['Attaining hepatitis B e antigen (HBeAg) seroconversion during lamivudine treatment is associated with fewer relapses in HBeAg-positive patients. In HBeAg-negative patients, predictors for post-treatment relapse remain largely unknown. We therefore studied whether end-of-treatment virologic response correlated with relapse after lamivudine treatment.', 'We prospectively analyzed 12 HBeAg-negative patients and 14 HBeAg-positive patients with chronic hepatitis B, who received at least 9 mo of lamivudine treatment and were followed up for 12 mo post-treatment. Relapse of hepatitis B activity was defined by an elevation of serum ALT level above twice the upper limit of normal as well as reappearance of serum HBV DNA by the branched DNA assay or HBeAg during the follow-up period. The serum viral loads during and at the end of treatment were further determined by a quantitative real-time polymerase chain reaction assay.', 'Relapse occurred in 6 (50.0%) HBeAg-negative patients within 12 mo post-treatment. Two relapsers had end-of-treatment serum viral load <1 000 copies/mL, the proportion was not significantly different from that in the 6 non-relapsers (33.3% vs 16.7%; P = 1.00). Hepatitis B virus (HBV) DNA levels did not correlate with post-treatment relapse in HBeAg-positive patients either. However, genotype C patients tended to have a lower relapse rate than genotype B patients (14.3% vs 57.9%, P = 0.08).'] Does end-of-treatment virologic response predict relapse after lamivudine treatment for chronic hepatitis B?