Background/Aims
: We studied to evaluate the virological and biochemical responses to lamivudine and to detect YMDD mutants in patients who received long-term lamivudine therapy. Methods : We conducted a one-year trial of lamivudine in 45 Korean patients with chronic liver disease due to hepatitis B virus. The patients were treated with a single oral average dose of 100 mg of lamivudine every day for 12 months. Results : The suppression of serum HBV DNA was sustained in 77.8% of the patients and the normalization of serum ALT in 80%. The proportions of patients with HBeAg seroconversion were 25%. YMDD mutants were detected in 4 of 8 patients who showed sustained HBV DNA and serum ALT response (n=31) and in 3 of 8 patients who showed HBV DNA or serum ALT breakthrough (n=9). The response to lamivudine therapy in HBeAg-negative patients was excellent. Conclusion : Lamivudine therapy resulted in a significant virological and biochemical improvements and were well tolerated. But, YMDD mutants were detected during lamivudine therapy. (Korean J Hepatol 1999;5:97－104)