ACCESS trial results at the 2026 Tandem Meetings reinforce mismatched unrelated donors as safe, effective and well-tolerated option
Practice-advancing research conducted through CIBMTR demonstrates collaborative, ecosystem approach
MINNEAPOLIS, Feb. 04, 2026 (GLOBE NEWSWIRE) -- NMDPSM, a global nonprofit leader in cell therapy, and CIBMTR® (Center for International Blood and Marrow Transplant Research®) will present research Wednesday, Feb. 4 through Saturday, Feb. 7 at the 2026 Tandem Meetings I Transplantation & Cellular Therapy Meetings of ASTCT and CIBMTR demonstrating that patients receiving mismatched unrelated donor (MMUD) hematopoietic cell transplant (HCT) report meaningful recovery and comparable quality of life across donor match levels, among other field-changing findings. CIBMTR—a research collaboration between the Medical College of Wisconsin® and NMDP—will present findings from a total of 26 presentations, seven orals and 19 posters, demonstrating that a collaborative, ecosystem approach can advance many aspects of patient outcomes and experience.
“Our ACCESS trial and other allogeneic HCT research are advancing patient outcomes, evolving clinical practice and enabling a collaborative ecosystem to accelerate how cell therapy can serve all patients in need,” ACCESS co-chair Steven Devine, MD, chief medical officer, NMDP, and senior scientific director, CIBMTR, said.
Thriving after MMUD: Patient-reported outcomes similar across level of mismatch
Investigators in the NMDP-sponsored, CIBMTR-led ACCESS trial measured patient-reported outcomes (ID #67) and found that across results—including quality of life, physical function, fatigue and financial well-being—patients experienced similar recovery trajectories, regardless of whether they received a 7/8 or greater mismatched (4/8–6/8) donor transplant. At one-year post-transplant, patient-reported quality of life and physical function had returned to baseline, with no clinically meaningful differences observed between cohorts, and financial well-being remained stable over time.
The factor that most often impacted quality of life was whether patients developed moderate or severe chronic graft-versus-host disease (GVHD). Regardless of donor match level, patients who contracted GVHD reported worse overall quality of life, highlighting the continued importance of minimizing GVHD risk in allogeneic hematopoietic cell transplantation.
“We know that expanding donor access through MMUD does not compromise clinical outcomes, and now we have data to show that patients are not only surviving after MMUD—they feel they are returning to baseline for quality of life metrics, which are comparable to general population U.S. norms, regardless of match levels,” said Rachel Cusatis, PhD, associate professor of medicine at the Medical College of Wisconsin and CIBMTR senior scientific director of patient-centered research and survivorship. “This study also reinforces the importance of continuing to reduce complications like chronic GVHD to further improve quality of life for all patients.”
Clinical outcomes further support expanded use of <7/8 mismatched donors
Investigators will also share clinical outcomes from the ACCESS trial (ID #85) that further demonstrate patients receiving 7/8 and <7/8 unrelated donor transplants, followed by post-transplant cyclophosphamide (PTCy), can achieve strong, comparable outcomes across mismatch levels. At one-year post-transplant, overall survival (OS) exceeded 80% across all match levels, achieving a significant 86% for <7/8 mismatches and 79% for 7/8 mismatches.
In the prospective analysis of 268 patients, rates of relapse, non-relapse mortality, GVHD-free relapse-free survival and moderate-to-severe chronic GVHD were similarly favorable, demonstrating that increasing HLA mismatch did not compromise outcomes in this setting.
“For decades, exact genetic matching between donors and patients was considered critical to preventing life-threatening complications after transplant. As a pioneer in bone marrow and stem cell transplantation, City of Hope is working with leading institutions to address a longstanding challenge: the difficulty many patients face in finding a fully or closely matched donor because human leukocyte antigen (HLA) markers are inherited,” said Monzr M. Al Malki, MD, City of Hope professor, department of hematology & hematopoietic cell transplantation, and ACCESS study co-chair. “These findings suggest that now, virtually every patient searching international registries has a greater than 99% likelihood of identifying a suitable blood stem cell donor. This trial is already influencing donor selection strategies, expanding access to transplantation for patients who previously had limited or no donor options.”1
Infection burden defines the next safety frontier in MMUD transplantation
As use of MMUD transplantation grows, defining infection risk—and identifying ways to reduce it—becomes an increasing priority, given the impact on patient health and overall well-being. In a separate oral presentation (ID #111), investigators will report the first comprehensive assessment of infection burden following MMUD transplantation using standard-dose PTCy. This abstract was selected as Top 3 Infectious Diseases (ID) abstract for the 2026 Tandem Meetings.
