Immunogenicity of COVID-19 Vaccine Co-administration With Influenza Vaccine in Healthy Volunteers

Immunogenicity to SARS-CoV-2 of Co-administering Bivalent mRNA BNT162b2 Booster and Quadrivalent Influenza Vaccine Among Healthy Volunteers: A Pilot Study

This study, a pilot randomized controlled trial, single-blind (outcome assessor), evaluating the immune response (both humoral and cell-mediated) against SARS-CoV-2 and the safety of three different vaccine administration approaches: the SARS-CoV-2 mRNA vaccine alone, the influenza vaccine alone, and the co-administration of both vaccines.

Study Overview

• Status: Completed
• Conditions: COVID - 19
• Intervention / Treatment: Biological: Bivalent mRNA SARS-CoV-2 vaccine; Biological: Quardrivalent influenza vaccine

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• Thailand
  • Songkhla, Thailand, 90110
    • Faculty of Medicine, Prince of Songkla University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Thai adults aged 18-60 years, who have vaccinated COVID-19 and influenza vaccine more than 6 months.
• The subjects are able to and willing to comply with the requirements of the clinical trial program and could complete the 1-month follow-up of the study.
• Individuals who are in good health condition at the time of entry into the trial as determined by medical history, physical examination and clinical judgment of the investigator and meet the requirements of immunization.
• The subject can provide with informed consent and sign informed consent form (ICF).

Exclusion Criteria:

• Have history of influenza or COVID-19 infection within 6 months.
• Have the medical history or family history of convulsion, epilepsy, encephalopathy, and psychosis.
• Be allergic to any component of the research vaccines or used to have a history of hypersensitivity or serious reactions to vaccination.
• History of Guillain-Barré syndrome.
• Women with positive urine pregnancy test, pregnant or breast-feeding, or have a pregnancy plan within six months of after baseline period.
• Have infectious diseases, including HIV and SARS-CoV-2 infection or any symptom of common cold.
• Have history of SARS-CoV-2 infection less than 6 months.
• Having severe chronic diseases or condition in progress cannot be controlled. For example, poor controlled DM and uncontrolled HT.
• Have the history of urticaria 1 year before receiving the investigational vaccine.
• Have known underlying diseases of thrombocytopenia or other coagulation disorders (which may cause contraindications for intramuscular injection).
• Having needle sickness.
• Have the history of immunosuppressive therapy, cytotoxic therapy, or systemic corticosteroids.
• Have received blood products within 4 months before injection of investigational vaccines.
• Under anti-tuberculosis treatment.
• Not be able to follow the protocol, or not be able to understand the informed consent according to the researcher's judgment, due to various medical, psychological, social, or other conditions.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Bivalent mRNA BNT162b2; Administering a booster dose of the bivalent mRNA vaccine BNT162b2.	Biological: Bivalent mRNA SARS-CoV-2 vaccine; Administering a booster dose of the bivalent mRNA vaccine BNT162b2
Experimental: Quardrivalent influenza vaccine; Administering a VaxigripTetra™	Biological: Quardrivalent influenza vaccine; Administering a VaxigripTetra™
Experimental: Co-administration; Co-administering bivalent mRNA vaccine BNT162b2 and VaxigripTetra™	Biological: Bivalent mRNA SARS-CoV-2 vaccine; Administering a booster dose of the bivalent mRNA vaccine BNT162b2; Biological: Quardrivalent influenza vaccine; Administering a VaxigripTetra™

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Geometric Mean (GM) of Interferon-gamma (IFN-γ) Response Against the SARS-CoV-2 Virus at Baseline	IFN-γ response against the SARS-CoV-2 virus, measured by the ELISpot assay	Before vaccination
Geometric Mean (GM) of Interferon-gamma (IFN-γ) Response Against the SARS-CoV-2 Virus at 4 Weeks	IFN-γ response against the SARS-CoV-2 virus, measured by the ELISpot assay	4 weeks post vaccination
Geometric Mean (GM) of IgG Response Against the SARS-CoV-2 Virus at Baseline	IgG response against the SARS-CoV-2 virus, measured by ELISA.	before vaccination
Geometric Mean (GM) of IgG Response Against the SARS-CoV-2 Virus at 4 Weeks	IgG response against the SARS-CoV-2 virus, measured by ELISA.	4 weeks post vaccination

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse event at 1 and 4 weeks	Self-reported adverse events at 1 week and assessed by interview at 4 weeks.	from vaccination to 4 weeks
Geometric mean ratio (GMR) of IgG response against the SARS-CoV-2 virus between pre and 4 weeks post vaccination	IgG response against the SARS-CoV-2 virus, measured by ELISA at day 0 (pre-vaccination) and at 4 weeks , GMR of each arm.	pre-vaccination to 4 weeks post vaccination
Geometric mean ratio (GMR) of Interferon-gamma (IFN-γ) response against the SARS-CoV-2 virus between pre and 4 weeks post vaccination	IFN-γ response against the SARS-CoV-2 virus, measured by the ELISpot assay at day 0 (pre-vaccination) and at 4 weeks , GMR of each arm.	pre-vaccination to 4 weeks post vaccination

Collaborators and Investigators

• Sponsor: Prince of Songkla University
• Investigators: Principal Investigator: Sarunyou Chusri, M.D., Ph.D., Prince of Songkla University

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2024
• Primary Completion (Actual): May 31, 2024
• Study Completion (Actual): May 31, 2024

Study Registration Dates

• First Submitted: February 15, 2025
• First Submitted That Met QC Criteria: February 15, 2025
• First Posted (Actual): February 18, 2025

Study Record Updates

• Last Update Posted (Estimated): December 4, 2025
• Last Update Submitted That Met QC Criteria: November 16, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: immunogenicity; influenza vaccine; co-administration; SARS-CoV-2 vaccine; COVID-19 vaccine; cell-medicated immune response
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Influenza, Human; Immunologic Factors; Physiological Effects of Drugs; Vaccines
• Other Study ID Numbers: REC.66-462-14-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The data will be kept anonymized.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No