A dose-range study assessing immunogenicity and safety of one dose of a new candidate meningococcal serogroups A, C, W-135, Y tetanus toxoid conjugate (MenACWY-TT) vaccine administered in the second year of life and in young children

Meningococcal disease incidence is highest in young children, yet a tetravalent conjugate vaccine is currently not available for this age group. This study evaluated a single dose of four different ACWY-TT conjugate vaccine formulations in 240 toddlers (12–14 months) and 268 children (3–5 years) compared to licensed age-appropriate control vaccines. In toddlers, rSBA-MenC GMTs for the selected formulation were statistically higher than after monovalent-MenC-conjugate vaccine. In children, rSBA-GMTs against each serogroup were statistically higher than after tetravalent polysaccharide vaccine. The safety profile was comparable to licensed controls. The new ACWY-TT conjugate vaccine promises high seroprotection levels against meningococcal disease from 1 year of age.