A substantial proportion of patients with low- or intermediate-1–risk myelofibrosis experience disease progression, according to findings from the prospective, observational MOST trial (NCT02953704). The data, presented at the 2024 EHA Congress, underscore the need for vigilant monitoring and the development of therapies that can alter the disease course.
Disease Progression in Low-Risk Myelofibrosis
The MOST trial, which collected disease progression data for patients with low- or intermediate-1–risk myelofibrosis, revealed that 58.5% of patients in cohort A (n = 205) met at least one criterion for disease progression after a median follow-up of less than 53 months. Among those who experienced progression, 53.3% met one criterion, 22.5% met two criteria, and 24.2% met at least three disease progression criteria.
Common Progression Criteria
The most common progression criteria observed in cohort A were a hemoglobin level of less than 10 g/dL (47.5%) and a platelet count of less than 100 x 109/L (31.7%). These findings suggest that anemia and thrombocytopenia are critical indicators of disease progression in this patient population.
Clinical Implications and Unmet Needs
Aaron Gerds, MD, from the Cleveland Clinic Taussig Cancer Institute, emphasized that while time to progression in low-risk myelofibrosis is often considered in years, the MOST trial demonstrated that a majority of patients experienced disease progression within the study period. He noted that patients with low-risk myelofibrosis, even those initially presenting with mild symptoms or being asymptomatic, require close monitoring due to the risk of disease progression, particularly within the first year following diagnosis.
Dr. Gerds advocates for the development of therapies that can modify the disease's underlying course rather than merely managing symptoms. The high proportion of patients experiencing disease progression in the MOST trial highlights the necessity for additional therapies targeting the root causes of myelofibrosis progression.
