Publication of data from phase II study of fostamatinib for the treatment of warm antibody autoimmune hemolytic anemia in the American Journal of Hematology.- Rigel Pharma
Rigel Pharmaceuticals, Inc. announced the publication of data in the American Journal of Hematology from the open label, multicenter, Phase II clinical study of fostamatinib in adults with warm antibody autoimmune hemolytic anemia (wAIHA) who had failed at least one prior treatment.
The published data demonstrate that fostamatinib, an oral spleen tyrosine kinase (SYK) inhibitor, rapidly and durably increased hemoglobin (Hgb) levels, with clinically meaningful Hgb responses observed in nearly half of the patients, and a safety and tolerability profile consistent with the existing fostamatinib safety database of patients across multiple disease programs studied. The publication, entitled "Fostamatinib for the treatment of warm antibody autoimmune hemolytic anemia: Phase II, multicenter, open-label study", is available on the journal website, https://onlinelibrary.wiley.com/doi/10.1002/ajh.26508.
The Phase II study evaluated the response to fostamatinib at 150 mg BID (twice daily) in adult patients with wAIHA and active hemolysis with Hgb of less than 10 g/dL who had failed at least one prior treatment. The primary endpoint was Hgb greater than 10 g/dL with an increase of ?2 g/dL from baseline by Week 24 without rescue therapy or red blood cell transfusion. The study demonstrated that 46% (11/24) of patients achieved the primary endpoint, with 1 late responder at week 30 (total of 12 responders [50%]). Increases in median Hgb were detected at Week 2 and sustained over time.
The most common adverse events (AEs) were diarrhea (42%), fatigue (42%), hypertension (27%), dizziness (27%), and insomnia (23%). AEs were manageable and consistent with the fostamatinib safety database of over 3,900 patients across multiple diseases (rheumatoid arthritis, B-cell lymphoma, COVID-19, and immune thrombocytopenia (ITP)). No new safety signals were detected.
Fostamatinib is currently being evaluated in a Phase III randomized, double-blind, placebo-controlled clinical study in 90 patients with wAIHA who have failed at least one prior treatment. The study will evaluate the efficacy of fostamatinib versus placebo in achieving a durable hemoglobin response, defined as a hemoglobin level ? 10 g/dL, with an increase from baseline and durability measure in hemoglobin level of ? 2 g/dL, with the response not being attributed to rescue therapy, on 3 consecutive available visits during the 24-week treatment period. Secondary endpoints include other measures of hemoglobin response, use of rescue medication and safety.
See- "Fostamatinib for the treatment of warm antibody autoimmune hemolytic anemia: Phase II, multicenter, open-label study";David J. Kuter, Kerry A. Rogers, Michael A. Boxer, Michael Choi, Richy Agajanian, et al., .American Journal of Hematology. First published: 18 February 2022.