This is a prospective, controlled, open-label, pharmacokinetic study. This study aims at studying the PK of ledipasvir, sofosbuvir, and GS-331007 metabolite in HCV infected children with hematological malignancy.

In this study, patients in both treatment groups will receive 12 weeks of treatment with a fixed-dose combination tablet containing 45 mg of ledipasvir and 200 mg of sofosbuvir (LDV/SOF) orally, once daily with food.

In this study, patients in both treatment groups will receive 12 weeks of treatment with a fixed-dose combination tablet containing 45 mg of ledipasvir and 200 mg of sofosbuvir (LDV/SOF) orally, once daily with food, as prescribed by the attending physician.

Twelve eligible HCV-infected patients with hematological malignancy and 12 matching HCV control patients without haematological malignancy or co-morbidities will be enrolled in the study.

At baseline, careful history of the recruited patients including demographic characteristics (age, height, weight, and gender), comorbidities, medication history, familial history, social history, blood transfusion history, time on maintenance chemotherapy, and baseline laboratory tests will be documented. The baseline laboratory tests will include renal function tests (serum creatinine), liver function tests (bilirubin, albumin, AST, and ALT), international normalized ratio (INR), alpha fetoprotein (AFP), complete blood count (CBC), degree of liver fibrosis by Fibroscan, and viral load by PCR.

Followup will be done for all participants at baseline, after 12 weeks of treatment, and after 12 weeks from the end of treatment. A Forth visit will be done after 10 days of treatment for the evaluation of the steady state PK parameters of LDV\SOF in those patients.

Inclusion Criteria:

• Children (6 to < 12 years of age and/or weighing 17.5 to < 35 Kg).
• Chronic HCV genotype 4 infection for at least 6 months without cirrhosis (confirmed by Fibroscan).
• Naïve patients to previous anti-HCV treatment.
• Diagnosed with hematological malignancy and on maintenance chemotherapy.

Exclusion Criteria:

• Known hypersensitivity to any of the study medications.

• Ongoing treatment with any interacting medications like carbamazepine, fosphenytoin, phenytoin, oxcarbazepine, phenobarbital, and rifampin.

• History of any comorbid illness that may interfere with the pharmacokinetics of the study drugs or prohibit the compliance with the study protocol such as;

  1. Decompensated liver disease as shown by the presence of ascites, encephalopathy, or a history of variceal hemorrhage.
  2. The ongoing treatment of other types of cancer or blood disorders.
  3. Co-infection with human immunodeficiency virus (HIV), or hepatitis B virus.
  4. Renal dysfunction.
  5. Active infection that is currently producing symptoms.