A Calcineurin Inhibitor Free Graft Versus Host Disease Prophylaxis for Patients Undergoing Matched Related and Matched Unrelated Donor Allogeneic Hematopoietic Cell Transplant.

Post-transplantation cyclophosphamide (PTCy) and calcineurin inhibitor (CNI)-based graft versus host disease (GVHD) prophylaxis has been associated with lower rates of acute and chronic GVHD compared with the traditional prophylaxis of CNI and methotrexate (MTX) in matched related donor (MRD) and matched unrelated donor (MUD) allogeneic hematopoietic cell transplantation (allo-HCT). The combination of PTCy with sirolimus (PTCy-Siro) as CNI-free GVHD prophylaxis has shown promising results, with cumulative rates of grade II-IV acute and chronic GVHD in the range of 15% to 27% and 20% to 27%, respectively, in patients undergoing MRD, MUD, and haploidentical allo-HCT. We report a single-center, nonrandomized comparison of patients undergoing matched donor allo-HCT receiving PTCy-Siro with those receiving the standard GVHD prophylaxis of tacrolimus and methotrexate (Tac-MTX).