Momelotinib Provides Greater Transfusion Independence, Stability in MF

Momelotinib was associated with greater stability in red blood cell (RBC) transfusion intensity and freedom from transfusions compared with ruxolitinib in patients with myelofibrosis (MF) who were Janus kinase (JAK) inhibitor naïve, according to a longitudinal analysis of phase III data from the SIMPLIFY-1 and MOMENTUM trials.

Additionally, momelotinib “showed greater reduction in RBC transfusion burden from baseline versus [danazol] in patients with MF who were JAK inhibitor experienced,” stated lead author Ruben Mesa, MD, of Atrium Health Wake Forest Baptist Comprehensive Cancer Center in Winston-Salem, North Carolina. Dr. Mesa presented the analysis at the 65th ASH Annual Meeting and Exposition in San Diego, California.

SIMPLIFY-1 enrolled JAK inhibitor-naïve patients, whereas MOMENTUM enrolled symptomatic, anemic, and JAK inhibitor-exposed patients. In both studies, RBC transfusions were assessed over the 24-week treatment period and the 84 days before treatment initiation. Time-dependent transfusion burden was defined as the number of RBC units transfused.

In SIMPLIFY-1, 150 of 213 (70%) evaluable patients in the momelotinib group and 163 of 216 (76%) in the ruxolitinib group required zero RBC units transfused per 28 days at baseline. Among those patients, 142 of 150 (95%) in the momelotinib group versus 93 of 163 (57%) in the ruxolitinib group stayed at zero units transfused over 24 weeks. Additionally, the mean RBC transfusion burden per 28 days declined 0.10 ± 0.701 units from baseline with momelotinib, but it increased 0.39 ± 1.016 units with ruxolitinib.

In MOMENTUM, 26 of 130 (20%) and 11 of 65 (17%) patients in the momelotinib and danazol groups, respectively, required zero units transfused per 28 days at baseline. Of those, 46 of 130 (35%) on momelotinib versus 11 of 65 (17%) on danazol maintained a requirement of zero RBC units over 24 weeks. The mean transfusion burden per 28 days declined 0.86 ± 1.748 units and declined 0.28 ± 1.584 units from baseline with momelotinib and danazol, respectively.

“Across both trials, ≥85% of patients treated with [momelotinib] maintained or improved transfusion intensity,” Dr. Mesa and colleagues wrote.

Reference

Mesa R, Perkins A, Goh YT, et al. Longitudinal assessment of transfusion intensity in patients with JAK inhibitor- naïve or -experienced myelofibrosis treated with momelotinib in the phase 3 SIMPLIFY-1 and MOMENTUM trials. Abstract #3182. Presented at the 65th ASH Annual Meeting and Exposition; December 9-12, 2023; San Diego, California.