MOMENTUM showed that momelotinib, a JAK inhibitor that also eases anaemia, relieved symptoms and shrank spleens better than danazol in people with myelofibrosis who were anaemic after earlier JAK inhibitor treatment.
Anaemia is the weak point of the first JAK inhibitors: ruxolitinib and fedratinib worsen it. Momelotinib inhibits JAK1, JAK2 and ACVR1, the last of which lowers hepcidin and improves red cell production. MOMENTUM randomised 195 patients with symptomatic myelofibrosis, anaemia and prior JAK inhibitor treatment to momelotinib or to danazol, an androgen used for anaemia in this disease. The primary endpoint was the proportion with a 50 percent or greater reduction in total symptom score at week 24.
Momelotinib met the primary endpoint and also improved transfusion independence and spleen volume response compared with danazol. It was approved in the United States in September 2023 for myelofibrosis with anaemia, the first JAK inhibitor labelled for that group.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
195 enrolled.
Difference 16% (95% CI 6 to 26)
Source| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Total symptom score response (>=50% reduction) at week 24primary | Momelotinib 200 mg | 130 | 25% | - | 0.0095 | link |
| Danazol 300 mg twice daily | 65 | 9% | ||||
| Grade 3 or higher anaemia (laboratory) | Momelotinib 200 mg | 130 | 61% | - | - | link |
| Danazol 300 mg twice daily | 65 | 75% | ||||
| Grade 3 or higher thrombocytopenia (laboratory) | Momelotinib 200 mg | 130 | 28% | - | - | link |
| Danazol 300 mg twice daily | 65 | 26% |
The full inclusion and exclusion criteria are on the registry record. Read 2026-10-07. Recruiting overall does not mean a particular site is open; ask the study team.
ClinicalTrials.gov data courtesy of the US National Library of Medicine.
Shares Primary myelofibrosis, Myeloproliferative neoplasms (PV, ET, myelofibrosis) and the tag subtype-trials.
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Every source this page cites, grouped by who published it. Grouping is read from the web address, not assigned by hand.
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