Safety Study Evaluating Twice-Daily Administration of Momelotinib in Primary Myelofibrosis or Post-Polycythemia Vera or Post-Essential Thrombocythemia Myelofibrosis

Exclusion Criteria

• •Any chemotherapy (e.g., hydroxyurea), immunomodulatory drug therapy (e.g., thalidomide), immunosuppressive therapy, corticosteroids \>10 mg/day prednisone or equivalent, or growth factor treatment (e.g., erythropoietin) within 14 days prior to initiation of study drug.
• •Incomplete recovery from major surgery within four weeks of study entry.
• •Radiation therapy within four weeks of study entry.
• •Women of childbearing potential, unless surgically sterile for at least 3 months (i.e., hysterectomy), OR postmenopausal for at least 12 months (FSH \> 30 U/mL), OR unless they 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.
• •Men who partner with a woman of childbearing potential, unless they agree to take appropriate precautions to avoid pregnancy (with at least 99% certainty) from screening through to the end of study. Permitted methods for preventing pregnancy must be communicated to study subjects and their understanding confirmed.
• •Females who are pregnant or are currently breastfeeding.
• •Known positive status for HIV.
• •Positive serologic testing for hepatitis B (HBsAg and HBcAb total) and hepatitis C (anti-HCV)
• •Diagnosis of another malignancy unless free of disease for at least three years following therapy with curative intent. Patients with early-stage basal cell or squamous cell skin cancer, cervical intraepithelial neoplasia, cervical carcinoma in situ or superficial bladder cancer may be eligible participate at the Investigator's discretion.
• •Any acute active infection.
• •Cardiac dysrhythmias requiring treatment, or prolongation of the QTc (Fridericia) interval to \>480 at pre-study screening, unless attributable to pre-existing bundle branch block.
• •Presence of ≥ grade 2 peripheral neuropathy.
• •Uncontrolled congestive heart failure (New York Heart Association Classification 3 or 4), uncontrolled or unstable angina, myocardial infarction, cerebrovascular accident, or pulmonary embolism within 3 months prior to initiation of study drug.
• •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.