An Efficacy and Safety Study of Fedratinib Compared to Best Available Therapy in Subjects With DIPSS-intermediate or High-risk Primary Myelofibrosis, Post-polycythemia Vera Myelofibrosis, or Post-essential Thrombocythemia Myelofibrosis and Previously Treated With Ruxolitinib

Inclusion criteria

• ✓. Subject is at least 18 years of age at the time of signing the informed consent form (ICF)
• ✓. Subject has an Eastern Cooperative Oncology Group (ECOG) Performance Score (PS) of 0, 1 or 2
• ✓. Subject has diagnosis of primary myelofibrosis (PMF) according to the 2016 World Health Organization (WHO) criteria, or diagnosis of post-ET or post-PV myelofibrosis according to the IWG-MRT 2007 criteria, confirmed by the most recent local pathology report
• ✓. Subject has a DIPSS Risk score of Intermediate-2 or High
• ✓. Subject has a measurable splenomegaly during the screening period as demonstrated by spleen volume of ≥ 450 cm3 by MRI or CT-scan and by palpable spleen measuring ≥ 5 cm below the left costal margin
• ✓. Subject has a measurable total symptoms score (≥ 1) as measured by the Myelofibrosis Symptom Assessment Form (MFSAF)
• ✓. Subject has been previously exposed to ruxolitinib, and must meet at least one of the following criteria (a and/or b)
• ✓. Treatment with ruxolitinib for ≥ 3 months with inadequate efficacy response (refractory) defined as \< 10% spleen volume reduction by MRI or \< 30% decrease from baseline in spleen size by palpation or regrowth (relapsed) to these parameters following an initial response