Platelet Responses After Tapering and Discontinuation of Fostamatinib in Patients with Immune Thrombocytopenia: A Continuation of the Fostasur Study

Background/objectives: Fostamatinib is a spleen tyrosine kinase (SYK) inhibitor approved for the treatment of adult patients with chronic immune thrombocytopenia (ITP). There is little information about dose tapering and sustained remission after discontinuation in ITP. In this retrospective multice...

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Detalles Bibliográficos
Autores: Mingot-Castellano, María Eva, García-Donas, Gloria, Campos-Álvarez, Rosa María, Fernández-Sánchez de Mora, María Carmen, Luis-Navarro, Josefa, Domínguez-Rodríguez, Juan Francisco, Del Mar Nieto-Hernández, María, Sánchez-Bazán, Irene, Yera-Cobo, Maria, Cardesa-Cabrera, Rocio, Jiménez-Gonzalo, Francisco José, Caparrós-Miranda, Isabel, Entrena-Ureña, Laura, Herrera, Sergio Jurado, Fernández Jiménez, Dolores, Díaz-Canales, Dana, Moreno-Carrasco, Gloria, Calderón-Cabrera, Cristina, Nuñez-Vázquez, Ramiro, Pedrote, Begoña, Jiménez Bárcenas, Reyes
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/387123
Acceso en línea:http://hdl.handle.net/10261/387123
https://api.elsevier.com/content/abstract/scopus_id/85208501754
Access Level:acceso abierto
Palabra clave:ITP
SYK
SYK inhibitor
Diarrhea
Fostamatinib
Hemorrhage
Idiopathic
Purpura
Remission
Sustained response
Tapering
Thrombocytopenia
Thrombocytopenic
Thrombopoietin analogs
Descripción
Sumario:Background/objectives: Fostamatinib is a spleen tyrosine kinase (SYK) inhibitor approved for the treatment of adult patients with chronic immune thrombocytopenia (ITP). There is little information about dose tapering and sustained remission after discontinuation in ITP. In this retrospective multicenter study, we evaluated efficacy and safety of fostamatinib in adult patients with ITP before, during, and after tapering/discontinuation (T/D). Methods: T/D was performed on subjects who achieved complete platelet response (CR) with progressive, conditional dose reduction every four weeks. Results: Sixty-one patients were included from 14 reference centers between October 2021 and May 2023. In subjects that completed T/D (n = 9), the median time from treatment initiation to response was 21 days (IQR: 7.5-42), median time from treatment initiation to CR was 28 days (IQR: 28-42), median time from treatment initiation to the start of tapering was 116 days (IQR: 42-140), and duration of tapering was 112.5 days (IQR: 94.5-191). The median platelet count was 232 × 109/L (IQR: 152-345 × 109/L) at tapering and 190 × 109/L (IQR: 142.5-316.5 × 109/L) at discontinuation. With a median follow-up since discontinuation of 263 days (IQR: 247-313 days), only two patients have relapsed (at 63 and 73 days). Fostamatinib was restarted, achieving a new CR. Platelet counts higher than 100 × 109/L in week 12 were the only positive predictive factors for successful tapering and discontinuation. Conclusions: Sustained response in patient with ITP treated with fostamatinib could be developed. The prognostic factors and recommended scheme of tapering still have to be evaluated.