Real-World Insights and Personalized Approaches with JAK Inhibitors in Myelofibrosis

Real-world experience with JAK inhibitors in myelofibrosis generally mirrors clinical trial outcomes, demonstrating meaningful reductions in splenomegaly, symptom relief, and improved quality of life. Clinicians increasingly use biomarker profiles—such as JAK2, CALR, and MPL mutations—alongside clinical factors like cytopenias, comorbidities, and prior therapy response, to tailor treatment selection for individual patients. Anemia is a key consideration, with agents like momelotinib offering potential benefits for transfusion independence, while others may require supportive measures such as erythropoiesis-stimulating agents or transfusions. Safety profiles differ among the approved JAK inhibitors: ruxolitinib and fedratinib are generally well-tolerated but may cause thrombocytopenia or anemia, pacritinib is favored in patients with severe thrombocytopenia, and momelotinib may improve anemia while maintaining efficacy. These factors inform personalized strategies that optimize both efficacy and tolerability in routine clinical practice.