Hepatitis B Immune Globulin (Human)

INDICATIONS AND USAGE Nabi-HB, Hepatitis B Immune Globulin (Human), is indicated for treatment of acute exposure to blood containing HBsAg, perinatal exposure of infants born to HBsAg-positive mothers, sexual exposure to HBsAg-positive persons and household exposure to persons with acute HBV infec- tion in the following settings: Acute Exposure to Blood Containing HBsAg: Following either parenteral exposure (needlestick, bite, sharps), direct mucous membrane contact (accidental splash), or oral ingestion (pipetting accident), involving HBsAg-positive materials such as blood, plasma, or serum. Perinatal Exposure of Infants Born to HBsAg-positive Mothers: Infants born to mothers positive for HBsAg with or without HBeAg 12 . Sexual Exposure to HBsAg-positive Persons: Sexual partners of HBsAg-positive persons. Household Exposure to Persons with Acute HBV Infection: Infants less than 12 months old whose mother or primary caregiver is positive for HBsAg. Other household contacts with an identifiable blood exposure to the index patient. Nabi-HB is indicated for intramuscular use only.

DOSAGE AND ADMINISTRATION This product is for intramuscular use only. The use of this product by the intravenous route is not indicated. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. It is important to use a separate vial, sterile syringe, and needle for each individual patient, in order to prevent transmission of infectious agents from one person to another. Any vial of Nabi-HB, Hepatitis B Immune Globulin (Human) that has been entered should be used promptly. Do not reuse or save for future use. This product contains no preservative; therefore, partially used vials should be discarded immediately. Hepatitis B Immune Globulin (Human) may be administered at the same time (but at a different site), or up to one month preceding hepatitis B vaccination without impairing the active immune response to hepatitis B vaccine 11 . Acute Exposure to Blood Containing HBsAg Table 2 summarizes prophylaxis for percutaneous (needlestick, bite, sharps), ocular, or mucous membrane exposure to blood according to the source of exposure and vaccination status of the exposed person. For greatest effectiveness, passive prophylaxis with Hepatitis B Immune Globulin (Human) should be given as soon as possible after exposure, as its value after seven days following exposure is unclear 12 . An injection of 0.06 mL/kg of body weight should be administered intramuscularly as soon as possible after exposure and within 24 hours, if possible. Consult the hepatitis B vaccine package insert for dosage information regarding the vaccine. For persons who refuse hepatitis B vaccine or are known non-responders to vaccine, a second dose of Hepatitis B Immune Globulin (Human) should be given one month after the first dose 12 . Table 2 Recommendations for Hepatitis B Prophylaxis Following Percutaneous or Permucosal Exposure 12 * Hepatitis B Immune Globulin (Human) dose of 0.06 mL/kg IM. † See manufacturer’s recommendation for appropriate dose. ‡ Less than 10 mIU/mL anti-HBs by radioimmunoassay, negative by enzyme immunoassay. § Two doses of Hepatitis B Immune Globulin (Human) is preferred if no response after at least four doses of vaccine. Exposed Person Source Unvaccinated Vaccinated HBsAg-positive Hepatitis B Immune Globulin (Human) X1 immediately* Initiate HB vaccine series† Test exposed person for anti-HBs If inadequate antibody ‡ , Hepatitis B Immune Globulin (Human) X 1 immediately plus either HB vaccine booster dose or second dose of Hepatitis B Immune Globulin (Human) one month later § Known Source - High Risk for HBsAg-positive Initiate HB vaccine series Test source for HBsAg. If positive, Hepatitis B Immune Globulin (Human) X 1 Test source for HBsAg only if exposed is vaccine nonresponder; if source is HBsAg-positive, give Hepatitis B Immune Globulin (Human) X 1 immediately plus either HB vaccine booster dose or second dose of Hepatitis B Immune Globulin (Human) one month later § . Known Source - Low Risk for HBsAg-positive Initiate HB vaccine series Nothing required Unknown Source Initiate HB vaccine series Nothing required Prophylaxis of Infants Born to Mothers who are Positive for HBsAg with or without HBeAg Table 3 contains the recommended schedule of hepatitis B prophylaxis for infants born to mothers that are either known to be positive for HBsAg or have not been screened. Infants born to mothers known to be HBsAg-positive should receive 0.5 mL Hepatitis B Immune Globulin (Human) after physiologic stabilization of the infant and preferably within 12 hours of birth. The hepatitis B vaccine series should be initiated simultaneously, if not contraindicated, with the first dose of the vaccine given concurrently with the Hepatitis B Immune Globulin (Human), but at a different site. Subsequent doses of the vaccine should be administered in accordance with the recommendations of the manufacturer. Women admitted for delivery, who were not screened for HBsAg during the prenatal period, should be tested. While test results are pending, the newborn infant should receive hepatitis B vaccine within 12 hours of birth (see manufacturers’ recommendations for dose). If the mother is later found to be HBsAg-positive, the infant should receive 0.5 mL Hepatitis B Immune Globulin (Human) as soon as possible and within seven days of birth; however, the efficacy of Hepatitis B Immune Globulin (Human) administered after 48 hours of age is not known 10,19 . Testing for HBsAg and anti-HBs is recommended at 12-15 months of age. If HBsAg is not detectable and anti-HBs is present, the child has been protected 12 . Table 3 Recommended Schedule of Hepatitis B Immunoprophylaxis to Prevent Perinatal Transmission of Hepatitis B Virus Infection 19 * See manufacturers’ recommendations for appropriate dose. † 0.5 mL administered IM at a site different from that used for the vaccine. ‡ See ACIP recommendation. Age of Infant Administer Infant Born to mother known to be HBsAg-positive Infant born to mother not screened for HBsAg First Vaccination * Birth (within 12 hours) Birth (within 12 hours) Hepatitis B Immune Globulin (Human) † Birth (within 12 hours) If mother is found to be HBsAg-positive, administer dose to infant as soon as possible, not later than 1 week after birth Second Vaccination * 1 month 1-2 months Third Vaccination * 6 months ‡ 6 months ‡ Sexual Exposure to HBsAg-positive Persons All susceptible persons whose sexual partners have acute hepatitis B infection should receive a single dose of Hepatitis B Immune Globulin (Human) (0.06 mL/kg) and should begin the hepatitis B vaccine series, if not contraindicated, within 14 days of the last sexual contact or if sexual contact with the infected person will continue. Administering the vaccine with Hepatitis B Immune Globulin (Human) may improve the efficacy of post exposure treatment. The vaccine has the added advantage of conferring long-lasting protection 19 . Household Exposure to Persons with Acute HBV Infection Prophylaxis of an infant less than 12 months of age with 0.5 mL Hepatitis B Immune Globulin (Human) and hepatitis B vaccine is indicated if the mother or primary caregiver has acute HBV infection. Prophylaxis of other household contacts of persons with acute HBV infection is not indicated unless they had an identifiable blood exposure to the index patient, such as by sharing toothbrushes or razors. Such exposures should be treated like sexual exposures. If the index patient becomes an HBV carrier, all household contacts should receive hepatitis B vaccine 19 .

