Older matched sibling donor versus young haplo-identical donor for elderly patients with acute myeloid leukemia

Researchers from the European Society for Blood and Marrow Transplantation (EBMT) conducted a large registry-based analysis comparing haploidentical donors (HID) and older matched sibling donors (MSD) in older patients with acute myeloid leukemia (AML). Published in Blood Advances, the study evaluated outcomes in transplant patients in first complete remission, aiming to clarify whether younger haploidentical donors provide superior results compared with older matched siblings. The research addresses a clinically relevant question in donor selection for allogeneic hematopoietic cell transplantation.

AML treatment often requires allogeneic transplantation, however, donor choice significantly influences patient survival. Matched sibling donors have been the traditional gold standard, yet in older AML patients these donors are typically older siblings, which may negatively affect outcomes. In contrast, haploidentical offspring donors are younger and are increasingly being used. With this said, direct comparisons between these donor types in a homogeneous older AML population are limited, and this study examined relapse incidence, non-relapse mortality, leukemia-free survival, overall survival, and graft-versus-host disease–free/relapse-free survival.

Among 1,247 patients (721 MSD, 526 HID), HID recipients showcased significantly lower relapse incidence (HR 0.62, 95% CI 0.46–0.84, p = 0.002) compared with MSD. However, this advantage was offset by higher non-relapse mortality (HR 1.72, 95% CI 1.20–2.46, p = 0.003). Leukemia-free and overall survival were not significantly different, however, subgroup analysis demonstrated that adverse cytogenetics strongly predicted worse outcomes: LFS HR 1.65 (95% CI 1.27–2.12, p = 0.0001) and OS HR 1.75 (95% CI 1.40–2.19, p < 0.0001). A Karnofsky performance status of 90 or higher improved overall survival (HR 0.74, 95% CI 0.59–0.93, p = 0.01), with the results summarized above suggesting that haploidentical donors may reduce relapse in older AML patients at the cost of increased treatment-related mortality, underscoring the importance of integrating donor age, cytogenetic risk, and patient fitness into transplant decision-making.

Reference:

Poire X, Labopin M, Polge E, et al. Older matched sibling donor versus young haplo-identical donor for elderly patients with acute myeloid leukemia. Blood Adv. Published online July 16, 2025.

https://doi.org/10.1182/bloodadvances.2024015582