Immunogenicity and Reactogenicity of MPL Adjuvanted Recombinant Hepatitis B- Vaccine and Engerix™-B in Adult Non-Responders

Inclusion Criteria: * Age: older than 18 years of age. * Documented non-responders 2 to 5 months after having received 4 doses of a hepatitis B vaccine * 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 Exclusion Criteria: * Positive at screening for anti-HBV 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 an MPL containing vaccine. * Administration of immunoglobulins 6 months before and during the whole study period * Vaccination one month before and one month after each dose of the study vaccine