Post-Transplant Cyclophosphamide versus Antithymocyte Globulin in HLA-Mismatched unrelated Donors transplantation

Giorgia Battipaglia, Myriam Labopin, Nicolaus Kröger, Antonin Vitek, Boris Afanasyev, Inken Hilgendorf, Johannes Schetelig, Arnold Ganser, Didier Blaise, Maija Itälä-Remes, Jakob R Passweg, Francesca Bonifazi, Jurgen Finke, Annalisa Ruggeri, Arnon Nagler and Mohamad Mohty

Key Points

  • PTCY provides better outcomes compared to ATG in transplant from one-antigen mismatched unrelated donors for acute myeloid leukemia

  • Superiority of PTCY remains over ATG with the use of PBSC as stem cell source


The use of antithymocyte globulin (ATG) has represented the standard of care in graft-versus-host (GVHD) prophylaxis in patients undergoing mismatched unrelated donor (MMUD) transplant. The safety and feasibility of post-transplant cyclophosphamide (PTCY) in this setting has recently been reported, but no studies have compared to date the outcomes of PTCY versus ATG in a 9/10 MMUD transplant. Using the registry data of the ALWP of the EBMT we performed a matched-pair analysis comparing those two 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 as compared to ATG. Recipients of the former also showed higher leukemia-free and GVHD/relapse-free survival (GRFS). When performing a subgroup analysis including patients receiving peripheral blood stem cells, or being in complete remission (CR), or receiving the same associated immunosuppressive agents, superiority of PTCY over ATG was confirmed. Similarly to the haploidentical setting, use of PTCY is an effective anti GVHD prophylaxis also 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.

  • Submitted March 7, 2019.
  • Revision received July 2, 2019.
  • Accepted June 14, 2019.