GVHD prophylaxis with PTCy for HCT with MMUD
Raiola A, Bruno B, Risitano AM, et al. Post Transplant Cyclophosphamide as GVHD Prophylaxis in Patients Receiving Mismatched Unrelated HCT: The PHYLOS Trial. Blood Advances. 2025; (doi: 10.1182/bloodadvances.2024015173).
Phase II evidence supports the use of post-transplant cyclophosphamide (PTCy) as prophylaxis against acute graft-versus-host disease (aGVHD) in patients undergoing hematopoietic cell transplantation (HCT) from a mismatched unrelated donor (MMUD). In the PHYLOS study, investigators calculated the 100-day cumulative incidence (CI) of aGVHD among 77 patients with acute myeloid malignancies between January 2020 and November 2022. For the single-arm study, patients who underwent HCT from a MMUD received PTCy with busulfan and fludarabine. The rate at 100 days was 18.2% for grade II-IV disease and 6.5% for grade III-IV aGVHD. At 12 months, the CI of chronic GVHD was 13.4% (95% CI: 6.9-22.1). PTCy also mediated other clinical improvements in MMUD transplantation, including a low 1-year non-relapse mortality rate of 9.1% (95% CI: 4.0-16.9); relapse rate of 23.8% (95% CI: 14.9-33.9); and respective 1-year overall survival and graft-relapse-free survival rates of 78.6% (95% CI: 67.4-86.3) and 55.3% (95% CI: 43.4-65.7).