The Food and Drug Administration has approved fedratinib (Inrebic), an oral JAK2/FLT3 inhibitor, to treat myelofibrosis.
Fedratinib is approved to treat adults with intermediate-2 or high-risk primary or secondary (post–polycythemia vera or post–essential thrombocythemia) myelofibrosis.
The prescribing information for fedratinib includes a boxed warning detailing the risk of serious and fatal encephalopathy, including Wernicke’s.
The encephalopathy risk prompted Sanofi to stop developing fedratinib in 2013. The FDA placed a clinical hold on all trials of fedratinib after potential cases of Wernicke’s encephalopathy were observed in eight patients.
The FDA lifted the clinical hold in 2017, and Celgene Corporation decided to develop fedratinib when the company acquired Impact Biomedicines in 2018.
In the phase 3 JAKARTA trial, fedratinib significantly reduced splenomegaly and symptom burden in patients with primary or secondary myelofibrosis (JAMA Oncol. 2015 Aug;1[5]:643-51). In the phase 2 JAKARTA2 trial, fedratinib produced responses in myelofibrosis patients previously treated with ruxolitinib (Lancet Haematol. 2017 Jul;4[7]:e317-e324).
Fedratinib received orphan drug designation from the FDA, and the application for fedratinib received priority review.
The FDA granted approval of fedratinib to Impact Biomedicines, a wholly owned subsidiary of Celgene.