Antithymocyte globulin plus post-transplant cyclophosphamide combination as graft-versus-host disease prophylaxis in haploidentical peripheral blood stem cell transplantation for hematological malignancies

Background Post-transplant cyclophosphamide (PT-Cy) and calcineurin inhibitors used in peripheral blood haplo-identical stem cell transplantation (haploSCT) increase the risk of acute/chronic graft-versus-host disease (GVHD). Whether ATG/PT-Cy is feasible for Asian patients undergoing haploSCT is unclear, and an optimal strategy for GVHD prophylaxis is needed. Materials and methods We retrospectively analyzed 61 hematologic malignancy patients who underwent peripheral blood haploSCT using ATG/PT-Cy from January 2013 to December 2018. We also compared the effects of ATG/PT-Cy (ATG group; n = 61) with historical data from patients who underwent haploSCT using sirolimus/PT-Cy (non-ATG group; n = 22). Results Cumulative incidences of grades II–IV acute GVHD and moderate to severe chronic GVHD did not differ significantly. The ATG group had higher incidence of Epstein–Barr virus (EBV) reactivation, but neither group had post-transplant lymphoproliferative disorders. The ATG group also had a higher OS rate (2-year OS in ATG group vs. non-ATG group: 43.4% vs. 27.3%, respectively; P = 0.071). Conclusion ATG/PT-Cy is an acceptable strategy for GVHD prophylaxis in Asian patients undergoing haploSCT.