Study of Entecavir in Patients With Chronic Hepatitis B Virus (HBV) Infection

Inclusion Criteria: * Chronic HBV infection * HBV nucleoside/tide-naive or -experienced * Patients who, in opinion of investigator, are appropriate for initiating or modifying their HBV therapy and who are appropriate for a treatment regimen comprised of nucleoside/tide monotherapy with either ETV or another standard of care HBV nucleoside/tide analogue * Age 16 and older or minimum age required in a given country Exclusion Criteria: * Women who are pregnant or breastfeeding * Patients who, in the opinion of the investigator, are expected to have a liver transplant-free survival of less than one year * Patients who, in the opinion of the investigator, are virologically controlled on their current treatment regimen and clinically responding to treatment, unless the regimen needs to be modified for medication intolerance * Coinfection with HIV * History of malignant neoplasm(s), including hepatocellular carcinoma (HCC) and carcinoma in situ (CIS), but excluding non-melanoma skin cancers * Patients with chronic renal insufficiency, defined as a creatinine clearance \< 50 ml/min who do not have either of the following means of dose reducing ETV: i. an approved country-specific ETV label which includes the extended interval ETV dose modification method and/or ii. an approved country specific label for the ETV oral solution AND access to the oral solution * History of dysplastic liver nodules * Known history of allergy to nucleoside/tide analogues * Prior or current treatment with entecavir * An investigator proposed study regimen which will include only interferon-alfa * An investigator proposed study regimen of combination (two or more) HBV nucleoside/tide analogues