A Study to Evaluate the Efficacy and the Change of sAg Levels in Chronic Hepatitis B Patients Receiving Clevudine Treatment Over the Long Period

Inclusion Criteria: 1. Patient is 18 years and older. 2. Patient is documented to be HBsAg positive for \> 6 months and HBV DNA positive. 3. Patient is HBeAg positive or negative. 4. Patient has ALT levels ≥ 80 IU/L 5. Patient who is able to give written informed consent prior to study start and to comply with the study requirements. Exclusion Criteria: 1. Patient is currently receiving antiviral, immunomodulatory, cytotoxic or corticosteroid therapy. 2. Patients previously treated with interferon within the previous 3 months. 3. Patients previously treated with clevudine, lamivudine, adefovir, entecavir, telbivudine or any other investigational nucleoside for HBV infection. 4. Patient is coinfected with HCV, HDV or HIV. 5. Patient is pregnant or breast-feeding. 6. Patient has a clinically relevant history of abuse of alcohol or drugs. 7. Patient has a significant immunocompromised, gastrointestinal, renal, hematological, psychiatric, bronchopulmonary, biliary diseases excluding asymptomatic GB stone, neurological, cardiac, oncologic(except HCC)or allergic disease or medical illness that in the investigator's opinion might interfere with therapy. 8. Patient has creatinine clearance less than 60mL/min as estimated by the following formula: (140-age in years) (body weight \[kg\])/(72) (serum creatinine \[mg/dL\]) \[Note: multiply estimates by 0.85 for women\]