Hepatitis B vaccination: Half dose recombinant DNA hepatitis B vaccine (B-Hepavac II) is as immunogenic as the full recommended dose in healthy adults

Abstract

Sixty-seven healthy adult volunteers aged 20-40 years with no previous exposure to hepatitis B virus were randomized to receive either a 10 μg or 5 μg dose of recombinant DNA hepatitis B (HB) vaccine (B-Hepavac II) intramuscularly at 0, 1 and 6 months. Two months after the third injection 100% of subjects had seroconverted: 97% of the 10 μg group and 91% of the 5 μg group had antibody to HB surface antigen (anti-HBs) levels greater than 10 iu/L. The geometric mean titres (GMT) of anti-HBs levels at this time were 891 iu/L in the 10 μg dose group and 923 iu/L in the 5 μg dose group. These differences were not significant. Adverse effects included fever and mild pain at the injection site. The reduced dose of 5 μg was as effective as the standard 10 μg dose.