Danazol Is Outperformed by Momelotinib in Symptomatic, Anemic Myelofibrosis

In a phase 3 trial involving patients with symptomatic and anemic myelofibrosis, momelotinib outperformed danazol for important outcomes.

Momelotinib reduced symptoms, increased spleen size, and there was a tendency for overall survival to improve.

At the EHA 2022 Hybrid Congress, Srdan Verstovsek, MD, Ph.D., of the University of Texas MD Anderson Cancer Center in Houston, presented these findings from the MOMENTUM trial.

In the MOMENTUM trial, which has the ClinicalTrials.gov identifier NCT04173494, 195 patients with symptomatic and anemic myelofibrosis who had previously undergone treatment with a JAK inhibitor were enrolled and randomly assigned.

Momelotinib 200 mg/day (n = 130) or danazol 600 mg/day (n = 65) were given to patients at random in combination with placebo. After giving patients their prescribed medication for 24 weeks, momelotinib became available off-label.

In the momelotinib arm and the danazol arm, the median ages at baseline were 71 and 72 years, respectively. 60 percent and 70.8% of patients, respectively, had primary myelofibrosis, and the majority of them carried the JAK2V617F mutation (74.6 percent and 78.5 percent, respectively).

The main outcome was the total symptom score (TSS) response rate at week 24. Transfusion independence at week 24 and splenic response rates (SRRs) of between 25% and 35% reduction from baseline were important secondary goals.

Primary and key secondary endpoints were met. Momelotinib and danazol both significantly increased the TSS response rate, to 24.6 and 9.2 percent, respectively (P =.0095).

Patients in the momelotinib arm had a higher likelihood of a 25 or greater reduction in SRR from baseline to week 24 (40.0 percent vs 6.2 percent; P.0001) or a 35 or greater reduction in SRR from baseline to week 24 (23.1 percent vs 3.1 percent; P =.0006) than those on the danazol arm.

The main outcome was the total symptom score (TSS) response rate at week 24. Transfusion independence at week 24 and splenic response rates (SRRs) of between 25% and 35% reduction from baseline were important secondary goals.

Primary and key secondary endpoints were met. Momelotinib and danazol both significantly increased the TSS response rate, to 24.6 and 9.2 percent, respectively (P =.0095).

Patients in the momelotinib arm had a higher likelihood of a 25 or greater reduction in SRR from baseline to week 24 (40.0 percent vs 6.2 percent; P.0001) or a 35 or greater reduction in SRR from baseline to week 24 (23.1 percent vs 3.1 percent; P =.0006) than those on the danazol arm.