NCT06436703

Brief Summary

The purpose of this study is to learn if modified RNA (modRNA) vaccines for the prevention of influenza are:

  • safe; and
  • how these vaccines produce an immune response in generally healthy adults. Immune response is the way the body protects itself against things it sees as harmful or foreign. RNA (also called ribonucleic acid) is one of two types of nucleic acid made by cells. RNA contains information that has been copied from DNA (the other type of nucleic acid). Cells make several different forms of RNA, and each form has a specific job in the cell. Many forms of RNA have functions related to making proteins. RNA is also the genetic material of some viruses instead of DNA. RNA can be made in the laboratory and used in research studies. Also called ribonucleic acid. Influenza is term used for flu illness. It is an infection caused by a virus that affects your mouth, nose, and throat. The study is seeking for participants who:
  • are at least 18 years of age
  • have not received an influenza vaccine within the last 6 months
  • are generally healthy This study will be divided into three sub-studies: Substudy A (SSA), Substudy B (SSB), and Substudy C (SSC). All participants, regardless of sub-study, will receive 1 dose of either of the following vaccines as an injection into their arm:
  • 1 of the modRNA influenza vaccines that is being studied; or
  • an approved influenza vaccine approved for use in their respective age group. Participants will be involved in this study for about 6 months. During this time, participants will have at least 3 clinic visits.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
1,202

participants targeted

Target at P75+ for phase_2

Timeline
Completed

Started May 2024

Shorter than P25 for phase_2

Geographic Reach
1 country

32 active sites

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

May 23, 2024

Completed
1 day until next milestone

First Submitted

Initial submission to the registry

May 24, 2024

Completed
7 days until next milestone

First Posted

Study publicly available on registry

May 31, 2024

Completed
8 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

February 5, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

February 5, 2025

Completed
Last Updated

January 9, 2026

Status Verified

January 1, 2026

Enrollment Period

9 months

First QC Date

May 24, 2024

Last Update Submit

January 7, 2026

Conditions

Outcome Measures

Primary Outcomes (18)

  • SSA - Percentage of Participants Reporting Local Reactions After Vaccination

    Pain at the injection site, redness, and swelling.

    From Day 1 Through at least Day 7 After Vaccination

  • SSA - Percentage of Participants Reporting Systemic Events After Vaccination

    Fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain.

    From Day 1 Through at least Day 7 After Vaccination

  • SSA - Percentage of Participants Reporting Adverse Events After Vaccination

    As elicited by investigational site staff

    From Day 1 Through 4 Weeks After Vaccination

  • SSA - Percentage of Participants Reporting Serious Adverse Events (SAE)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSA - Percentage of Participants Reporting Newly Diagnosed Chronic Medical Conditions (NDCMCs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSA - Percentage of Participants Reporting Medically Attended AEs (MAEs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSB - Percentage of Participants Reporting Local Reactions After Vaccination

    Pain at injection site, redness, and swelling.

    From Day 1 Through at least Day 7 After Vaccination

  • SSB - Percentage of Participants Reporting Systemic Events After Vaccination

    Fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain.

    From Day 1 Through at least Day 7 After Vaccination

  • SSB - Percentage of Participants Reporting Adverse Events After Vaccination

    As elicited by investigational site staff

    From Day 1 Through 4 Weeks After Vaccination

  • SSB - Percentage of Participants Reporting Serious Adverse Events (SAE)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSB - Percentage of Participants Reporting Newly Diagnosed Chronic Medical Conditions (NDCMCs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSB - Percentage of Participants Reporting Medically Attended AEs (MAEs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSC - Percentage of Participants Reporting Local Reactions After Vaccination

    Pain at the injection site, redness, and swelling.

    From Day 1 Through at least Day 7 After Vaccination

  • SSC - Percentage of Participants Reporting Systemic Events After Vaccination

    Fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain.

