A Study of Etavopivat in Patients With Thalassemia or Sickle Cell Disease

Open to people ages 12-65

• Provision of consent
• Female patients of childbearing potential must use acceptable methods of contraception, male patients are willing to use barrier methods of contraception

Cohort A (Sickle Cell Disease Transfusion Cohort)

• Confirmed diagnosis of sickle cell disease
• Chronically red blood cell transfused (sample or exchange [manual or via electrophoresis]) for primary stroke prevention or due to previous stroke. Chronic red blood cell transfusion is defined as: ≥ 6 red blood cell units in the previous 24 weeks before the first dose of study treatment and no transfusion-free period for > 35 days during that period
• At least 24 months of chronic monthly red blood cell transfusions for secondary stroke prevention/treatment of primary stroke (initial completed overt clinical stroke with documented infarction on brain computed tomography [CT] or magnetic resonance imaging [MRI])
• Prior to screening OR at least 12 months of chronic RBC transfusions for primary stroke prevention (abnormal TCD) prior to screening
• Documented adequate monthly transfusions with average HbS ≤ 45% (the upper limit of the established academic community standard) for the previous 12 weeks of red blood cell transfusions before the first dose of study treatment

Cohort B (Thalassemia Transfusion Cohort)

• Documented diagnosis of β-thalassemia, Hemoglobin E/ β-thalassemia or Hemoglobin H (α-thalassemia), or other thalassemia variant
• Chronically transfused, defined as: ≥ 6 red blood cell units in the previous 24 weeks before the first dose of study treatment and no transfusion-free period for > 35 days during that period

Cohort C (Thalassemia Non-transfused Cohort)

• Documented diagnosis of β-thalassemia, Hemoglobin E/ β-thalassemia or Hemoglobin H (α-thalassemia), or other thalassemia variant
• Hemoglobin ≤ 10 g/dL

• Female who is breast feeding or pregnant
• Hepatic dysfunction characterized by:
  • Alanine aminotransferase (ALT) > 4.0 × upper limit of normal (ULN)
  • Direct bilirubin > 3.0 × ULN
  • History of cirrhosis
• Known human immunodeficiency virus (HIV) positivity
• Active hepatitis B or hepatitis C infection
• Severe renal dysfunction or on chronic dialysis
• History of malignancy within the past 2 years prior to treatment Day 1 requiring systemic chemotherapy and/or radiation.
  • Patients with malignancy considered surgically cured are eligible (eg, non- melanoma skin cancer, cancer of the cervix in-situ, ductal carcinoma in situ [Stage 1], Grade 1 endometrial cancer)
• History of unstable or deteriorating cardiac or pulmonary disease within 6 months prior to consent including but not limited to the following:
  • Unstable angina pectoris or myocardial infarction or elective coronary intervention
  • Congestive heart failure requiring hospitalization
  • Uncontrolled clinically significant arrhythmias
  • Symptomatic pulmonary hypertension