Among patients with hematologic cancers unlikely to find a human leukocyte antigen (HLA)–matched unrelated donor (MUD), no differences in transplant outcomes were found when a donor search prognosis strategy was used vs patients very likely to find a MUD, according to findings from a multicenter biological assignment trial (NCT03904134) conducted by the Blood and Marrow Transplant Clinical Trials Network (BMT CTN 1702) published in the Journal of Clinical Oncology.1
Specifically, among 1751 patients across 47 centers, 54.7% were very likely, 29.5% were less likely, and 15.8% were very unlikely to identify a MUD. Among the very unlikely and very likely groups, the survival did not differ in univariate (HR, 1.00; 95% CI, 0.82-1.21; P = .98) or multivariate analyses (HR, 1.07; 95% CI, 0.86-1.33; P = .56). Specifically, the unadjusted 1- and 2-year survival rates were 69% (95% CI, 63%-74%) vs 69% (95% CI, 66%-72%) and 56% (95% CI, 50%-62%) vs 55% (95% CI, 52%-58%), respectively.
Moreover, there was no significant difference in the risk of death between the very unlikely and very likely groups (HR, 1.07, 95% CI, 0.86-1.33; P = .56) in the covariate-adjusted Cox proportional hazard model. Age, Karnofsky performance status (KPS), disease status, and time from consent to evaluability were significantly associated with OS in the multivariate model.
A total of 70%, 66%, and 62% received a transplant in the very likely, less likely, and very unlikely groups, with median times from evaluability to transplant of 3.3 months, 3.4 months, and 3.3 months, respectively (P = .36). Furthermore, the Kaplan-Meier 2-year survival from transplant among the respective groups was 64% (95% CI, 60%-67%), 65% (95% CI, 60%-70%), and 62% (95% CI, 54%-69%; P = .70). Additionally, no significant difference in the risk of death following hematopoietic cell transplantation (HCT) was observed in the multivariate Cox model (P = .66).
“As a physician, a primary concern following a blood cancer diagnosis is getting my patient to transplant quickly, as the benefits of transplant diminish as the disease progresses. Patients can face complications, greater resistance to treatment, and worse outcomes if a prolonged search for a fully [MUD] delays transplant,” said principal study investigator Stephanie Lee, MD, MPH, professor and section head of hematologic malignancies in the Clinical Research Division at Fred Hutch Cancer Center and the David and Patricia Giuliani/Oliver Press Endowed Chair in Cancer Research, in a news release on the findings.2
The multicenter biologic assessment study did not have any requirements for age, disease status, conditioning regimen, or graft-versus-host disease (GVHD) prophylaxis, but did require patients to have diagnosed acute myeloid leukemia (AML), acute lymphocytic leukemia, myelodysplastic syndromes, non-Hodgkin lymphoma, Hodgkin lymphoma, acquired aplastic anemia, or sickle cell disease.
Those treated must have also been eligible for HCT with the intent to proceed within 6 months of enrollment, and they needed to commit to following the donor search strategy. Those ineligible for study inclusion included those who had received a prior allogenic HCT or a formal unrelated donor search.
Patients very likely or very unlikely to find a MUD had a median age at evaluability of 61.2 years (range, 0.7-81.3) vs 56.4 years (range, 2.6-76.4), were primarily male (56.3% vs 56.9%), and non-Hispanic White (88.5% vs 52.5%). In the respective groups, most had a Karnofsky score of 90 or more at evaluability (43.4% vs 50.0%), AML (51.8% vs 47.1%), and were not undergoing treatment for acute leukemia at baseline (51.4% vs 46.6%). Patients had lymphoma not responsive to treatment (76.3% vs 61.9%), and had a median time from consent to evaluability of 0.1 months (range, 0.0-12.3) vs 0.1 months (0.0-88); for most patients.
Furthermore, no differences were observed across groups for the unadjusted rates of GVHD, with cumulative 6-month grade 3 or 4 acute GVHD incidences of 11%, 12%, and 11% in the very likely, less likely, and very unlikely groups, respectively. The respective 2-year chronic GVHD rates were 39%, 33%, and 33%.
References
- Lee SJ, Logan B, Horowitz MM, et al. Primary results from Blood and Marrow Transplant Clinical Trials Network 1702: clinical transplant-related long-term outcomes of alternative donor allogeneic transplantation. J Clin Oncol. Published online September 18, 2025. doi:10.1200/JCO-25-00206
- No difference in transplant outcomes seen for patients unlikely to find a matched unrelated donor when a donor search prognosis strategy is used. News release. National Marrow Donor Program. September 19, 2025. Accessed September 25, 2025. https://tinyurl.com/2veh4n8x