Data from the phase 3 MOMENTUM study showed that momelotinib had a statistically significant benefit on symptoms, especially anemia and splenomegaly, in patients with myelofibrosis.

Momelotinib is an oral JAK1, JAK2, and ACVR1/ALK2 inhibitor being investigated for patients with myelofibrosis who are still anemic and symptomatic after being treated with an approved JAK inhibitor. 

In the phase 3, global, randomized, double-blind clinical trial evaluating momelotinib, patients were randomized 2:1 to momelotinib (n = 13) or danazol (n = 65). Patients assigned danazol were allowed to crossover to receive momelotinib at 24 weeks or earlier if there was confirmed symptomatic splenic progression. 

The primary endpoint of total symptom score of >50% was 25% in the momelotinib arm and 9% in the danazol arm (P =0.0095). The secondary endpoint of transfusion independence was 31% in the treatment arm and 20% in the control arm. The secondary endpoint of splenic response rate of >35% was 23% in the treatment arm and 3% in the control arm. 

Grade 3 or worse adverse events occurred in 54% of the treatment arm and in 65% of the control arm. Serious treatment-emergent adverse events occurred in 35% of the treatment arm and in 40% of the control arm. 

“As a clinician, I am thrilled to see data that confirm the potential of momelotinib as a treatment option for myelofibrosis patients who are anemic or at risk of becoming anemic,” said Ruben Mesa, MD, FACP, Director of the UT Health San Antonio MD Anderson Cancer Center and co-principal investigator of the study, in a press release. “Anemia of myelofibrosis is strongly correlated with reduced quality of life and a decrease in overall survival. Half of all myelofibrosis patients present with anemia at diagnosis and virtually all become anemic over time. With currently approved therapies being myelosuppressive, it’s wonderful to know that we may soon have such an effective treatment option for these patients.”

A new drug application for momelotinib is expected to be submitted to the FDA in the second quarter of 2022.