A Study of an Investigational Flu Seasonal/SARS-CoV-2 Combination Vaccine in Adults

NCT06680375 | Completed Phase 1 DMC FDA Drug

• 1 other identifier: 221542
• Study Type: interventional
• Target: 106
• Locations: 1 country
• Sites: 9

Brief Summary

This study will evaluate the reactogenicity, safety, and immune response of Flu Seasonal/SARS-CoV-2 mRNA (mRNA Flu/COVID-19) combination vaccine. The flu portion will target multiple strains of the flu virus, while the COVID-19 part will focus on the spike protein of the SARS-CoV-2 virus. Both parts of this vaccine have been tested individually before. This will be the first study to test the combined vaccine in humans in healthy adult participants.

Conditions

COVID-19

Keywords

Combination vaccine; Flu Seasonal; SARS-CoV-2 mRNA; Healthy younger adults; Healthy older adults; Safety; Reactogenicity; Immunogenicity; First time in humans

Outcome Measures

Primary Outcomes (10)

• Percentage of participants with increase in grading for at least one laboratory value from administration of study intervention

  Food and Drug Administration (FDA) toxicity grading scales for biochemistry hematology parameters are evaluated. Grades are defined as follows: Grade 1 - Mild; Grade 2 - Moderate; Grade 3 - Severe; Grade 4 -Potentially life threatening.

  From Day 1 to Day 8

• Percentage of participants with solicited administration site adverse events (AEs)

  The AEs considered are pain, redness, swelling and lymphadenopathy.

  From Day 1 to Day 7

• Percentage of participants with solicited systemic AEs

  The 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

• Percentage 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

• Percentage 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 183 (study end)

• Percentage of participants with serious adverse events (SAEs)

  A 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 183 (study end)

• Percentage of participants with adverse events of special interest (AESIs)

  The following events are considered as AESI in this study: severe hypersensitivity reactions within 24 hours after study intervention administration, myocarditis/pericarditis and potential immune-mediated diseases (pIMDs).

  From Day 1 to Day 183 (study end)

• Geometric mean titer (GMT) ratio of antigen 1 antibody for investigational mRNA Flu/COVID-19 (pooled dose 1 and dose 2) and mRNA flu vaccines

  At Day 29

• GMT ratio of antigen 2 antibody for investigational mRNA Flu/COVID-19 (pooled dose 1 and dose 2) and mRNA flu seasonal vaccines

  At Day 29

• GMT ratio of serum neutralization titers against pseudovirus bearing spike from SARS-CoV-2 vaccine matched variant(s) for investigational mRNA Flu/COVID-19 (pooled dose 1 and dose 2) and mRNA COVID-19 vaccines

  At Day 29

Secondary Outcomes (13)

• GMT ratio of antigen 1 antibody for the investigational mRNA Flu/COVID-19 vaccines (dose 1 and 2) and Flu vaccines (pooled group) and licensed Flu vaccine co-administered with a licensed mRNA COVID-19 vaccine

  At Day 29

• GMT ratio of antigen 2 antibody for the investigational mRNA Flu/COVID-19 vaccines (dose 1 and 2) and Flu vaccines (pooled group) and licensed Flu vaccine co-administered with a licensed mRNA COVID-19 vaccine

  At Day 29

• GMT ratio of serum neutralization titers against pseudovirus bearing spike from SARS-CoV-2 vaccine matched variant(s)

  At Day 29

• GMTs of antigen 1 antibody for the investigational mRNA Flu/COVID-19 vaccines, mRNA Flu Seasonal vaccine and the licensed Flu Seasonal vaccine co-administered with a licensed mRNA COVID-19 vaccine

  At Day 92 and Day 183 (Study end)

• Geometric mean increase (GMI) in antigen 1 antibody for the investigational mRNA Flu/COVID-19 vaccines, mRNA Flu Seasonal vaccine and the licensed Flu Seasonal vaccine co-administered with a licensed mRNA COVID-19 vaccine

  From Day 1 to Day 29, from Day 1 to Day 92 and from Day 1 to Day 183 (study end)

Study Arms (6)

mRNA Flu/COVID-19 Dose 1 Group

EXPERIMENTAL

Participants receive one dose of investigational Flu mRNA vaccine composition in combination with a Dose 1 of a COVID-19 component and 1 dose of placebo on Day 1.

