[Novel second-line treatments for immune thrombocytopenia]

Immune thrombocytopenia (ITP) is a thrombocytopenic disorder in which anti-platelet antibodies accelerate platelet destruction and impair platelet production. Treatment consists of first-line steroids, followed by second-line therapy if the patient is unresponsive or intolerant to steroids. Thrombopoietin receptor agonists, rituximab, and splenectomy have been the main second-line options. However, the Syk inhibitor fostamatinib and the FcRn inhibitor efgartigimod, two novel agents that are expected to improve platelet counts through a new mechanism of action, have recently been added as second-line treatment options in Japan as well. Many new therapeutic agents for ITP such as BTK inhibitors, BAFF receptor inhibitors, and anti-CD38 antibody agents are also under development. It is hoped that these novel treatment options with different effects will improve the management of ITP in the future.