Safety and Efficacy of Subcutaneous Hepatitis B Immunoglobulin After Liver Transplantation: An Open Single‐Arm Prospective Study

Life‐long hepatitis B immunoglobulin (HBIG) administration is a main component of prophylactic strategy to prevent hepatitis B virus (HBV) reinfection after liver transplantation (LT). Long‐term effects of HBIG treatment are known only for intravenous (IV) and intramuscular formulations. To evaluate safety and efficacy of self‐administered SC HBIG, 135 LT patients receiving a 48‐week treatment were analyzed. The dose of HBIG was 500 IU or 1000 IU if body weight was <75 kg or ≥75 kg, respectively. Patients were switched from the monthly IV HBIG treatment to weekly SC HBIG 2–3 weeks after the last IV dosage. All patients were able to SC self‐injection after a single training. The treatment was effective in maintaining trough anti‐HBs levels >100 IU/L. No severe drug‐related side effects occurred. Fifteen injection‐site small hematomas and four cases of mild itch occurred. At the end of the study, anti‐HBs median titer was 232 IU/L (115–566 IU/L) and 97.8% of patients had an anti‐HBs level >150 IU/L. Due to high mean level of anti‐HBs titers observed during this study, individualized treatment schedules should be further investigated. In conclusion, SC HBIG for long‐term prophylaxis of post‐LT HBV reinfection resulted safe, well accepted, and effective in maintaining adequate anti‐HBs levels.