Pacritinib Versus Best Available Therapy to Treat Myelofibrosis

Inclusion Criteria:

Intermediate -1 or -2 or high-risk Myelofibrosis (per Passamonti et al 2010)
Palpable splenomegaly ≥ 5 cm on physical examination
Total Symptom Score >13 on the MPN-SAF TSS 2.0, not including the inactivity question
Patients who are platelet or red blood cell transfusion-dependent are eligible
Adequate white blood cell counts (with low blast counts), liver function, and renal function
No spleen radiation therapy for 6-12 months
Last therapy for myelofibrosis was 2-4 weeks ago, including any erythropoietic or thrombopoietic agent
Not pregnant, not lactating, and agree to use effective birth control

Exclusion Criteria:

Prior treatment with a JAK2 inhibitor
History of (or plans to undergo) spleen removal surgery or allogeneic stem cell transplant
Ongoing gastrointestinal medical condition such as Crohn's disease, Inflammatory bowel disease, chronic diarrhea, or constipation
Cardiovascular disease, including recent history or currently clinically symptomatic and uncontrolled: congestive heart failure, arrhythmia, angina, QTc prolongation or other QTc risk factors, myocardial infarction
Other malignancy within last 3 years other than certain limited skin, cervical, prostate, breast, or bladder cancers
Other ongoing, uncontrolled illnesses (including HIV infection and active hepatitis A, B, or C), psychiatric disorder, or social situation that would prevent good care on this study
Life expectancy < 6 months