Observational Study of Fostamatinib as Second Line Therapy in Adult Patients With Immune Thrombocytopenia (ITP) and Insufficient Response to a Prior Therapy

Inclusion Criteria

• •1. Willing and able to provide written informed consent
• •2. Diagnosis of ITP in adult patients (≥ 18 years of age) with an insufficient response to steroids ± immunoglobulins and requiring a change in therapy
• •3. For Cohort 1, intent to initiate fostamatinib at enrollment as change in therapy
• •4. For Cohort 2, currently undergoing treatment with fostamatinib as second line therapy for at least 12 weeks, with the intent to continue, at the time of enrollment