Management of Refractory Immune Thrombocytopenia with Fostamatinib: A Case Report

Abstract Background: Immune thrombocytopenia (ITP) is characterized by autoantibodies targeting platelets, resulting in a prolonged reduction in platelet count that can persist for more than a year. Symptoms of thrombocytopenia can range from bleeding to asymptomatic. ITP can be idiopathic or caused by various factors such as pregnancy, autoimmune conditions, medications, and infections. Refractory ITP affects a subset of patients who do not respond to standard treatments or relapse after splenectomy, resulting in a fourfold increase in mortality risk compared to the general population, with 50% of deaths due to bleeding and 50% due to infections. Additional tests may identify underlying causes such as autoimmune disorders or infections. The incidence of ITP in adults is approximately 66 per 1,000,000 annually, with chronic refractory cases occurring at approximately 10 per 1,000,000. Fostamatinib, an oral spleen tyrosine kinase (Syk) inhibitor, offers a treatment option by reducing antibody-mediated platelet destruction. However, it is accompanied by side effects such as diarrhea, hypertension, nausea, elevated liver function tests, and neutropenia. Primary Objective: To assess the effectiveness and challenges of using fostamatinib for the treatment of refractory ITP through a detailed case report. Methods: This is a case report of a 66-year-old female who presented with symptoms, was diagnosed with ITP, and did not respond to treatment such as rituximab, splenectomy, IV immunoglobulin, and dexamethasone. The patient was started on 100 mg of fostamatinib twice daily in a clinical setting. Results: Early detection of refractory ITP is critical due to its life-threatening condition. Management includes fostamatinib which has been proven to be effective when patient platelet levels return to the normal range. Conclusions: This case report highlights the importance of fostamatinib and its slow response in clinically improving the patient’s symptoms and maintaining a normal platelet range with adjunctive therapy with low-dose steroids.