FDA approves momelotinib for the treatment of patients with anemic myelofibrosis

On September 15, 2023, the U.S. Food and Drug Administration granted approval to momelotinib, an oral inhibitor of Janus kinase (JAK) 1, JAK2, and activin A type 1 receptor (ACVR1), for the treatment of patients with anemic myelofibrosis (MF).¹ This approval includes patients with primary and secondary MF, regardless of prior treatment, including those with hemoglobin levels <10 g/dL.²

The decision was based on data from MOMENTUM and a subset of patients with anemia from SIMPLIFY-1.

MOMENTUM²

A summary of the pivotal data from MOMENTUM is shown in Table 1.

Table 1. Key safety and efficacy data from MOMENTUM*

*Data from Verstovsek, et al.2
Outcome measure (%, unless otherwise stated)	Momelotinib cohort (N = 130)	Danazol cohort (N = 65)
Total Symptom Score reduction of ≥50%	25	9
Adverse events (Grade ≥3)
Anemia	61	75
Thrombocytopenia	28	26
Acute kidney injury	3	9
Pneumonia	2	9

SIMPLIFY-1¹

In the population of patients with anemia and MF from SIMPLIFY-1:

• Both the momelotinib and ruxolitinib cohorts had comparable spleen volume reduction, but a lower symptom response rate was observed with momelotinib
• The most commonly occurring adverse events in the momelotinib cohort included: thrombocytopenia, hemorrhage, bacterial infection, fatigue, dizziness, diarrhea, and nausea.