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

Abstract

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.