Immunogenicity and safety of a combined hepatitis A and B vaccine administered concomitantly with either a measles–mumps–rubella or a diphtheria–tetanus–acellular pertussis-inactivated poliomyelitis vaccine mixed with a Haemophilus influenzae type b conju

Two studies were undertaken to investigate the concomitant administration of combined hepatitis A/B vaccine with a diphtheria–tetanus–acellular pertussis-inactivated poliomyelitis vaccine mixed with Haemophilus influenzae vaccine (DTPa-IPV/Hib), or with a measles–mumps–rubella vaccine (MMR), during the second year of life. On completion of the vaccination course, all subjects were seropositive or seroprotected against all antigens except for one subject who was seronegative for anti-PT. Seropositivity and seroprotection rates for all other antibodies were comparable to reference values for each vaccine component, indicating that the immunogenicity of MMR, DTPa-IPV/Hib and combined hepatitis A/B vaccines is not impaired by co-administration. All vaccines were well tolerated.