Abstract: Objective We conducted a pilot clinical trial to observe the efficacy of lamivudine in the treatment of hepatitis B patients with liver failure. Methods A total of one hundred and eighty-two patients with liver failure caused by hepatitis B were divided into group A（acute-or subacute-on chronic，n=90）and group B（chronic，n=92）. Lamivudine were given for patients in subgroup A2（n=50）and B2（n=51），while patients in subgroup A1（n=40）and B1（n=41）didn’t received lamivudine. Patients in every groups were treated with supporting and matrine therapy. Results After a mean period of 1.5 month treatment，23 patients（57.5%）in subgroup A1 and 16 patients （32.0%，P<0.05）in subgroup A2 died，whereas after a mean period of 2.5 month treatment，22 patients（53.7%）in subgroup B1 and 24（47.1%，P>0.05）in subgroup B2 died；lamivudine therapy improved ALT normalization both in group A and group B；at the end of 6-mon follow up，80% of patients in subgroup A2 and subgroup B2 were with serum HBV DNA negative，while all patients in subgroup A1 and subgroup B1 were with serum HBV DNA positive.Conclusion Lamivudine can improve the survival of patients with acute- or subacute-on chronic hepatitis b-induced liver failure.

Key words: Hepatitis B, Hepatic failure, Lamivudine, Efficacy