A new intravenous preparation of hepatitis B immune globulin (HBIG) will be compared to the currently marketed intramuscular product. Both drugs will be infused intravenously in a double blinded crossover design to determine the pharmacokinetic elimination of the anti-HBs activity from patient serum. This data will be evaluated to determine the appropriate dosing of the new product for use in hepatitis B liver transplant recipients.