Real-World Use of Fedratinib for Myelofibrosis Following Prior Ruxolitinib Failure: Patient Characteristics, Treatment Patterns, and Clinical Outcomes

Background: There is a lack of established clinical outcomes for patients with myelofibrosis (MF) receiving fedratinib following ruxolitinib failure. This study examined real-world patient characteristics, treatment patterns, and clinical outcomes of patients with MF treated with fedratinib following ruxolitinib failure in US clinical practice. Patients and Methods: This retrospective patient chart review included adults with a physician-reported diagnosis of MF, who initiated fedratinib after discontinuing ruxolitinib. Descriptive analyses characterized patient characteristics, clinical outcomes, and treatment patterns from MF diagnosis through ruxolitinib and fedratinib treatment. Results: Twenty-four physicians abstracted data for 150 eligible patients. Approximately 55.3% of the patients were male, 68.0% were White, and median age at MF diagnosis was 68 (range, 35-84) years. Median duration of ruxolitinib therapy was 7.6 (range, 0.7-65.5) months. At initiation of fedratinib, 88.0% of patients had palpable spleen and a mean spleen size of 16.0 (standard deviation [SD], 5.9) cm. Spleen size decreased by 19.4% to 13.2 (SD, 7.9) cm at month 3 (P = .0001) and by 53.4% to 7.2 (SD, 7.4) cm at month 6 (P = .01) of fedratinib treatment, respectively. Almost one-third (26.8%) of patients had achieved ≥ 50% spleen reduction by month 6. Mean number of symptoms also decreased significantly at month 3 (P < .0001) and month 6 (P = .01). Conclusion: Fedratinib appears to deliver spleen and symptom benefits in real-world patients with MF previously treated with ruxolitinib.