Combination Product: Flu Seasonal /SARS-CoV-2 mRNA Dose 1; Drug: Placebo

mRNA Flu/COVID-19 Dose 2 Group

EXPERIMENTAL

Participants receive one dose of a Flu mRNA vaccine composition in combination with a Dose 2 of a COVID-19 component and 1 dose of placebo on Day 1.

Combination Product: Flu Seasonal /SARS-CoV-2 mRNA Dose 2; Drug: Placebo

Flu+COVID-19 Group

ACTIVE COMPARATOR

Participants receive one dose of a licensed Flu Seasonal vaccine and a licensed mRNA COVID-19 vaccine on Day 1.

Combination Product: Licensed Flu Seasonal; Combination Product: Licensed COVID-19 mRNA

mRNA Flu Group

ACTIVE COMPARATOR

Participants receive one dose of an investigational mRNA Flu Seasonal vaccine and 1 dose of placebo on Day 1.

Combination Product: Flu Seasonal mRNA; Drug: Placebo

mRNA COVID-19 Dose 1 Group

ACTIVE COMPARATOR

Participants receive one dose of Dose 1 investigational mRNA COVID-19 vaccine and 1 dose of placebo on Day 1.

Combination Product: SARS-CoV-2 mRNA Dose 1; Drug: Placebo

mRNA COVID-19 Dose 2 Group

ACTIVE COMPARATOR

Participants receive one Dose 2 investigational mRNA COVID-19 vaccine and 1 dose of placebo on Day 1.

Combination Product: SARS-CoV-2 mRNA Dose 2; Drug: Placebo

Interventions

Flu Seasonal /SARS-CoV-2 mRNA Dose 1 COMBINATION_PRODUCT

A Flu mRNA vaccine composition in combination with Dose 1 of a COVID-19 component will be administered.

mRNA Flu/COVID-19 Dose 1 Group

Flu Seasonal /SARS-CoV-2 mRNA Dose 2 COMBINATION_PRODUCT

A Flu mRNA vaccine composition in combination with Dose 2 of a COVID-19 component will be administered.

mRNA Flu/COVID-19 Dose 2 Group

Flu Seasonal mRNA COMBINATION_PRODUCT

An investigational mRNA Flu Seasonal vaccine will be administered.

mRNA Flu Group

SARS-CoV-2 mRNA Dose 1 COMBINATION_PRODUCT

Dose 1 of an investigational mRNA COVID-19 vaccine will be administered.

mRNA COVID-19 Dose 1 Group

SARS-CoV-2 mRNA Dose 2 COMBINATION_PRODUCT

Dose 2 of an investigational mRNA COVID-19 vaccine will be administered.

mRNA COVID-19 Dose 2 Group

Licensed Flu Seasonal COMBINATION_PRODUCT

A licensed Flu Seasonal vaccine will be administered.

Flu+COVID-19 Group

Licensed COVID-19 mRNA COMBINATION_PRODUCT

A licensed mRNA COVID-19 vaccine will be administered.

