Safety and immunogenicity of a hexavalent DTwP-IPV-HB-PRP∼T vaccine versus separate DTwP-HB-PRP∼T and IPV vaccines in healthy infants in India.

BACKGROUND

Multivalent vaccines containing whole-cell pertussis (wP) antigens combined with established diphtheria (D), tetanus (T), hepatitis B (HB), type b (Hib), and inactivated poliomyelitis (IPV) antigens allow the provision of a high-quality, affordable DTwP-IPV-HB-PRP∼T vaccine.

METHODS

Phase I/II, randomized, active-controlled, open-label study in healthy toddlers (Cohort I) and infants (Cohort II). Toddlers in Cohort I who had completed primary series D, T, P, HB, Hib, and polio vaccination received a booster dose of DTwP-IPV-HB-PRP∼T (N = 30) or DTwP-HB-PRP∼T + IPV (N = 15) vaccines at 15-18 months of age. After satisfactory review of safety data in Cohort I, infants in Cohort II received DTwP-IPV-HB-PRP∼T (N = 100) or DTwP-HB-PRP∼T + IPV (N = 50) at 6-8, 10-12, and 14-16 weeks of age. All infants in Cohort II had received previous oral polio and HB vaccines per country recommendations.

RESULTS

Booster and primary series vaccinations were well tolerated with no clinically significant differences between vaccine groups. Most adverse events were mild and resolved spontaneously; there were no vaccine-related serious adverse events and no deaths. In both vaccine groups, anti-D, anti-T, anti-HB, anti-Hib, and anti-polio 1, 2, and 3 seroprotection was 100% post-booster and post-primary series. For the pertussis antigens, booster response rate was > 86% in both groups. For the primary series, vaccine response rate was slightly higher for DTwP-IPV-HB-PRP∼T than DTwP-HB-PRP∼T + IPV for anti-PT (80.2% and 70.8%) and anti-FHA (81.3% and 68.8%), slightly lower for anti-PRN (72.5% and 81.3%), and similar in each group for anti-FIM (95.6% and 97.9%).

CONCLUSIONS

This study demonstrated a good safety and immunogenicity profile of the hexavalent DTwP-IPV-HB-PRP∼T vaccine for infant primary series vaccination at 6-8, 10-12, and 14-16 weeks of age and booster vaccination at 15-18 months of age and supported progression to the next development phase.