Aim
Although the fludarabine (F-araA)-treosulfan based toxicity reduced conditioning regimen has improved hematopoietic cell transplantation (HCT) outcome in patients with high-risk beta-thalassemia major (TM), rejection and regimen related toxicities (RRT) are still of major concern. This study aims to assess the role of F-araA pharmacokinetics (PK) and pharmacogenetics (PG) in a uniform cohort of patients with TM.