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.

1st State Pavlov Medical University of St Petersburg Raisa Gorbacheva Memorial Research Institute for Paediatric Oncology Hematology and Transplantation St Petersburg Russia

Acute Leukemia Working Party of EBMT Paris France

Bologna University S Orsola Malpighi Hospital Institute of Hematology and Medical Oncology L and A Seràgnoli Bologna Italy

Bone Marrow Transplantation Centre University Hospital Eppendorf Hamburg Germany

Chaim Sheba Medical Center Tel Hashomer Israel

Department of Haematology Hemostasis Oncology and Stem Cell Transplantation Hannover Medical School Hannover Germany

Department of Medicine Hematology Oncology University of Freiburg Freiburg Germany

Department of Pediatric Hematology and Oncology IRCCS Bambino Gesù Children's Hospital Rome Italy; and

Hematology Department Federico 2 University Naples Italy

Hematology Department Hôpital Saint Antoine Service d'Hématologie et Thérapie Cellulaire Paris France

Hospital Saint Antoine Paris University UPMC INSERM U938 Paris France

Institute of Hematology and Blood Transfusion Servicio de Hematología Prague Czech Republic

Programme de Transplantation et Therapie Cellulaire Centre de Recherche en Cancérologie de Marseille Institut Paoli Calmettes Marseille France

Stem Cell Transplantation Unit HUCH Comprehensive Cancer Center Helsinki Finland

Universitaetsklinikum Dresden Medizinische Klinik und Poliklinik 1 Dresden Germany

Universitaetsklinikum Jena Klinik für Innere Medizin 2 Abt Hämatologie und Internistische Onkologie Jena Germany

University Hospital Hematology Basel Switzerland

Comment In

Blood. 2019 Sep 12;134(11):848-849. doi: 10.1182/blood.2019002284. PubMed

References provided by Crossref.org

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