Long-term antibody persistence induced by a combined hepatitis A and B vaccine in children and adolescents.

Author(s): Diaz-Mitoma F, Law B, Subramanya A, Hoet B

Affiliation(s): Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada.

Publication date & source: 2008-03-25, Vaccine., 26(14):1759-63. Epub 2008 Feb 4.

Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't

Two cohorts, comprising of subjects aged 1-6 years and 6-15 years were vaccinated with Twinrix according to a 0-, 1- and 6-month schedule. The 1-6 years cohort was followed up for 7.5 years and the 6-15 years cohort for 10 years. At the latest follow-up time point, all subjects were seropositive for anti-HAV antibodies, while 86.5% (32/37) and 95.5% (21/22) had anti-HBs >or= 10 mIU/ml in the 1-6 years and in the 6-15 years cohort. The geometric mean concentrations (GMCs; mIU/ml) were 233 and 680 for anti-HAV antibodies, and 147 and 165 for anti-HBs antibodies, in the 1-6 years and 6-15 years cohorts, respectively. The high persistence of circulating anti-HAV and anti-HBs antibodies in children and adolescents demonstrates the long-term protection offered by Twinrix in these age groups.