ABSTRACT
BACKGROUND: The meningococcal serogroups A, C, W, and Y tetanus toxoid conjugate vaccine (MenACWY-TT; Nimenrix®; Pfizer Ltd, Sandwich, Kent, UK) is licensed in more than 80 countries worldwide for the prevention of meningococcal disease caused by serogroups A, C, W, and Y in individuals throughout their lifespans. This report summarizes safety data from the MenACWY-TT clinical development program and postmarketing experience. METHODS: Within the clinical study program, reactogenicity data were based on 3 primary studies, including a large pooled analysis across multiple age groups, and long-term safety data were derived from 3 studies evaluating long-term antibody persistence. Postmarketing safety data through April 19, 2021, were collected and analyzed in connection with the MenACWY-TT Periodic Safety Update Report. RESULTS: Approximately 32 million doses of MenACWY-TT have been administered worldwide, with more than 21,530 additional individuals receiving MenACWY-TT as part of clinical trials. The safety profile of MenACWY-TT was consistent between the clinical study program and the postmarketing experience, as well as with other licensed meningococcal vaccines. The most commonly observed adverse events (AEs) were pyrexia/fever, headache, injection site pain/reactions, nausea/vomiting, and fatigue; serious AEs were rare relative to the number of doses administered. Several cases of serogroup replacement/lack of efficacy were observed in the 1-year postmarketing period but did not appear to be related to MenACWY-TT use. CONCLUSION: Extensive data derived from clinical trials and postmarketing experience indicate a consistently favorable safety profile for MenACWY-TT across a wide range of age groups.