Final Full Clinical Study Report
Protocol C3941003

CLINICAL STUDY REPORT SYNOPSISSYNOPSIS
Study Title: A Phase 1, Randomized, Double-Blind, Vehicle-Controlled, Parallel Cohort
Study to Evaluate the Safety, Tolerability, Skin Irritation Potential and Pharmacokinetics ofMultiple-Dose, Topical Administration of PF-07038124 to Japanese Healthy Participants
Study Number: C3941003
Regulatory Agency or Public Disclosure Identifier Number: NCT04863417
Study Phase: Phase 1
Name of Study Intervention: PF-07038124
Name of Sponsor/Company: Pfizer Inc.
CSR Version and Report Date: Final, 06 Mar 2022
Number of Study Centers and Investigators:
Twelve participants were enrolled in this study. This study was conducted by principal
investigator at 1 center in Japan.
A list of study centers and investigators involved in this study is provided inAppendix 16.1.4.1.
Publications:NoneStudy Period:
The study was initiated on 30 June 2021 and completed on 09 September 2021. This study
was neither discontinued nor interrupted.
Rationale:
The purpose of this study was to evaluate the multiple-dose safety, tolerability, skin irritation
potential, and pharmacokinetics (PK) of PF-07038124 in Japanese healthy participants. The
data provided in this study support for clinical development in Japanese participants withatopic dermatitis and psoriasis.

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CLINICAL STUDY REPORT SYNOPSIS
Methodology:
This was a Phase 1, randomized, double-blind, vehicle-controlled, parallel cohort study toevaluate the safety, tolerability, skin irritation potential, and PK of PF-07038124 in Japanese
healthy adult participants. This study consisted of 2 cohorts to evaluate 2 administration areasin parallel: PF-07038124 at 0.01% concentration and vehicle to 2000 cm2 of skin (Cohort 1;approximately 10% body surface area [BSA]) or 4000 cm2 of skin (Cohort 2; approximately
20% BSA).
Participants were randomized to receive PF-07038124 or vehicle in a ratio of 4:2(4 PF-07038124: 2 vehicle) per cohort. Each participant received multiple doses ofPF-07038124 or vehicle, starting on Day 1 topically applied for 10 consecutive days; applied
once daily (QD) in the AM for Cohort 1 and Cohort 2.
The total participation time for each participant was approximately 66 days, including thescreening period of up to 28 days, the double-blind treatment period of 10 days, and thefollow-up period of 28 days from last dose of the study intervention.
Number of Participants (Planned and Analyzed):
Approximately 12 Japanese healthy adult participants were planned to participate in thisstudy. Overall, 12 participants were enrolled and randomly assigned to the treatment andwere included in the safety analysis set. The 8 participants of PF-07038124 treatment groupwere included in the PK analysis set.
Diagnosis and Main Criteria for Inclusion and Exclusion:
Enrolled in this study were male and female healthy participants who were 20 to 55 years ofage, inclusive, with body mass index (BMI) of 17.5 to 25 kg/m2 and a total body weight50 kg (110 lb); participants had 4 biologically Japanese grandparents who were born inJapan; participants who were willing and able to comply with all scheduled visits, treatment
plan, laboratory tests, lifestyle considerations, and other study procedures.
Participants were excluded if they had any visible skin damage or skin condition(eg, sunburn, excessively deep tans, uneven skin tones, tattoos, scars, excessive hair,numerous freckles, or other disfigurations); had a history of or had active forms ofdermatitides/eczematous conditions or other inflammatory skin diseases that would interferewith evaluation of the test site reaction; had undergone significant trauma or major surgery
within 4 weeks of screening.
Study Interventions, Dose, Mode of Administration, and Batch Number(s):The study intervention was applied in blinded fashion, at the clinical research unit. Allapplications of the study intervention were dispensed and applied by study site staff fromDay 1 through Day 10. Every effort was made for the dose applications on Day 2 to Day 10
to be completed at 24 ± 2 hour intervals from the recorded time of completion of the Day 1
dose application, for each participant (Table S2).
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CLINICAL STUDY REPORT SYNOPSIS
The application area included a treatment area of 2000 cm2±200 cm2 (approximately 10%BSA) for Cohort 1. For Cohort 2, the treatment area was 4000 cm2±400 cm2 (approximately
20% BSA). The application area included the back as well as other extremities, abdomen
and/or chest, identified by the investigator.
Table S2. Study Interventions Administered
Investigational
ProductDescription
PF-07038124
0.1 mg/g TopicalOintment in 60 gTube
Placebo for
PF-07038124
Topical Ointment
in 60 g Tube

Vendor Lot
Number

Pfizer Lot
NumberStrength/Potency

Dosage Form

K200721A

20-003576

0.1 mg/g

Ointment

K200714A

20-003423

0 mg/gOintment

CCI
Duration of Study Intervention:
The study intervention was applied QD for 10 consecutive days from Day 1 AM throughDay 10 AM.
Summary of Results:
Demographic and Other Baseline Characteristics:
All enrolled participants were male, Asian (Japanese), and between 33 to 53 years old. The
total mean (standard deviation [SD]) age was 41.6 (7.46) years. Across all treatment groups,
body weight ranged from 52.5 to 74.6 kg and BMI ranged from 17.6 to 24.4 kg/m2.
Exposure:
All participants completed treatment for 10 days in Cohorts 1 and 2.
Safety Results:
In total, 1 all-causality mild treatment-emergent adverse event (TEAE) was reported and was
not considered to be treatment-related by the investigator. One participant in PF-07038124
4000 cm2 treatment group experienced a TEAE of alanine aminotransferase increased of mild
severity (Table S3).

