Immunogenicity, Safety, and Tolerability of a Plant-Derived Quadrivalent VLP Influenza Vaccine in Elderly Adults

This randomized, observer-blind, multicenter, Phase 2 study will be conducted at multiple sites across the United States and Canada. The influenza strain composition of the Quadrivalent VLP Vaccine used in this study includes 2 influenza A virus strains (A/California/7/2009 \[H1N1\] and A/Switzerland/9715293/2013 \[H3N2\]) and 2 influenza B virus strains (B/Phuket/3073/2013 \[Yamagata lineage\] and B/Brisbane/60/2008 \[Victoria lineage\]), based on the 2015-2016 recommended World Health Organization (WHO) strains for vaccination in the Northern hemisphere. Approximately 1000 elderly male and female subjects, aged 65 years or older, will be randomized in a 1:1:1:1 ratio to 1of 4 parallel treatment groups such that 500 subjects receive Quadrivalent VLP Vaccine (250 each for the 30 µg/strain and 60 µg/strain groups), 250 subjects receive FluLaval® Tetra (15 µg/strain) and 250 subjects receive Fluzone® HD (60 µg/strain). Subjects in each group will be stratified into 2 age strata: 65 to 74 years and 75 years old and older, where 70 % of subjects will be enrolled into the 65 to 74 years old age group and 30 % into the 75 years old or older group. Subjects will participate in this study for approximately 8 months, during which 5 visits will be scheduled, and phone contact will be made on Day 1, Day 8, and every 2 months thereafter for up to 6 months post-Day 21 visit (Day 201). Blood samples will be collected for immunogenicity analyses at Days 0 and 21 for all subjects. Safety laboratory assessments will be performed at Screening, on Day 3 and within 48 hours of Day 3 results availability, for grade 3 or grade 4 abnormalities or if deemed necessary by the investigator or early termination. Subsequent follow-up of clinically significant laboratory abnormalities will be done according to the investigator's discretion.. Subjects will be monitored throughout the study for safety, including the reporting of solicited local and systemic reactions.