    From Day 1 Through at least Day 7 After Vaccination

  • SSC - Percentage of Participants Reporting Adverse Events After Vaccination

    As elicited by investigational site staff

    From Day 1 Through 4 Weeks After Vaccination

  • SSC - Percentage of Participants Reporting Serious Adverse Events (SAE)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSC - Percentage of Participants Reporting Newly Diagnosed Chronic Medical Conditions (NDCMCs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

  • SSC - Percentage of Participants Reporting Medically Attended AEs (MAEs)

    As elicited by investigational site staff

    From Day 1 Through 6 Months After Vaccination

Secondary Outcomes (8)

  • SSA - HAI Geometric Mean Titers (GMTs) for each strain

    4 Weeks After Vaccination

  • SSA - HAI geometric mean fold rise (GMFR) for each strain

    4 Weeks After Vaccination

  • SSA - The proportion of participants achieving HAI seroconversion for each strain

    4 Weeks After Vaccination

  • SSA - The proportion of participants with HAI titers ≥1:40 for each strain

    Baseline and 4 Weeks After Vaccination

  • SSB - HAI geometric mean titers (GMTs) for each strain

    4 Weeks After Vaccination

  • +3 more secondary outcomes

Study Arms (19)

SSA: Influenza ModRNA Vaccine 2A

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSA: Influenza ModRNA Vaccine 3A

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSA: Influenza ModRNA Vaccine 4A

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSA: Influenza ModRNA Vaccine 5A

EXPERIMENTAL

\- Single dose on Day 1

Biological: Influenza ModRNA Vaccine

SSA: QIV1

ACTIVE COMPARATOR

\- Single dose on Day 1

Biological: Quadrivalent Influenza Vaccine (QIV)

SSB: Influenza ModRNA Vaccine 3B

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSB: Influenza ModRNA Vaccine 4B

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSB: Influenza ModRNA Vaccine 5B

EXPERIMENTAL

\- Single dose on Day 1

Biological: Influenza ModRNA Vaccine

SSB: QIV2

ACTIVE COMPARATOR

\- Single Dose on Day 1

Biological: Quadrivalent Influenza Vaccine (QIV)

SSB: QIV3

ACTIVE COMPARATOR

\- Single Dose on Day 1

Biological: Quadrivalent Influenza Vaccine (QIV)

SSC: Influenza ModRNA Vaccine 3C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 4C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 5C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 6C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 7C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 8C

EXPERIMENTAL

\- Single Dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: Influenza ModRNA Vaccine 9C

EXPERIMENTAL

\- Single dose on Day 1

Biological: Influenza ModRNA Vaccine

SSC: QIV2

ACTIVE COMPARATOR

\- Single Dose on Day 1

Biological: Quadrivalent Influenza Vaccine (QIV)

SSC: QIV3

ACTIVE COMPARATOR

\- Single Dose on Day 1

Biological: Quadrivalent Influenza Vaccine (QIV)

Interventions

Intramuscular injection

SSA: Influenza ModRNA Vaccine 2ASSA: Influenza ModRNA Vaccine 3ASSA: Influenza ModRNA Vaccine 4ASSA: Influenza ModRNA Vaccine 5ASSB: Influenza ModRNA Vaccine 3BSSB: Influenza ModRNA Vaccine 4BSSB: Influenza ModRNA Vaccine 5BSSC: Influenza ModRNA Vaccine 3CSSC: Influenza ModRNA Vaccine 4CSSC: Influenza ModRNA Vaccine 5CSSC: Influenza ModRNA Vaccine 6CSSC: Influenza ModRNA Vaccine 7CSSC: Influenza ModRNA Vaccine 8CSSC: Influenza ModRNA Vaccine 9C

Intramuscular injection

SSA: QIV1SSB: QIV2SSB: QIV3SSC: QIV2SSC: QIV3

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Applies to all 3 substudies:
  • participants ≥18 years of age.
  • generally healthy participants.
  • Substudy C ONLY:
  • \- receipt of licensed influenza vaccination for the 2023-2024 flu season at least 6 months ago.

