BACKGROUND:?It has been demonstrated that only a minority of patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) obtain a sustained response after either interferon (IFN) or nucleos(t)ide analogue monotherapy. Therefore, combination therapy of drugs with synergistic antiviral effects was proposed to have a sustained response in these patients. We compared the effect and safety of lamivudine monotherapy and its combination with IFN including conventional interferon (CON-IFN) and pegylated interferon (PEG-IFN) for HBeAg-negative CHB patients. DATA? SOURCES:?A group of three independent reviewers identified 9 eligible randomized controlled trials through electronic searches (MEDLINE, OVID, EMBASE, the Cochrane Library Clinical Trials Registry, and the Chinese Medical Database), manual searches, and contact with experts. Sustained virological and biochemical responses were defined as primary efficacy measures. We performed quantitative meta-analyses to assess differences between CON-IFN plus lamivudine combination and lamivudine monotherapy groups. RESULTS:?No greater sustained virological and biochemical rates were found in patients receiving CON-IFN/lamivudine combination therapy [29.1% vs. 26.7%, odds ratio (OR)=0.98, 95% confidence interval (CI) 0.65-1.50, P=0.94, and 41.8%vs. 40.3%, OR=1.13, 95% CI 0.78-1.65, P=0.51, respectively], though a reduced YMDD mutation rate was achieved in the combination group [8.39% vs. 30.0%, OR=0.16, 95% CI 0.076-0.33, P