Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a cornerstone in the treatment of various hematologic diseases. However, several peri-transplant challenges persist, particularly regarding the optimal timing of transplantation, the role of consolidation therapy, and maintenance strategies. At the 51st Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT 2025), the transplant team from Ruijin Hospital, Shanghai JiaoTong University School of Medicine, presented several notable studies. Among them, three studies—B254, B259, and A001—focused on comprehensive leukemia management and transplant integration, drawing significant attention from the clinical community. Hematology Frontier invited Prof. Xiaoxia Hu to provide in-depth commentary on these research findings.

Prof. Xiaoxia Hu: Our transplant team had one oral presentation and three posters accepted at this year’s EBMT Congress. Among the posters, we placed particular emphasis on the comprehensive treatment of leukemia and strategies to optimize transplant integration.

The first study (B254) focused on core binding factor acute myeloid leukemia (CBF-AML). Although CBF-AML includes two subtypes, current transplant timing strategies tend to treat them similarly. However, based on data from our retrospective and prospective cohorts, we found a clear difference in the optimal transplant timing between the CBFβ::MYH11 subtype and the more classic RUNX1::RUNX1T1 subtype. Our findings suggest that the two should be approached differently in clinical decision-making. I believe many hematologists share similar experiences in managing these two distinct subtypes.

The second study (B259) explored the clinical value of inotuzumab ozogamicin as the final consolidation therapy before allo-HSCT. Inotuzumab has shown the ability to deepen remission in patients with acute B-lymphoblastic leukemia (B-ALL). However, there remains a pressing question: which patients truly benefit from pre-transplant inotuzumab-based consolidation? Our results showed that for relapsed/refractory B-ALL patients, administering inotuzumab as the final consolidation therapy before transplantation significantly improved transplant outcomes. On the other hand, for patients who were already in first complete remission (CR1) and MRD-negative prior to transplant, inotuzumab maintenance therapy did not provide substantial additional benefit to post-transplant outcomes.

The third study (A001) addressed a question that many transplant centers continue to face: which high-risk patients benefit most from post-transplant maintenance therapy, particularly hypomethylating agents (HMAs)? While post-transplant HMA maintenance is widely adopted in clinical practice, its benefit varies. We conducted a retrospective analysis of nearly 500 transplant patients and found that HMA maintenance conferred significant benefits for patients harboring MDS-related gene mutations. However, for high-risk patients who had already achieved deep remission prior to HSCT, maintenance therapy did not lead to additional survival benefit. These findings, though retrospective, provide strong evidence to inform future prospective studies and help refine transplant strategies.

These three studies reflect the Ruijin transplant team’s ongoing efforts to personalize transplantation strategies based on disease subtype, remission status, and molecular risk, ultimately aiming to improve long-term survival and quality of life in patients with leukemia.