You may not qualify if:

  • All 3 substudies:
  • diagnosis of influenza (by clinical testing) in the last 6 months.
  • immunocompromised individuals with known or suspected immunodeficiency
  • receipt of any investigational or licensed influenza vaccines within 6 months.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (32)

Alliance for Multispecialty Research, LLC

Mobile, Alabama, 36608, United States

Location

Headlands Research - Scottsdale

Scottsdale, Arizona, 85260, United States

Location

Anaheim Clinical Trials, LLC

Anaheim, California, 92801, United States

Location

Orange County Research Center

Lake Forest, California, 92630, United States

Location

Artemis Institute for Clinical Research

San Diego, California, 92103, United States

Location

Diablo Clinical Research, Inc.

Walnut Creek, California, 94598, United States

Location

Clinical Research Consulting

Milford, Connecticut, 06460, United States

Location

Indago Research & Health Center, Inc

Hialeah, Florida, 33012, United States

Location

Research Centers of America ( Hollywood )

Hollywood, Florida, 33024, United States

Location

Research Centers of America

Hollywood, Florida, 33024, United States

Location

Palm Springs Community Health Center

Miami Lakes, Florida, 33014, United States

Location

Clinical Neuroscience Solutions, Inc.

Orlando, Florida, 32801, United States

Location

Headlands Research Orlando

Orlando, Florida, 32819, United States

Location

Qps-Mra, Llc

South Miami, Florida, 33143, United States

Location

East-West Medical Research Institute

Honolulu, Hawaii, 96814, United States

Location

Alliance for Multispecialty Research, LLC

New Orleans, Louisiana, 70119, United States

Location

Prism Research LLC dba Nucleus Network

Saint Paul, Minnesota, 55114, United States

Location

Clinical Research Professionals

Chesterfield, Missouri, 63005, United States

Location

Alliance for Multispecialty Research, LLC

Kansas City, Missouri, 64114, United States

Location

Rochester Clinical Research, LLC

Rochester, New York, 14609, United States

Location

Duke Vaccine and Trials Unit

Durham, North Carolina, 27703, United States

Location

M3 Wake Research, Inc.

Raleigh, North Carolina, 27612, United States

Location

DM Clinical Research - Philadelphia

Philadelphia, Pennsylvania, 19107, United States

Location

Headlands Horizons LLC

Brownsville, Texas, 78526, United States

Location

SMS Clinical Research

Mesquite, Texas, 75149, United States

Location

Clinical Trials of Texas, LLC dba Flourish Research

San Antonio, Texas, 78229, United States

Location

Clinical Trials of Texas, LLC

San Antonio, Texas, 78229, United States

Location

Dynamed Clinical Research, LP d/b/a DM Clinical Research

Tomball, Texas, 77375, United States

Location

J. Lewis Research, Inc. / Foothill Family Clinic

Salt Lake City, Utah, 84109, United States

Location

J. Lewis Research, Inc. / Foothill Family Clinic South

Salt Lake City, Utah, 84121, United States

Location

Charlottesville Medical Research

Charlottesville, Virginia, 22911, United States

Location

Alliance for Multispecialty Research, LLC

Norfolk, Virginia, 23502, United States

Location

Related Links

MeSH Terms

Conditions

Influenza, Human

Interventions

Influenza Vaccines

Condition Hierarchy (Ancestors)

Respiratory Tract InfectionsInfectionsOrthomyxoviridae InfectionsRNA Virus InfectionsVirus DiseasesRespiratory Tract Diseases

Intervention Hierarchy (Ancestors)

Viral VaccinesVaccinesBiological ProductsComplex Mixtures

Study Officials

  • Pfizer CT.gov Call Center

    Pfizer

    STUDY DIRECTOR

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Masking Details
This study will be an observer-blinded and Sponsor-unblinded study.
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 24, 2024

First Posted

May 31, 2024

Study Start

May 23, 2024

Primary Completion

February 5, 2025

Study Completion

February 5, 2025

Last Updated

January 9, 2026

Record last verified: 2026-01

Data Sharing

IPD Sharing
Will share

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.

More information

Locations