TAVALISSE (fostamatinib) is an oral kinase inhibitor specifically designed to target spleen tyrosine kinase (SYK), a key mediator in the pathogenesis of immune thrombocytopenia. By inhibiting SYK, fostamatinib disrupts signal transduction pathways involved in antibody-mediated platelet destruction, thereby increasing platelet counts in affected individuals. The drug is administered orally, with dosing regimens tailored to patient response and tolerability.

Fostamatinib is metabolized to its active form, tamatinib, which exerts the primary pharmacological effect. Clinical studies have demonstrated its efficacy in patients with chronic ITP who have not responded adequately to previous treatments. TAVALISSE may be taken with or without food, and its use requires regular monitoring of blood pressure, liver function, and complete blood counts due to potential adverse effects such as hypertension, hepatotoxicity, diarrhea, and neutropenia. Use in populations other than adults with chronic ITP is not specified in the specification.