Comparison study of combined DTPw-HB vaccines and separate administration of DTPw and HB vaccines in Thai children.

The safety, immunogenicity and tolerability of two different DTPw-HBV combination vaccines, containing 5 and 10 microg of HBsAg; were investigated in comparison with separate administration of DTPw and HBV (10 microg of HBsAg). A three dose primary vaccination course at 2, 4 and 6 months of age was followed by a booster dose at 18 months. All vaccines were safe and well tolerated. The DTPw-HBV combination vaccine containing 10 microg of HBsAg elicited significantly higher anti-HBs titres than the other two vaccines after the primary and booster vaccination course. All vaccines elicited a high response against the other components. Based on these results, DTPw-HBV (10 microg HBsAg) was the most effective vaccine at this schedule.

The new DTPw-HBV-Hib combination vaccine can be used at the who schedule with a monovalent dose of hepatitis B vaccine at birth.

An open, randomized, clinical trial was conducted in order to assess the reactogenicity and immunogenicity of DTPw-HBV and Haemophilus influenzae type b (Hib) vaccines when given either as a mixed administration or as separate concomitant injections using the WHO schedule at 6, 10 and 14 weeks of age, following a dose of HBV at birth. There were no clinically relevant differences in the immune response to any component between the mixed and separate administrations. In fact the anti-tetanus GMTs were significantly higher (p=0.002) in mixed administration (3.9 IU/ml) compared with the separate administration (1.9 IU/ml). However although all subjects achieved anti-PRP titers > or = 0.15 microg/ml, higher anti-PRP GMTs were seen in the group receiving the separate administration. Importantly, the addition of Hib did not adversely alter the reactogenicity profile of DTPw-HBV. This report which demonstrates that this novel combination can be used in WHO recommended schedule.