 
environmental exposure may include exposure during pregnancy, exposure during 
breastfeeding, and occupational exposure.
Any such exposure to the study intervention under study are reportable to Pfizer Safety 
within 24 hours of investigator awareness.
8.3.5.1. Exposure During Pregnancy
An EDP occurs if: 

A female participant is found to be pregnant while receiving or after discontinuing 
study intervention.

A male participant who is receiving or has discontinued study intervention exposes a 
female partner prior to or around the time of conception.

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
A female is found to be pregnant while being exposed or having been exposed to 
study intervention due to environmental exposure. Below are examples of 
environmental EDP:

A female family member or healthcare provider reports that she is pregnant after 
having been exposed to the study intervention by ingestion.

A male family member or healthcare provider who has been exposed to the study 
intervention by ingestion 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 24 hours 
after the last dose.

If EDP occurs in the setting of environmental exposure, the investigator must report 
information to Pfizer Safety using the CT SAE Report Form and EDP Supplemental 
Form. Since the exposure information does not pertain to the participant enrolled in 
the study, the information is not recorded on a CRF; however, a copy of the 
completed CT SAE Report Form is maintained in the investigator site file.
Follow-up is conducted to obtain general information on the pregnancy and its outcome for 
all EDP reports with an unknown outcome. The investigator will follow the pregnancy until 
completion (or until pregnancy termination) and notify Pfizer Safety of the outcome as a 
follow-up to the initial EDP Supplemental Form. In the case of a live birth, the structural 
integrity of the neonate can be assessed at the time of birth. In the event of a termination, the 
reason(s) for termination should be specified and, if clinically possible, the structural 
integrity of the terminated fetus should be assessed by gross visual inspection (unless 
preprocedure test findings are conclusive for a congenital anomaly and the findings are 
reported).
Abnormal pregnancy outcomes are considered SAEs. If the outcome of the pregnancy meets 
the criteria for an SAE (ie, ectopic pregnancy, spontaneous abortion, intrauterine fetal 
demise, neonatal death, or congenital anomaly), 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;

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
Neonatal deaths that occur within 1 month of birth should be reported, without regard 
to causality, as SAEs. In addition, infant deaths after 1 month should be reported as 
SAEs when the investigator assesses the infant death as related or possibly related to 
exposure to the study intervention. 
Additional information regarding the EDP may be requested by the sponsor. Further 
follow-up of birth outcomes will be handled on a case-by-case basis (eg, follow-up on 
preterm infants to identify developmental delays). In the case of paternal exposure, the 
investigator will provide the participant with the Pregnant Partner Release of Information 
Form to deliver to his partner. The investigator must document in the source documents that 
the participant was given the Pregnant Partner Release of Information Form to provide to his 
partner.
8.3.5.2. Exposure During Breastfeeding
An exposure during breastfeeding occurs if: 

A female participant is found to be breastfeeding while receiving or after 
discontinuing study intervention.

A female is found to be breastfeeding while being exposed or having been exposed to 
study intervention (ie, environmental exposure). An example of environmental 
exposure during breastfeeding is a female family member or healthcare provider who 
reports that she is breastfeeding after having been exposed to the study intervention 
by ingestion.
The investigator must report exposure during breastfeeding to Pfizer Safety within 24 hours 
of the investigator’s awareness, irrespective of whether an SAE has occurred. The 
information must be reported using the CT SAE Report Form. When exposure during 
breastfeeding occurs in the setting of environmental exposure, the exposure information does 
not pertain to the participant enrolled in the study, so the information is not recorded on a 
CRF. However, a copy of the completed CT SAE Report Form is maintained in the 
investigator site file.
An exposure during breastfeeding report is not created when a Pfizer drug specifically 
approved for use in breastfeeding women (eg, vitamins) is administered in accord with 
authorized use. However, if the infant experiences an SAE associated with such a drug, the 
SAE is reported together with the exposure during breastfeeding.
8.3.5.3. Occupational Exposure
The investigator must report any instance of occupational exposure to Pfizer Safety within 24 
hours of the investigator’s awareness using the CT SAE Report Form regardless of whether 
there is an associated SAE. Since the information about the occupational exposure does not 
pertain to a participant enrolled in the study, the information is not recorded on a CRF; 
however, a copy of the completed CT SAE Report Form must be maintained in the 
investigator site file.

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8.3.6. Cardiovascular and Death Events
Not applicable.
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not Qualifying as AEs 
or SAEs
Not Applicable.
8.3.8. Adverse Events of Special Interest
Not Applicable.
8.3.8.1. Lack of Efficacy
This section is not applicable because efficacy is not expected in the study population.
8.3.9. Medical Device Deficiencies
Not Applicable.
8.3.10. Medication Errors
Medication errors may result from the administration or consumption of the study 
intervention by the wrong participant, or at the wrong time, or at the wrong dosage strength.
Exposures to the study intervention under study may occur in clinical trial settings, such as 
medication errors.
Safety Event
Recorded on the CRF
Reported on the CT SAE Report
Form to Pfizer Safety Within 
24 Hours of Awareness
Medication errors All (regardless of whether 
associated with an AE)
Only if associated with an SAE
Medication errors include:

Medication errors involving participant exposure to the study intervention;

Potential medication errors or uses outside of what is foreseen in the protocol that do 
or do not involve the study participant.
Such medication errors occurring to a study participant are to be captured on the medication 
error page of the CRF, which is a specific version of the AE page.
In the event of a medication dosing error, the sponsor should be notified within 24 hours.

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Whether or not the medication error is accompanied by an AE, as determined by the 
investigator, the medication error is recorded on the medication error page of the CRF and, if 
applicable, any associated AE(s), serious and nonserious, are recorded on the AE page of the 
CRF.
Medication errors should be reported to Pfizer Safety within 24 hours on a CT SAE Report 
Form only when associated with an SAE.
8.4. Pharmacokinetics 
Blood samples of approximately 4 mL, to provide approximately 1.5 mL plasma, will be 
collected for measurement of plasma concentrations of prazosin as specified in the SoA.
Instructions for the collection and handling of biological samples will be provided in the 
laboratory manual or by the sponsor. The actual date and time (24-hour clock time) of each 
sample will be recorded.
The actual times may change, but the number of samples will remain the same. All efforts 
will be made to obtain the samples at the exact nominal time relative to dosing. Collection of 
samples up to and including 10 hours after dose administration that are obtained within 
10% of the nominal time (eg, within 6 minutes of a 60-minute sample) relative to dosing will 
not be captured as a protocol deviation, as long as the exact time of the collection is noted on 
the source document and data collection tool (eg, CRF/DCT). Collection of samples more 
than 10 hours after dose administration that are obtained ≤1 hour away from the nominal 
time relative to dosing will not be captured as a protocol deviation, as long as the exact time 
of the collection is noted on the source document and data collection tool (eg, CRF/DCT). 
 
