Consistent with prior data, and reflecting momelotinib’s differentiated pharmacological profile, our new long-term safety analyses continue to show a rapid and sustained increase in hemoglobin levels during momelotinib therapy, in contrast to the significant decrease in hemoglobin for patients receiving ruxolitinib. Patients treated with momelotinib also experienced significantly higher mean platelet counts compared to those receiving ruxolitinib. Importantly, patients who switched from ruxolitinib to momelotinib also achieved a sustained improvement in both hemoglobin and platelets. In addition to an absence of significant rates of high-grade hematological toxicities, long-term tolerability was favorable with no new safety signals or evidence of cumulative toxicity. Notably, this was achieved with most patients receiving full-dose momelotinib.” Prof. Claire Harrison, Guy’s and St. Thomas’ NHS Foundation Trust, London, United Kingdom.

“Momelotinib’s safety profile and durable anemia benefits facilitated sustained dose intensity across the continuum of JAK inhibitor naïve and previously JAK inhibitor treated myelofibrosis patients. While the starting doses for ruxolitinib were often attenuated due to low platelets, further reductions in dose intensity were also commonly required for ruxolitinib. In contrast, momelotinib was initiated at full dose for all subjects enrolled to the SIMPLIFY studies and high dose intensity was maintained in the majority over extended durations. The ability to safely dose momelotinib sustainably at high dose intensity likely facilitates its ability to durably control the cardinal features of myelofibrosis, namely anemia, constitutional symptoms, and splenomegaly. Furthermore, patients who switch from ruxolitinib to momelotinib saw an immediate and sustained improvement in dose intensity, suggesting a link to the corresponding improvements in hemoglobin and platelets noted by Prof. Harrison. These data suggest that momelotinib may be an optimal therapy in myelofibrosis patients, in particular those experiencing hematological toxicity and disease-related myelosuppression, which are significant unmet needs in this disease.”