Dataset from To Evaluate Immune Response to a Hepatitis B Vaccine (Engerix™-B ) Challenge Dose in Healthy Subjects Who Received GSK Biologicals' Hepatitis B Vaccine (Engerix™-B ) Approximately 20 Years Ago as Primary Vaccination at 0, 1, 2 and 12 Months.

The current study will evaluate immunological memory to hepatitis B antigen in subjects who received primary neonatal vaccination of hepatitis B vaccine (Engerix™-B ), 20 years ago in the primary study and who have anti-HBs antibody concentrations < pre-defined cut-off values at the previous long-term time point. All participating subjects will receive a challenge dose of hepatitis B vaccine. Subjects will be aged approximately 20-21 years at the time of this study. No new subjects will be recruited in this long-term follow-up study. Blood sampling will be done one month after the administration of the challenge dose. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.