RESUMO
BACKGROUND/AIMS: The aims of this study were to characterize the treatment response to entecavir and to examine factors affecting that response. METHODS: A total of 77 nucleoside-naive patients with chronic hepatitis B who had received entecavir (0.5 mg daily) for at least 48 weeks were consecutively enrolled between March 2007 and March 2011. The rates of virological response (hepatitis B virus [HBV] DNA < 116 copies/mL), biochemical response (alanine aminotransferase < or = upper limit of normal), hepatitis B e antigen (HBeAg) loss, and seroconversion were retrospectively analyzed. RESULTS: The cumulative rates of virological response at 12, 24, 48, 96, and 144 weeks were 59.7%, 82%, 88.3%, 89.6%, and 93.1%, respectively; biochemical response rates were 51.9%, 74%, 84.4%, 94.8%, and 98.3%, respectively; HBeAg loss rates were 10.5%, 18.4%, 28.9%, 36.8%, and 47.4%, respectively; and HBeAg seroconversion rates were 7.9%, 18.4%, 21.1%, 28.9%, and 39.5%, respectively. In multivariate analysis, independent predictors associated with HBV DNA polymerase chain reaction (PCR) negativity were the absence of HBeAg at baseline (p = 0.006) and early virological response (HBV DNA < 2,000 copies/mL after 12 weeks of therapy; p = 0.027). In univariate analysis, early virological response was an independent factor predicting HBeAg loss (p = 0.001). CONCLUSIONS: Entecavir induced excellent biochemical and virological responses in nucleoside-naive patients with chronic hepatitis B. Early virological response was an independent factor predicting HBV PCR negativity and HBeAg loss, and can be used to predict long-term treatment response to entecavir.