Patients With Low-Risk Myelofibrosis Have High Rate of Disease Progression

Over half of patients with low-risk myelofibrosis (MF) have evidence of disease progression, according to a study that will be presented at the 65th ASH Annual Meeting & Exposition, which is taking place December 9-12 in San Diego, California.

“Patients with low-risk MF are typically excluded from interventional clinical trials, thus data regarding the prognosis of this [patient] population are largely derived from retrospective analyses,” the researchers wrote.

In the prospective Myelofibrosis and Essential Thrombocythemia Observational Study (MOST) study, Michael R. Grunwald, MD, and colleagues analyzed 229 patients with a physician-reported diagnosis of MF (primary myelofibrosis, post-polycythemia vera myelofibrosis, or post-essential thrombocythemia myelofibrosis) and lack of any Dynamic International Prognostic Scoring System risk factors except for age (>65 years). Disease progression was defined as having at least 1 of the following criteria:

• Hemoglobin <10 g/dL
• Platelets <100×10⁹/L
• Presence of constitutional symptoms (weight loss, fever, or sweats)
• New or worsening splenomegaly
• Blasts >1%
• White blood count >25×10⁹/L
• Death due to disease progression
• Leukemic transformation
• >1 red blood cell transfusion

According to the results, nearly 60% of patients with low-risk MF showed signs of disease progression, and the average time from first to second disease progression was approximately 2 years, indicating a slow but increasing level of progression over the study’s duration.

“This real-world observational analysis from MOST is the first prospective analysis of disease progression in low-risk myelofibrosis,” the researchers concluded. “These data provide real-world insight into disease progression rate in [patients] with low-risk myelofibrosis.”

Reference

Grunwald M, Gerds A, Agarwal A, et al. High rate of disease progression in patients with low-risk myelofibrosis (MF) enrolled in the prospective, real-world MOST study. Abstract #3803. Presented at the 65th ASH Annual Meeting & Exposition; December 9-12, 2023; San Diego, California.