Immunogenicity, reactogenicity and safety of two-dose versus three-dose (standard care) hepatitis B immunisation of healthy adolescents aged 11–15 years: A randomised controlled trial

This trial assessed the immunogenicity, safety and reactogenicity of a two-dose hepatitis B immunisation regimen (thiomersal-free Engerix-B™ 20 μg HBsAg doses 6 months apart) compared to the standard three-dose vaccination regimen (preservative-free Engerix-B™ 10 μg HBsAg doses, 0, 1, 6 month dose schedule) in healthy adolescents aged 11–15 years. Subjects were randomly assigned (2:1 ratio) to one of the two regimens (258 to the two-dose [20 μg] and 126 to the three-dose [10 μg] regimen) (Study ID 103860/280). One month after the final vaccine dose, the seroprotection (anti-HBs ≥10 mIU/ml) rate in the two-dose (20 μg) group (233/241 individuals −96.7% seroprotected) was non-inferior to the seroprotection rate in the three-dose (10 μg) group (111/113 individuals −98.2% seroprotected). Both regimens were shown to be safe and well tolerated. Two doses of Engerix-B™ (20 μg HBsAg) could be considered as an alternative to standard three-dose Engerix-B™ (10 μg HBsAg) immunisation for adolescents aged 11–15 years.