Tetanus toxoid conjugate vaccines have been shown to be safe and immunogenic in non-pregnant as well as pregnant women (167–169) Antibody responses have been dose-dependent and elicited opsonophagocytic activity against matched GBS serotypes in vitro (167–169) In Phase II studies, administration of a second dose of a trivalent CPS-CRM197 vaccine candidate in non-pregnant subjects shows seroconversion with >8 μg/mL CPS type-specific IgG in >94% of participants for each serotype (Ia, Ib, and III). The gene discussed is CAD; the disease is tetanus.