Hematologists Highlight Top Abstracts to Watch at the 2025 EBMT Annual Meeting

Steven Devine, MD

Ahead of the 51st Annual EBMT Meeting, OncLive® asked hematology and transplant experts to share their insights on the research and presentations they are most excited to see.

We gathered exclusive perspectives from:

• Steven Devine, MD, chief medical officer at the NMDP and senior scientific director at the CIBMTR
• Everett Meyer, MD, PhD, an associate professor of medicine (blood and marrow transplantation and cellular therapy) and pediatrics (stem cell transplantation) at Stanford University and a member of the Stanford Cancer Institute in California
• Sophie Paczesny, MD, PhD, a professor in the Department of Microbiology and Immunology and co-leader of the Cancer Immunology Program at the Hollings Cancer Center at the Medical University of South Carolina in Charleston.

In the words of Dr Devine, “The EBMT Meeting is where I go to understand global cell therapy trends and how other organizations and researchers are advancing the evidence and clinical practice of transplant. I look for presentations that have the potential to advance the field and meet patient needs.”

Here are the abstracts that made these experts’ lists:

OS6-02 Targeting Cathepsin G With a Dual HLA-Restricted TCR: A Promising Therapy for Acute Myeloid Leukemia

Session time: Monday, March 31, 2:30-3:45pm CEST

Everett Meyer, MD, PhD

Meyer: Newer approaches in allogeneic transplant, such as post-transplant cyclophosphamide [PTCy] and graft engineering, have reduced graft-vs-host-disease [(GVHD) incidence], but relapse remains a problem. This single-center study is exciting because it suggests feasible ways of improving graft-vs-leukemia effects.

OS3-04: Observational Comparison of Overall Survival Between Phase 1b Orca-T And Registry-Based Post-Transplant Cyclophosphamide Patients

Session time: Monday, March 31, 2:30-3:45pm CEST

Paczesny: The phase 3 randomized study of ORCA-T [in patients undergoing allogeneic transplantation for hematologic malignancies (NCT05316701) finished accrual in June 2024, and findings were published in March 2025.] To me, the big question in the field currently is: Will the ORCA-T approach be better than post-cyclophosphamide prophylaxis, which has revolutionized the way we are doing transplant?

OS7-O3: High Accuracy of ST2 as a Risk Biomarker for Acute GVHD II-IV by Day 56 or Death by Day 100 Post-HCT in a Prospective Multisite Study

Session time: Monday, March 31, 2:30-3:45pm CEST

Sophie Paczesny, MD, PhD

Paczesny: ST2 (new name: IL1RL1) has been validated as a predictive marker of acute GVHD [aGVHD], as a risk biomarker for aGVHD, and as a prognostic marker of non-relapse mortality [NRM] in multiple large, retrospective cohorts; however its prospective qualification as a risk biomarker for [grade] II to IV aGVHD by day 56 or death by day 100 post-hematopoietic cell transplant [HCT] is not established. ST2 measured as early as day 14 post-HCT was able to risk stratify patients who will develop [grade] II to IV aGVHD, NRM, and moderate/severe chronic GVHD [cGVHD] with accuracy. The high positive predictive value [of ST2] supports the [initiation] of an interventional, biomarker-based, preemptive trial [in patients] with high risk for aGVHD and death.

GS2-4: Prevalence and Origin of Clonal Hematopoiesis in Long-Term Survivors of Pediatric Hematopoietic Cell Transplantation.

Session time: Monday, March 31, 4:30-6:00 pm CEST

Paczesny: This abstract appeals to my pediatric background. The lesson learned from this basic science abstract is that it is important to avoid peri-engraftment inflammation during pediatric HCT to keep good hematopoietic stem cells that will not transform.

OS15-01: ORCA-T Demonstrates Improved Survival Free OF Chronic GVHD Compared to Conventional Allogeneic Hematopoietic Stem Cell Transplant: A Randomized Phase 3 Trial in Advanced Hematologic Malignancies

Session time: Wednesday, April 2, 10:30-11:45am CEST

Devine: This oral presentation on an investigational allogeneic T-cell immunotherapy in a randomized, phase 3 trial [NCT05316701] represents a different precision-engineering method to minimize the risk of [experiencing] the toxic effects of cGVHD for patients with multiple types of blood cancer. Excellent results [have been achieved] using matched unrelated donors receiving the ORCA-T therapy and single-agent tacrolimus [for] GVHD prophylaxis vs a traditional calcineurin inhibitor approach with an unmanipulated graft, showing us that ingenuity is alive and well in transplant care. An observational comparison of a subset of [patients in the ORCA-T cohort] vs those in the CIBMTR database who received PTCy [OS3-04] suggests that [ORCA-T] also compares favorably with the emerging standard of care [SOC].

OS21-07: Subgroup of MDS With Very Poor-Risk Cytogenetics Harboring a More Favorable Outcome After Allogeneic Stem Cell Transplantation: A Study From the CMWP of the EBMT

Session time: Wednesday, April 2, 12:30-1:45pm CEST

Meyer: This international cohort study provides a lot of insight into the treatment of [patients with] myelodysplastic syndromes [MDS] and especially the role of allogeneic HCT with novel findings that help inform the treatment of patients.

OS20-01 Combined Kidney and Hematopoietic Cell Transplantation for Tolerance Induction Between HLA Matched Siblings

Session time: Wednesday, April 2, 12:30-1:45pm CEST

Meyer: [This trial (NCT05086003)] builds on a recent phase 3 study in the United States [US], and the cohort here appears to have [had] even better success. This likely points to a new SOC internationally and helps us think about how we might treat our many patients with cancer who also have renal failure.

OS20-08: Ultrasensitive Microchimerism Monitoring Enables Early Relapse Prediction in AML/MDS Patients: Interim Results From Acrobat Multicenter Study

Session time: Wednesday, April 2, 12:30-1:45pm CEST

Devine: Predicting early relapse from hematologic malignancies is complex, involving tumor-specific mutation monitoring, and yet the early results shown in the presentation of the multicenter ACROBAT [NCT04635384] study suggest there may be a simpler method for monitoring for early relapse using highly sensitive chimerism testing. For physicians treating patients with acute myeloid leukemia and MDS, this is a potentially promising approach that could be used across all patients regardless of the underlying mutations of their disease.

B061: Novel GVHD Prophylaxis Combining Reduced Dose Cytoxan and Abatacept Results in Low Rates Of Acute and Chronic GVHD and Low Transplant Related Toxicity

And

B049: Post-Transplant Cyclophosphamide, Abatacept, and Short Course Tacrolimus as GVHD Prophylaxis in Matched, Mismatched Unrelated Donor and Haploidentical Allogeneic Stem Cell Transplant - Mayo Clinic Experience

Printed Poster: Tuesday, April 1, 6:00-7:00pm CEST

Devine: One scientific avenue we’re advancing at NMDP in the US, and are continuing to explore globally, is improving upon the PTCy approach to further minimize GVHD and other post-transplant risks. PTCy-based strategies are already demonstrating results in mismatched unrelated donor grafts that are on par with fully matched donors—helping reimagine patient care worldwide. Exploring other novel approaches will push the field further toward safer and less toxic transplantation, expanding the potential to utilize the approach for nonmalignant indications where the risks currently outweigh the benefits. [These] 2 abstracts illustrate discovery in this area.