Clinical trial of hepatitis B vaccine in the families of HBV carriers.

A hepatitis B (HB) vaccine was given to 75 subjects who were hospital workers and families of HBeAG positive carriers, and the anti-HBs response to the vaccination was studied. Subjects younger than 10 years of age were given 10 micrograms of vaccine and those 10 years or older, 20 micrograms. The second and third injections were given 4 and 24 weeks after the first. Twenty-eight weeks after the first vaccination, anti-HBs was detected in 70 of the 75 subjects (93%). The anti-HBs response was more marked in females and in younger people, but the differences between males and females and between the younger and older groups were not statistically significant. In subjects under 10 years of age, an adequate anti-HBs response was obtained with 10 micrograms of HBsAg protein. There was no clear correlation between the anti-HBs response and the HLA haplotype, because even the siblings who showed the same low anti-HBs response did not have the same HLA haplotype in common, and a difference was observed in the anti-HBs response even among siblings who had the same two HLA haplotypes.