Meningococcal vaccine A,C,W135,Y: conjugated to tetanus toxoid

A meningococcal vaccine conjugated to protein CRM 197 (Menveo) is the standard vaccine for immunisation against invasive meningococcal infections caused by serogroups A, C, W135 andY, beginning at age 2 years. Nimenrix, another vaccine against meningococcal groups A, C,W135 and Y, conjugated to tetanus toxoid, was authorised for use in the European Union, starting at age 1 year. The two tetravalent meningococcal conjugate vaccines have not been compared in head-to-head trials. Four immunogenicity studies compared the tetravalent conjugate vaccine Nimenrix with an unconjugated tetravalent meningococcal vaccine in children and adults aged 2 to 55 years. The results showed that Nimenrix was more immunogenic than the unconjugated vaccine. Two immunogenicity studies showed that Nimenrix was at least as immunogenic as monovalent (group C) meningococcal conjugate vaccines in children aged from 1 to 2 years and from 2 to 10 years. In one study, prior vaccination with an unconjugated tetravalent meningococcal vaccine had little impact on the immunogenicity of a booster dose of the conjugate vaccine Nimenrix. Concomitant administration with other vaccines does not affect the immunogenicity of Nimenrix. Nimenrix causes more frequent local and systemic adverse reactions than the unconjugated tetravalent meningococcal vaccine and monovalent group C meningococcal conjugate vaccines. In children over 2 years of age, Nimenrix has no advantages over Menveo for vaccination against meningococcal serogroups A, C, W135 andY. In contrast, between the ages of 1 and 2 years, Nimenrix is the only vaccine with established immunogenicity. In addition, it has an acceptable harm-benefit balance.