Myelofibrosis is a serious hematologic malignancy1,2

Myelofibrosis is life-threatening and debilitating.2,3 It is a progressive disease characterized by4

  • Increased splenomegaly
  • Worsening symptoms
  • Cytopenias

Survival varies in myelofibrosis but can be as little as ~2 years in high-risk patients.2*

Myelofibrosis classification

Myelofibrosis is one of several Philadelphia chromosome–negative, or Ph(–), myeloproliferative neoplasms (MPNs).5 MPNs, previously known as myeloproliferative disorders (MPDs), are rare diseases.6 About 16,000 to 18,500 people in the United States have myelofibrosis.7


Classification of Myelofibrosis and Myeloproliferative Neoplasms

BCR-ABL1 = breakpoint cluster region-Abelson leukemia virus oncoprotein 1; CML = chronic myelogenous leukemia; ET = essential thrombocythemia; MF = myelofibrosis; PV = polycythemia vera.

aOther diseases are also classified as MPNs by the World Health Organization (WHO). These include chronic neutrophilic leukemia; chronic eosinophilic leukemia, not otherwise categorized; hypereosinophilic syndrome; mast cell disease; and MPNs, unclassifiable.6

Myelofibrosis may be primary, secondary to polycythemia vera (post–polycythemia vera myelofibrosis) or secondary to essential thrombocythemia (post–essential thrombocythemia myelofibrosis).8

*As classified by the International Prognostic Scoring System (IPSS).2


  1. Lichtman MA, Tefferi A. Primary myelofibrosis. In: Kaushansky K, Lichtman MA, Beutler E, Kipps TJ, Seligsohn U, Prchal JT, eds. Williams Hematology. 8th ed. New York, NY, McGraw Hill Medical; 2010:1381-1399.
  2. Cervantes F, Dupriez B, Pereira A, et al. New prognostic scoring system for primary myelofibrosis based on a study of the International Working Group for Myelofibrosis Research and Treatment. Blood. 2009;113:2895-2901.
  3. Mesa RA, Schwager S, Radia D, et al. The Myelofibrosis Symptom Assessment Form (MFSAF): an evidence-based brief inventory to measure quality of life and symptomatic response to treatment in myelofibrosis. Leuk Res. 2009;33:1199-1203.
  4. Verstovsek S, Kantarjian H, Mesa RA, et al. Safety and efficacy of INCB018424, a JAK1 and JAK2 inhibitor, in myelofibrosis. N Engl J Med. 2010;363:1117-1127.
  5. Verstovsek S. Therapeutic potential of Janus-activated kinase-2 inhibitors for the management of myelofibrosis. Clin Cancer Res. 2010;16:1988-1996.
  6. Tefferi A, Vardiman JW. Classification and diagnosis of myeloproliferative neoplasms: the 2008 World Health Organization criteria and point-of-care diagnostic algorithms. Leukemia. 2008;22:14-22.
  7. Data on file. Incyte Corporation.
  8. Mesa RA, Verstovsek S, Cervantes F, et al. Primary myelofibrosis (PMF), post polycythemia vera myelofibrosis (post-PV MF), post essential thrombocythemia myelofibrosis (post-ET MF), blast phase PMF (PMF-BP): consensus on terminology by the international working group for myelofibrosis research and treatment (IWG-MRT). Leuk Res. 2007;31:737-740.
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MOA of Jakafi

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Symptoms Efficacy

Superior improvements in core symptoms of myelofibrosis with Jakafi.


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