A phase III randomized study: Immunogenicity and safety of a quadrivalent meningococcal conjugate vaccine in healthy adults, adolescents, and children in India and healthy adolescents and children in South Africa.

BACKGROUND

MenACYW-TT is a quadrivalent meningococcal conjugate vaccine approved for individuals aged ≥6 weeks. This Phase III study evaluated the immunogenicity and safety of a single dose of MenACYW-TT versus MenACYW-DT and MenPS-ACWY in healthy adults, adolescents, and children in India and in healthy adolescents and children in South Africa.

METHODS

In total, 1,328 participants were randomized by age into three cohorts (Cohort Ia: adults aged 18-55 years, India [N=198]; Cohort Ib: adults aged ≥56 years, India [N=200]; Cohort II: children and adolescents aged 2-17 years, India [N=465] and South Africa [N=465]). The immunogenicity of vaccines was assessed with a serum bactericidal assay using human complement (hSBA). The primary objective was to demonstrate the non-inferiority of immunogenicity of a single dose of MenACYW-TT versus MenACYW-DT in children and adolescents aged 2-17 years in terms of hSBA titers in India and South Africa.

RESULTS

The primary objective was met. The non-inferiority of MenACYW-TT versus MenACYW-DT was demonstrated on post-vaccination Day 30 in participants aged 2-17 years. The lower limit of the 95% confidence interval for the difference in the percentages of the participants achieving seroprotection (hSBA titers ≥1:8) against all four serogroups was greater than -10%. MenACYW-TT demonstrated robust immunogenicity in adults aged 18-55 years and ≥56 years in India. The rates of solicited injection site and systemic reactions were comparable between the participants who received MenACYW-TT versus licensed comparator vaccines. No vaccine-related serious adverse events, study discontinuations, or deaths were reported.

CONCLUSIONS

A single dose of MenACYW-TT induced non-inferior immune responses and a comparable safety profile versus MenACYW-DT in children and adolescents aged 2-17 years. MenACYW-TT was well tolerated and immunogenic in adults, adolescents, and children in India and in adolescents and children in South Africa.