Recent advances in the development of a vaccine to target meningococcal serogroup X

Serogroup X has emerged as an important cause of invasive meningococcal disease across Sub-Saharan Africa. Recent advances in serogroup X vaccines were reviewed.

Early vaccine development efforts focused on outer membrane vesicle-based approaches. The growing epidemiological importance of serogroup X accelerated the development of serogroup X conjugate vaccines. Building on the success of MenAfriVac, PATH and the Serum Institute of India Pvt. Ltd. developed NmCV-5 (MenFive), the first pentavalent meningococcal conjugate vaccine targeting serogroup X. NmCV-5 achieved World Health Organization (WHO) pre-qualification in 2023, enabling deployment across Sub-Saharan Africa. A second pentavalent vaccine, EuNmCV-5, developed by Eubiologics is advancing through clinical development, while an additional candidate from Sinovac Biotech is entering early phase evaluation. These advances representative a major milestone in meningococcal disease prevention.

Within the last fifteen years significant vaccine developments have been made to combat serogroup X. With NmCV-5 attaining WHO pre-qualification, strategies for its implementation within Sub-Saharan Africa are being devised. Only one vaccine is currently available in Sub- Saharan Africa, but trials of a second pentavalent ACWYX conjugate vaccine are ongoing. Carriage studies and disease surveillance are crucial to monitor serogroup X vaccine effectiveness.