Antibody responses of healthy infants to a recombinant hepatitis B vaccine administered at two, four, and twelve or fifteen months of age.

Hepatitis B vaccine was administered to healthy infants on two investigational schedules that fall within ranges recommended by the U.S. Public Health Service Advisory Committee on Immunization Practices and by the American Academy of Pediatrics Committee on Infectious Diseases. A month after receiving vaccine at 2, 4, and 12 or 15 months of age, 98% and 100% of the children had > 10 mIU antibodies to hepatitis B surface antigen per milliliter, with gemometric mean titers of 1358 mIU/ml and 3424 mIU/mL, respectively.