Acetylcysteine for the Treatment of Myeloproliferative Neoplasms

Inclusion Criteria

• >= 18 years of age
• Have a diagnosis of essential thrombocythemia (ET), polycythemia vera (PV), or myelofibrosis (MF) according to the 2016 World Health Origination (WHO) criteria
• Has not taken interferon-alpha (any formulation) or a JAK inhibitor (such as ruxolitinib, fedratinib or pacritinib) for treatment of MPN in the past 28 days before enrollment
• May continue on current MPN treatment, including aspirin, hydroxyurea, or anagrelide. Therapeutic phlebotomies should continue per the patient’s usual regimen
• Has not taken N-Acetylcysteine (N-AC) or preparations containing N-AC in the past 28 days before enrollment
• Baseline MPN- total symptom score (TSS) score of >= 10 at the time of screening
• Peripheral blast count < 10% during screening
• Free of other active or metastatic malignancies other than localized skin cancer
• Amenable to blood draws and symptom assessments
• Agree to the use of contraceptives. Female subjects of childbearing potential and their male partners, or male subjects who have female partners of childbearing potential, should both use an effective contraception method during the study and continue to use contraception for 60 days after the last dose of study drug

Exclusion Criteria

• Eastern Cooperative Oncology Group (ECOG) questionnaire score of >= 3
• Currently pregnant or planning on being pregnant within the study period
• Currently breastfeeding
• Known uncontrolled active viral or bacterial infection
• Serum creatinine clearance less than 50 ml/min (calculated with Cockroft-Gault formula)
• Bilirubin more than 1.5 mg/dl except for Gilbert’s disease
• Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) more than 2X upper normal limit or has radiologic evidence of liver cirrhosis
• Platelets < 100 x 10^9/L
• Hemoglobin (Hgb) < 10 g/dL
• Absolute neutrophil count (ANC) < 0.75 x 10^9/L
• Known history of allergic reaction to N-AC