Pharmacokinetics of Two Formulations of Entecavir

Inclusion criteria

• Healthy adult, aged between 20 to 45 years old.
• Physically and mentally healthy subjects as confirmed by an interview, medical history, clinical examination, laboratory tests, chest x-ray and electrocardiogram.

• no particular clinical significance in clinical examination and laboratory tests within two months (60 days) prior to administration of study medication.
• normal or considered not clinically significant by the investigator chest X-ray and Electrocardiogram (ECG) results within six months(180 days)prior to administration of study medication.
• Body weight must be above 50 kg for male and 45 kg for female.
• The normal range of the body mass index should be between 18 and 30; body mass index equals [weight (kg)]/[height (m)]2.
• Laboratory determinations results are within normal range or considered not clinically significant by the investigator, including: Serum Glutamic Oxaloacetic Transaminase (SGOT, same as AST), Serum Glutamic Pyruvic Transaminase (SGPT, same as ALT), albumin, glucose, creatinine, uric acid, cholesterol, Triglycerides (TG), Gamma-Glutamyl-Transpeptidase (γ-GT), alkaline phosphatase, total bilirubin, Blood Urea Nitrogen (BUN), Hepatitis B surface antigen (HBsAg), Anti-Hepatitis C virus (HCV) and Anti-Human Immunodeficiency Virus (HIV) test.
• Hematology test results are within normal range or considered not clinically significant by the investigator, including: hemoglobin, hematocrit, White Blood Cell (WBC) count, Red Blood Cell (RBC) count, platelet count and WBC count with differential.
• Urinalysis results are within normal range or considered not clinically significant by the investigator, including: glucose, protein, RBC, WBC, epithelial cells, casts and bacteria.
• Female subject who is:

• using adequate contraception since last menstruation and no plan for conception during the study.
• non-lactating.
• has negative pregnancy test (urine) prior to the study.
• Informed consent form signed.

Exclusion criteria

• A history of drug or alcohol abuse during the past 24 weeks.
• Sensitivity to analogous drug.
• A clinically significant illness (such as lactic acidosis or severe hepatomegaly with steatosis) within the past 4 weeks.
• Evidence of any clinical significant renal, cardiovascular, hepatic, hematopoietic, neurological, pulmonary or gastrointestinal pathology within the past 4 weeks.
• Planned vaccination during the time course of the study.
• Participation of any clinical investigation during the last 60 days.
• Regular use of any medication during the last 4 weeks.
• Single use of any medication during the last 2 weeks.
• Blood donation of more than 250 mL within the past 12 weeks.
• Employees and their families of sponsor and/or Contract Research Organization (CRO) company.
• Individuals are judged by the investigator or co-investigator to be undesirable as subjects.