Inclusion Criteria:  Body weight ≥40.0 kg and ≤100 kg at screening Documented diagnosis of beta-thalassemia or Hb E/beta-thalassemia Red blood cell (RBC) transfusion dependence, defined as at least 6 RBC units in the 24 weeks prior to randomization and no transfusion-free period for ≥35 days during that period Ability to understand the requirements of the study and provide written informed consent  Exclusion Criteria:  Documented diagnosis of Hb S/beta-thalassemia, alpha-thalassemia, or delta beta (δβ)-thalassemia, or hereditary persistence of foetal Hb. History of partial or total splenectomy within 4 months prior to screening. History of myocardial iron overload Chronic liver disease or history of liver cirrhosis Clinically relevant renal disease History or clinically important finding of cardiac disorders History of clinically significant lung disease Uncontrolled hypertension (> Grade 1 according to NCI CTCAE current version) Unable to take and absorb oral medications. Pregnancy or breastfeeding History of drug or alcohol abuse within 2 years prior to screening History or concomitant solid tumors and/or hematological malignancies unless resolved in the ≥5 past years.