Low-dose Rituximab Regimens in Chinese Adult Patients With Immune Thrombocytopenia

Inclusion Criteria: * Age 18-60 years old; * Diagnosis of primary immune thrombocytopenia according to the guidelines of American Society of Hematology for at least 3 months before inclusion; * Platelet count \<30×109/L (measured at least twice during the screening, with at least a 1-week interval); * Failed or dependent on or relapsed after previous treatment with glucocorticoid; * If on glucocorticoid maintenance therapy, dose ≤0.5 mg/kg prednisone or equivalent and stabilised for at least 4 weeks; * Drugs such as azathioprine, danazol, cyclosporine A, tacrolimus, and sirolimus stopped for at least 4 weeks; * Splenectomy more than 6 months previously; * Previous rescue therapy of ITP (including methylprednisolone, platelet transfusion and IVIG) completed at least 2 weeks before the first administration; * Liver and kidney function (including alanine aminotransferase, aspartate aminotransferase, total bilirubin, serum creatine, urea nitrogen, etc.) less than 1.5 times the upper limit of normal value; * Eastern Cooperative Oncology Group performance status ≤2; * Cardiac function classification (New York Heart Association) ≤2; * Understand the research procedure and voluntarily sign a written informed consent form. Exclusion Criteria: * Patients with secondary thrombocytopenia (including myelodysplastic syndrome, aplastic anemia, common variant immunodeficiency disease, hereditary thrombocytopenia, drug-induced thrombocytopenia, pseudothrombocytopenia, connective tissue dis…