Comparative Immunologic Mechanisms and Microbiome Interactions Following Different Influenza Vaccine Formulations in Older Adults

Overview

This prospective, randomized, open-label clinical study aims to evaluate the immunogenicity and underlying immune mechanisms of different influenza vaccine formulations in adults aged ≥65 years. Additionally, the study investigates the role of the gut microbiome in modulating vaccine-induced immune responses and durability.

Despite high influenza vaccination coverage among older adults in Korea, vaccine effectiveness remains suboptimal, even during well-matched seasons. Immunosenescence and microbiome dysbiosis are believed to contribute to reduced vaccine responsiveness. This study will: * Compare immune responses induced by standard-dose, MF59-adjuvanted, and high-dose influenza vaccines * Characterize cellular and humoral immune mechanisms * Analyze gut microbiome composition and function using metagenomic approaches * Identify microbiome-derived biomarkers associated with vaccine responsiveness and durability

Conditions

Interventions

Eligibility

Locations (1)

Outcomes