Genetic analyses will not be performed on these plasma samples. Participant confidentiality 
will be maintained.
Samples collected for measurement of plasma concentrations of prazosin will be analyzed 
using a validated analytical method in compliance with applicable standard operating 
procedures (SOPs).
The PK samples must be processed and shipped as indicated in the instructions provided to 
the investigator site to maintain sample integrity. Any deviations from the PK sample 
handling procedure (eg, sample collection and processing steps, interim storage or shipping 
conditions), including any actions taken, must be documented and reported to the sponsor.
On a case-by-case basis, the sponsor may make a determination as to whether sample 
integrity has been compromised.
CCI

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8.5. Genetics
8.5.1. Specified Genetics
Genetics (specified analyses) are not evaluated in this study.
8.5.2. Retained Research Samples for Genetics
A 4 mL blood sample optimized for DNA isolation Prep D1 will be collected according to 
the SoA, as local regulations and IRBs/ECs allow.
Retained Research Samples may be used for research related to the study intervention(s). 
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 Lab Manual.
8.6. Biomarkers
Biomarkers are not evaluated in this study.
8.7. Immunogenicity Assessments
Immunogenicity assessments are not included in this study.
8.8. Health Economics
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study.
9. STATISTICAL CONSIDERATIONS
Detailed methodology for summary and statistical analyses of the data collected in this study 
is outlined here and further detailed in 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
The alternative hypothesis of bioequivalence (H1: L <=T - R <=U), and the null 
hypothesis of inequivalence (Ho: T - R <L or T - R >U) can be expressed as the 
following 2 separate one-sided hypotheses: 
HoA: T - R <L
H1A: L <=T - R
HoB: T - R >U
H1B: T - R <=U

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where T and R represent the average bioavailability on a log scale for the Test and 
Reference products respectively and [L, U] defines the bioequivalence range.
Bioequivalence of the Test treatment to Reference treatment will be concluded if the 
90% confidence intervals for the ratios of adjusted geometric means for prazosin AUClast and 
Cmax fall entirely within the acceptance region of (80%, 125%).
9.2. Analysis Sets
For purposes of analysis, the following analysis sets are defined:
Participant Analysis 
Set
Description
Enrolled/Randomly 
assigned to study 
intervention
Participants will be randomized into the study provided they 
have satisfied all participant eligibility criteria.
PK concentration 
population
All participants randomized and treated who have at least 1 
concentration in at least 1 treatment period.
Safety
All participants randomly assigned to study intervention and 
who take at least 1 dose of investigational product.
9.3. Statistical Analyses
The SAP will be developed and finalized before any analyses are performed and will 
describe the analyses and procedures for accounting for missing, unused, and spurious data.
This section is a summary of the planned statistical analyses of the primary and secondary 
endpoints.
9.3.1. Primary Endpoint(s)
9.3.1.1. Determination of Pharmacokinetic Parameters
Pharmacokinetic parameters will be derived from the concentration-time profiles as shown in 
Table 5.

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Table 5.
PK Parameters
Parameter
Definition
Method of Determination
AUClast
Area under the plasma 
concentration-time curve from 
time zero to the time of the last 
quantifiable concentration (Clast).
Linear-log trapezoidal method.
AUCinf
Area under the plasma 
concentration-time curve from 
time zero extrapolated to infinite 
time.
AUClast + (Clast*/kel),
where Clast* is the predicted 
plasma concentration at the last 
quantifiable time point estimated 
from the log-linear regression 
analysis.
Cmax
Maximum plasma concentration.
Observed directly from data.
Tmax
Time to first occurrence of Cmax.
Observed directly from data as 
time of first occurrence.
t½
Terminal elimination half-life.
Ln(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.
Actual PK sampling times will be used in the derivation of PK parameters.
9.3.2. Statistical Analysis of Pharmacokinetic Parameter
Pharmacokinetic and statistical analysis will be performed for prazosin. Data from 2 Cohorts 
will be analyzed separately.
The PK parameters AUClast, AUCinf, Cmax, Tmax, and t½ will be summarized descriptively by 
analyte and treatment. For AUClast, AUCinf and Cmax parameters, individual data and 
geometric mean will be plotted with box plots by analyte and treatment for each parameter.
Plasma concentration data will be listed and summarized descriptively by analyte, PK 
sampling time and treatment. Individual participant and summary profiles (mean and median) 
of the plasma concentration-time data will be plotted against analyte by treatment. Mean and 
median profiles will be presented on both linear-linear and log-linear scales. For summary 
statistic and summary (mean and median) plots by sampling time, the nominal PK sampling 
time will be used. For individual participant plots by time, the actual PK sampling time will 
be used.
Cohort 1:
Natural log transformed PK parameters (AUCinf, AUClast, and Cmax) will be analyzed using a 
mixed effect model with sequence, period and treatment as fixed effects and participant
within sequence as a random effect. Estimates of the adjusted mean differences 
(Test – Reference) and the corresponding 90% confidence intervals will be obtained from the 
model. The adjusted mean differences and the 90% confidence intervals for the differences 

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will be exponentiated to provide estimates of the ratio of adjusted geometric means 
(Test/Reference) and the 90% confidence intervals for the ratios.
For primary objective, bioequivalence of the Test treatments (Treatment B and Treatment C) 
relative to Reference treatment (Treatment A) will be concluded if the 90% confidence 
intervals for the ratio of adjusted geometric means of Test treatments (Treatment B and 
Treatment C) relative to Reference treatment (Treatment A) for AUCinf (if data permit), 
AUClast and Cmax fall wholly within (80%, 125%).
Cohort 2:
Natural log transformed PK parameters (AUCinf, AUClast, and Cmax) will be analyzed using a 
mixed effect model with sequence, period and treatment as fixed effects and participant
within sequence as a random effect. Estimates of the adjusted mean differences 
(Test – Reference) and the corresponding 90% confidence intervals will be obtained from the 
model. The adjusted mean differences and the 90% confidence intervals for the differences 
will be exponentiated to provide estimates of the ratio of adjusted geometric means 
(Test/Reference) and the 90% confidence intervals for the ratios.
For primary objective, bioequivalence of the Test treatment (Treatment E) relative to 
Reference treatment (Treatment D) will be concluded if the 90% confidence intervals (CI) 
for the ratio of adjusted geometric means of Treatment E (5 mg capsule, Ascoli) relative to 
Treatment D (5 mg capsule, Barceloneta) for AUCinf (if data permit), AUClast and Cmax, fall 
wholly within (80%, 125%).
9.3.3. Safety analyses
All safety analyses will be performed on the safety population.
The safety data will be described and summarized in accordance with the Sponsor’s Data 
Standards.
AEs, ECGs, BP, pulse rate, and safety laboratory data will be reviewed and summarized on 
an ongoing basis during the study to evaluate the safety of participants. Any clinical 
laboratory, ECG, BP, and pulse rate abnormalities of potential clinical concern will be 
described. Medical history and 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.
9.3.4. Other Analyse(s)
There are no other analyses included in this study.

