COMP A RA T IVE EV A LU AT ION OF T WO DIFFERENT INVESTIGA T IONAL MENINGOCOCCAL A BCWY VA CCINE FORMULA T IONS IN ADOLESCENTS AND YO UNG ADUL T S

ABSTRACT Background: Novartis has licensed meningococcal vaccines against serogroups A, C, W and Y(MenACWY-CRM) and serogroup B (4CMenB). We evaluated 2 investigational formulations ofMenABCWY vaccines, with primary objectives to assess their noninferiority compared with thelicensed vaccine for ACWY serogroups and formulation selection based on a desirability index (DI)(Clinicaltrials.gov NCT01272180). Methods: 480 healthy subjects, aged 10–25 years, were randomized to four groups to receiveeither: one of two MenABCWY formulations with full or quarter doses of outer membrane vesicles(OMV), 4CMenB, or Placebo/MenACWY-CRM. Each was given as a 2-dose series at 0 and 2months. A serum bactericidal assay with human complement (hSBA) was used to measureantibodies against serogroups A, C, W, Y and serogroup B test strains at baseline and 30 days afterdose 2; seroresponses and hSBA GMTs were assessed. For MenABCWY vaccines we alsocompared a DI based on immunogenicity (post-vaccine hSBA GMT ratios) and reactogenicityparameters (percentages of doses associated with severe local and severe systemic reactions).