Zanubrutinib for Immune Thrombocytopenia Treatment

Inclusion Criteria: * Age 18 and above, male or female； * Conform to the diagnostic criteria of immune Thrombocytopenia (ITP)； * Diagnosis of ITP\>3 months； * Primary ITP with a platelet count of \<30 X 109/L prior to inclusion with failure to achieve response or relapse after corticosteroid therapy, and at least one second-line therapy including rituximab \>12 weeks ago and/or TPO-RAs. * Liver and kidney function, such as ALT, AST, BUN, SCR \< 1.5 × upper limit of normal value, passing physical examination; * ECOG physical state score ≤ 2 points； * Cardiac function of the New York Society of Cardiac Function ≤ 2； * Signed and dated written informed consent. Exclusion Criteria: * Uncontrollable primary diseases of important organs, such as malignant tumors, liver failure, heart failure, renal failure and other diseases; * HIV positive; * Accompanied by uncontrollable active infection, including hepatitis B, hepatitis C, cytomegalovirus, EB virus and syphilis positive; * Accompanied by extensive and severe bleeding, such as hemoptysis, upper gastrointestinal hemorrhage, intracranial hemorrhage, etc.; * At present, there are heart diseases, arrhythmias that need treatment or hypertension that researchers judge is poorly controlled; * Patients with thrombotic diseases such as pulmonary embolism, thrombosis and atherosclerosis; * Those who have received allogeneic stem cell transplantation or organ transplantation in the past; * Patients with mental disorders who cannot normally obtain informed consent and conduct trials and follow-up; * Patients whose toxic symptoms caused by pre-trial treatment have not disappeared; * Other serious diseases that may limit the subject's participation in this test (such as diabetes; Severe cardiac insufficiency; Myocardial obstruction or unstable arrhythmia or unstable angina pectoris in recent 6 months; Gastric ulcer, etc.); * Patients with septicemia or other irregular severe bleeding; * Patients taking antiplatelet drugs at the same time; * Pregnant women, suspected pregnancies (positive pregnancy test for human chorionic gonadotropin in urine at screening) and lactating patients.