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9.4. Interim Analyses
No formal interim analysis will be conducted for this study. As this is an open-label
study, the sponsor may conduct unblinded reviews of the data during the course of the study 
for the purpose of safety assessment, facilitating PK/PD modeling, and/or supporting clinical 
development. 
9.5. Sample Size Determination
Cohort 1:
A sample size of 30 participants will provide at least 95% power that the 90% confidence 
interval for the ratio of Test to Reference treatment for both AUClast and Cmax of prazosin, 
individually will lie within the acceptance region of (80%, 125%). Consequently, this study 
will have approximately 90% overall power to demonstrate bioequivalence of the Test 
treatment to the Reference treatment [ie, equivalence for both AUC and Cmax], where overall 
power for the study is based on the product of the individual powers of the parameters of 
interest. This estimate is based on the assumption that the true ratio between Test and 
Reference treatments for both AUClast and Cmax is 0.95 and also assumes within-participant
standard deviations of 0.198 for both loge AUClast and loge Cmax, as obtained from the 
literature.
To allow for dropouts, 36 participants will be enrolled in order to have 30 PK evaluable
participants. Dropouts for non-safety reasons may be replaced at the discretion of the sponsor 
and investigator.
Cohort 2:
A sample size of 32 participants will provide at least 95% power that the 90% confidence 
interval for the ratio of Test to Reference treatment for AUClast and Cmax of prazosin, 
individually, will lie within the acceptance region of (80%, 125%). Consequently, this study 
will have approximately 90% overall power to demonstrate bioequivalence of the Test 
treatment to the Reference treatment [ie, equivalence for both AUC and Cmax], where overall 
power for the study is based on the product of the individual powers of the parameters of 
interest. This estimate is based on the assumption that the true ratio between Test and 
Reference treatments for both AUClast and Cmax is 0.95 and also assumes within-participant
standard deviations of 0.198 for both loge AUClast and loge Cmax respectively, as obtained 
from the literature. 
To allow for dropouts, 36 participants will be enrolled in order to have 32 PK evaluable
participants. Dropouts for non-safety reasons may be replaced at the discretion of the sponsor 
and investigator.

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10. SUPPORTING DOCUMENTATION AND OPERATIONAL CONSIDERATIONS
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations
10.1.1. Regulatory and Ethical Considerations
This study will be conducted in accordance with the protocol and with the following:

Consensus ethical principles derived from international guidelines, including the 
Declaration of Helsinki and CIOMS International Ethical Guidelines;

Applicable ICH GCP guidelines;

Applicable laws and regulations, including applicable privacy laws.
The protocol, protocol amendments, ICD, SRSD(s), and other relevant documents 
(eg, advertisements) must be reviewed and approved by the sponsor, submitted to an IRB/EC 
by the investigator, and reviewed and approved by the IRB/EC before the study is initiated.
Any amendments to the protocol will require IRB/EC approval before implementation of 
changes made to the study design, except for changes necessary to eliminate an immediate 
hazard to study participants.
Protocols and any substantial amendments to the protocol will require health authority 
approval prior to initiation except for changes necessary to eliminate an immediate hazard to 
study participants.
The investigator will be responsible for the following:

Providing written summaries of the status of the study to the IRB/EC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/EC;

Notifying the IRB/EC of SAEs or other significant safety findings as required by 
IRB/EC procedures;

Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 CFR, ICH GCP guidelines, the IRB/EC, European regulation 
536/2014 for clinical studies (if applicable), European Medical Device Regulation 
2017/745 for clinical device research (if applicable), and all other applicable local 
regulations.
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the Protocol or ICH GCP
In the event of any prohibition or restriction imposed (ie, clinical hold) by an applicable 
regulatory authority in any area of the world, or if the investigator is aware of any new 
information that might influence the evaluation of the benefits and risks of the study 
intervention, Pfizer should be informed immediately.

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In addition, the investigator will inform Pfizer immediately of any urgent safety measures 
taken by the investigator to protect the study participants against any immediate hazard, and 
of any serious breaches of this protocol or of the ICH GCP guidelines that the investigator 
becomes aware of.
10.1.2. Financial Disclosure
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, including the 
risks and benefits, to the participant or his/her legally authorized representative and answer 
all questions regarding the study. The participant or his/her legally authorized representative 
should be given sufficient time and opportunity to ask questions and to decide whether or not 
to participate in the trial.
Participants must be informed that their participation is voluntary. Participants or their 
legally authorized representative will be required to sign a statement of informed consent that 
meets the requirements of 21 CFR 50, local regulations, ICH guidelines, privacy and data 
protection requirements, where applicable, and the IRB/EC or study center.
The investigator must ensure that each study participant or his or her legally authorized 
representative is fully informed about the nature and objectives of the study, the sharing of 
data related to the study, and possible risks associated with participation, including the risks 
associated with the processing of the participant’s personal data. 
The participant or his or her legally authorized representative 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 or his or her 
legally authorized representative.
The participant or his or her legally authorized representative 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 or his or her legally 
authorized representative 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.

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The medical record must include a statement that written informed consent was obtained 
before the participant was enrolled in the study and the date on which the written consent was 
obtained. The authorized person obtaining the informed consent must also sign the ICD.
Participants or his or her legally authorized representative 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 or the participant’s legally 
authorized representative.
10.1.4. Data Protection
All parties will comply with all applicable laws, including laws regarding the implementation 
of organizational and technical measures to ensure protection of participant data.
Participants’ personal data will be stored at the study site in encrypted electronic and/or paper 
form and will be password-protected or secured in a locked room to ensure that only 
authorized study staff have access. The study site will implement appropriate technical and 
organizational measures to ensure that the personal data can be recovered in the event of 
disaster. In the event of a potential personal data breach, the study site will be responsible for 
determining whether a personal data breach has in fact occurred and, if so, providing breach 
notifications as required by law.
To protect the rights and freedoms of participants with regard to the processing of personal 
data, participants will be assigned a single, participant-specific numerical code. Any 
participant records or data sets that are transferred to the sponsor will contain the numerical 
code; participant names will not be transferred. All other identifiable data transferred to the 
sponsor will be identified by this single, participant-specific code. The study site will 
maintain a confidential list of participants who participated in the study, linking each 
participant’s numerical code to his or her actual identity and medical record ID. In case of 
data transfer, the sponsor will protect the confidentiality of participants’ personal data 
consistent with the clinical study agreement and applicable privacy laws.
10.1.5. Committees Structure
10.1.5.1. Data Monitoring Committee 
This study will not use a DMC.
10.1.6. Dissemination of Clinical Study Data
Pfizer fulfills its commitment to publicly disclose clinical study results through posting the 
results of studies on www.clinicaltrials.gov (ClinicalTrials.gov), the EudraCT, and/or 
www.pfizer.com, and other public registries in accordance with applicable local 
laws/regulations. In addition, Pfizer reports study results outside of the requirements of local 
laws/regulations pursuant to its SOPs.

