A Study to Learn About mRNA Vaccines Against Influenza in Adults

NCT07431853 · tracked via the Priya Life Science USA tracker

Sponsor

Pfizer

Phase

Phase 2

Started

2026-02-23

Last updated

2026-05-06

Condition(s) studied

Healthy Adults

Investigational drug(s) / intervention(s)

Vaccine Candidate #1Vaccine Candidate #2Vaccine Candidate #3Vaccine Candidate #4Vaccine Candidate #5Vaccine Candidate #6TIV1 or TIV2

Vaccine Candidate #1: Investigational influenza Vaccine

Vaccine Candidate #2: Investigational influenza Vaccine

Vaccine Candidate #3: Investigational Influenza Vaccine

Vaccine Candidate #4: Investigational Influenza Vaccine

Vaccine Candidate #5: Investigational Influenza Vaccine

Vaccine Candidate #6: Investigational Influenza Vaccine

TIV1 or TIV2: Licensed influenza vaccine

Study summary

The purpose of this study is to learn about safety in participants taking the study vaccine (mRNA-based vaccine) and the ability of the study vaccine to trigger the body's immune response, targeting the flu virus (influenza virus).

This study is seeking healthy participants 18 years of age or older. All participants in this study will receive only 1 dose in their arm, to deliver one of the experimental flu vaccines or one of the approved flu vaccines used for comparison.

Participants will take part in this study for about 6 months, and participants will need to visit the study site at least 3 times. A blood sample will be taken at each of the 3 planned study visits and a swab from inside the nose will be taken at the first study visit.

Eligibility

Sex

ALL

Min age

18 Years

Max age

—

Healthy volunteers

Accepted

Inclusion Criteria • Healthy and medically stable participants who are determined by medical history, physical examination (if clinically required), and clinical judgment of the investigator to be eligible for inclusion in the study. Exclusion Criteria * Tested positive for influenza ≤5 months (150 days) prior to Visit 1 (Day 1). * Vaccination with any investigational or licensed influenza vaccine ≤5 months (150 days) before Visit 1 (Day 1). * Receipt of antiviral therapies for influenza (eg, Tamiflu) ≤5 months (150 days) prior to Visit 1 (Day 1).

Primary outcome measure(s)

Percentage of participants reporting prespecified local reactions following vaccination — Within 7 days after vaccination
Percentage of participants reporting prespecified systemic events following vaccination. — Within 7 days after vaccination
Percentage of participants reporting adverse events (AEs) following vaccination. — Within 1 month after vaccination
Percentage of participants reporting serious adverse events (SAEs) following vaccination. — Within 6 months after vaccination
Percentage of participants reporting newly diagnosed chronic medical conditions (NDCMCs) following vaccination. — Within 6 months after vaccination

Trial sites (15)

Facility	City	Region	Status
AMR Clinical	Mobile	Alabama	Recruiting
Diablo Clinical Research, LLC d/b/a Flourish Research	Walnut Creek	California	Recruiting
Clinical Research Consulting, LLC	Milford	Connecticut	Recruiting
George Washington Medical Faculty Associates	Washington D.C.	District of Columbia	Recruiting
Indago Research & Health Center, Inc	Hialeah	Florida	Recruiting
Palm Springs Community Health Center	Miami Lakes	Florida	Recruiting
Clinical Research Atlanta	Stockbridge	Georgia	Recruiting
East-West Medical Research Institute	Honolulu	Hawaii	Recruiting
AMR Clinical	Kansas City	Missouri	Recruiting
Rochester Clinical Research, LLC	Rochester	New York	Recruiting
DM Clinical Research - Philadelphia	Philadelphia	Pennsylvania	Recruiting
SMS Clinical Research LLC	Mesquite	Texas	Recruiting
DM Clinical Research	Tomball	Texas	Recruiting
J. Lewis Research, Inc. / Foothill Family Clinic	Salt Lake City	Utah	Recruiting
Charlottesville Medical Research Center, LLC	Charlottesville	Virginia	Recruiting

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Official registry record

This page summarises publicly available registry data for informational purposes — not medical advice. Eligibility is determined by each study team; patients should discuss participation with their clinician.

View NCT07431853 on ClinicalTrials.gov ↗ ← All trials in the USA