Background: Because meningococcal disease epidemiology is unpredictable, vaccination remains critical. Recently, increased numbers of MenW/Y cases prompted many countries to update national immunisation programme (NIP) recommendations from monovalent to quadrivalent vaccines. MenACWY-TT (Nimenrix®, Pfizer Europe) was approved in 2012 and licensed in >80 countries. Herein, clinical and real-world data supporting MenACWY-TT use in NIPs are described.
Clinical data: MenACWY-TT immunogenicity and safety were evaluated in several phase 2− 3 trials among participants ≥6-weeks-old−≥55-years-old. These extensive clinical data support robust immune responses across age groups and in immunocompromised individuals, and coadministration with other vaccines, with an acceptable and similar safety profile across age groups. MenACWY-TT was also evaluated against licensed meningococcal vaccines, showing similar or higher antibody responses against all serogroups.
MenACWY-TT’s posology reflects these clinical data, including a phase 3 trial demonstrating that an infant 3- and 12-month schedule elicited protective serum bactericidal antibody titres. Therefore, MenACWY-TT is approved as an infant 2-dose series from 6-weeks-old and 1-dose primary series from 6-months-old, with a booster given in their second year of life. Single-dose posology is approved in ≥12-month-olds. Evidence of antibody persistence up to 10 years after primary vaccination was evaluated from extension trials across all age groups.
Real-world data: MenACWY conjugate vaccine inclusion in NIPs is often based on evolving epidemiology. The Czech NIP is updated regularly and includes MenACWY-TT for toddlers and adolescents/young adults, allowing use in high‑risk groups in response to the actual epidemiological situation. French and German NIPs were also updated recently to include MenACWY vaccines.
Real‑world evidence from multiple countries (Chile, England, Netherlands, Australia) demonstrates that MenACWY-TT implementation is associated with marked and sustained reductions in meningococcal disease, particularly MenW, in both vaccinated and unvaccinated populations, consistent with herd protection. For instance, MenACWY-TT’s introduction into the Dutch toddler/adolescent NIP in 2018 led to substantial declines in meningococcal disease of up to 100% in adolescents, 85% in vaccine‑eligible groups, and 50% in non‑eligible groups within 2 years.
Conclusion: MenACWY-TT shows consistent, evidence‑based, long-term robust immune persistence, safety, and real‑world effectiveness across all age groups, reinforcing its value as a quadrivalent meningococcal vaccine option.
Sponsor: Pfizer.