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In all cases, study results are reported by Pfizer in an objective, accurate, balanced, and 
complete manner and are reported regardless of the outcome of the study or the country in 
which the study was conducted.
www.clinicaltrials.gov
Pfizer posts clinical trial results on www.clinicaltrials.gov for Pfizer-sponsored interventional 
studies (conducted in patients) that evaluate the safety and/or efficacy of a product, 
regardless of the geographical location in which the study is conducted. These results are 
submitted for posting in accordance with the format and timelines set forth by US law.
EudraCT
Pfizer posts clinical trial results on EudraCT for Pfizer-sponsored interventional studies in 
accordance with the format and timelines set forth by EU requirements.
www.pfizer.com
Pfizer posts public disclosure synopses (CSR synopses in which any data that could be used 
to identify individual participants have been removed) on www.pfizer.com for 
Pfizer-sponsored interventional studies at the same time the corresponding study results are
posted to www.clinicaltrials.gov.
Documents within marketing authorization packages/submissions
Pfizer complies with the European Union Policy 0070, the proactive publication of clinical 
data to the EMA website. Clinical data, under Phase 1 of this policy, includes clinical 
overviews, clinical summaries, CSRs, and appendices containing the protocol and protocol 
amendments, sample CRFs, and statistical methods. Clinical data, under Phase 2 of this 
policy, includes the publishing of individual participant data. Policy 0070 applies to new 
marketing authorization applications submitted via the centralized procedure since 
01 January 2015 and applications for line extensions and for new indications submitted via 
the centralized procedure since 01 July 2015.
Data sharing
Pfizer provides researchers secure access to patient-level data or full CSRs for the purposes 
of “bona-fide scientific research” that contributes to the scientific understanding of the 
disease, target, or compound class. Pfizer will make data from these trials available 
24 months after study completion. Patient-level data will be anonymized in accordance with 
applicable privacy laws and regulations. CSRs will have personally identifiable information 
redacted.
Data requests are considered from qualified researchers with the appropriate competencies to 
perform the proposed analyses. Research teams must include a biostatistician. Data will not 

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be provided to applicants with significant conflicts of interest, including individuals 
requesting access for commercial/competitive or legal purposes.
10.1.7. Data Quality Assurance
All participant data relating to the study will be recorded on printed or electronic CRF unless 
transmitted to the sponsor or designee electronically (eg, laboratory data). The investigator is 
responsible for verifying that data entries are accurate and correct by physically or 
electronically signing the CRF.
Guidance on completion of CRFs will be provided in the CRF Completion Requirements 
document.
The investigator must ensure that the CRFs are securely stored at the study site in encrypted 
electronic and/or paper form and are password-protected or secured in a locked room to 
prevent access by unauthorized third parties.
The investigator must permit study-related monitoring, audits, IRB/EC review, and 
regulatory agency inspections and provide direct access to source data documents. This 
verification may also occur after study completion. It is important that the investigator(s) and 
their relevant personnel are available during the monitoring visits and possible audits or 
inspections and that sufficient time is devoted to the process.
Monitoring details describing strategy, including definition of study critical data items and 
processes (eg, risk-based initiatives in operations and quality, such as risk management and 
mitigation strategies and analytical risk-based monitoring), methods, responsibilities, and 
requirements, including handling of noncompliance issues and monitoring techniques 
(central, virtual, or on-site monitoring), are provided in the data management plan and 
monitoring plan maintained and utilized by the sponsor or designee.
The sponsor or designee is responsible for the data management of this study, including 
quality checking of the data.
Records and documents, including signed ICDs, pertaining to the conduct of this study must 
be retained by the investigator for 15 years after study completion unless local regulations or 
institutional policies require a longer retention period. No records may be destroyed during 
the retention period without the written approval of the sponsor. No records may be 
transferred to another location or party without written notification to the sponsor. The 
investigator must ensure that the records continue to be stored securely for as long as they are 
maintained.
When participant data are to be deleted, the investigator will ensure that all copies of such 
data are promptly and irrevocably deleted from all systems.
The investigator(s) will notify the sponsor or its agents immediately of any regulatory 
inspection notification in relation to the study. Furthermore, the investigator will cooperate 
with the sponsor or its agents to prepare the investigator site for the inspection and will allow 

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the sponsor or its agent, whenever feasible, to be present during the inspection. The 
investigator site and investigator will promptly resolve any discrepancies that are identified 
between the study data and the participant's medical records. The investigator will promptly 
provide copies of the inspection findings to the sponsor or its agent. Before response 
submission to the regulatory authorities, the investigator will provide the sponsor or its 
agents with an opportunity to review and comment on responses to any such findings.
10.1.8. Source Documents
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected. Source documents are filed at the investigator site.
Data reported on the CRF or entered in the eCRF that are from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
investigator may need to request previous medical records or transfer records, depending on 
the study. Also, current medical records must be available.
In this study, the CRF will serve as the source document. A document must be available at 
the investigative site that identifies those data that will be recorded on the CRF and for which 
the CRF will be the source document.
Definition of what constitutes source data and its origin can be found in data collection 
guidelines, which is maintained by the sponsor.
Description of the use of the computerized system is documented in the Data Management 
Plan, which is maintained by the sponsor.
The investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF.
Study monitors will perform ongoing source data verification to confirm that data entered 
into the CRF by authorized site personnel are accurate, complete, and verifiable from source 
documents; that the safety and rights of participants are being protected; and that the study is 
being conducted in accordance with the currently approved protocol and any other study 
agreements, ICH GCP guidelines, and all applicable regulatory requirements.
10.1.9. Study and Site Start and Closure
The study start date is the date on which the clinical study will be open for recruitment of 
participants.
The first act of recruitment is the date of the first participant’s first visit and will be the study 
start date.
The sponsor designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of the sponsor. Study sites will be closed upon study 

