Effect of fostatinib/fotantinib on refractory ITP

Fostamatinib is an oral small molecule kinase inhibitor that is regarded as an important complementary option in the treatment of chronic immune thrombocytopenia (ITP) overseas. It is especially suitable for refractory patients who have failed to respond to multiple lines of previous treatments. From the perspective of its mechanism of action, fostatinib interferes with the antibody-mediated platelet destruction process by inhibiting the spleen tyrosine kinase (SYK) signaling pathway, which is different from traditional treatment ideas that rely on "suppression of immunity" or "stimulation of platelet production." This mechanism makes it unique in some patients with long-term recurrent exacerbations and unsatisfactory response to glucocorticoids, gamma globulin or TPO receptor agonists.

Overseas research and clinical practice have shown that the efficacy of fostatinib is not “short-term rapid platelet rise”, but rather a gradual improvement in platelet stability. In some patients, platelet counts can be observed to be maintained within a relatively safe range after continued medication, thereby reducing the risk of bleeding and reducing reliance on emergency platelet therapy. For long-term ITP patients, this "stable and sustainable" efficacy is of great significance in clinical management, especially for patients who want to reduce hormone exposure or frequent infusion therapy.

Judging from real-world experience, the positioning of fostatinib in refractoryITP has gradually become clear: it does not replace all existing therapies, but serves as one of the important options after multi-line treatment. Some overseas hematologists have found in practice that fostatinib is more suitable for patients with a longer course of disease and where immune-mediated platelet destruction is the dominant factor. Compared with drugs that simply stimulate bone marrow hematopoiesis, its action path is closer to the immune pathogenesis of ITP, which is also an important reason why it has been repeatedly discussed and recommended in refractory ITP.

Reference materials:https://go.drugbank.com/drugs/DB12010