Study closed to enrollment

Inclusion Criteria:

• Diagnosis of one of the following:
  • PMF per the revised World Health Organization (WHO) criteria
  • Post-ET/PV MF per the IWG-MRT criteria
• High-risk or Intermediate-2 risk MF (as defined by the Dynamic International Prognostic Scoring System [DIPSS-plus])
• Life expectancy of ≥ 12 weeks
• Able to provide informed consent and be willing to sign an informed consent form
• Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2
• Serum glutamic oxaloacetic transaminase (SGOT) (aspartate aminotransferase [AST]) ≤ 2.5 x upper limit of normal (ULN) (or ≤ 5 x ULN if in the investigator's opinion the elevation is due to extramedullary hematopoiesis)
• Serum glutamic pyruvate transaminase (SGPT) alanine aminotransferase (ALT) ≤ 2.5 x upper limit of normal (ULN) (or ≤ 5 x ULN if in the investigator's opinion the elevation is due to extramedullary hematopoiesis)
• Total bilirubin ≤ 3.0 mg/dL (or direct bilirubin < 1 mg/dL)
• Creatinine ≤ 3.0 mg/dL
• Absolute neutrophil count ≥ 1000/uL
• Platelet count ≥ 50,000/uL
• Absence of active treatment with systemic anticoagulation and a baseline prothrombin time (PT) and activated partial thromboplastin time (aPTT) that does not exceed 1.5 x ULN
• Females of childbearing potential must have a negative pregnancy test ≤ 7 days prior to registration, unless they are surgically sterile for at least 3 months (i.e., hysterectomy), OR postmenopausal for at least 12 months (follicle-stimulating hormone [FSH] >30 U/mL)
• Females of childbearing potential must agree to take appropriate precautions to avoid pregnancy (with at least 99% certainty) from screening through end of study; permitted methods for preventing pregnancy must be communicated to study subjects and their understanding confirmed
• Males must agree to take appropriate precautions to avoid fathering a child (with at least 99% certainty) from screening through follow-up; permitted methods for preventing pregnancy should be communicated to the subjects and their understanding confirmed

Exclusion Criteria:

• Females who are pregnant or are currently breastfeeding
• Any chemotherapy (e.g., hydroxyurea), immunomodulatory drug therapy (e.g., thalidomide), immunosuppressive therapy, corticosteroids > 10 mg/day prednisone or equivalent, growth factor treatment (e.g., erythropoietin) or Janus kinase (JAK) inhibitor therapy ≤ 14 days prior to registration
• Subjects with another active malignancy
  • Note: patients with early stage squamous cell carcinoma of the skin, basal cell carcinoma of the skin or cervical intraepithelial neoplasia are eligible for enrollment
• Known positive status for human immunodeficiency virus (HIV)
• Any unresolved toxicity greater or equal to grade 2 from previous anticancer therapy, except for stable chronic toxicities not expected to resolve
• Incomplete recovery from any prior surgical procedures or had surgery ≤ 4 weeks prior to registration, excluding the placement of vascular access
• Presence of acute active infection requiring antibiotics
• Uncontrolled intercurrent illness or any concurrent condition that, in the Investigator's opinion, would jeopardize the safety of the patient or compliance with the protocol