The aim of interferon therapy in HBeAg negative chronic hepatitis B was to make patients obtain immune control to hepatitis B virus defined as sustained viral response after treatment. However this target could not be get if patients keep HBV DNA positive during interferon treatment and offend relapse after treatment withdraw. In this trail, entecavir will add on patients with HBV DNA load ≥1000copies/ml after 3 months of peginterferon alpha 2a treatment, and the efficacies of the combine treatment will be evaluated by the rate of sustained viral response after 48 weeks of treatment and 24 week follow up.

HBeAg negative patients with HBV DNA load ≥1000copies/ml after 3 months of peginterferon alpha 2a treatment would be randomize enrolled into two groups, in Interventional group, patients will receive entecavir combine with peginterferon alpha 2a treatment for 48 weeks and followed 24 weeks. Patients in control group will be continue treated only by peginterferon alpha 2a for 48 weeks and followed 24 weeks after treatment. Serum HBV DNA load, HBsAg/anti-HBs level, HBeAg/anti-HBe will be tested at enrollment and every 3 months during the treatment course. Parameters of Liver and kidney function, and liver ultrasound examination will be tested with intervals 1-3 months. The efficacies of combined therapy were evaluated by the rate of sustained viral response after 48 weeks treatment and 24 weeks follow up compared with control group.

Inclusion Criteria:

• HBeAg negative patients with HBV DNA load ≥1000copies/ml after 3 months of peginterferon a-2a treatment

Exclusion Criteria:

• Active consumption of alcohol and/or drugs
• Co-infection with human immunodeficiency virus, hepatitis C virus, or hepatitis D virus
• History of autoimmune hepatitis
• Psychiatric disease
• Evidence of neoplastic diseases of the liver