Among patients evaluated, 68% experienced at least one grade 2 or higher infection within the first year after transplant, with infection density highest in the early post-transplant period. Infection patterns were similar between conditioning intensity strata and by degree of donor HLA mismatch, suggesting that PTCy-mediated immunosuppression may be driving infection risk.
These findings help benchmark infection risk in the standard-dose PTCy setting. Results will be used to compare new approaches, such as the reduced dose PTCy approach being evaluated on the OPTIMIZE trial, which aims to reduce post-transplant infections and while maintaining GVHD prevention for MMUD transplant recipients.
“Collaborating with our network of partners, NMDP is committed to advancing rigorous science that will allow every searching patient, regardless of ancestry, to find a potentially curative or curative treatment,” said Jeffery Auletta, MD, senior vice president, CIBMTR & Clinical Services, NMDP, and chief scientific director, CIBMTR NMDP and presenting author. “We have come a long way in ensuring more access for patients. Now, we need to optimize these treatments by minimizing risk of infection, improving overall quality of life and enabling all patients to thrive after receiving their life-saving cell therapy.”
The ACCELERATE trial, part of NMDP’s Donor for All research initiative, compares novel, reduced-dose PTCy GVHD prevention strategies against the standard dose regimen for patients undergoing MMUD HCT. ACCELERATE is expected to enroll 358 patients at up to 60 investigational centers across the U.S. Final data collection for primary outcomes is projected to conclude in 2028, with full study completion of the initial investigational arms possible by 2029.
CIBMTR oral presentations at the 2026 Tandem Meetings:
- Title: Infection Burden in Mismatched Unrelated Donor Hematopoietic Cell Transplantation Using Standard-Dose Post-Transplantation Cyclophosphamide As Graft-Versus-Host Disease Prophylaxis: Insights from the NMDP-Sponsored, CIBMTR-Led ACCESS Trial
- Presenting author: Jeffery Auletta, MD
- Session type and title: Oral Abstract – Infectious Diseases Track
- Presentation ID: 111
- Date & time: Wednesday, Feb. 4, 1:45–2 p.m. MST
- Location: Room 251 A-F (Salt Palace Convention Center)
- Title: From Clinical Trial to the Real-World: Data on Pediatric Hematopoietic Cell Transplantation for Acute Myeloid Leukemia from the Children’s Oncology Group (COG) and Center for International Blood and Marrow Transplant Research (CIBMTR)
- Presenting author: Franziska Wachter, MD
- Session type and title: Oral Abstract – Pediatric Best Abstracts
- Presentation ID: 123
- Date & time: Thursday, Feb. 5, 5–5:15 p.m. MST
- Location: Room 155 A-G (Salt Palace Convention Center)
- Title: Mismatch Doesn’t Mean Misfortune: Quality of Life after HCT in the ACCESS Trial
- Presenting author: Rachel Cusatis, PhD
- Session type and title: Oral Abstract – Session K – Improving Survivorship, Symptom Burden, and Quality of Life After Transplantation
- Presentation ID: 67
- Date & time: Friday, Feb. 6, 3:15–3:30 p.m. MST
- Location: Ballroom J (Salt Palace Convention Center)
- Title: Quality of Life and Late Effects Following Haploidentical vs. Matched Unrelated Donor Allogeneic Hematopoietic Cell Transplantation: Secondary Analysis of BMT CTN 1702
- Presenting author: Nosha Farhadfar, MD
- Session type and title: Oral Abstract – Session K – Improving Survivorship, Symptom Burden, and Quality of Life After Transplantation
- Presentation ID: 71
- Date & time: Friday, Feb. 6, 4:15-4:30 p.m. MST
- Location: Ballroom J (Salt Palace Convention Center)
- Title: Expanding Donor Access: Comparable One Year Outcomes in 4–6/8 and 7/8 Mismatched Unrelated Donor Transplantation with PTCy-Based GVHD Prophylaxis (ACCESS Trial)
- Presenting author: Monzr Al-Malki, MD
- Session type and title: Oral Abstract – Session N – Allogeneic Transplantation: Donor Biology, Immune Regulation, and GVHD Risk Reduction
- Presentation ID: 85
- Date & time: Saturday, Feb. 7, 10:30–10:45 a.m. MST
- Location: Ballroom J (Salt Palace Convention Center)
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 750,000+ 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.
Media Contact:
Jess Ayers
media@nmdp.org
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1 NMDP. Why ethnicity and diversity matter when matching. Accessed January 27, 2026. https://www.nmdp.org/get-involved/join-the-registry/ethnicity-and-diversity-matter.
