Backgroud/Aims: Lamivudine is an effective, safe therapeutic agent for the treatment of chronic hepatitis B. The aim of this study was to investigate whether early suppression of the viral load predicts HBeAg loss within 1 year during lamivudine therapy. Methods: This prospective study encompassed 74 patients (mean age: 37.1 years, male/female: 51/23) who were positive HBeAg, their AST or ALT levels were ≥2 times the upper limit of normal and their HBV DNA was ≥105 copies/mL. The patients received lamivudine 100 mg for 12 months with monitoring their HBV DNA, AST, ALT, HBeAg and anti-HBe, and all these tests were performed at pretreatment and 1, 3, 6, 9 and 12 months after treatment. The serum HBV DNA was measured by HBV branched DNA assay. Results: HBeAg loss was observed in 12 patients (16.2%), and 9 patients achieved anti-HBe seroconversion during up to 1 year of lamivudine therapy. The mean time to HBeAg loss was 5.6 months (range: 1-12 months). The posttreatment HBV DNA (<2,000 copies/mL) after 3 month (P=0.008) and 6 month (P=0.012)) were significant predictors of HBeAg loss after 1 year of lamivudine treatment on univariate analysis. Pretreatment HBV DNA, AST/ALT, gender, age and liver cirrhosis had no impact on HBeAg loss. The six-month posttreatment HBV DNA level <2,000 copies/mL was a significant predictor of HBeAg loss on multivariate analysis (P=0.008, odds ratio=0.108). Conclusion: We suggest that an HBV DNA level <2,000 copies/mL at 6 month after lamivudine therapy is the most important predictor of HBeAg loss during up to 1 year of lamivudine therapy. (Korean J Hepatol 2007;13:513-520)