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

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sponsor will support publication of multicenter studies only in their entirety and not as 
individual site data. In this case, a coordinating investigator will be designated by mutual 
agreement.
Authorship of publications for the overall study results will be determined by mutual 
agreement and in line with International Committee of Medical Journal Editors authorship 
requirements. 
If publication is addressed in the clinical study agreement, the publication policy set out in 
this section will not apply.
10.1.11. Sponsor’s Qualified Medical Personnel
The contact information for the sponsor's appropriately qualified medical personnel for the 
study is documented in the study contact list located in the SToD system.
To facilitate access to appropriately qualified medical personnel for study-related medical 
questions or problems, participants are provided with an Emergency Contact Card (ECC) at 
the time of informed consent. The ECC contains, at a minimum, (a) protocol and study 
intervention identifiers, (b) participant’s study identification number, (c) site emergency 
phone number active 24 hours/day, 7 days per week, and (d) Pfizer Call Center number.
The ECC is intended to augment, not replace, the established communication pathways 
between the investigator, site staff, and study team. The ECC is to be used by healthcare 
professionals not involved in the research study only, as a means of reaching the investigator 
or site staff related to the care of a participant. The Pfizer Call Center number should only be 
used when the investigator and site staff cannot be reached. The Pfizer Call Center number is 
not intended for use by the participant directly; if a participant calls that number directly, 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 6.
Protocol-Required Safety Laboratory Assessments
Hematology
Chemistry
Urinalysis
Other
Hemoglobin
Hematocrit
RBC count
MCV
MCH
MCHC
Platelet count
WBC count
Total neutrophils 
(Abs)
Eosinophils (Abs)
Monocytes (Abs)
Basophils (Abs)
Lymphocytes (Abs)
BUN and creatinine
Glucose (fasting)
Calcium
Sodium
Potassium
Chloride
Total CO2 (bicarbonate)
AST, ALT
Total bilirubin
Alkaline phosphatase
Uric acid
Albumin
Total protein
Local Dipstick:
pH
Glucose (qual)
Protein (qual)
Blood (qual)
Ketones
Nitrites
Leukocyte esterase
Urobilinogen
Urine bilirubin
Urine drug 
screeninga
Laboratory:
Microscopy and 
Cultureb
COVID-19 testing
At screening only:

FSHc

Pregnancy test (-hCG)d

Hepatitis B surface 
antigen

Hepatitis C antibody

Human 
immunodeficiency virus
a.
The minimum requirement for drug screening includes cocaine, THC, opiates/opioids, 
benzodiazepines, and amphetamines (others are site and study specific).
b.
Only if urine dipstick is positive for blood, protein, nitrites, or leukocyte esterase.
c.
For confirmation of postmenopausal status only.
d.
Local urine testing will be standard for the protocol unless serum testing is required by local regulation 
or IRB/EC. Serum or urine -hCG for female participants of childbearing potential.
The investigator must review the laboratory report, document this review, and record any 
clinically relevant changes occurring during the study in the AE section of the CRF.

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10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-Up, and Reporting
10.3.1. Definition of AE
AE Definition

An AE is any untoward medical occurrence in a patient or clinical study 
participant, temporally associated with the use of study intervention, whether or 
not considered related to the study intervention.

Note: An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease (new or exacerbated) 
temporally associated with the use of study intervention.
Events Meeting the AE Definition

Any abnormal laboratory test results (hematology, clinical chemistry, or 
urinalysis) or other safety assessments (eg, ECG, radiological scans, vital sign 
measurements), including those that worsen from baseline, considered clinically 
significant in the medical and scientific judgment of the investigator. Any 
abnormal laboratory test results that meet any of the conditions below must be 
recorded as an AE:

Is associated with accompanying symptoms;

Requires additional diagnostic testing or medical/surgical intervention;

Leads to a change in study dosing (outside of any protocol-specified dose 
adjustments) or discontinuation from the study, significant additional 
concomitant drug treatment, or other therapy.

Exacerbation of a chronic or intermittent preexisting condition, including either 
an increase in frequency and/or intensity of the condition.

New condition detected or diagnosed after study intervention administration,
even though it may have been present before the start of the study.

Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction.

Signs, symptoms, or the clinical sequelae of a suspected overdose of either study 
intervention or a concomitant medication. Overdose per se will not be reported as 
an AE or SAE unless it is an intentional overdose taken with possible 
suicidal/self-harming intent. Such overdoses should be reported regardless of 
sequelae.

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Events NOT Meeting the AE Definition

Any clinically significant abnormal laboratory findings or other abnormal safety 
assessments that are associated with the underlying disease, unless judged by the 
investigator to be more severe than expected for the participant’s condition.

The disease/disorder being studied or expected progression, signs, or symptoms 
of the disease/disorder being studied, unless more severe than expected for the 
participant’s condition.

Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that 
leads to the procedure is the AE.

Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital).

Anticipated day-to-day fluctuations of preexisting disease(s) or condition(s) 
present or detected at the start of the study that do not worsen.
10.3.2. Definition of an SAE
An SAE is defined as any untoward medical occurrence that, at any dose, meets one 
or more of the criteria listed below:
a. Results in death
b. Is life-threatening
The term “life-threatening” in the definition of “serious” refers to an event in which 
the participant was at risk of death at the time of the event. It does not refer to an 
event that hypothetically might have caused death if it were more severe.
c.
Requires inpatient hospitalization or prolongation of existing hospitalization
In general, hospitalization signifies that the participant has been admitted (usually 
involving at least an overnight stay) at the hospital or emergency ward for 
observation and/or treatment that would not have been appropriate in the physician’s 
office or outpatient setting. Complications that occur during hospitalization are AEs. 
If a complication prolongs hospitalization or fulfills any other serious criteria, the 
event is serious. When in doubt as to whether “hospitalization” occurred or was 
necessary, the AE should be considered serious.
Hospitalization for elective treatment of a preexisting condition that did not worsen 
from baseline is not considered an AE.

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d. Results in persistent or significant disability/incapacity

The term disability means a substantial disruption of a person’s ability to conduct 
normal life functions.

This definition is not intended to include experiences of relatively minor medical 
significance, such as uncomplicated headache, nausea, vomiting, diarrhea, 
influenza, and accidental trauma (eg, sprained ankle), that may interfere with or 
prevent everyday life functions but do not constitute a substantial disruption.
e.
Is a congenital anomaly/birth defect
f.
Is a suspected transmission via a Pfizer product of an infectious agent, 
pathogenic or non-pathogenic, is considered serious.
The event may be suspected from clinical symptoms or laboratory findings 
indicating an infection in a participant exposed to a Pfizer product. The terms 
“suspected transmission” and “transmission” are considered synonymous. These 
cases are considered unexpected and handled as serious expedited cases by 
pharmacovigilance personnel. Such cases are also considered for reporting as 
product defects, if appropriate.
g. Other situations:

Medical or scientific judgment should be exercised by the investigator in 
deciding whether SAE reporting is appropriate in other situations, such as 
significant medical events that may jeopardize the participant or may require 
medical or surgical intervention to prevent one of the other outcomes listed in the 
above definition. These events should usually be considered serious.

