NCT07121192

Brief Summary

"The purpose of this study is to assess the reactogenicity, safety and immune response of GlaxoSmithKlines (GSK) messenger RNA (mRNA)-based multivalent seasonal influenza vaccine candidates administered in healthy younger and older adults."

Trial Health

75
On Track

Trial Health Score

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

Enrollment
776

participants targeted

Target at P75+ for phase_2

Timeline
0mo left

Started Aug 2025

Shorter than P25 for phase_2

Geographic Reach
1 country

22 active sites

Status
active not recruiting

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 Progress97%
Aug 2025May 2026

First Submitted

Initial submission to the registry

August 6, 2025

Completed
7 days until next milestone

First Posted

Study publicly available on registry

August 13, 2025

Completed
12 days until next milestone

Study Start

First participant enrolled

August 25, 2025

Completed
9 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 15, 2026

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

May 15, 2026

Last Updated

November 14, 2025

Status Verified

November 1, 2025

Enrollment Period

9 months

First QC Date

August 6, 2025

Last Update Submit

November 12, 2025

Conditions

Keywords

InfluenzaHumanVirus DiseasesInfectionsmRNA vaccineYounger AdultsOlder Adultsmultivalent seasonal influenza vaccine

Outcome Measures

Primary Outcomes (11)

  • Geometric Mean Titer (GMT) Ratio of Antigen 1 Titer

    At Day 29

  • Geometric Mean Increase (GMI) of Antigen 1 Titer

    From Day 1 to Day 29

  • Percentage of Participants with Antigen 1 Seroconversion Rate (SCR)

    From Day 1 to Day 29

  • Percentage of Participants with Antigen 1 Seroprotection Rate (SPR)

    At Day 1 and Day 29

  • Number of Participants with Solicited Administration Site Adverse Events (Aes)

    The solicited administration site AEs considered are pain, redness, swelling and lymphadenopathy.

    From Day 1 to Day 7

  • Number of Participants with Solicited Systemic Aes

    The solicited systemic AEs considered are fever, headache, fatigue, myalgia, arthralgia and chills. Fever is defined as temperature greater than or equal to (\>=) 38 °C/100.4°F regardless the location of measurement.

    From Day 1 to Day 7

  • Number of Participants with Unsolicited Aes

    An unsolicited AE is an AE that was either not included in the list of solicited events or could be included in the list of solicited events but with an onset outside the specified period of follow-up for solicited events.

    From Day 1 to Day 28

  • Number of Participants with Serious Adverse Events (SAEs)

    SAE is an AE which results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or other situations that are considered serious per medical or scientific judgment.

    From Day 1 to Day 181 (study end)

  • Number of Participants with Adverse Events of Special Interest (AESIs)

    From Day 1 to Day 181 (study end)

  • Number of Participants with Medically Attended Adverse Events (MAAEs)

    A MAAE is an AE for which the participant received medical attention including any symptom or illness requiring hospitalization, or an emergency room visit, or visit to/by a healthcare professional.

    From Day 1 to Day 181 (study end)

  • Number of Participants with any Laboratory abnormalities

    Click here to enter text.

    From Day 1 to Day 29

Secondary Outcomes (3)

  • GMT Ratio of Antigen 2 Titer

    At Day 29

  • GMI of Antigen 2 Titer

    From Day 1 to Day 29

  • Percentage of Participants with Antigen 2 SCR

    From Day 1 to Day 29

Study Arms (9)

Flu mRNA_1_YA

EXPERIMENTAL

Eligible Younger Adults (YA) participants receive a single dose of Flu mRNA Formulation A (GSK6479720A) as study intervention at Day 1.

Biological: Flu mRNA (Formulation A)

Flu mRNA_2_YA

EXPERIMENTAL

Eligible YA participants receive a single dose of Flu mRNA Formulation B (GSK6479715A) as study intervention at Day 1.

Biological: Flu mRNA (Formulation B)

Comparator_1_YA

ACTIVE COMPARATOR

Eligible YA participants receive a single dose of comparator 1 at Day 1.

Combination Product: Comparator 1

Comparator_2_YA

ACTIVE COMPARATOR

Eligible YA participants receive a single dose of comparator 2 at Day 1.

Combination Product: Comparator 2

Flu mRNA_1_OA

EXPERIMENTAL

Eligible Older Adults (OA) participants receive a single dose of Flu mRNA Formulation A (GSK6479720A) as study intervention at Day 1.

Biological: Flu mRNA (Formulation A)

Flu mRNA_2_OA

EXPERIMENTAL

Eligible OA participants receive a single dose of Flu mRNA Formulation B (GSK6479715A) as study intervention at Day 1.

Biological: Flu mRNA (Formulation B)

Comparator_1_OA

EXPERIMENTAL

Eligible OA participants receive a single dose of comparator 1 at Day 1.

Combination Product: Comparator 1

Comparator_2_OA

ACTIVE COMPARATOR

Eligible OA participants receive a single dose of comparator 2 at Day 1.

Combination Product: Comparator 2

Comparator_3_OA

ACTIVE COMPARATOR

Eligible OA participants receive a single dose of comparator 3 at Day 1.

Combination Product: Comparator 3

Interventions

One dose of Flu mRNA (Formulation A) received intramuscularly.

Also known as: GSK6479720A
Flu mRNA_1_OAFlu mRNA_1_YA

One dose of Flu mRNA (Formulation B) received intramuscularly.

Also known as: GSK6479715A
Flu mRNA_2_OAFlu mRNA_2_YA
Comparator 1COMBINATION_PRODUCT

One dose of Comparator 1 received intramuscularly.

Comparator_1_OAComparator_1_YA
Comparator 2COMBINATION_PRODUCT

One dose of Comparator 2 received intramuscularly.

