Immunogenicity and Safety of GSK Biologicals' HBV-MPL Vaccine and Engerix™-B in Healthy Adults (15-40 Yrs).

Inclusion Criteria:

• Age: between 15 and 40 years old.
• Good physical condition as established by clinical examination and history taking at the time of entry.
• Female participants who are at risk to become pregnant will be on a contraceptive programme if necessary during the study period.
• Written informed consent obtained from the subjects aged between 18 and 40 and from the parents/tutor when the subjects are aged between 15 and 17 years.

Exclusion Criteria:

• Positive titres at screening for anti-HBs antibodies.
• Elevated serum liver enzymes.
• History of significant and persisting hematologic, hepatic, renal, cardiac or respiratory disease.
• Any acute disease at the moment of entry.
• Chronic alcohol consumption.
• Hepatomegaly, right upper quadrant abdominal pain or tenderness.
• Any chronic drug treatment, including any treatment with immunosuppressive drugs, which in the investigator's opinion, precludes inclusion into the study.
• History of allergic disease likely to be stimulated by any component of the vaccine.
• Simultaneous participation in any other clinical trial.
• Previous vaccination with a hepatitis B vaccine.
• Previous vaccination with an MPL containing vaccine.
• Administration of immunoglobulins in the past 6 months and during the whole study period
• Simultaneous vaccination one week before and one week after each dose of the study vaccine