Comparative study of the immunogenicity and safety of two doses of recombinant hepatitis B vaccine in healthy adolescents.

Purpose: A prospective, two-armed, open-label, randomized trial was performed to compare the geometric mean titers (GMT), seroprotection (SP) and seroconversion (SC) rates found after administration of two doses of recombinant hepatitis B vaccine.

Methods: Recombinant hepatitis B vaccine 10 or 20 micrograms was administered IM at 0, 1, and 6 months in healthy adolescents.

Results: Volunteers who received either dose of the vaccine had similarly high seroconversion and seroprotection rates at all visits. At Month 8, both doses of the vaccine were highly immunogenic with GMTs of 1989 mIU/mL (10 micrograms dose) and 7672 mIU/mL (20 micrograms dose) and nearly equivalent SP rates (97% and 99% in the 10 and 20 micrograms dose groups, respectively). The geometric mean titers of seroconverters at Months 3, 6 and 8 were significantly greater in the 20 micrograms group as compared to the 10 micrograms group (p < or = 0.003). Both doses were well-tolerated, with injection site pain the most common reported adverse event. Injection site pain was reported significantly (p = 0.004) more by volunteers who received the 20 micrograms dose (10.7%) compared with volunteers who received the 10 micrograms dose (3.8%).

Conclusion: Vaccination with 10 micrograms of recombinant hepatitis B vaccine may provide a clinically effective and economical alternative to the use of the 20 micrograms dose in healthy adolescents.