Modeling the persistence of 4CMenB vaccine protection against real world meningococcal B disease in adolescents.

The efficacy of the four-component 4CMenB vaccine is measured through the serum bactericidal antibody (SBA) assay on four meningococcal B (MenB) indicator strains. However, they are not epidemiologically relevant for disease, thus the real-world persistence of 4CMenB protection remains uncertain. Several mathematical models of waning immunity were fitted on longitudinal SBA data from persistence studies in adolescents, with up to eight years follow-up after 4CMenB priming vaccination. The best model was used to predict protection from indicator strains. MenB typing data from the United States were used to integrate antigen-level curves and predict the persistence of protection from real-world MenB strains, considering synergies between antigens. Models show that protection and its evolution varied by antigen and that 4CMenB likely elicits antibody-producing long-lived plasma cells. 4CMenB protection from real-world MenB disease persisted at 61.5% four years post-priming and 70.5% four years post-booster. This evidence could support decision-making on adolescent immunization programs.