The primary objective of Cohort 1 (adolescents aged 12 to < 18 years, ≥ 35 kg body weight): of this study is to evaluate the safety, tolerability, and antiviral activity (HBV DNA < 20 IU/mL) of tenofovir alafenamide (TAF) 25 mg once daily versus placebo through Week 24 in treatment-naive and treatment-experienced adolescents with chronic hepatitis B (CHB). Cohort 2 (children 2 to < 12 years of age) will consist of 2 parts: Part A and Part B. Intensive pharmacokinetic (PK) data will be collected from all participants in Part A to confirm the dose of TAF in each dose group and the remaining participants will be enrolled into Part B once dose confirmation is achieved. The primary objectives of Part A are to evaluate the steady-state PK of TAF and tenofovir (TFV) and confirm the dose of TAF given once daily in children (with CHB. The primary objective of Part B is to evaluate the safety, efficacy and tolerability of TAF at Week 24 and the antiviral activity (HBV DNA < 20 IU/mL) of TAF at Week 24 in children with CHB.
A Randomized, Double-Blind Evaluation of the Pharmacokinetics, Safety, and Antiviral Efficacy of Tenofovir Alafenamide (TAF) in Children and Adolescent Subjects With Chronic Hepatitis B Virus Infection