A new study testing the efficacy of fedratinib in the real world is now open. The multicenter prospective and retrospective observational study will assess the efficacy of the treatment in patients with primary myelofibrosis (MF) or post polycythemia vera or post essential thrombocythemia MF following reimbursement approval by the Italian Medicines Agency (AIFA). 

The study aims to enroll 93 participants, aged 18 years or older who were recently diagnosed or are in follow-up. Both patients who have been exposed to ruxolitinib and those who are ruxolitinib-naïve are eligible. However, those whose disease has transformed to blast phase are not. 

The primary outcome measure is splenic response, defined as a 50% palpatory response, at 6 months.

Fedratinib received reimbursement approval from the AIFA in June 2022. The study sponsored by Gruppo Italiano Malattie EMatologiche dell’Adulto is not yet recruiting participants but is estimated to start in September 2023. The estimated study completion date is September 2025. 

MF is a rare disease characterized by bone marrow scarring due to the production of excess fibrous tissue, which interferes with the normal production of blood cells. It is caused by the activation of the Janus kinase/signal transducer and activator of the transcription (JAK/STAT) signaling pathway, which leads to cell proliferation, inhibition of cell death, and clonal expansion of myeloproliferative tumor cells. Symptoms include anemia, easy bleeding and bruising, fatigue, bone or joint pain, and splenomegaly.

The disease can be primary or idiopathic, occurring in the absence of any other condition or secondary to other conditions such as polycythemia vera, essential thrombocythemia, multiple myeloma, lymphoma, or chronic myeloid leukemia.

Read more about the different types of MF

Fedratinib, sold under the brand name Inrebic®, is a potent oral kinase inhibitor that has high potency for JAK2. It was approved by the US Food and Drug Administration in 2019 for the treatment of adults with intermediate-2 or high-risk MF. In February 2021, the treatment was granted full marketing authorization by the European Medicines Agency.


Real world evidence of fedratinib effectiveness in MF (REALFed). ClinicalTrials.gov. June 1, 2023. Accessed June 6, 2023.