Also known as: Click here to enter text.
Comparator_2_OAComparator_2_YA
Comparator 3COMBINATION_PRODUCT

One dose of Comparator 3 received intramuscularly.

Comparator_3_OA

Eligibility Criteria

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

You may qualify if:

  • Participants, who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., completion of the eDiary, attendance to study contacts and study site visits, and ability to access and utilize a phone or other electronic communications) independently or with the assistance of a caregiver.
  • Written (physically, or digitally) informed consent obtained from the participant prior to performance of any study-specific procedure.
  • A male or female at least 18 YOA at the time of the screening.
  • Healthy participants or medically stable patients as established by medical history, and clinical examination. Participants with chronic medical conditions with or without specific treatment (e.g., chronic metabolic, cardiac, pulmonary, renal, neurologic, and hematologic diseases) are allowed to participate in this study, if considered by the investigator as medically stable. A stable medical condition is defined as disease not requiring significant change in therapy or hospitalization for worsening disease during 3 months before enrollment.
  • Female participants of non-childbearing potential may be enrolled in the clinical study.
  • Female participants of childbearing potential may be enrolled in the clinical study, if the participant:
  • Has practiced adequate contraception for at least 4 weeks prior to the study intervention administration, and
  • Has a negative urine pregnancy test within 24 hours prior to the study intervention administration, and
  • Has agreed to continue adequate contraception for at least 8 weeks after study intervention administration.
  • Body mass index (BMI) between18 kg/m\^² and 33kg/m\^².

You may not qualify if:

  • Immunosuppressive or immunodeficient conditions by history/exam; stable HIV-positive individuals on therapy can participate.
  • History of Guillain-Barré Syndrome within 6 weeks of receiving any vaccine.
  • Significant underlying illness that in the opinion of the investigator would be expected to prevent completion of the study (e.g., life-threatening disease likely to limit survival to less than 1 year).
  • Hypersensitivity to latex.
  • History of any reaction or hypersensitivity likely to be exacerbated by any component of the study intervention(s).
  • History of hypersensitivity or severe allergic reaction to any previous influenza vaccine.
  • History of hypersensitivity or severe allergic reaction to any previous mRNA vaccine.
  • History of or current suspicion of myocarditis or pericarditis, or medical issues increasing such risks.
  • Condition that in the judgment of the investigator would make intramuscular injection unsafe.
  • Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the clinical study.
  • History of confirmed influenza infection by local health authority-approved testing methods within 180 days prior to study intervention administration.
  • Use of any investigational or non-registered product (drug, vaccine or invasive medical device) other than the study intervention(s) during the period beginning 28 days before the dose of study intervention(s) (Day -28 to Day 1), or their planned use during the study period.
  • Administration of an influenza vaccine within 180 days before the study intervention administration or planned administration prior to Visit 4 (Day 29) during the study.
  • Administration of any non-live attenuated non-study vaccine in the period starting 14 days before the study intervention administration, or planned administration within 14 days after study intervention administration.
  • Administration of any live attenuated and/or mRNA non-study non-influenza vaccine in the period starting 28 days before the study intervention administration, or planned administration within 28 days after study intervention administration.
  • +8 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (22)

GSK Investigational Site

Anniston, Alabama, 36207, United States

Location

GSK Investigational Site

Fair Oaks, California, 95628, United States

Location

GSK Investigational Site

San Diego, California, 92120, United States

Location

GSK Investigational Site

San Diego, California, 92123, United States

Location

GSK Investigational Site

Walnut Creek, California, 94598, United States

Location

GSK Investigational Site

Hialeah, Florida, 33012, United States

Location

GSK Investigational Site

Jupiter, Florida, 33458, United States

Location

GSK Investigational Site

Miami, Florida, 33186, United States

Location

GSK Investigational Site

Atlanta, Georgia, 30281, United States

Location

GSK Investigational Site

Valparaiso, Indiana, 46383, United States

Location

GSK Investigational Site

Lenexa, Kansas, 66219, United States

Location

GSK Investigational Site

Springfield, Massachusetts, 01103, United States

Location

GSK Investigational Site

Carson City, Nevada, 89706, United States

Location

GSK Investigational Site

Rochester, New York, 14609, United States

Location

GSK Investigational Site

Greensboro, North Carolina, 27408, United States

Location

GSK Investigational Site

Cleveland, Ohio, 44122, United States

Location

GSK Investigational Site

North Charleston, South Carolina, 29405, United States

Location

GSK Investigational Site

Austin, Texas, 78705, United States

Location

GSK Investigational Site

DeSoto, Texas, 75115, United States

Location

GSK Investigational Site

Fort Worth, Texas, 76135, United States

Location

GSK Investigational Site

Newport News, Virginia, 23606, United States

Location

GSK Investigational Site

Seattle, Washington, 98104, United States

Location

MeSH Terms

Conditions

Influenza, HumanVirus DiseasesInfections

Condition Hierarchy (Ancestors)

Respiratory Tract InfectionsOrthomyxoviridae InfectionsRNA Virus InfectionsRespiratory Tract Diseases

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Masking Details
This is an Observer-blind study.
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 6, 2025

First Posted

August 13, 2025

Study Start

August 25, 2025

Primary Completion (Estimated)

May 15, 2026

Study Completion (Estimated)

May 15, 2026

Last Updated

November 14, 2025

Record last verified: 2025-11

Data Sharing

IPD Sharing
Will share

Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/About\_GSK\_Patient\_Level\_Data\_Sharing\_Final\_13July2023.pdf

Shared Documents
STUDY PROTOCOL, SAP, ICF, CSR
Time Frame
Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or asset(s) with development terminated across all indications.
Access Criteria
Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months, but an extension may be granted, when justified, for up to 6 months.
More information

Locations