3. A Review of the Clinical Development of MenACWY-TT, a Quadrivalent Meningococcal Vaccine Conjugated to Tetanus Toxoid, in Adolescents

Background As a peak in meningococcal disease often occurs during adolescence, meningococcal vaccination programs are available for this age group in various regions across the globe. Quadrivalent meningococcal (MenACWY) conjugate vaccines are being incorporated in an increasing number of programs in response to changing meningococcal serogroup epidemiology. MenACWY-TT (Nimenrix®) is a MenACWY conjugate vaccine available in the European Union and 50 other countries for preventive vaccination of serogroup A, C, W, and Y disease (Figure 1). MenACWY-TT is licensed in some countries as a 2-dose primary series in individuals as young as 6 weeks of age, while a single dose may be given to previously unvaccinated individuals ≥ 6 months of age, adolescents, and adults. Here, we provide an overview of the 3 primary and 5 extension studies evaluating the clinical development of MenACWY-TT in adolescents (Table 1). Figure 1. Global Registration Status of MenACWY-TT (Nimenrix®) in Adolescents Table 1. Pivotal Clinical Studies of MenACWY-TT (Nimenrix®) Supporting Licensure in Adolescents Methods Immunogenicity and safety data from these 8 clinical studies are summarized. Results Across studies, MenACWY-TT antibody responses against all vaccine serogroups were comparable to those of other MenACWY vaccines 1 month post vaccination (Table 1). Antibody responses to MenACWY-TT persisted for up to 10 years in those vaccinated during adolescence. A MenACWY-TT booster given 10 years after primary meningococcal vaccination in early childhood or adolescence elicited robust antibody responses. MenACWY-TT had an acceptable safety profile, with reactogenicity events most commonly reported. Reactogenicity profiles with MenACWY-TT booster were similar to those seen after primary MenACWY-TT. Conclusion The MenACWY-TT clinical study program demonstrated the immunogenicity and safety of primary and booster dosing in adolescents. Immune responses persisted through 10 years after primary vaccination. Funding Pfizer. Disclosures Paula Peyrani, MD, Pfizer Inc (Employee, Shareholder) Chris Webber, MD, Pfizer Inc (Employee, Shareholder) Cindy Burman, PharmD, Pfizer Inc (Employee, Shareholder) Paul Balmer, PhD, Pfizer Inc (Employee, Shareholder) John L. Perez, MD, MA, Pfizer Inc (Employee, Shareholder)