Examples of such events include invasive or malignant cancers, intensive 
treatment in an emergency room or at home for allergic bronchospasm, blood 
dyscrasias or convulsions that do not result in hospitalization, or development of 
drug dependency or drug abuse.
10.3.3. Recording/Reporting and Follow-Up of AEs and/or SAEs During the Active 
Collection Period
AE and SAE Recording/Reporting
The table below summarizes the requirements for recording AEs on the CRF and for 
reporting SAEs on the CT SAE Report Form to Pfizer Safety throughout the active 
collection period. These requirements are delineated for 3 types of events: (1) SAEs; (2) 
nonserious AEs; and (3) exposure to the study intervention under study during 
pregnancy or breastfeeding, and occupational exposure. 

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It should be noted that the CT SAE Report Form for reporting of SAE information is not 
the same as the AE page of the CRF. When the same data are collected, the forms must 
be completed in a consistent manner. AEs should be recorded using concise medical 
terminology and the same AE term should be used on both the CRF and the CT SAE 
Report Form for reporting of SAE information.
Safety Event
Recorded on the CRF
Reported on the CT SAE 
Report Form to Pfizer 
Safety Within 24 Hours 
of Awareness
SAE
All
All
Nonserious AE
All
None
Exposure to the study 
intervention under study 
during pregnancy or 
breastfeeding
All AEs/SAEs associated 
with exposure during 
pregnancy or breastfeeding
Note: Instances of EDP or 
EDB not associated with an 
AE or SAE are not captured 
in the CRF.
All instances of EDP are 
reported (whether or not 
there is an associated 
SAE)*
All instances of EDB are 
reported (whether or not 
there is an associated 
SAE). **
Environmental or 
occupational exposure 
to the product under 
study to a non-
participant (not 
involving EDP or EDB).
None. Exposure to a study 
non-participant is not 
collected on the CRF.
The exposure (whether or 
not there is an associated 
AE or SAE) must be 
reported.***
*
EDP (with or without an associated AE or SAE): any pregnancy information is reported to 
Pfizer Safety using CT SAE Report Form and EDP Supplemental Form; if the EDP is 
associated with an SAE, then the SAE is reported to Pfizer Safety using the CT SAE 
Report Form. 
** EDB is reported to Pfizer Safety using the CT SAE Report Form which would also include 
details of any SAE that might be associated with the EDB. 
*** Environmental or Occupational exposure: AEs or SAEs associated with occupational 
exposure are reported to Pfizer Safety using the CT SAE Report Form. 

When an AE or SAE occurs, it is the responsibility of the investigator to review 
all documentation (eg, hospital progress notes, laboratory reports, and diagnostic 
reports) related to the event.

The investigator will then record all relevant AE or SAE information in the CRF.

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
It is not acceptable for the investigator to send photocopies of the participant’s 
medical records to Pfizer Safety in lieu of completion of the CT SAE Report 
Form/AE or SAE CRF page.

There may be instances when copies of medical records for certain cases are 
requested by Pfizer Safety. In this case, all participant identifiers, with the 
exception of the participant number, will be redacted on the copies of the medical 
records before submission to Pfizer Safety.

The investigator will attempt to establish a diagnosis of the event based on signs, 
symptoms, and/or other clinical information. Whenever possible, the diagnosis 
(not the individual signs/symptoms) will be documented as the AE or SAE.
Assessment of Intensity
The investigator will make an assessment of intensity for each AE and SAE reported 
during the study and assign it to 1 of the following categories: 

Mild: Asymptomatic or mild symptoms; clinical or diagnostic observations only; 
intervention not indicated.

Moderate: Minimal, local or noninvasive intervention indicated; limiting age-
appropriate instrumental ADL. Instrumental ADL refers to preparing meals, 
shopping for groceries or clothes, using the telephone, managing money, etc.

Severe: Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling, limiting 
self care ADL. Self care ADL refers to bathing, dressing and undressing, feeding 
self, using the toilet, taking medications, and not bedridden.
An event is defined as “serious” when it meets at least 1 of the predefined outcomes as 
described in the definition of an SAE, NOT when it is rated as severe.
Assessment of Causality

The investigator is obligated to assess the relationship between study intervention 
and each occurrence of each AE or SAE. The investigator will use clinical 
judgment to determine the relationship.

A “reasonable possibility” of a relationship conveys that there are facts, 
evidence, and/or arguments to suggest a causal relationship, rather than a 
relationship cannot be ruled out.

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
Alternative causes, such as underlying disease(s), concomitant therapy, and other 
risk factors, as well as the temporal relationship of the event to study intervention 
administration, will be considered and investigated.

The investigator will also consult the IB and/or product information, for 
marketed products, in his/her assessment.

For each AE or SAE, the investigator must document in the medical notes that 
he/she has reviewed the AE or SAE and has provided an assessment of causality.

There may be situations in which an SAE has occurred and the investigator has 
minimal information to include in the initial report to the sponsor. However, it is 
very important that the investigator always make an assessment of causality 
for every event before the initial transmission of the SAE data to the 
sponsor.

The investigator may change his/her opinion of causality in light of follow-up 
information and send an SAE follow-up report with the updated causality 
assessment.

The causality assessment is one of the criteria used when determining regulatory 
reporting requirements.

If the investigator does not know whether or not the study intervention caused the 
event, then the event will be handled as “related to study intervention” for 
reporting purposes, as defined by the sponsor. In addition, if the investigator 
determines that an SAE is associated with study procedures, the investigator 
must record this causal relationship in the source documents and CRF, and report 
such an assessment in the dedicated section of the CT SAE Report Form and in 
accordance with the SAE reporting requirements.
Follow-Up of AEs and SAEs

The investigator is obligated to perform or arrange for the conduct of 
supplemental measurements and/or evaluations, as medically indicated or as 
requested by the sponsor, to elucidate the nature and/or causality of the AE or 
SAE as fully as possible. This may include additional laboratory tests or 
investigations, histopathological examinations, or consultation with other 
healthcare providers.

If a participant dies during participation in the study or during a recognized 
follow-up period, the investigator will provide Pfizer Safety with a copy of any 
postmortem findings, including histopathology.

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
New or updated information will be recorded in the originally submitted 
documents.

The investigator will submit any updated SAE data to the sponsor within 24 
hours of receipt of the information.
10.3.4. Reporting of SAEs
SAE Reporting to Pfizer Safety via an Electronic Data Collection Tool

The primary mechanism for reporting an SAE to Pfizer Safety will be the 
electronic data collection tool.

If the electronic system is unavailable, then the site will use the paper SAE data 
collection tool (see next section) to report the event within 24 hours.

The site will enter the SAE data into the electronic system as soon as the data
become available.

