Individual prediction model for lamivudine treatment response in hepatitis B virus e antigen-positive chronic hepatitis B patients.

Background and Aims Although prolonged lamivudine ( LAM) therapy is associated with the emergence of LAM-resistant mutations, it is still a commonly used therapy in many Asian countries because of its established long-term safety and low cost. The aim of our study was to assess the predictors of long-term LAM treatment response and to establish an individual prediction model ( IPM) for hepatitis B virus e antigen ( HBeAg) seroconversion in HBeAg-positive chronic hepatitis B ( CHB) patients. Methods This was a multicenter analysis of 838 patients treated with LAM between January 1999 and August 2004. Of these, 748 patients were followed up for at least 24 months. Results The median age was 43.0 years (range, 19-79 years) and the mean duration of LAM monotherapy was 34.2 ± 0.7 months. In the multivariate analysis, age (odds ratio [ OR] = 0.974, P < 0.001), baseline alanine aminotransferase level ( OR = 1.001, P = 0.014), and baseline hepatitis B virus DNA level ( OR = 0.749, P < 0.001) were independent factors for HBeAg seroconversion. Based on the predictors, an IPM was established. Patients were classified into high (> 50%), intermediate (30-50%), or low (≤ 30%) response groups based on their probability of HBeAg seroconversion according to the IPM. The cumulative HBeAg seroconversion rate at 6 years for the high, intermediate, and low response groups was 66.0%, 48.5%, and 21.8%, respectively ( P < 0.001). Conclusions An IPM was developed based on predictors of HBeAg seroconversion in HBeAg-positive CHB patients on LAM monotherapy. This model will allow screening of LAM responders prior to the commencement of antiviral treatment. [ABSTRACT FROM AUTHOR]