The purpose of this study is to evaluate the efficacy and safety of generic entecavir monotherapy or in combination with adefovir for chronic hepatitis B patients with inadequate response to NUC therapy

Inclusion Criteria:

• Male or female aged 18-65 years;
• Capable of understanding and signing the informed consent. Willing to comply with the study requirements;
• Serum HBsAg positive and ALT<10ULN at study screening;
• Patients have been treated with one nucleoside/nucleotide analogue for more than 6 months and are still on treatment;

Exclusion Criteria:

• History of viral breakthrough or genotypic resistance on previous therapy;
• History of decompensated liver function, or current signs/symptoms of decompensation e.g. ascites, variceal bleeding, encephalopathy or spontaneous peritonitis;
• Patient has a history of hepatocellular carcinoma(HCC) or findings suggestive of possible HCC;
• Other protocol defined exclusion criteria.