Available data on immunogenicity and safety of meningococcal B vaccine in children and adolescents

Background Neisseria meningitidis serogroup B is the most common etiological agent of meningococcal invasive disease in Europe. A multicomponent vaccine against meningococcal serogroup B (4CMenB) has been licensed since 2013 in different European countries, with various immunization schedules. We are conducting a meta-analysis aimed to assess the immunogenicity and safety of 4CMenB on children and adolescents. Methods We searched MEDLINE, Scopus and Clinicaltrals.gov databases for all published and unpublished randomized clinical trials (RCTs) comparing the immunogenicity and safety of 4CMenB against controls. We plan to perform head-to-head and proportion meta-analyses. Results We retrieved a total of 22 RCTs published between 2010 and 2016. 16 trials met the inclusion criteria: 12 included healthy children aged 2-60 months, 4 focused on adolescents aged 11-17 years. 2 out of 16 studies compared the immunogenicity and safety of 4CMenB against placebo, one against placebo followed by the MenACWY vaccine, one against MenC vaccine, two against routine vaccinations, two studies were lot-to-lot comparisons and all the others compared 4CMenB with the previously developed recombinant Meningococcal B vaccine (rMenB). In all studies, immunogenicity data were based on the analysis of bactericidal antibody titers against meningococcal serogroup B strains, performed 1 month after the final dose. 5 studies evaluated the persistence of bactericidal antibodies in preschool children. The strains used by all authors to asses immunogenicity were 44/76-SL, 5/99 and NZ 98/254. Conclusions Several studies have been published on the immunogenicity and safety of 4CMenB on children and adolescents, but they are heterogeneous in terms of populations and schedules. Data on the persistence of bactericidal antibodies are scarce. Key messages: Available studies on meningococcal B vaccine are extremely heterogeneous and a quantitative synthesis of available evidence is challenging Additional studies are needed to address the persistence of immunogenicity in vaccinated children, including trials sponsored by non-industry agencies