EBMT Crosses One Million Transplants as Allogeneic HCT and CAR-T Reach New Highs in European Cellular Therapy

EBMT Crosses One Million Transplants as Allogeneic HCT and CAR-T Reach New Highs in European Cellular Therapy

Section Structure

1. Highlights

2. Background and Clinical Context

3. Survey Design and Reporting Framework

4. Key Results in Hematopoietic Cell Transplantation

5. Key Results in CAR-T Cell Therapy

6. Donor, Graft Source, and Pediatric Trends

7. Clinical and Health-System Interpretation

8. Limitations and Data Considerations

9. Conclusion

10. Funding and Citation

Highlights

The 2024 EBMT activity survey passed a historic benchmark of more than one million hematopoietic cell transplants reported since 1990, underscoring the maturation of transplant medicine as a core pillar of hematology-oncology care.

In 2024, 47,204 hematopoietic cell transplants were reported in 43,791 patients across 688 centers in 53 countries. Allogeneic transplantation increased by 2.6% and reached its highest annual activity to date, while autologous transplantation declined by 3.9%.

CAR-T cell therapy continued rapid expansion, with 6,082 patients treated in 2024, a 24.5% increase versus 2023, bringing the cumulative total since 2018 above 20,000.

The report highlights resilience of European transplant and cellular therapy systems after pandemic disruption, but also points to variation in national contributions, continuing decline in cord blood use, and the need for improved monitoring of equity and age-specific access.

Background and Clinical Context

Hematopoietic cell transplantation, including both allogeneic and autologous approaches, remains central to the management of acute leukemias, myelodysplastic and myeloproliferative neoplasms, lymphomas, plasma cell disorders, bone marrow failure syndromes, inherited disorders, and selected autoimmune diseases. In parallel, chimeric antigen receptor T-cell therapy has become an increasingly important treatment platform for relapsed or refractory B-cell malignancies and multiple myeloma, with expanding investigation in additional hematologic and nonmalignant indications.

The annual activity survey conducted by the European Society for Blood and Marrow Transplantation is not a randomized trial or outcomes registry report in the traditional sense. Its major value lies in longitudinal surveillance of real-world practice: which diseases are being treated, where activity is increasing or falling, what donor sources are used, and how rapidly new cellular therapies diffuse across health systems. Such information is clinically relevant because treatment volume often reflects changing evidence, guideline adoption, reimbursement, manufacturing capacity, and referral patterns.

The 2024 report is especially notable for two reasons. First, it documents a cumulative milestone of more than one million hematopoietic cell transplants since EBMT reporting began in 1990. Second, it shows that CAR-T activity has moved beyond an early adoption phase into sustained expansion, crossing 20,000 cumulative treatments since 2018. Together, these figures mark a transition in cellular therapy from highly specialized innovation to a broad, infrastructure-dependent standard of care in many hematology settings.

Survey Design and Reporting Framework

The report summarizes annual activity data submitted by 688 centers from 53 countries. In 2024, these centers reported 47,204 hematopoietic cell transplants performed in 43,791 patients. Of these procedures, 21,023 were allogeneic and 26,181 were autologous. The survey also captured 6,082 CAR-T treatments.

As with prior EBMT activity reports, the dataset is best interpreted as a comprehensive procedural census rather than an efficacy comparison. It is designed to quantify numbers, indications, donor types, graft sources, and temporal trends. This makes it highly useful for workforce planning, donor registry coordination, manufacturing strategy, pediatric-adult resource allocation, and understanding the real-world uptake of advanced cellular therapies.

The article further notes an important methodological evolution: from 2025 onward, the EBMT survey will capture adult and pediatric activity separately. This is more than an administrative refinement. It should improve disease-specific interpretation, reveal differences in therapy diffusion by age group, and strengthen monitoring of equitable access for children and adolescents whose indications, donor options, toxicity profiles, and center organization differ substantially from those in adults.

Key Results in Hematopoietic Cell Transplantation

Total transplant activity in 2024 decreased slightly by 1.1% compared with 2023. This modest contraction, however, conceals diverging trajectories between autologous and allogeneic practice.

Allogeneic hematopoietic cell transplantation increased by 2.6%, reaching the highest annual count recorded by the survey. This rise is clinically meaningful because allogeneic transplantation is generally the more complex modality, depending on donor availability, transplant-unit capacity, infection control infrastructure, and post-transplant monitoring. Its continued growth suggests stable or recovering institutional capability despite prior pandemic-related pressures and ongoing economic constraints affecting many health systems.

By indication, myeloid malignancies remained the dominant reason for allogeneic transplantation, accounting for 62% of procedures. This category likely includes acute myeloid leukemia, myelodysplastic syndromes, myeloproliferative neoplasms, and related disorders, reflecting the continuing role of transplant in high-risk or relapsed disease and in consolidation for selected patients after remission induction. Lymphoid malignancies accounted for approximately 24% of allogeneic procedures, while non-malignant disorders represented approximately 17%. The latter proportion is a reminder that allogeneic transplantation remains indispensable in severe aplastic anemia, inherited marrow failure, hemoglobinopathies, inborn errors, and selected immunodeficiencies.

