Efficacy, safety, and pharmacokinetics of intramuscular hepatitis B immune globulin, Igantibe® , for the prophylaxis of viral B hepatitis after liver transplantation

Abstract Background Long-term prophylaxis of hepatitis B virus (HBV) positive liver transplanted subjects with intravenous hepatitis B immunoglobulin (HBIG) is effective, however use of intramuscular HBIG could be as effective with fewer adverse events and lower cost. Aim We conducted a prospective, non-randomized, clinical study to assess the efficacy and safety of HBIG from Grifols, Igantibe® , for the prophylaxis of HBV reactivation. Methods Eighteen adult patients submitted to liver transplantation for HBV-related disease more than 18 months earlier were treated with doses of 2000 I.U. intramuscular Igantibe® every 14 days for 6 months. Results Mean trough serum HBsAb IgG titers from months 4 to 6 (primary efficacy variable) were protective (≥150 I.U./L) at each time point. Individual measurements were also protective throughout the study. HBV replication remained negative for all available subjects until study completion. Pharmacokinetic analysis showed a half-life of 27 days and extensive exposure to the study drug. Safety and tolerability of intramuscular Igantibe® were good, with only one adverse event. Conclusion Standard-dose intramuscular Igantibe® administration proved efficacious in post-liver transplantation prophylaxis by attaining protective levels for up to 6 months, was safe and well tolerated. Pharmacokinetic analysis revealed a long half-life and extensive exposure.