After the study is completed at a given site, the electronic data collection tool 
will be taken off-line to prevent the entry of new data or changes to existing data.

If a site receives a report of a new SAE from a study participant or receives 
updated data on a previously reported SAE after the electronic data collection 
tool has been taken off-line, then the site can report this information on a paper 
SAE form (see next section) or to Pfizer Safety by telephone.
SAE Reporting to Pfizer Safety via CT SAE Report Form

Facsimile transmission of the CT SAE Report Form is the preferred method to 
transmit this information to Pfizer Safety.

In circumstances when the facsimile is not working, notification by telephone is 
acceptable with a copy of the CT SAE Report Form sent by overnight mail or 
courier service.

Initial notification via telephone does not replace the need for the investigator to 
complete and sign the CT SAE Report Form pages within the designated 
reporting time frames.

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10.4. Appendix 4: Contraceptive and Barrier Guidance
10.4.1. Male Participant Reproductive Inclusion Criteria
Male participants are eligible to participate if they agree to the following requirements during 
the intervention period and for at least 8 days after the last dose of study intervention, which
corresponds to the time needed to eliminate reproductive safety risk of the study 
intervention(s):

Refrain from donating sperm.
PLUS either:

Be abstinent from heterosexual intercourse with a female of childbearing potential as 
their preferred and usual lifestyle (abstinent on a long-term and persistent basis) and 
agree to remain abstinent.
OR

Must agree to use contraception/barrier as detailed below:

Agree to use a male condom and should also be advised of the benefit for a 
female partner to use a highly effective method of contraception as a condom may
break or leak when having sexual intercourse with a woman of childbearing 
potential who is not currently pregnant.

In addition to male condom use, a highly effective method of contraception may be 
considered in WOCBP partners of male participants (refer to the list of highly 
effective methods below in Section 10.4.4).
10.4.2. Female Participant Reproductive Inclusion Criteria
A female participant is eligible to participate if she is not pregnant or breastfeeding, and at 
least 1 of the following conditions applies:

Is not a WOCBP (see definitions below in Section 10.4.3).
OR

Is a WOCBP and using a contraceptive method that is highly effective (with a failure 
rate of <1% per year), with low user dependency, as described below during the 
intervention period and for at least 28 days after the last dose of study intervention,
which corresponds to the time needed to eliminate any reproductive safety risk of the 
study intervention(s). The investigator should evaluate the effectiveness of the 
contraceptive method in relationship to the first dose of study intervention.

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The investigator is responsible for review of medical history, menstrual history, and recent 
sexual activity to decrease the risk for inclusion of a woman with an early undetected 
pregnancy. 
10.4.3. Woman of Childbearing Potential
A woman is considered fertile following menarche and until becoming postmenopausal 
unless permanently sterile (see below).
If fertility is unclear (eg, amenorrhea in adolescents or athletes) and a menstrual cycle cannot 
be confirmed before the first dose of study intervention, additional evaluation should be 
considered.
Women in the following categories are not considered WOCBP:
1. Premenopausal female with 1 of the following:

Documented hysterectomy;

Documented bilateral salpingectomy;

Documented bilateral oophorectomy.
For individuals with permanent infertility due to an alternate medical cause other than 
the above, (eg, mullerian agenesis, androgen insensitivity), investigator discretion 
should be applied to determining study entry.
Note: Documentation for any of the above categories can come from the site 
personnel’s review of the participant’s medical records, medical examination, or 
medical history interview. The method of documentation should be recorded in the 
participant’s medical record for the study.
2. Postmenopausal female.

A postmenopausal state is defined as no menses for 12 months without an 
alternative medical cause. In addition:

A high FSH level in the postmenopausal range must be used to confirm a 
postmenopausal state in women under 60 years old and not using hormonal 
contraception or HRT. 

A female on HRT and whose menopausal status is in doubt will be required to 
use one of the nonestrogen hormonal highly effective contraception methods 
if they wish to continue their HRT during the study. Otherwise, they must 
discontinue HRT to allow confirmation of postmenopausal status before study 
enrollment.

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10.4.4. Contraception Methods
Contraceptive use by men or women should be consistent with local availability/regulations 
regarding the use of contraceptive methods for those participating in clinical trials.
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 (eg, bilateral tubal ligation).
5. Vasectomized partner.

A vasectomized partner is a highly effective contraceptive method provided that 
the partner is the sole sexual partner of the WOCBP and the absence of sperm has 
been confirmed. If not, an additional highly effective method of contraception 
should be used. The spermatogenesis cycle is approximately 90 days.
Highly Effective Methods That Are User Dependent
6. Combined (estrogen- and progestogen-containing) hormonal contraception associated 
with inhibition of ovulation.

Oral;

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 

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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 study intervention or study interventions of this class to 
understand treatments for the disease(s) under study or the disease(s) themselves.

The results of genetic analyses may be reported in the CSR or in a separate study 
summary, or may be used for internal decision making without being included in a 
study report.

The sponsor will store the DNA samples in a secure storage space with adequate 
measures to protect confidentiality. 

The samples will be retained as indicated:

Retained samples will be stored indefinitely or for another period as per local 
requirements.

Participants may withdraw their consent for the storage and/or use of their Retained 
Research Samples at any time by making a request to the investigator; in this case, 
any remaining material will be destroyed. Data already generated from the samples 
will be retained to protect the integrity of existing analyses.

Samples for genetic research will be labeled with a code. The key between the code 
and the participant’s personally identifying information (eg, name, address) will be 
held securely at the study site.

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10.6. Appendix 6: Liver Safety: Suggested Actions and Follow-Up Assessments 
Potential Cases of Drug-Induced Liver Injury
Humans exposed to a drug who show no sign of liver injury (as determined by elevations in 
transaminases) are termed “tolerators,” while those who show transient liver injury but adapt 
are termed “adaptors.” In some participants, transaminase elevations are a harbinger of a 
more serious potential outcome. These participants fail to adapt and therefore are 
"susceptible" to progressive and serious liver injury, commonly referred to as DILI.
Participants who experience a transaminase elevation above 3 × ULN should be monitored 
more frequently to determine if they are “adaptors” or are “susceptible.”
LFTs are not required as a routine safety monitoring procedure in this study. However, 
should an investigator deem it necessary to assess LFTs because a participant presents with 
clinical signs/symptoms, such LFT results should be managed and followed as described 
below.
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).

