PTCy vs ATG for GvHD prophylaxis in 8/10 HLA-MMUD transplantation: An EBMT analysis

Moiseev et al. compared graft-versus-host disease (GvHD) prophylaxis with post-transplantation cyclophosphamide (PTCy) vs antithymocyte globulin (ATG) in 450 patients with hematological malignancies receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT) from 8/10 human leukocyte antigen (HLA) mismatched unrelated donors (MMUD) in a retrospective European Society for Blood and Marrow Transplantation (EBMT) registry analysis. Results were published in Bone Marrow Transplantation. Study endpoints included incidence and severity of acute GvHD (aGvHD) and chronic GvHD (cGvHD), non-relapse mortality (NRM), overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and GvHD-free-relapse-free survival (GRFS). 

 Key data: Overall, 21.1%, 55.7%, 50.4%, 28.5%, and 39.8% of patients achieved 2-year NRM, OS, PFS, CIR, and GRFS, respectively. PTCy was associated with reduced 100-day incidence of Grade 2–4 aGvHD (28.6% vs 38.2%; hazard ratio [HR], 0.63; p = 0.044) and Grade 3–4 aGvHD (5.9% vs 19.6%; HR, 0.31; p = 0.009) vs ATG. PTCy improved 2-year OS (HR, 0.63; p = 0.027) and GRFS (HR, 0.65; p = 0.011) vs ATG.  

Key learning: The findings show that allo-HSCT from 8/10 HLA-MMUD is a feasible option for patients with hematological malignancies, and the use of PTCy in GvHD prophylaxis improves outcomes.