ADVERSE REACTIONS SECTION Fifty male and female volunteers received Nabi-HB, Hepatitis B Immune Globulin (Human), intramuscularly in pharmacokinetics trials 20 . The number of patients with reactions related to the administration of Nabi-HB included local reactions such as erythema 6 (12%) and ache 2 (4%) at the injection site, as well as systemic reactions such as headache 7 (14%), myalgia 5 (10%), malaise 3 (6%), nausea 2 (4%), and vomiting 1 (2%). The majority (92%) of reactions were reported as mild. The following adverse events were reported in the pharmacokinetics trials and were considered probably related to Nabi-HB: elevated alkaline phosphatase 2 (4%), ecchymosis 1 (2%), joint stiffness 1 (2%), elevated AST 1 (2%), decreased WBC 1 (2%), and elevated creatinine 1 (2%). All adverse events were mild in intensity. There were no serious adverse events. No anaphylactic reactions with Nabi-HB have been reported. However, these reactions, although rare, have been reported following the injection of human immune globulins 23 .

Pharmacokinetics Pharmacokinetics trials 20 of Nabi-HB, Hepatitis B Immune Globulin (Human), given intramuscularly to 50 healthy volunteers demonstrated pharmacokinetic parameters similar to those reported by Scheiermann and Kuwert 21 . The half-life for Nabi-HB was 23.1 ± 5.5 days. The clearance rate was 0.35 ± 0.12 L/day and the volume of distribution was 11.2 ± 3.4 L. Maximum concentration of Nabi-HB was reached in 6.5 ± 4.3 days. The maximum concentration of anti-HBs and the area under the time-concentration curve achieved by Nabi-HB were bioequivalent to that of another licensed Hepatitis B Immune Globulin (Human) when compared in the same pharmacokinetics trial. Comparability of pharmacokinetics between Nabi-HB and a commercially available hepatitis B immunoglobulin indicate that similar efficacy of Nabi-HB should be inferred.