Immunogenicity and reactogenicity of a combined fully liquid DTPw–HepB–Hib pentavalent vaccine in healthy infants: no clinically relevant impact of a birth dose of hepatitis B vaccine

SummaryObjectivesIn this open-label, non-randomized phase II study, the safety and immunogenicity of a fully liquid diphtheria–tetanus–whole cell pertussis–hepatitis B–Haemophilus influenzae type b (DTPw–HepB–Hib) combination vaccine (Quinvaxem®) were assessed in infants who had or had not received a birth dose of hepatitis B (HepB) vaccine.Study designTwo groups of infants, ‘HepB at birth’ (n = 110) and ‘no HepB at birth’ (n = 108), were enrolled and received a primary vaccination course using a 2–4–6 months schedule.ResultsSeroprotection/seroconversion rates of >95% were achieved against all antigens included in the combination vaccine for both study groups. Although significantly higher anti-hepatitis B virus (p < 0.001) and anti-tetanus (p = 0.031) antibody titers were achieved in group ‘HepB at birth’ when compared with group ‘no HepB at birth’, the proportion of ‘no HepB at birth’ subjects achieving protective titers was non-inferior to the proportion of subjects in group ‘HepB at birth’. The birth dose of HepB vaccine did not seem to influence the safety pattern of the DTPw–HepB–Hib combination vaccine.ConclusionsThe present study demonstrated that the fully liquid DTPw–HepB–Hib vaccine was safe and immunogenic when administered using a 2–4–6 months immunization schedule, regardless of whether or not infants had received a dose of HepB vaccine at birth.