AIM: Assess real-world fedratinib (FEDR) treatment patterns and clinical outcomes in patients with primary or secondary myelofibrosis following discontinuation of ruxolitinib (RUX). PATIENTS & METHODS: This study was a retrospective, noninterventional medical record review of patients in Canada, Germany, and the United Kingdom (UK). A total of 70 physicians (primarily hematologist-oncologists [78.6%]) provided data for 196 eligible patients. RESULTS: Patients were mostly male (62.8%) with primary myelofibrosis (76.5%) and initiated FEDR at a mean age of 67.7 years. Median treatment duration was 11.5 months (median follow-up, 13.8 months), and nearly half (49.5%) of patients initiated FEDR at the label-indicated dose of 400 mg daily. Six months post-initiation, 77.7% and 66.8% of patients experienced symptom and spleen response, respectively. Kaplan-Meier estimates of median progression-free and overall survival from initiation were 23.8 months (95% CI, 21.1-27.6) and 29.8 months (95% CI, 23.9-NE), respectively. CONCLUSION: These findings demonstrate real-world FEDR effectiveness among patients with myelofibrosis who discontinued RUX.