Immunogenicity and safety of the quadrivalent meningococcal ACWY-tetanus toxoid conjugate vaccine (MenACWY-TT) in splenectomized or hyposplenic children and adolescents: Results of a phase III, open, non-randomized study.

•Anatomic/functional asplenia increases the risk of meningococcal disease.•We evaluated immunogenicity of 1 and 2 MenACWY-TT doses in high-risk 1–17-year-olds.•We observed similar rSBA/hSBA vaccine responses in the high-risk and control groups.•Humoral immune response did not seem to be impacted in high-risk patients.•2 doses of MenACWY-TT had a comparable safety profile in both groups.