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
Preexisting values of TBili above the normal range: TBili level increased from 
baseline value by an amount of at least 1 × ULN or if the value reaches 
>3 × ULN (whichever is smaller).
Rises in AST/ALT and TBili separated by more than a few weeks should be assessed 
individually based on clinical judgment; any case where uncertainty remains as to whether it 
represents a potential Hy’s law case should be reviewed with the sponsor. 
The participant should return to the investigator site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the abnormal results. This evaluation should 
include laboratory tests, detailed history, and physical assessment. 
In addition to repeating measurements of AST and ALT and TBili for suspected Hy’s law 
cases, additional laboratory tests should include albumin, CK, direct and indirect bilirubin, 
GGT, PT/INR, total bile acids, and alkaline phosphatase. Consideration should also be given 
to drawing a separate tube of clotted blood and an anticoagulated tube of blood for further 
testing, as needed, for further contemporaneous analyses at the time of the recognized initial 
abnormalities to determine etiology. A detailed history, including relevant information, such 
as review of ethanol, acetaminophen/paracetamol (either by itself or as a coformulated 
product in prescription or over-the-counter medications), recreational drug, or supplement 
(herbal) use and consumption, family history, sexual history, travel history, history of contact 
with a jaundiced person, surgery, blood transfusion, history of liver or allergic disease, and 
potential occupational exposure to chemicals, should be collected. Further testing for acute 
hepatitis A, B, C, D, and E infection, liver imaging (eg, biliary tract), and collection of serum 
samples for acetaminophen/paracetamol drug and/or protein adduct levels may be warranted. 
All cases demonstrated on repeat testing as meeting the laboratory criteria of AST/ALT and 
TBili elevation defined above should be considered potential DILI (Hy’s law) cases if no 
other reason for the 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).

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

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10.8. Appendix 8: Alternative Measures During Public Emergencies
The alternative study measures described in this section are to be followed during public 
emergencies, including the COVID-19 pandemic. This appendix applies for the duration of 
the COVID-19 pandemic globally and will become effective for other public emergencies 
only upon written notification from Pfizer. 
Use of these alternative study measures are expected to cease upon the return of business as 
usual circumstances (including the lifting of any quarantines and travel bans/advisories). 
10.8.1. Study Intervention
If the safety of a trial participant is at risk because they cannot complete required evaluations 
or adhere to critical mitigation steps, then discontinuing that participant from study 
intervention must be considered.
10.8.2. Adverse Events and Serious Adverse Events
If a participant has COVID-19 during the study, this should be reported as an AE or SAE and 
appropriate medical intervention provided. 
It is recommended that the investigator discuss temporary or permanent discontinuation of 
study intervention with the study medical monitor. 

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10.10. Appendix 9: Abbreviations
The following is a list of abbreviations that may be used in the protocol.
Abbreviation
Term
Abs
absolute
ADL
activities of daily living
AE
adverse event
ALT
alanine aminotransferase
AST
aspartate aminotransferase
AUC
area under the curve
AUClast
area under the plasma concentration-time curve from time zero to 
the time of the last quantifiable concentration
AUCinf
area under the plasma concentration-time curve from time zero 
extrapolated to infinite time
AV
atrioventricular
BE
bioequivalence
-hCG
beta-human chorionic gonadotropin
BMI
body mass index
BP
blood pressure
bpm
beats per minute
BUN
blood urea nitrogen
CFR
Code of Federal Regulations
CI
confidence interval
CIOMS
Council for International Organizations of Medical Sciences
CK
creatine kinase
Cmax
maximum plasma concentration
CO2
carbon dioxide (bicarbonate)
COVID-19
coronavirus disease 2019
CRF
case report form
CRO
contract research organization
CRU
clinical research unit
CSR
clinical study report
CT
clinical trial
DC
discontinuation
DCT
data collection tool
DILI
drug-induced liver injury
DMC
data monitoring committee
DNA
deoxyribonucleic acid
EC
ethics committee
ECC
Emergency Contact Card
ECG
electrocardiogram
eCRF
electronic case report form
EDB
exposure during birth

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Abbreviation
Term
EDP
exposure during pregnancy
EMA
European Medicines Agency
EU
European Union
EudraCT
European Clinical Trials Database
f2
similarity factor
FDA
Food and Drug Administration
FSH
follicle-stimulating hormone
GCP
Good Clinical Practice
GGT
gamma-glutamyl transferase
HBcAb
hepatitis B core antibody
HBsAb
hepatitis B surface antibody
HBsAg 
hepatitis B surface antigen
HCl
hydrochloride
HCVAb
hepatitis C antibody
HIV
human immunodeficiency virus
HRT
hormone replacement therapy
IB
investigator’s brochure
ICD
informed consent document
ICH
International Council for Harmonisation
IND
investigational new drug application
INR
international normalized ratio
IP
investigational product
IRB
institutional review board
IV
intravenous
LBBB
left bundle branch block
LFT
liver function test
MCH
mean corpuscular hemoglobin
MCHC
mean corpuscular hemoglobin concentration
MCV
mean corpuscular volume
msec
millisecond
N
number of participants
PCR
polymerase chain reaction
PD
pharmacodynamic(s)
PK
pharmacokinetic(s)
PT
prothrombin time
PVC
premature ventricular complex 
QTc
corrected QT
QTcF
corrected QT (Fridericia method)
qual
qualitative
RBC
red blood cell
RNA
ribonucleic acid
SAE
serious adverse event

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Abbreviation
Term
SAP
statistical analysis plan
SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
SoA
schedule of activities
SOP
standard operating procedure
SRSD
single reference safety document
SToD
study team on demand
SUSAR
suspected unexpected serious adverse reaction
t½
terminal elimination half-life
TBili
total bilirubin
THC
tetrahydrocannabinol
Tmax
time to first occurrence of Cmax
ULN
upper limit of normal
US
United States
USPI
United States Package Insert
WBC
white blood cell
WOCBP
woman of childbearing potential

CP-012299, Prazosin Hydrochloride
A0281006
Final Protocol, 22 February 2021
PFIZER CONFIDENTIAL
Page 78
11. REFERENCES
1.
Minipress® Capsules (prazosin hydrochloride) For Oral Use [prescribing information]. 
New York, NY: Pfizer Inc; Jul 2009. Available from: 
https://www.pfizer.com/files/products/uspi_minipress.pdf. Accessed: 19 Feb 2019. 
2.
Vincent J, Meredith PA, Reid JL, et al. Clinical pharmacokinetics of prazosin – 1985
[abstract]. Clinical Pharmacokinetics. 1985;10: 144-154.
3.
Larochelle, P, du Souich P, Hamet P, el al. Prazosin plasma concentration and blood 
pressure reduction [abstract]. Hypertension. 1982;4(1): 93-101.
4.
US Food and Drug Administration. Draft Guidance on Prazosin Hydrochloride Oral 
Capsules. December 2016. Available from: 
https://www.accessdata.fda.gov/drugsatfda_docs/psg/Prazosin%20HCl_oral%20capsule
_RLD%2017442_RC12-16.pdf. Accessed: 19 Feb 2019
 
 
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