Phase IIc randomized double-blind active-controlled study of an ACYW135 meningococcal conjugate vaccine in children aged 12 to 23 months

Phase 2, randomised, double-blind trial of A, C, Y, W135 meningococcal polysaccharide vaccine in meningococcal meningitis (2 arms), sponsored by Sino Biopharmaceutical Limited. Primary endpoint: Seroconversion rate and geometric mean titer for serogroups A, C, Y, and W135 in baseline-seronegative participants 30 days after completion of primary immunization. Started Dec 2025; status: active.