Immunogenicity and reactogenicity of a three-dose primary vaccination course with a combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated polio-haemophilus influenzae type b vaccine coadministered with a meningococcal C conjugate vaccine.

AIM: To evaluate the immunogenicity and safety of 3 doses of the combined diphtheria-tetanus toxoids-acellular pertussis-hepatitis B virus-inactivated poliovirus/Haemophilus influenzae type b (DTPa-HBV-IPV/Hib) vaccine (Infanrix hexa) when coadministered with a CRM197-conjugated meningococcal C vaccine (Meningitec) at different injection sites during the same visit or during separate visits.

METHODS

Healthy infants were randomized in an open randomized multicenter study to receive either the DTPa-HBV-IPV/Hib and meningococcal C conjugate vaccines during the same vaccination visit at 2, 4 and 6 months of age (coadministration group) or the DTPa-HBV-IPV/Hib vaccine at 2, 4 and 6 months of age and the meningococcal C conjugate vaccine at 3, 5 and 7 months of age (separate administration group).

RESULTS

The immunogenicity analysis included 452 infants, 228 in the coadministration group and 224 in the separate administration group. One month after primary vaccination, 99.1% of subjects in both groups achieved anti-polyribosylribitol phosphate antibody concentrations >/=0.15 microg/mL. The vaccine response against pertussis antigens was at least 99.1% in both groups. For all other DTPa-HBV-IPV/Hib vaccine antigens, at least 97.8% of all subjects of both groups were seroprotected. In addition, 99.5% of all subjects had meningococcal C bactericidal antibody titers >/=1/8 and 99.1% >/=1/128. Coadministration of both vaccines did not result in an increased local or general reactogenicity compared with separate administration.

CONCLUSION

Coadministration of the combined DTPa-HBV-IPV/Hib vaccine and the meningococcal C conjugate vaccine during the same vaccination visit was immunogenic and safe.