On Sept. 23, 2021, Novavax announced publication of complete results from a pivotal Phase 3 clinical trial of NanoFlu, its recombinant quadrivalent seasonal influenza vaccine candidate with Matrix-M adjuvant, in The Lancet Infectious Diseases.

The trial evaluated the immunogenicity and safety of NanoFlu in older adults compared to a leading U.S.-licensed quadrivalent influenza vaccine. In the complete analysis, NanoFlu was well-tolerated and produced significantly enhanced humoral and cellular immune responses versus the comparator vaccine.

Novavax previously announced that NanoFlu achieved the trial’s primary endpoints, demonstrating non-inferior immunogenicity to Fluzone^® Quadrivalent against all four influenza virus strains included in the vaccine, while also showing both enhanced wild-type hemagglutination-inhibiting antibody responses against homologous strains (22-66% increased) and six heterologous A/H3N2 strains (34-46% increased) as compared to Fluzone Quadrivalent.

Additionally, NanoFlu showed potent induction of polyfunctional antigen-specific CD4+ T-cells against A/H3N2 and B/Victoria strains, with a 126–189% increase in various post-vaccination cell-mediated immunity markers as compared to Fluzone Quadrivalent.

The paper, ‘Comparison of the safety and immunogenicity of a novel Matrix-M-adjuvanted nanoparticle influenza vaccine with a quadrivalent seasonal influenza vaccine in older adults: a phase 3 randomised controlled trial,’ was previously posted to the medRxiv preprint server in August 2020.