Hetrombopag for Pediatric Patients With Chronic Immune Thrombocytopenia

This is a two-part, double-blind, randomized, placebo-controlled, and open-label Phase III study to investigate the efficacy, safety of Hetrombopag in pediatric patients with previously treated chronic ITP. In Part A, patients will receive Hetrombopag for 8 weeks. After completing Part A, patients will begin Part B, in which they will be randomized to receive Hetrombopag or placebo in a 12 week double-blind, placebo-controlled treatment period, following an open-label 12 week treatment period.

Inclusion criteria

• Age ≥ 6 years old and ≤ 17 years old,both sexes.
• Part A:Confirmed diagnosis of ITP ≥6months; Part B: Confirmed diagnosis of ITP ≥12months;Platelets <30×10^9/L twice in a row,and platelets <30×10^9/L before taking the medicine.
• Subjects who are refractory or have relapsed after at least one prior ITP therapy.
• Birth control during and 28 days after the trial.
• Written informed consent must be obtained from the patient's guardian and accompanying informed assent from the patient (for children over 8 years old).

Exclusion criteria

• No evidence of other causes of thrombocytopenia.
• Diagnosis as Evans or Wiskott-Aldrich comprehensive.
• Patients with any prior history of arterial or venous thrombosis, or diagnosis as thrombophilia.
• Suffering from serious, progressive, uncontrolled kidney, liver, gastrointestinal, endocrine, lung, heart, nervous system, brain, or mental illness.
• ALT, AST, or ALP> 1.5 x upper limit of normal (ULN), DBLI, or Scr > 1.2 x upper limit of normal (ULN).
• Active HIV or HCV-Ab positive,HBsAg positive.
• PT result exceeds normal by more than ±3s, APTT result exceeds normal by more than ±10s
• Participated in clinical trials of other drugs (received experimental drugs) within 3 months prior to medication.
• The inestigators determined that other conditions were inappropriate for participation in this clinical trial.