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A Study on the Safety and Immune Response of Investigational mRNA Seasonal Flu/COVID-19 Combination Vaccine in Adults

A Phase 1, Observer-Blind, Randomized, Controlled Study to Evaluate the Safety and Immunogenicity of an Investigational mRNA Seasonal Flu/COVID-19 Combination Vaccine in Adults

Status
Recruiting
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07464314
Enrollment
225
Registered
2026-03-11
Start date
2026-03-09
Completion date
2027-06-03
Last updated
2026-06-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza, Human+COVID-19

Keywords

Influenza, COVID-19, SARS-CoV-2, mRNA vaccine, combination vaccine, immunogenicity, older adults

Brief summary

This early-stage study will look at a new mRNA vaccine that combines defenses against both seasonal flu and COVID-19 in terms of its safety and how it builds protection. Healthy adults aged 65 to 85 will receive different doses of this new vaccine, a standard flu vaccine, or COVID-19 vaccine. The study will assess any side effects or health issues, and additional blood samples will be collected at specific times to evaluate how well participants bodies build protection against the flu and COVID-19.

Interventions

BIOLOGICALInvestigational mRNA Seasonal Flu/COVID-19 Combination (Flu/COVm) Vaccine

Flu/COVm Vaccine with multiple dose levels (Dose Level 1, Dose Level 2, and Dose Level 3), will be administered via single intramuscular injection.

License Seasonal Influenza Vaccine will be administered as a single intramuscular dose.

Licensed COVID-19 Vaccine will be administered as a single intramuscular dose.

Sponsors

GlaxoSmithKline
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Masking description

This is an observer-blind study.

Eligibility

Sex/Gender
ALL
Age
65 Years to 85 Years
Healthy volunteers
No

Inclusion criteria

1. Participants, who, in the opinion of the investigator, can and will comply with the requirements of the protocol independently or with the assistance of the caregiver. 2. Informed consent obtained from the participant prior to performance of any study-specific procedure. 3. A male or female 65 to 85 years of age (YoA) (inclusive) at the time of screening. 4. Healthy participants or medically stable patients as established by medical history and clinical examination. 5. Other protocol-defined inclusion criteria may apply.

Exclusion criteria

1. Any clinically significant laboratory abnormality. 2. History of symptomatic influenza/ SARS-CoV-2 infection confirmed by local health authority-approved testing methods within 180 days (for influenza) or 90 days (SARS-CoV-2 infection) prior to study intervention administration. 3. History of Guillain-Barré syndrome (GBS) within 6 weeks of receiving any vaccine. 4. 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. 5. Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required). 6. 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. 7. History of any reaction or hypersensitivity likely to be exacerbated by any component of the study intervention(s). 8. Acute or unstable chronic conditions, clinically significant pulmonary, cardiovascular, or renal functional abnormality, as determined by physical examination and/or laboratory screening tests. 9. History of hypersensitivity or allergic reaction to any previous influenza or COVID-19 vaccine. 10. History of hypersensitivity or allergic reaction to any previous mRNA vaccine. 11. Administration of any influenza vaccine within 181 days before the study intervention administration (Day -180 to Day 1) or planned administration within 28 days (Day 29) after the study intervention administration. 12. Administration of a SARS-CoV-2 antigen-containing vaccine in the period starting 91 days before the study intervention administration (Day -90 to Day 1) or planned administration within 28 days (Day 29) after the study intervention administration. 13. Administration of any mRNA-based vaccine in the period starting 29 days before the study intervention administration (Day -28 to Day 1) or planned administration within 28 days (Day 29) after the study intervention administration. 14. Administration of any other vaccine not foreseen by the study protocol in the period starting 29 days (Day -28 to Day 1) before the study intervention administration or planned administration within 28 days (Day 29) after the study intervention administration. 15. Other protocol-defined

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants with an Increase in Toxicity Grade of Laboratory Value Abnormalities Following Administration of the Study InterventionDay 1 to Day 3The assessed toxicity grades for laboratory value abnormalities will be defined as follows: Grade 1 = Mild, Grade 2 = Moderate, Grade 3 = Severe, and Grade 4 = Potentially life-threatening.
Number of Participants with an Increase in Toxicity Grade of Laboratory Value Abnormalities following Administration of Study InterventionDay 1 to Day 8
Number of Participants with Solicited Administration Site Adverse Events (AEs)Day 1 to Day 7The solicited administration site AEs considered are pain, redness, swelling and lymphadenopathy.
Number of Participants with Solicited Systemic AEsDay 1 to Day 7The solicited systemic AEs considered are fever, headache, fatigue, myalgia, arthralgia and chills.
Number of Participants with Unsolicited AEsDay 1 to Day 28An 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.
Number of Participants with Serious Adverse Events (SAEs)Day 1 to Day 181A 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.
Number of Participants with Adverse Events of Special Interest (AESIs)Day 1 to Day 181The following events are considered as AESI in this study: severe hypersensitivity reactions within 24 hours after study intervention administration, Aminotransferase elevation; myocarditis/pericarditis within 6 weeks after study intervention administration and potential immune-mediated diseases (pIMDs).
Number of Participants with Medically Attended Adverse Events (MAAEs)Day 1 to Day 181A 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.

Secondary

MeasureTime frame
Geometric Mean Titer (GMT) Of Antigen 1 TiterAt Day 29
Percentage of Participants with Antigen 1 Seroconversion Rate (SCR)Day 1 to Day 29
Percentage of Participants with Antigen 1 Seroprotection Rate (SPR)At Day 1 and Day 29
Geometric Mean Increase (GMI) of Antigen 1 TiterDay 1 to Day 29
GMT Of Antigen 2 TiterAt Day 29
Percentage of Participants with Antigen 2 SCRDay 1 to Day 29
GMI of Antigen 2 TiterDay 1 to Day 29
GMT ratio of serum neutralization titers against pseudovirus bearing spike from SARS-CoV-2 vaccine matched variant(s)At Day 29
Percentage of participants with seroresponse of neutralization titers against pseudovirus bearing spike from SARS-CoV-2 vaccine matched variant(s)Day 1 to Day 29
GMI of neutralization titers against pseudovirus bearing spike from SARS-CoV-2 vaccine matched variant(s)Day 1 to Day 29

Countries

United States

Contacts

CONTACTUS GSK Clinical Trials Call Center
GSKClinicalSupportHD@gsk.com877-379-3718
CONTACTEU GSK Clinical Trials Call Center
GSKClinicalSupportHD@gsk.com+44 (0) 20 89904466

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jul 1, 2026