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.