EVALUATION OF AN ACELLULAR PERTUSSIS, DIPHTHERIA, TETANUS, INACTIVATED POLIOVIRUS, HIB-CONJUGATE COMBINED VACCINE (PENTAXIM™) AT 2, 4, AND 6 MONTHS OF AGE PLUS HEPATITIS B VACCINE AT BIRTH, 2, AND 6 MONTHS OF AGE IN INFANTS IN THAILAND

The objective of this study was to evaluate the immunogenicity and safety of a pentavalent vaccine (Pentaxim (TM)) containing diphtheria, tetanus, acellular pertussis, inactivated poliovirus, and Hib polysaccharide-conjugate (DTaP-IPV//PRP similar to 7) antigens, in Thai children. One hundred eighty-six infants who had received a hepatitis B vaccine at birth were given a pentavalent vaccine at 2, 4 and 6 months of age and a hepatitis 13 vaccine concomitantly at 2 and 6 months of age. Immunogenicity was high for each vaccine antigen The study vaccine was well tolerated and side effects were few After the third dose, 100% of subjects had an anti-PRP >= 0.15 mu g/ml and 96.5% >= 1.0 mu g/ml; the anti-PRP GMT was 9 53 mu g/ml. Seroprotective rates for diphtheria and tetanus (>= 0 01 IU/ml) were 994% and 100%, respectively, and 100% for all three poliovirus types (>= 8 1/dil U) The vaccine response rates to pertussis antigens (a 4-fold increase in antibody titer were 94.1% for PT and 93.0% for FHA. The DTaP-IPW/PRP similar to T vaccine given at 2, 4 and 6 months of age concomitantly with a monovalent hepatitis B vaccine, was well tolerated and highly immunogenic for primary immunization of infants in Thailand.