[Clinical efficacy of entecavir therapy and factors associated with treatment response in naive chronic hepatitis B patients].

BACKGROUND/AIMS: Entecavir is a potent and selective guanosine analogue that has demonstrated a significant antiviral efficacy against hepatitis B virus (HBV). The aim of this study was to characterize the response to entecavir and to examine the factors affecting that response.

METHODS

We administered 0.5 mg of entecavir once daily for more than 12 months to 114 naive chronic hepatitis B (CHB) patients. We measured the levels of liver enzymes, serological markers, and serum HBV DNA at 3-month interval.

RESULTS

Normalization of serum alanine aminotransferase levels was observed in 68.5% (76/114), 74.6% (85/114), and 81.6% (62/76) of patients after 6, 12, and 24 months of therapy, respectively. HBV DNA levels of <50 copies/mL (as evaluated by polymerase chain reaction) were observed in 43.9% (50/114), 71.1% (81/114), and 85.5% (65/76) of patients after 6, 12, and 24 months, respectively. Viral breakthrough was not observed. The rates of HBeAg loss and seroconversion were 43.5% (27/62) and 14.5% (9/62), respectively, after 12 months of therapy, and 56.4% (22/39) and 15.4% (6/39) after 24 months. The independent factor associated with PCR negativity was early virologic response (EVR; HBV DNA <2,000 copies/mL after 3 months of therapy, P<0.001). The independent factors predicting HBeAg loss were found to be serum albumin levels (P=0.041) and EVR (P=0.005).

CONCLUSIONS

Entecavir induced excellent biochemical and virologic responses in naive CHB patients. EVR was an independent factor for predicting HBV PCR negativity and HBeAg loss.