Autologous transplantation, by contrast, declined by 3.9% from 2023. Even with this decrease, autologous transplant remained numerically more common than allogeneic transplant in 2024, with 26,181 procedures. Plasma cell disorders accounted for 59% of autologous procedures, reaffirming autologous transplantation as an important component of frontline or early-line treatment in eligible multiple myeloma patients despite expanding use of monoclonal antibodies, bispecific antibodies, and CAR-T products. Lymphomas represented 22% of autologous transplants, while solid tumors accounted for approximately 6%.

The drop in autologous activity likely reflects several converging forces rather than a single cause. In lymphoma and myeloma, changing therapeutic landscapes now include highly active targeted and immune-based options that can delay, displace, or reshape the timing of transplant. In some indications, better salvage regimens may reduce the proportion of patients proceeding directly to autologous transplant. In others, evolving referral behavior and capacity constraints may contribute. The report does not establish causality, but the pattern is consistent with a field in transition rather than decline.

Key Results in CAR-T Cell Therapy

CAR-T therapy showed the most dynamic year-on-year expansion in the report. In 2024, 6,082 patients received CAR-T therapy, a 24.5% increase compared with 2023. This brought the cumulative total since 2018 to more than 20,000 patients. The scale of growth indicates that CAR-T has become integrated into routine hematology practice at an increasing number of centers, although access remains uneven.

Lymphomas continued to be the leading indication, accounting for 70% of CAR-T use. This is in line with established approvals and practice patterns in diffuse large B-cell lymphoma and related aggressive B-cell malignancies. Multiple myeloma accounted for 18% of CAR-T treatments, reflecting rapid uptake of BCMA-directed products as these therapies move from heavily pretreated populations toward earlier lines in selected settings. Acute lymphoblastic leukemia represented 8% of use, consistent with the durable but more numerically limited footprint of CAR-T in B-cell ALL.

One particularly notable finding is the 67% increase in autoimmune disease indications. Although absolute numbers are not provided in the abstract, the relative growth is striking and mirrors broader international momentum around CAR-T and related cellular strategies for refractory autoimmune disease. For clinicians and policymakers, this signal matters because it suggests that cell therapy infrastructure originally developed for hematologic malignancy may increasingly serve nononcologic disciplines, including rheumatology, neurology, and immunology. If this trend continues, future capacity planning will need to account for cross-specialty demand, new toxicity-management pathways, and reimbursement models that differ from cancer care.

At a systems level, the contrast between modestly changing transplant volumes and rapidly increasing CAR-T activity suggests that European cellular therapy is now a mixed ecosystem rather than a transplant-only enterprise. Centers, regulators, payers, and training programs will increasingly need to think in terms of an integrated cellular therapy service line that spans donor procurement, apheresis, cell engineering, conditioning, bridging therapy, ICU support, infection prevention, and survivorship.

Donor, Graft Source, and Pediatric Trends

Donor patterns in allogeneic transplantation continued to evolve. Unrelated donors accounted for 56% of allogeneic procedures and increased by 5% compared with 2023. HLA-identical sibling donors represented 25%, while haploidentical donors accounted for 19%; both categories were reported as stable. This distribution reflects the maturity of unrelated donor registries and sustained confidence in alternative-donor transplant platforms.

The increase in unrelated donor use is clinically important. It suggests that registry-based access remains robust and may still offer logistical or outcome advantages in selected settings, even in an era where haploidentical transplantation has expanded worldwide. Stable haploidentical use also implies that this approach has likely found a durable place rather than simply continuing linear expansion. In practice, donor selection is now more nuanced, incorporating disease urgency, donor age, donor-specific antibodies, CMV serostatus, graft source, center expertise, and emerging outcome data rather than relying on a single hierarchy.

Cord blood use continued its long decline, falling by 6.2%. This is consistent with trends observed over the last decade. Cord blood retains unique biologic advantages, including rapid availability and immunologic flexibility, but has lost ground to haploidentical and unrelated donor strategies because of issues such as delayed engraftment, infectious risk, and center familiarity. Its ongoing contraction raises important questions about whether cord blood should remain a niche platform for selected pediatric, inherited, or donor-limited scenarios, or whether new ex vivo expansion technologies might eventually revive its role.

Pediatric transplant activity decreased slightly overall by 1.7%, with allogeneic down 1.9% and autologous down 1.1%. The causes cannot be inferred directly from the abstract, but several possibilities deserve consideration: demographic effects, shifting indications, centralization of care, delays in referral, competition from nontransplant targeted therapies, or country-specific access barriers. The upcoming separation of adult and pediatric reporting from 2025 onward should make these trends more interpretable. That change may be particularly valuable in pediatric nonmalignant disorders, where small absolute numbers can mask clinically important shifts in access.

