Evaluation of the Safety and Immunogenicity of Influenza and COVID-19 Combination Vaccine

This is a randomized, observer-blinded, Phase 1/2 study evaluating the safety and immunogenicity of a quadrivalent hemagglutinin (HA) nanoparticle influenza vaccine (qNIV) and severe acute respiratory syndrome coronavirus 2 (SARSCoV2) recombinant spike (rS) nanoparticle combination vaccine with Matrix-M1™ adjuvant; this combination vaccine is referred to as Influenza COVID-19 Combination (ICC) vaccine. The study will enroll approximately 640 healthy (based on history and physical examination) adult male and female participants 50 to 70 years of age, inclusive, targeting participants who are baseline seropositive (either previously infected with SARS-CoV-2 ≥ 8 weeks prior to enrollment, or have been previously immunized against SARS-CoV-2 with a completed regimen of an authorized vaccine at ≥ 8 weeks prior to enrollment). Randomization will be stratified on age ≥ 50 to ≤60 or ≥ 60 to ≤ 70 years to distribute the proportions of each age stratum evenly across vaccine groups.