Safety and Efficacy of Ledipasvir/Sofosbuvir Fixed Dose Combination +/- Ribavirin in Adolescents and Children With Chronic HCV-Infection
Safety and Efficacy of Ledipasvir/Sofosbuvir Fixed Dose Combination +/- Ribavirin in Adolescents and Children With Chronic HCV-Infection
The primary objective of the PK Lead-in Phase of the study is to evaluate the steady state
 pharmacokinetics (PK) and confirm the dose of ledipasvir/sofosbuvir (LDV/SOF) fixed dose
 combination (FDC) in hepatitis C virus (HCV)-infected pediatric participants. The PK Lead-in
 Phase will also evaluate the safety, tolerability, and antiviral activity of 10 days of
 dosing of LDV/SOF FDC in HCV-infected pediatric participants.

 The Treatment Phase will be initiated by age cohort after confirmation of age-appropriate
 LDV/SOF FDC dosage levels. Participants from the PK Lead-in Phase will immediately rollover
 into the Treatment Phase with no interruption of study drug administration. The primary
 objective of the Treatment Phase is to evaluate the antiviral efficacy, safety, and
 tolerability of LDV/SOF FDC +/- ribavirin (RBV) for 12 or 24 weeks in pediatric participants
 with HCV.

 During screening, participants will receive placebo to match LDV/SOF FDC to assess ability to
 swallow tablets.
Key Inclusion Criteria:

 -  Consent of parent or legal guardian required

 -  Chronic HCV infection

 -  Screening laboratory values within defined thresholds

 Key Exclusion Criteria:

 -  History of clinically significant illness or any other medical disorder that may
 interfere with individual's treatment, assessment or compliance with the protocol.

 -  Co-infection with HIV, acute hepatitis A virus, or hepatitis B virus

 -  Clinical hepatic decompensation (i.e., ascites, encephalopathy or variceal hemorrhage)

 -  Pregnant or nursing females

 -  Known hypersensitivity to study medication

 -  Use of any prohibited concomitant medications as within 28 days of the Day 1 visit

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