KEY TAKEAWAYS
- The MOST observational study aimed to assess PD/LT rates & compare patient features in lower-risk MF.
- In the analysis, around 33% had physician-reported PD, correlating with older age, unemployment, Black ethnicity, and ruxolitinib use.
Progressive myelofibrosis is linked to heightened bone marrow fibrosis, exacerbated anemia, increased circulating blasts, and potential leukemic transformation (LT). As per real-world data on Progressive disease (PD) and LT in lower-risk myelofibrosis there is limited resource available.
A longitudinal, non-interventional, prospective Myelofibrosis and Essential Thrombocythemia Observational Study (MOST) aimed to determine PD/LT incidence in lower-risk patients. It also determined the characteristics of patients with and without physician-reported PD who were diagnosed with DIPSS low/intermediate-1–risk myelofibrosis and were aged over 65 years.
The results showed that out of 232 enrolled patients, 204 were analyzed (cutoff: 09/30/2022; PD, n=59; without PD, n=134; unknown, n=11). The median (range) time from diagnosis to enrollment was 1.8 (0-38) years, and the median (range) enrollment duration was 4.4 (3.5-5.6) years. Compared to non-PD patients, PD patients were older (median [range]: 70.0 [35-88] vs. 66.5 [35-88] years), had a higher percentage of Black individuals (10.2% vs 5.2%), fewer were employed (20.3% vs. 44.4%), and more were unable to work (16.9% vs 2.3%).
Among PD patients, physician-reported PD indicators included changes in hematologic parameters (45.8%), spleen size (32.2%), myelofibrosis symptoms (27.1%), and blasts (13.6%). Additionally, 25.4% had LT, and 20.3% died from PD. In the low-risk group, 20.0% had changes in blasts, 20.0% had LT, and 10.0% died from PD, while in the intermediate-1 risk group, 10.3% had changes in blasts, 28.2% had LT, and 25.6% died from PD. Symptomology at enrollment was not significantly different between patients with and without PD.
At enrollment, 57.4% received myelofibrosis-directed monotherapy (hydroxyurea: 44.4%; ruxolitinib: 41.9%). Among those on monotherapy, more PD patients received ruxolitinib (62.9% vs 32.4%), and fewer received hydroxyurea (25.7% vs 51.4%) compared to those without PD. However, more patients receiving ruxolitinib vs. hydroxyurea at enrollment had intermediate-1–risk myelofibrosis (65.3% vs. 48.1%), palpable spleen (50.0% vs. 28.2%), and a longer median myelofibrosis duration from diagnosis to enrollment (2.6 vs. 1.1 years) and from diagnosis to PD (4.3 vs. 3.0 years).
The analysis of the MOST study showed that about one-third of patients experienced physician-reported PD. This subgroup, characterized by older age, lower employment rates, a higher proportion of Black individuals, and a greater likelihood of receiving ruxolitinib instead of hydroxyurea at enrollment, exhibited signs of progression, suggesting a higher utilization of ruxolitinib in myelofibrosis patients at a higher risk of PD.
Source: https://clml-soho2023.elsevierdigitaledition.com/400/index.html#zoom=true
Clinical Trial: https://clinicaltrials.gov/study/NCT02953704
Komrokji R, Grunwald MR, Braunstein E, Hamer-Maansson JE, Kalafut T, Mascarenhas J. Disease Progression and Leukemic Transformation in Patients With Lower‑Risk Myelofibrosis: An Analysis From the Myelofibrosis and Essential Thrombocythemia Observational Study (MOST). SOHO 2023. Abstract MPN-540.
