First complete remission favours haploidentical haematopoietic stem cell transplantation with post‐transplant cyclophosphamide over cord blood transplantation in acute lymphoblastic leukaemia

Summary To assess the benefits of HLA‐haploidentical haematopoietic stem cell transplantation using post‐transplant cyclophosphamide (PTCy‐haplo) relative to those of umbilical cord blood (UCB) transplantation in acute lymphoblastic leukaemia (ALL), we analysed 1999 patients (PTCy‐haplo, 330; UCB, 1669), using the nationwide Japanese registry. PTCy‐haplo was associated with a significantly higher relapse rate, but lower non‐relapse mortality, which results in overall survival and disease‐free survival, comparable to those of UCB. Among patients in CR1, PTCy‐haplo showed a significantly higher survival than UCB regardless of the CD34+ cell dose. Our findings provide valuable insights into the donor selection algorithm in allogeneic HSCT for adult patients with ALL.