Flu+COVID-19 Group

Placebo DRUG

A placebo will be administered.

mRNA COVID-19 Dose 1 Group; mRNA COVID-19 Dose 2 Group; mRNA Flu Group; mRNA Flu/COVID-19 Dose 1 Group; mRNA Flu/COVID-19 Dose 2 Group

Eligibility Criteria

• Age: 18 Years - 64 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

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, return for follow-up visits).
• Written informed consent obtained from the participant prior to performance of any study-specific procedure.
• A male or female 18-64 years of age (YA: 18-64) at the time of the study intervention administration.
• Participants must have a body mass index (BMI) \>=18 kg/m² and less than equal to (\<=) 40 kg/m2.
• Healthy participants or medically stable patients as established by medical history, clinical examination and (safety laboratory assessments). Participants with chronic medical conditions with or without specific treatment (e.g., chronic metabolic, cardiac, pulmonary, renal, hepatic, 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 enrolment.
• Prior receipt of a COVID-19 vaccine. This may be from a completed primary vaccination series or booster dose(s) of an approved or authorized COVID-19 vaccine. The last COVID-19 vaccination must have been received at least 90 days prior to randomization.
• Women of non-childbearing potential may be enrolled in the study.
• Women of childbearing potential may be enrolled in the study if the participant:
• has practiced adequate contraception for 4 weeks prior to study intervention administration, and
• has a negative pregnancy test on the day of study intervention administration, and has agreed to continue adequate contraception for at least 8 weeks after completion of the study intervention administration.

You may not qualify if:

• Medical conditions
• Any clinically significant hematological, biochemical laboratory abnormality.
• Participant tested positive for influenza by local health authority-approved testing methods within 180 days prior to Day 1.
• A documented history of confirmed SARS-CoV-2 infection within 90 days before study vaccination.
• Has had known close contact with anyone who had confirmed influenza or a confirmed SARS-CoV-2 infection within 2 weeks before study vaccination.
• Current or past malignancy, unless completely resolved without clinically significant sequelae (e.g., no evidence of disease following successful treatment of basal cell carcinoma cases are allowed) for \>5 years.
• Has any medical disease or psychiatric condition that, in the opinion of the investigator, precludes study participation because it would place the participant at an unacceptable risk of injury, would render them unable to meet the requirements of the protocol, or may interfere with successful completion of the study.
• Has a bleeding disorder (e.g., factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required).
• Any history of an immunosuppressive or immunodeficient condition resulting from disease (e.g., HIV infection or congenital immunodeficiency).
• Has a history of hypersensitivity or severe allergic reaction including anaphylaxis, generalized urticaria, angioedema, and other significant reactions to any previous mRNA or non-mRNA vaccine or any component of the study intervention(s) (including polyethylene glycol, egg proteins and aminoglycoside antibiotics)
• History of uncontrolled neurological disorders or seizures, including Guillain-Barré syndrome (within 6 weeks of receiving any vaccine) and Bell's Palsy, with the exception of febrile seizures during childhood.
• History of or current suspicion of myocarditis or pericarditis (including following administration of an mRNA vaccine); or idiopathic cardiomyopathy, or presence of any medical condition that increases the risk of myocarditis or pericarditis, including cocaine abuse, cardiomyopathy, endomyocardial fibrosis, hypereosinophilic syndrome, hypersensitivity myocarditis, eosinophilic granulomatosis with polyangiitis and persistent myocardial infection.
• Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study.
• Prior/Concomitant therapy

Sponsors & Collaborators

• GlaxoSmithKline: lead

Study Sites (9)

GSK Investigational Site

Anniston, Alabama, 36207, United States

Location

GSK Investigational Site

Rolling Hills Estates, California, 90274, United States

Location

GSK Investigational Site

Hialeah, Florida, 33012, United States

Location

GSK Investigational Site

Miami, Florida, 33147, United States

Location

GSK Investigational Site

Miami, Florida, 33186, United States

Location

GSK Investigational Site

Lenexa, Kansas, 66219, United States

Location

GSK Investigational Site

St Louis, Missouri, 63141, United States

Location

GSK Investigational Site

Omaha, Nebraska, 68134, United States

Location

GSK Investigational Site

Rochester, New York, 14609, United States

Location

MeSH Terms

Conditions

COVID-19

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, 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: November 6, 2024
• First Posted: November 8, 2024
• Study Start: November 11, 2024
• Primary Completion: June 9, 2025
• Study Completion: June 9, 2025
• Last Updated: September 11, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• 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.

Locations

US (9)