If a human leukocyte antigen (HLA)-matched related donor is unavailable, patients in need of hematopoietic cell transplant (HCT) may receive grafts from either haploidentical (haplo) or HLA-matched unrelated (MU) donors.
Researchers at the University of Kansas Medical Center, Kansas City, Kansas, retrospectively reviewed the records of all patients undergoing HCT from haplo or MUD donors to determine whether either donor type was associated with better outcomes.
All patients had at least 1 year of follow-up. From August 2016-July 2021, there were 176 haplo and 276 MU donors (39 versus 61%). Two conditioning intensities were used: myeloablative conditioning (MAC, n = 169, 37%) and reduced-intensity conditioning (RIC, n = 283, 63%).
For those who received MAC haplo HCT versus MUD HCT, rates of neutrophil engraftment, platelet engraftment, day-100 grade II-IV acute graft-versus-host disease (GVHD), 1-year chronic GVHD, relapse, non-relapse mortality (NRM), disease-free survival (DFS), and overall survival (OS) were similar.
For those who received RIC haplo HCT versus MUD HSCT, rates of neutrophil engraftment, day-100 grade II-IV acute GVHD, 1-year chronic GVHD, relapse, NRM, DFS, and OS, were similar, but platelet engraftment occurred 1 week earlier for those who received RIC MUD HCT.
Haplo and MUD HCT recipients had a similar relapse, 1-year DFS, and 1-year OS, when ignoring conditioning intensity.
Given the similarity in clinical outcomes, the authors concluded that HCT should not be delayed in favor of securing one type of donor or another, stating, “Allogeneic transplantation should be done promptly whenever indicated, utilizing either matched unrelated or haploidentical donors.”
Mushtaq MU, DeJarnette S, Al-Ramahi JS, et al. Outcomes with HLA-Matched Unrelated Donor Versus Haploidentical Hematopoietic Cell Transplantation: A Single-Center Experience. Abstract #302. Presented at the 2023 Tandem Meetings of ASTCT and CIBMTR; February 15-19, 2023; Orlando, FL.