MOMENTUM Clinical Trial

MOMENTUM (NCT04173494) is a randomized, double-blind Phase 3 clinical trial of momelotinib versus danazol (n=180; 2:1) in symptomatic, anemic patients previously treated with an approved JAK inhibitor. The study is designed to confirm [in a statistically compelling manner] the unique benefits of momelotinib on all three hallmarks of myelofibrosis (MF): symptoms, anemia and splenomegaly.

The primary endpoint of the study is the MFSAF Total Symptom Score (TSS) response rate at Week 24. Secondary endpoints include confirmatory measures of anemia benefit and splenic response rate.

Danazol has been selected as an appropriate treatment comparator given its use to ameliorate anemia in myelofibrosis patients, as recommended by NCCN and ESMO guidelines. Patients will be randomized 2:1 to receive either momelotinib or danazol. After 24 weeks of treatment, patients on danazol will be allowed to crossover to receive momelotinib. Early cross-over to momelotinib is available for confirmed symptomatic splenic progression.

The study’s co-Chief Investigators are Dr. Srdan Verstovsek, Chief, Section for Myeloproliferative Neoplasms, Department of Leukemia, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas and Dr. Ruben Mesa, Director of the Mays Cancer Center, home to UT Health San Antonio MD Anderson Cancer Center. Both Dr. Verstovsek and Dr. Mesa are world-renowned clinician scientists in the myeloproliferative neoplasm field. Dr. Verstovsek and Dr. Mesa have been involved in the development of most of the investigational and approved agents for the treatment of myelofibrosis. In particular, Dr. Verstovsek and Dr. Mesa have been involved in the development of momelotinib since 2011, both as advisors and as clinical investigators.

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Expanded Access Protocol

Sierra Oncology is a late stage drug development company focused on achieving the successful registration and commercialization of momelotinib.

Expanded Access, also known as “compassionate use,” refers to the use of an investigational therapy outside of a clinical trial. This is a U.S. Food and Drug Administration (FDA) initiative that allows patients with serious illnesses, who have exhausted all other treatment options, the opportunity to access investigational drugs that are not yet approved. For more information on the FDA Expanded Access program, please see the FDA website on Expanded Access, and/or talk to your health care provider.

At this time, Sierra Oncology does not provide access to investigational therapies, except for patients who are enrolled in a clinical trial. Sierra Oncology understands the need for Expanded Access programs and may revise this policy at any time. For information on clinical trial participation and status updates, please check If you have additional questions, please speak with your health care provider or contact We anticipate acknowledging receipt of requests sent to this email within ten business days.


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