Evaluation of the Efficacy of Tenofovir in Chronic Hepatitis B Patients Unresponsive to Lamivudine

Objective: Chronic hepatitis B virus (HBV) infection is a global health problem and persistent viremia is associated with increased morbidity and mortality. The main goal of hepatitis B treatment is to suppress HBV replication permanently and, antiviral resistance is a major problem against viral suppression. Tenofovir is a potent antiviral drug with no reported resistance so far. There are inadequate data regarding response to tenofovir in chronic hepatitis B patients with lamivudine failure in Turkish population. The present study was conducted to evaluate response of tenofovir in patients with lamivudine failure. Materials and Methods: A total of 48 adult patients with chronic hepatitis B, who have received lamivudine for at least 6 months and switched to tenofovir due to lamivudine failure were investigated retrospectively. HBV DNA levels, alanine aminotransferase (ALT) levels and serum creatinine levels were evaluated before and after tenofovir treatment and also hepatitis B e antigen (HBeAg) seroconversion and hepatitis B surface antigen (HBsAg) loss rates were evaluated. Results: Viral suppression rates (HBV DNA < 400 copies/ml) were found to be 89% on the 6th month and 94% on the 12th month of tenofovir treatment. The mean follow-up time was 21.4 months and totally 96% of patients were found to achieve viral suppression with tenofovir. ALT normalization rates were found to be 60% on the first year of treatment with tenofovir and overall ALT normalization rate was 90%. HBeAg seroconversion was detected in 42% of HBe antigen (+) patients after the first year of tenofovir treatment and disappearance of HBsAg was observed in none of the patients. Conclusion: Tenofovir treatment is an effective and well-tolerated therapeutic option in chronic hepatitis B resistant to lamivudine.