for people ages 2-17 (full criteria)
at San Francisco, California and other locations
study started
estimated completion
Principal Investigator
by Philip Rosenthal



The primary objective of Cohort 1 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 (aged 12 to < 18 years) with chronic hepatitis B (CHB). Cohort 2 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 (aged 2 to < 12 years) with CHB. The primary objective of Part B is to evaluate the safety and tolerability of TAF at Week 48 and the antiviral activity (HBV DNA < 20 IU/mL) of TAF at Week 24 in children (aged 2 to < 12 years) with CHB.

Official Title

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


Chronic Hepatitis B CHB HBV Hepatitis A Hepatitis B Hepatitis B, Chronic Virus Diseases Herpesviridae Infections Hepatitis Hepatitis, Chronic TAF Open-Label TAF


You can join if…

Open to people ages 2-17

  • Males and non-pregnant, non-lactating females
  • Weight at screening as follows:
  • Cohort 1 = ≥ 35 kg (≥ 77 lbs)
  • Cohort 2 Group 1 = ≥ 25 kg (≥ 55 lbs)
  • Cohort 2 Group 2 = ≥ 17 kg to < 25 kg (≥ 37 lbs to <55 lbs)
  • Cohort 2 Group 3 = < 17 kg (< 37 lbs)
  • Willing and able to provide written informed consent/assent (child and parent/legal guardian)
  • Documented evidence of CHB (eg, HBsAg-positive for ≥ 6 months)
  • Treatment-naive or treatment-experienced will be eligible for enrollment.
  • Estimated creatinine clearance (CLCr) ≥ 80 mL/min/1.73m2 (using the Schwartz formula)

  • Normal ECG

You CAN'T join if...

  • Females who are breastfeeding
  • Males and females of reproductive potential who are unwilling to use an "effective", protocol-specified method(s) of contraception during the study.
  • Coinfection with hepatitis C virus (HCV), HIV, or hepatitis D virus (HDV)
  • Evidence of hepatocellular carcinoma (Note: if screening alpha-fetoprotein (AFP) is < 50 ng/mL no imaging study is needed; however, if the screening AFP is > 50 ng/mL an imaging study is required)
  • Any history of, or current evidence of, clinical hepatic decompensation
  • Abnormal hematological and biochemical parameters
  • Chronic liver disease of non-HBV etiology (e.g., hemochromatosis, alpha-1 antitrypsin deficiency, cholangitis)
  • Received solid organ or bone marrow transplant
  • Currently receiving therapy with immunomodulators (eg, corticosteroids), or immunosuppressants
  • Significant renal, cardiovascular, pulmonary, or neurological disease in the opinion of the Investigator
  • Malignancy within the 5 years prior to screening. Individuals under evaluation for possible malignancy are not eligible.
  • Current alcohol or substance abuse judged by the investigator to potentially interfere with subject compliance.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.


  • University of California, San Francisco (UCSF) accepting new patients
    San Francisco California 94158 United States
  • Children's Hospital of Los Angeles accepting new patients
    Los Angeles California 90027 United States

Lead Scientist at UCSF


accepting new patients
Start Date
Completion Date
Gilead Sciences
Phase 2
Study Type
Last Updated