The use of anti-thymocyte globulin (ATG) has represented the standard of care in graft-versus-host disease (GVHD) prophylaxis in patients undergoing a mismatched unrelated donor (MMUD) transplant. The safety and feasibility of posttransplant cyclophosphamide (PTCY) in this setting have been reported recently, but no study has compared the outcomes of PTCY vs ATG in 9/10 MMUD transplants. Using the registry data of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation, we performed a matched-pair analysis comparing those 2 strategies in a 9/10 MMUD setting. Ninety-three patients receiving PTCY were matched with 179 patients receiving ATG. A significantly lower incidence of severe acute GVHD was observed with PTCY compared with ATG. Recipients of the former also showed higher leukemia-free survival and GVHD/relapse-free survival (GRFS). When performing a subgroup analysis including patients receiving peripheral blood stem cells, being in complete remission, or receiving the same associated immunosuppressive agents, superiority of PTCY over ATG was confirmed. Similar to the haploidentical setting, use of PTCY is an effective anti-GVHD prophylaxis in the 9/10 MMUD transplant. Use of PTCY may also provide better outcomes in long-term disease control. These results need confirmation in large prospective randomized trials.

• MeSH
• Leukemia, Myeloid, Acute immunology   therapy   MeSH
• Antilymphocyte Serum administration & dosage   adverse effects   MeSH
• Cyclophosphamide administration & dosage   adverse effects   MeSH
• Adult MeSH
• Transplantation, Homologous MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Graft vs Host Disease prevention & control   MeSH
• Unrelated Donors * MeSH
• Transplantation Conditioning adverse effects   methods   MeSH
• Retrospective Studies MeSH
• Drug Administration Schedule MeSH
• Aged MeSH
• Histocompatibility Testing adverse effects   MeSH
• Hematopoietic Stem Cell Transplantation * adverse effects   methods   MeSH
• Transplantation Immunology MeSH
• Blood Grouping and Crossmatching adverse effects   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH