A Study to Learn How Different Amounts of the Study Medicine Called PF-08065010 Are Tolerated and Act in the Body of Healthy Adults

AN INTERVENTIONAL, PHASE 1, RANDOMIZED STUDY WITH DOUBLE-BLIND AND SPONSOR-OPEN, PLACEBO-CONTROLLED SINGLE AND MULTIPLE DOSE ESCALATION TO EVALUATE THE SAFETY, TOLERABILITY, PHARMACOKINETICS, PHARMACODYNAMICS, AND IMMUNOGENICITY OF PF-08065010 IN HEALTHY ADULT PARTICIPANTS

The purpose of this study is to learn about the safety and effects of the study medicine (called PF-08065010) for possible treatment of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

This study is seeking participants who are:

• male or female between 18 and 65 years of age
• deemed to be healthy

Participants in this study will receive PF-08065010 or placebo. A placebo does not have any medicine in it but looks just like the medicine being studied. PF-08065010 or placebo will be given as a shot (in the abdomen, thigh or back of the arms) or as an IV infusion in the arm (given directly into a vein) at the study clinic.

In Part A, participants will take PF-08065010 or placebo only 1 time and will take part in this study for about 5 months. During this time, they will stay at the study clinic for about 9-10 days and will have about 6 more study visits at the study clinic.

Participants in Part B of the study will take PF-08065010 or placebo once a month, for 3 months and will take part in this study for about 7 months. During this time, they will stay at the study clinic for about 4 days each month and will have about 6 more study visits at the study clinic.

During study clinic stays and study visits, urine, blood samples, and physical exams will be done.

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy
• Intervention / Treatment: Drug: Placebo; Drug: PF-08065010

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Pfizer CT.gov Call Center; Phone Number: 1-800-718-1021; Email: ClinicalTrials.gov_Inquiries@pfizer.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• male or female between 18 and 65 years of age
• deemed to be healthy

Exclusion Criteria:

1. Evidence or history of clinically significant medical conditions.
2. History of human immunodeficiency virus (HIV) infection, hepatitis B, or hepatitis C; positive testing for HIV, hepatitis B surface antigen (HBsAg)or hepatitis C antibody (HCVAb).
3. History of alcohol abuse or binge drinking and/or any other illicit drug use or dependence within 6 months of Screening.
4. A positive urine drug test.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: Double

Number of Arms

14

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A: Cohort 1: single ascending dose (SAD); Dose A - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 2: single ascending dose (SAD); Dose B - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 3: single ascending dose (SAD); Dose C - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 4: single ascending dose (SAD); Dose D - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 5: single ascending dose (SAD); Dose E - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 6: single ascending dose (SAD); Dose F - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 7: single ascending dose (SAD); Dose G - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 8: single ascending dose (SAD); Optional Japanese Cohort dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 9: single ascending dose (SAD); Optional Chinese Cohort dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 10: single ascending dose (SAD); Optional Cohort with dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part A: Cohort 11: single ascending dose (SAD); Optional Cohort with dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part B: Cohort 12: multiple dose; Dose F - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part B: Cohort 13: multiple dose; Optional Cohort with dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).
Experimental: Part B: Cohort 14: multiple dose; Optional Cohort with dose to be determined - Participants will receive PF-08065010 or placebo.	Drug: Placebo; Placebo which will be SC or IV; Drug: PF-08065010; Experimental Pfizer compound which will be subcutaneous (SC) or intravenous (IV).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)	Part A	Baseline, approximately up to 5 months
Number of Participants With Clinically Significant Laboratory Abnormalities	Part A	Baseline, approximately up to 5 months
Number of Participants With Vital Sign Abnormalities	Part A	Baseline, approximately up to 5 months
Number of Participants with Change from Baseline in Physical Exam (PE) Parameters	Part A	Baseline, approximately up to 5 months
Number of Participants with Change from Baseline in Electrocardiogram (ECG) Parameters	Part A	Baseline, approximately up to 5 months
Number of Participants with Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)	Part B	Baseline, approximately up to 7 months
Number of Participants With Clinically Significant Laboratory Abnormalities	Part B	Baseline, approximately up to 7 months
Number of Participants with Vital Sign Abnormalities	Part B	Baseline, approximately up to 7 months
Number of Participants with Change from Baseline in Physical Exam (PE) Parameters	Part B	Baseline, approximately up to 7 months
Number of Participants with Change from Baseline in Electrocardiogram (ECG) Parameters	Part B	Baseline, approximately up to 7 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area Under the Plasma Concentration-time Profile from Time Zero to the Time of Last Quantifiable Concentration (AUClast)	Part A	Predose (Day 1), approximately up to 5 months
Area Under the Curve from Time Zero to Extrapolated Infinite Time (AUCinf)	Part A	Predose (Day 1), approximately up to 5 months
Maximum Observed Plasma Concentration (Cmax)	Part A	Predose (Day 1), approximately up to 5 months
Time to Reach Maximum Observed Plasma Concentration (Tmax)	Part A	Predose (Day 1), approximately up to 5 months
Plasma decay half-life (t1/2) is the time measured for the plasma concentration to decrease by one half.	Part A	Predose (Day 1), approximately up to 5 months
Area under the serum concentration time profile over the dosing interval of 28 days (AUCtau)	Part B	Predose (Day 1), approximately up to 7 months
Maximum Observed Plasma Concentration (Cmax)	Part B	Predose (Day 1), approximately up to 7 months
Time to Reach Maximum Observed Plasma Concentration (Tmax)	Part B	Predose (Day 1), approximately up to 7 months
Plasma Decay Half-Life (t1/2)	Part B	Predose (Day 1), approximately up to 7 months

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Estimated): April 13, 2026
• Primary Completion (Estimated): July 16, 2027
• Study Completion (Estimated): July 16, 2027

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: November 14, 2025
• First Posted (Actual): November 19, 2025

Study Record Updates

• Last Update Posted (Actual): March 19, 2026
• Last Update Submitted That Met QC Criteria: March 18, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: C6341001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No