Momelotinib'S Spleen, Symptom And Anemia Efficacy Is Maintained In Intermediate/High Risk Myelofibrosis Patients With Thrombocytopenia

Momelotinib (MMB), a JAK1, JAK2 and ACVR1 inhibitor, has demonstrated clinically comparable splenic and symptomatic benefits to ruxolitinib (RUX), the standard-of-care JAK1/JAK2 inhibitor for myelofibrosis (MF), a condition marked by splenomegaly, constitutional symptoms and progressive anemia and thrombocytopenia. MMB also uniquely restores iron homeostasis and red blood cell production, reduces or eliminates the need for transfusions and improves or maintains platelet (PLT) counts. Consistent with MMB’s differentiated biological profile, low myelosuppressive potential and favorable hematological tolerability, prolonged, near-maximal MMB dose intensity can be maintained regardless of underlying PLT values. In contrast, RUX’s hematological toxicity profile necessitates attenuated starting doses for thrombocytopenic (TCP) patients with PLTs <200 × 109/L and substantive, progressive dose reduction to mitigate against RUX-induced thrombocytopenia. Here we report post-hoc comparative efficacy analyses for RUX and MMB for spleen, symptom and transfusion independence (TI) response in patients with a baseline PLTs <150 × 109/L versus the ITT populations from the two previously-completed global Phase 3 SIMPLIFY studies.