Lusutrombopag in the Treatment of Immune Thrombocytopenia (ITP)

Inclusion criteria

• . Males and females ≥18 years of age
• . Subjects\>60 years must have had a diagnostic bone marrow aspiration in the last 3 years or responded to treatment (platelet count ≥50 x 10\^9/L)
• . Participants diagnosed with primary persistent/chronic ITP (greater than or equal to 3 months duration) and an average of two platelet count less than 30 x 10\^9/L. Conditions which may cause thrombocytopenia other than ITP should be ruled out, including but not limited to systemic lupus erythematosus (SLE)，aplastic anemia (AA), and myelodysplastic syndromes (MDS)
• . Relapsed persistent or chronic ITP status, with or without prior splenectomy. Participants who previously received one or more ITP therapies
• . Subjects receiving rescue therapy (including but not limited to corticosteroids, immunoglobulins and immunosuppressant) must have completed these therapies for at least 1 week or failed within 1 week prior to dosing on the first day (Visit 1)
• . Subjects receiving stable dosages of cyclosporine A, mycophenolate mofetil, azathioprine, or danazol are allowed, but must be receiving a dose that has been stable for at least 4 weeks prior to dosing on the first day (Visit 1)
• . Subjects receiving Chinese herbal medicine must be stopped 1 weeks prior to dosing on the first day (Visit 1), and Chinese herbal medicine is not allowed during the study
• . Subjects receiving steroid therapy must be on a stable dose for at least 2 weeks prior to screening (same milligram amount ± 10%； and ≤20 mg of equivalent dose of prednisone)