MINNEAPOLIS, July 9, 2025 – NMDPSM, a global nonprofit leader in cell therapy, and its collaborative research program, CIBMTR® (Center for International Blood and Marrow Transplant Research®), have released revised donor and cord blood selection guidelines to enhance transplant outcomes for patients. Published in peer-reviewed Journal of Transplantation and Cellular Therapy, the updated guidelines usher in a new era of clinical clarity and standardization around donor choice in hematopoietic cell transplantation (HCT) – enabling transplant centers and researchers access to the latest evidence-based methods for selecting suitable donors for patients who have the 75+ blood cancers and disorders for which transplant is a potential curative therapy.
"Donor selection is a highly specialized and individualized process that must account for a multitude of clinical factors, and health care providers and transplant center staff rely on published guidance around shared standards to inform complex, clinical decision-making," Antonio Martin Jimenez Jimenez, MD, first author and associate professor of medicine, Sylvester Comprehensive Cancer Center, part of the University of Miami Miller School of Medicine, said. "Transplantation science is meeting previously unmet needs across a broader range of patients than ever before, demonstrating the transformative impact of evidenced-based care."
Developed by a multidisciplinary panel of experts, the guidelines mark the first comprehensive update to the NMDP/CIBMTR guidelines since 2019 and incorporate the latest evidence-based research on donor type, human leukocyte antigen (HLA) matching and non-HLA factors that enhance patient outcomes.
Highlights of the updated guidelines include:
- Expanded donor options: Outcomes have improved for patients who undergo HCT with mismatched unrelated (MMUD) or haploidentical (haplo) donors and receive post-transplant cyclophosphamide (PTCy) for GVHD prevention. As a result, MMUD and haplo donor types should be considered early in the search process along with non-HLA factors, such as donor age.
- Search strategy: A trial from the Blood and Marrow Transplant Clinical Trials Network found that taking a patient's search prognosis score into account—such as the likelihood of an available 8/8 matched unrelated donor (MUD)—helps facilitate HCT rates and time to HCT for patients without a fully matched family member and who are less likely to find a MUD based on their HLA type and ancestry.
- Donor age: Updating previously-established research that showed a linear relationship between donor age and patient survival, the latest findings show that donors aged 18 to 30 years are associated with comparable overall survival (OS)—suggesting providers choose any viable donor in this age range to achieve the same likelihood of survival.
- HLA matching: The degree of tolerable HLA mismatch differs if calcineurin inhibitor (CNI-) or PTCy-based GVHD prevention is used. CNI requires more precise matching to minimize the risks of severe complications. In the PTCy setting, mismatches are well tolerated, but more data is needed to issue definitive guidance for prioritization of specific HLA mismatches.
"Selecting a donor is both a data-driven and emotionally charged decision, and it remains one of the most critical determinants of patient outcomes," Steven Devine, MD, chief medical officer, NMDP, senior scientific director, CIBMTR, and co-author of the study, added. "These guidelines shed new light on the rapidly-evolving transplant landscape and empower health care professionals to move faster and focus on giving patients the best chance at survival. They also improve operational efficiency for transplant centers and support care teams with guidance that reflects evidence-based science and compassion."
For help assessing the availability of 8/8 matched donors and alternative source options, NMDP offers free consultations with its search strategy experts and an online search prognosis calculator .
About CIBMTR®
CIBMTR® (Center for International Blood and Marrow Transplant Research®) is a nonprofit research collaboration between NMDPSM, in Minneapolis, and the Medical College of Wisconsin®, in Milwaukee. CIBMTR collaborates with the global scientific community to increase survival and enrich quality of life for patients. CIBMTR facilitates critical observational and interventional research through scientific and statistical expertise, a large network of centers, and a unique database of long-term clinical data for more than 675,000 people who have received hematopoietic cell transplantation and other cellular therapies. Learn more at cibmtr.org .
About NMDPSM
At NMDPSM, we believe each of us holds the key to curing blood cancers and disorders. As a global nonprofit leader in cell therapy, NMDP creates essential connections between researchers and supporters to inspire action and accelerate innovation to find life-saving cures. With the help of blood stem cell donors from the world's most diverse registry and our extensive network of transplant partners, physicians and caregivers, we're expanding access to treatment so that every patient can receive their life-saving cell therapy. NMDP. Find cures. Save lives. Learn more at nmdp.org .
