Tenofovir therapy for lamivudine resistance following liver transplantation

BACKGROUND: Resistant hepatitis B virus (HBV) strains develop in 30% of liver transplant recipients treated with lamivudine within 2 years from the time of transplantation. OBJECTIVE: To assess safety and outcomes of tenofovir salvage therapy for patients with lamivudine resistance in a retrospective cohort of liver-transplanted patients. METHODS: Medical records were retrospectively evaluated for patients who received tenofovir. Data collected included demographics, HBV serologic information prior to and during tenofovir therapy, drug-related complications, and creatinine clearance. Criteria for lamivudine resistance included elevation of liver chemistries along with reappearance of hepatitis B surface antigen, hepatitis Be antigen, and/or HBV DNA. RESULTS: Sixteen patients showed resistance to lamivudine at 10-85 months (median 26) following liver transplantation. Tenofovir 300 mg/day orally was added in 8 patients 1-66 months after the development of viral lamivudine resistance and continued for 14-26 months (median 19.3). All 8 patients experienced HBV DNA viral suppression, with 7 currently nondetectable. No adverse events were reported, and creatinine clearance was not impaired. CONCLUSIONS: Our results suggest that tenofovir safely and markedly decreases replication of lamivudine-resistant HBV variants after liver transplantation and is another potential option for the treatment of HBV lamivudine resistance.