A first-in-human, Phase 1 trial assessing the safety and immunogenicity of an investigational nanoparticle influenza vaccine designed to provide long-lasting protection against multiple flu virus strains has begun at the National Institutes of Health Clinical Center in Bethesda, Maryland. Healthy participants 18 to 50 years old will receive either a licensed seasonal influenza vaccine or the experimental vaccine, FluMos-v1. Scientists from NIH’s National Institute of Allergy and Infectious Diseases (NIAID) developed FluMos-v1 to stimulate antibodies against multiple influenza virus strains by displaying part of the influenza virus hemagglutinin (HA) protein on self-assembling nanoparticle scaffolds. Alicia T. Widge, M.D., of NIAID’s Vaccine Research Center (VRC), is the principal investigator of the NIAID-sponsored single-site trial.