Efficacy of a Plant-derived Quadrivalent Virus-like Particle (VLP) Vaccine in the Elderly

This randomized, observer-blind, active-controlled multicenter, Phase 3 study was conducted at multiple sites. The composition of the Quadrivalent VLP Influenza Vaccine used in this study included a mix of recombinant H1, H3, and two B hemagglutinin proteins expressed as VLPs for the 2018-2019 influenza virus strains. A total of 12,794 healthy male and female participants aged 65 years and older were randomized in a 1:1 ratio into one of two parallel treatment groups, such that 6,396 participants were randomized to receive the Quadrivalent VLP Influenza Vaccine at a dose of 30 μg/strain and 6,398 participants were randomized to receive the comparator. Within the two treatment groups, participants were stratified by site and two age groups (65-74 years of age and 75 years of age and older in a 2:1 ratio). Participants participated in this study for approximately nine months, during which a first visit was scheduled on Day 0 for screening and vaccine administration.