Transplant Outcomes in Patients with Ph+ Chronic Myeloid Leukemia: Haploidentical Donors Compared to Matched Sibling Donors and Matched/Mismatched Unrelated Donors: A Retrospective Analysis from the EBMT Chronic Malignancies Working Party (EBMT-CMWP)

Introduction: The role of allogeneic hematopoietic cell transplantation (allo-HCT) in Philadelphia-positive chronic myeloid leukemia (Ph+ CML) changed profoundly after the introduction of tyrosine kinase inhibitors (TKIs). Nevertheless, allo-HCT still represents the preferred treatment option for selected high-risk patients in Europe, with TKI resistance as the most common indication in first chronic phase (CP1). Reported survival outcomes for patients transplanted in CP1 with matched related (MRD), matched unrelated (MUD) and mismatched unrelated donors (MMUD) are generally good, but there are no published data on transplants from haploidentical donors (HD). In this retrospective study, we aimed to compare HD outcomes with those using MRD/MUD/MMUD.