Clinical response to long-term tenofovir monotherapy in Korean chronic hepatitis B patients.

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is a potent nucleotide analogue recommended as first-line monotherapy for chronic hepatitis B (CHB). We investigated the clinical response to TDF monotherapy in Korean CHB patients.

METHODS: A total of 90 CHB patients [55 hepatitis B e antigen (HBeAg)-positive and 35 HBeAg-negative] who received TDF monotherapy for >2year, were enrolled. Quantitative hepatitis B surface antigen (qHBsAg) levels, serum alanine aminotransferase (ALT), HBeAg, anti-HBe and HBV DNA levels were measured during treatment. Virologic response (VR) was defined as undetectable HBV DNA level.

RESULTS: The cumulative incidences of complete virologic response (CVR) were 75.6% and 89.9% at months 12 and 24, respectively. The cumulative CVR rates were significantly higher in HBeAg-negative than HBeAg-positive group (P<0.001). HBeAg loss/seroconversion was observed in 21 (38.2%) out of 55 HBeAg-positive patients. One HBeAg-positive and 1 HBeAg-negative patients (2.2%) achieved HBsAg loss at months 6 and 8 of TDF therapy, respectively. Baseline HBV DNA level and qHBsAg were significant predictive factors for a CVR (P=0.001 and P<0.001, respectively).

CONCLUSIONS: Virologic, serologic, biochemical responses were achieved in both HBeAg-positive and HBeAg-negative patients under 24-month TDF therapy. Monitoring using baseline HBV DNA and qHBsAg levels would be helpful to predict CVR.