GSK Canada’s submission for momelotinib for the treatment of myelofibrosis accepted for review by Health Canada

  • Health Canada’s acceptance of the submission follows that of the Ministry of Health, Labour and Welfare (WHLW) in Japan and approval by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA).
  • Regulatory submission includes data from pivotal trials addressing key clinical manifestations of myelofibrosis, namely splenomegaly, constitutional symptoms and anemia.

MISSISSAUGA, ON - GSK announces that Heath Canada has accepted into review the New Drug Submission (NDS) for momelotinib, a potential new medicine with a differentiated mechanism of action that may help address the significant medical needs of myelofibrosis patients, especially those with anemia. The NDS is based on key phase III trials SIMPLIFY-1 and MOMENTUM.

Myelofibrosis is a rare blood cancer that can lead to splenomegaly (enlarged spleen); constitutional symptoms such as fatigue, night sweats, and bone pain; and severely low blood counts, including anemia and thrombocytopenia. [1][2][3] Approximately 82% [4] of patients diagnosed with myelofibrosis are intermediate or high-risk and about one-third to one-half of patients are anemic at the time of diagnosis.[5][6][7] The majority of myelofibrosis patients are expected to develop anemia over the course of the disease, and those who are transfusion dependent have a poor prognosis and shortened survival.[8][9][10][11][12][13][14][15][16]

Momelotinib is an investigational product that is not currently authorized for sale in Canada.

About momelotinib

Momelotinib has a differentiated mechanism of action, with inhibitory ability along three key signaling pathways: Janus kinase (JAK) 1, JAK2, and activin A receptor, type I (ACVR1). [17][18][19][20] Inhibition of JAK1 and JAK2 may improve constitutional symptoms and splenomegaly.[17][19][20] Additionally, inhibition of ACVR1 leads to a decrease in circulating hepcidin, which is elevated in myelofibrosis and contributes to anemia. [17][18][19][20] 

About myelofibrosis

Myelofibrosis is a rare blood cancer that disrupts the body’s normal production of blood cells as a result of dysregulated JAK-signal transducer and activator of transcription protein signaling. The clinical hallmarks of myelofibrosis are progressive splenomegaly (enlarged spleen), anemia and debilitating symptoms attributable to ineffective hematopoiesis and excessive production of proinflammatory cytokines. [21] Myelofibrosis patients with anemia require additional supportive care, including transfusions, and have poor outcomes.[22][23] An estimated 1,400-2,177 patients are living with myelofibrosis in Canada with an estimated 3 in 500,000 people worldwide affected. [24][25]

About the pivotal SIMPLIFY-1 clinical trial

SIMPLIFY-1 was a global randomized, double-blind, phase III study that compared the safety and efficacy of momelotinib to ruxolitinib in patients with myelofibrosis who had not received prior treatment with a JAK inhibitor.

About the pivotal MOMENTUM clinical trial

MOMENTUM was a global, randomized, double-blind phase III clinical trial that compared the safety and efficacy of momelotinib to danazol in patients with myelofibrosis who were symptomatic and anemic and had been previously treated with an approved JAK inhibitor. The trial was designed to evaluate the safety and efficacy of momelotinib for treating and reducing key hallmarks of the disease: symptoms, blood transfusions (due to anemia) and splenomegaly.

GSK in oncology

GSK is committed to maximizing patient survival through transformational medicines, with a current focus on breakthroughs in immuno-oncology and tumor-cell targeting therapies, and development in hematologic malignancies, gynecologic cancers and other solid tumors. Our goal is to achieve a sustainable flow of new treatments based on a diversified portfolio of investigational medicines utilizing modalities such as small molecules, antibodies, antibody-drug conjugates, and cell therapy, either alone or in combination.

About GSK

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[18] Asshoff M, et al. Momelotinib inhibits ACVR1/ALK2, decreases hepcidin production, and ameliorates anemia of chronic disease in rodents. Blood. 2017;129(13):1823-1830.

[19] Oh S, et al. ACVR1/JAK1/JAK2 inhibitor momelotinib reverses transfusion dependency and suppresses hepcidin in myelofibrosis phase 2 trial. Blood Adv. 2020;4(18):4282-4291.

[20] Verstovsek S, et al. Momelotinib versus danazol in symptomatic patients with anaemia and myelofibrosis (MOMENTUM): results from an international, double-blind, randomised, controlled, phase 3 study. The Lancet. 2023;401(10373):269-280.

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[23] Naymagon L, Mascarenhas J. Myelofibrosis-Related Anemia: Current and Emerging Therapeutic Strategies. Hemasphere. 2017 Dec 20;1(1):e1. doi: 10.1097/HS9.0000000000000001. PMID: 31723730; PMCID: PMC6745971.

[24] Heppner et al. BMC Res Notes (2019) 12:286

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