Hepatitis B Virus Antibody Booster Program for the Production of Hepatitis B Immune Globulin (HBIG)

Inclusion Criteria * Age 20-55 years. * Naïve or previously hepatitis B-vaccinated males or females. * Normal and healthy as determined by medical history, physical exam, vital signs and clinical laboratory tests * Subject must meet all required/recommended subject suitability criteria that pertain to normal source plasma donors with the following exception: * Subjects who previously tested positive for HBsAg may be accepted into the anti- HBs program provided they now test negative and meet all other normal donor suitability criteria. * Written informed consent. Exclusion Criteria: * Subjects who have received a hepatitis B vaccination in the previous six months. * History of hypersensitivity to yeast or any components of the Engerix-B® vaccine * History of hypersensitivity to any hepatitis B-containing vaccine. * Use of any investigational product within the past 30 days or during the course of the study. * Use of steroids or immunosuppressives during the study period. * Received immunosuppressive therapy (including systemic steroids) within 30 days before study entry * Subjects who have received cytotoxic therapy (in the previous 5 years prior to study entry) * Received parenteral immune globulin products or blood products within 3 months before study entry with the following exceptions: * RhoGAM (or equivalent anti-D immune globulin) within 6 weeks before study entry; * Pertussis immune globulin: no exclusion * Received parenteral immune globulin products or blood products (within 3 months before study entry) * Past, present, or suspected IV drug use * Positive HIV, HBV\* or HCV test result (\*except as described above in Inclusion Criteria) * Autoimmune disease (such as, but not limited to demyelinating disease) * Subjects with cancer, heart disease (including hospitalization for myocardial infarction, arrhythmia, syncope, congestive heart failure), uncontrolled hypertension, uncontrolled insulin-dependent diabetes mellitus, seizures, kidney disease * Severely or morbidly obese, or higher obesity classification, which corresponds to BMI of 35 or higher * Pregnancy or lactation.