ABSTRACT
Objective The aim of this study was to demonstrate the immunogenicity and safety of diphtheria, tetanus, pertussis (acellular, component) , poliomyelitis (inactivated) vaccine (adsorbed) and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV//PRP-T) combined vaccine compared with commercially available DTaP (diphtheria, tetanus and pertussis), Haemophilus influenzae type b (Hib), tetanus conjugate and IPV monovalent vaccine. Methods Subjects were randomly divided into three groups, Group A and Group B were DTaP-IPV//PRP-T combined vaccine (PENTAXIMTM) vaccinated at 2,3,4 months of age or 3,4, 5 months of age respectively; Group C was commercially available DTaP. Hib tetanus conjugate (Act-HIBTM) and IPV (IMOVAX PolioTM) vaccines vaccinated at 3,4, 5 months of age. All groups received booster dose at 18 to 20 months of age, with antibody titers tested. Non-inferiority analysis was demonstrated in terms of seroprotection / seroconversion rates between Group A, Group B respectively and Group C. Safety information was collected after each vaccination to assess the safety of investigational vaccines. Results The non-inferiority of DTaP-IPV//PRP-T combined vaccine vaccinated at 2,3,4 or 3,4, 5 months of age versus DTaP, Hib tetanus conjugate and IPV vaccine was demonstrated for all vaccine antigens in both primary and booster phases in terms of seroprotection/seroconversion rates. DTaP-IPV//PRP-T combined vaccine was well tolerated. The rate of solicited/unsoliciated severe adverse reactions was very low and similar to the control vaccines. Conclusion DTaP-IPV//PRP-T combined vaccine was highly immunogenic with good safety profile in Chinese infants, which was comparable to the commercially available control vaccines.