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Protocol C3941003

CLINICAL STUDY REPORT SYNOPSIS

Table S3. Treatment-Emergent Adverse Events (All Causalities) - Safety Analysis
Set (Protocol C3941003)
PFVehicle
PFVehicle Pooled07038124
200007038124
4000 Vehicle
2000 cm2cm24000 cm2cm2
Number (%) of Participants

Totaln (%)

n (%)

n (%)

n (%)

n (%)

n (%)

Participants evaluable for adverse events

4242412

Number of adverse events

001001

Participants with adverse events

001 (25.0)001 (8.3)

Participants with serious adverse events

000000Participants with severe adverse events

000000Participants discontinued from study due to adverseeventsa

000000Participants discontinued study drug due to AE andcontinue Studyb

000000Participants with dose reduced or temporary
discontinuation due to adverse events

000000Includes data up to 365 days after last dose of study drug.
Except for the Number of Adverse Events participants are counted only once per treatment in each row.
Serious Adverse Events - according to the investigator's assessment.
a. Participants who have an AE record that indicates that the AE caused the participant to be discontinued from the study.
b. Participants who have an AE record that indicates that Action Taken with Study Treatment was Drug Withdrawn butAEdid not Cause the Participant to be discontinued from Study.
MedDRA v24.0 coding dictionary applied.
PFIZER CONFIDENTIAL SDTM Creation: 12OCT2021 (13:45) Source Data: adae Table Generation: 15OCT2021(18:14)(Database snapshot date : 08OCT2021) Output File: ./csr6/C3941003/adae_s010
Table 14.3.1.2.1 PF-07038124 is for Pfizer internal use.

In general, all participants were rated with Score 0 using Draize scoring and did not have anyvisible skin reaction.
There were no deaths, serious adverse events (AEs), severe AEs, permanent discontinuations,
temporary discontinuations or dose reductions due to AEs reported in this study. None of thelaboratory abnormalities were reported as an AE or considered clinically significant. Nochange from baseline in electrocardiogram and vital signs were considered clinicallysignificant and none were reported as an AE.

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CLINICAL STUDY REPORT SYNOPSIS
Pharmacokinetic Results:
The PK of PF-07038124 were assessed on Day 1, Day 4, Day 7, and Day 10. Allconcentrations on Day 1, Day 4, and Day 7 were below the limit of quantification (BLQ) for
both treatments. The majority of concentrations on Day 10 were BLQ: up to 24 hours
postdose, 93% and 65% of plasma PK samples of PF-07038124 were BLQ of 10 pg/mL for
PF-07038124 2000 cm2 treatment and PF-07038124 4000 cm2 treatment, respectively. Basedon high percentage of BLQ values were observed, a limited number of participants had valid
parameter values.
The geometric mean (minimum, maximum) in area under the plasma concentration-time
profile from time 0 to time tau, the dosing interval, where tau = 24 hours (AUCtau) on Day 10for PF-07038124 4000 cm2 treatment was 0.1650 pg•hr/mL (0.000, 287 pg•hr/mL). The
geometric mean (minimum, maximum) in maximum plasma concentration (Cmax) on Day 10for PF-07038124 2000 cm2 treatment and PF-07038124 4000 cm2 treatment was0.001965 pg/mL (0.000, 14.9 pg/mL) and 0.03911 pg/mL (0.000, 17.6 pg/mL), respectively.
It’s hard to assess the dose-proportionality because the valid parameter values were limited;
however, number of concentrations that were above the upper limit of quantitation ofPF-07038124 4000 cm2 treatment was higher than that of PF-07038124 2000 cm2 treatment.
Inter-participant variability for PF-07038124 exposure based on geometric percent
coefficient of variation were large because the majority of concentrations were BLQ.
Pharmacodynamic Results: (Not Applicable)
Other Results: (Not Applicable)
Conclusions:
Safety:All PF-07038124 topical doses (0.01% QD in 2000 cm2 of skin area and 0.01% QD in
4000 cm2 of skin area) were generally safe and well-tolerated both locally and systemicallyin Japanese healthy participants evaluated in this study.
PK:
Following multiple topical administration of PF-07038124 in Japanese healthy participants,
all concentrations were BLQ on Day 1, Day 4, and Day 7. The majority of concentrations
were BLQ on Day 10: up to 24 hours postdose, 93% and 65% of plasma PK samples ofPF-07038124 were BLQ of 10 pg/mL for PF-07038124 2000 cm2 treatment andPF-07038124 4000 cm2 treatment, respectively.

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