Utilization and Efficacy of Tenofovir DF in Adolescents With Chronic Hepatitis B Virus Infection

Key Inclusion Criteria: 1. 12 to \<16 years of age 2. Documented chronic hepatitis B virus (HBV) infection 3. Weight ≥ 35 kg 4. Able to swallow oral tablets 5. Negative pregnancy test for females of childbearing potential 6. Adequate kidney (renal) function 7. Parent or legal guardian of potential study subjects able to provide written informed consent Key Exclusion Criteria: 1. Previously received tenofovir DF 2. Sexually-active males or females of reproductive potential who are not willing to use an effective method of contraception during the study 3. Females who are pregnant or breastfeeding, or females who wish to become pregnant during the course of the study 4. Known hypersensitivity to tenofovir DF, the metabolites or formulation excipients 5. Any condition (including alcohol or substance abuse) or prior therapy that, in the opinion of the Investigator, would make the subject unsuitable for the study or unable to comply with treatment requirements Note: Other protocol defined Inclusion/Exclusion criteria may apply