Clinical and Health-System Interpretation

The main message of the 2024 EBMT report is not simply that activity is large. It is that the European cellular therapy system appears resilient, adaptive, and increasingly diversified. Pandemic-era disruptions have not translated into sustained collapse. Instead, safety measures and service reorganization seem to have mitigated longer-term damage, particularly for complex allogeneic transplantation.

At the same time, the report exposes a deeper challenge: growth is not synonymous with equity. The abstract explicitly refers to variable country contributions. This likely reflects differences in national reimbursement, center accreditation, donor availability, manufacturing contracts, regulatory pathways, and workforce capacity. Such variation matters because outcomes in advanced hematology are strongly affected by timely referral and access to specialized treatment. A patient’s country or regional center should not determine whether CAR-T is available or whether unrelated donor transplantation can be pursued without delay.

For practicing clinicians, the results have several implications. First, allogeneic transplant remains highly relevant despite rapid therapeutic innovation in acute leukemia and related disorders. Second, autologous transplant volumes should be monitored carefully as they may become a sensitive indicator of how new drug classes are reshaping care pathways in myeloma and lymphoma. Third, CAR-T expansion is no longer confined to a narrow set of tertiary centers; referral networks need to adapt so that eligible patients are identified early enough to benefit. Fourth, emerging autoimmune applications may place unexpected pressure on existing cellular therapy infrastructure unless capacity expands in parallel.

For policymakers and health-system leaders, the survey reinforces the value of registry-grade activity surveillance. Procedure counts may appear descriptive, but they are foundational for estimating demand, planning staffing, forecasting bed capacity, coordinating donor registries, anticipating ICU and infectious disease support needs, and negotiating sustainable payment models for high-cost therapies. The planned age-stratified reporting from 2025 should further strengthen this function.

Limitations and Data Considerations

The report’s strengths are scale, continuity, and broad geographic representation. However, activity surveys have intrinsic limitations. They document what was done, not whether it improved survival, quality of life, or cost-effectiveness. They generally do not provide patient-level adjustment for disease risk, comorbidities, or line of therapy. As a result, increases or decreases in activity should not be interpreted as evidence of superiority or inferiority of one modality over another.

Similarly, the abstract does not provide granular country-level data, center-level concentration, manufacturing turnaround times for CAR-T, relapse outcomes, non-relapse mortality, or toxicity rates such as cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, or graft-versus-host disease. These omissions do not diminish the value of the report, but they define its proper use: surveillance and strategic interpretation, rather than comparative effectiveness analysis.

Another limitation is that aggregate disease categories can hide major shifts within subgroups. For example, “lymphomas” includes biologically and therapeutically diverse entities with very different transplant and CAR-T trajectories. Likewise, “non-malignant disorders” and “autoimmune diseases” encompass heterogeneous conditions with distinct age distributions, urgency, and treatment rationales. Future reports that link activity trends to more granular disease coding would be particularly informative.

Conclusion

The 2024 EBMT activity report captures a landmark moment in cellular therapy. More than one million hematopoietic cell transplants have now been reported since 1990, and CAR-T activity has surpassed 20,000 cumulative patients since 2018. In 2024 alone, allogeneic transplantation reached a new annual high, autologous transplantation declined modestly, and CAR-T continued rapid expansion, especially in lymphoma and myeloma, with early signals of broadening use in autoimmune disease.

The most important clinical takeaway is that cellular therapy in Europe is both expanding and changing shape. Transplant remains indispensable, particularly for myeloid malignancies and many nonmalignant disorders, while CAR-T is becoming an increasingly prominent parallel platform. The next phase for the field will require not only innovation but also better benchmarking of age-specific activity, more explicit assessment of national disparities, and stronger integration between malignant and nonmalignant cellular therapy programs.

For clinicians, researchers, and health authorities, the milestone is worth celebrating. But the more consequential challenge lies ahead: converting procedural growth into equitable, timely, and evidence-based access for all patients who may benefit.

Funding and Citation

Funding: Not stated in the provided abstract.

ClinicalTrials.gov: Not applicable. This is an activity survey report rather than an interventional registered clinical trial.

Citation: Greco R, Sánchez-Ortega I, Risitano AM, Kalwak K, Ruggeri A, Kleovoulou I, Atlija M, Alexander T, Angelucci E, Averbuch D, Bazarbachi A, Bernardo ME, Crawley C, Hazenberg MD, Penack O, Baldomero H, Passweg JR, Yakoub-Agha I, McLornan DP, Ciceri F, Sureda A. The 2024 EBMT activity report: crossing one million HCTs and 20,000 CAR-T. A landmark in cellular therapy. Bone Marrow Transplantation. 2026-05-27. PMID: 42203900. URL: https://pubmed.ncbi.nlm.nih.gov/42203900/

Related reference: Passweg JR, Baldomero H, Chabannon C, et al. Hematopoietic cell transplantation and cellular therapy survey of the EBMT: monitoring global trends and informing practice. Bone Marrow Transplantation. EBMT annual activity reports, various years. Readers should consult PubMed and the EBMT journal series for prior trend analyses and methodological context.

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