{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T14:34:22Z","timestamp":1793284462405,"version":"4.5.0"},"reference-count":25,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100016288","name":"Kissei","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100016288","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Int J Hematol"],"published-print":{"date-parts":[[2026,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Immune thrombocytopenia (ITP) is an acquired autoimmune disease characterized by increased platelet destruction and thrombocytopenia. Fostamatinib inhibits spleen tyrosine kinase and suppresses platelet destruction. However, clinical evidence of its efficacy in Japanese patients with ITP remains limited.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this study, we retrospectively evaluated the clinical outcomes of fostamatinib, with or without thrombopoietin receptor agonists (TPO-RAs), at a single center in Japan.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The study included 11 patients. At week 1, all 3 evaluable patients (100.0%) achieved platelet count\u2009\u2265\u200930,000\/\u03bcL and a twofold increase from baseline; at week 2, 10 of 11 (90.9%) met the criteria. Ultimately, 10 of 11 (90.9%) patients achieved the criteria at least once within 24\u00a0weeks. All 3 patients using concomitant TPO-RAs (100.0%) achieved the primary endpoint. After fostamatinib initiation, 9 of 11 (81.8%) patients discontinued or reduced their concomitant glucocorticoid (GC) dose. Thrombosis was not observed regardless of concomitant TPO-RA use.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This study demonstrates the real-world effectiveness and safety of fostamatinib in patients with ITP. Platelet count rose soon after fostamatinib initiation, within 1\u20132\u00a0weeks. Fostamatinib may enable reduction or discontinuation of GCs, even in patients with ITP refractory to TPO-RAs.<\/jats:p>\n                    <jats:p>\n                      <jats:italic>Trial registration<\/jats:italic>\n                      : UMIN000057096\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s12185-026-04243-w","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T15:19:40Z","timestamp":1785856780000},"page":"630-639","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Real-world effectiveness of fostamatinib in patients with immune thrombocytopenia: a single-center retrospective study"],"prefix":"10.1007","volume":"124","clinical-trial-number":[{"clinical-trial-number":"umin000057096","registry":"10.18810\/umin-japan"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9996-6459","authenticated-orcid":false,"given":"Katsumichi","family":"Fujimaki","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takaaki","family":"Takeda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kota","family":"Kawabata","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayako","family":"Bouno","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuki","family":"Nakajima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hideaki","family":"Nakajima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,8,4]]},"reference":[{"key":"4243_CR1","doi-asserted-by":"publisher","first-page":"322","DOI":"10.1111\/j.1538-7836.2008.03161.x","volume":"7","author":"M Kuwana","year":"2009","unstructured":"Kuwana M, Okazaki Y, Ikeda Y. Splenic macrophages maintain the anti-platelet autoimmune response via uptake of opsonized platelets in patients with immune thrombocytopenic purpura. J Thromb Haemost. 2009;7:322\u20139.","journal-title":"J Thromb Haemost"},{"key":"4243_CR2","doi-asserted-by":"publisher","first-page":"329","DOI":"10.1007\/s12185-019-02790-z","volume":"111","author":"H Kashiwagi","year":"2019","unstructured":"Kashiwagi H, Kuwana M, Hato T, Takafuta T, Fujimura K, Kurata Y, et al. Reference guide for management of adult immune thrombocytopenia in Japan: 2019 revision. Int J Hematol. 2019;111:329\u201351.","journal-title":"Int J Hematol"},{"key":"4243_CR3","doi-asserted-by":"publisher","first-page":"935","DOI":"10.1007\/s40265-021-01524-y","volume":"81","author":"J Paik","year":"2021","unstructured":"Paik J. Fostamatinib: a review in chronic immune thrombocytopenia. 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KF also received personal fees outside this study from Kissei Pharmaceutical Co., Ltd., Novartis Pharma K.K., Kyowa Kirin Co., Ltd., and Argenx Japan K.K. The other authors declare no conflict of interest.","order":1,"name":"Ethics","label":"Conflict of interest","group":{"name":"EthicsHeading","label":"Declarations"}}]}}