Evaluation of Anti-HBs Serum Levels and Pharmacokinetic Profile After Intravenous Administration of Niuliva, a New Hepatitis B Immunoglobulin, Following Liver Transplantation

PURPOSE: We assessed whether trough anti-hepatitis B surface antigen (HBs) serum levels considered to be protective (>100 IU/L) were maintained in liver transplanted patients after 6 months of uninterrupted treatment with Niuliva, a new intravenous HBIg. METHODS: Twenty patients, aged 18-70 years, who had undergone liver transplantation due to HBV-related liver disease at least 1 year before inclusion were enrolled in a prospective, open-label, uncontrolled, multicenter clinical study. A fixed monthly dose of 5,000 IU of study medication was administered intravenously for 6 months. RESULTS: After the second infusion, all mean values of anti-HBs and 95% CIs were above the limit of 100 IU/L considered to be protective. The percentages of success ranged between 95% (95% CI 75.1%-99.9%) and 100% (95% CI 86.1%-100%). Mean values and 95% CI of in vivo recovery of anti-HBs at 15-30 minutes after each infusion showed overlaps between all intervals, which indicated that significant differences were not present in the recovery of post infusion anti-HBs in vivo. There were no recurrences of HBV infection during the study. There were no seroconversions in patients previously negative to hepatitis C virus or HIV. No serious adverse events related to the study medication were observed. CONCLUSIONS: Serum levels of anti-HBs after using Niuliva in patients who had undergone liver transplantation were protective in 95%-100% of cases after the study period. This new HBIg showed the expected pharmacokinetic profile and was well tolerated and safe.