ERS/EBMT clinical practice guidelines on treatment of pulmonary chronic graft-versus-host disease in adults.

Chronic graft-versus-host disease (cGvHD) is a common complication after allogeneic haematopoietic stem cell transplantation, characterised by a broad disease spectrum that can affect virtually any organ. Although pulmonary cGvHD is a less common manifestation, it is of great concern due to its severity and poor prognosis. Optimal management of patients with pulmonary cGvHD is complicated and no standardised approach is available. The purpose of this joint European Respiratory Society (ERS) and European Society for Blood and Marrow Transplantation task force was to develop evidence-based recommendations regarding the treatment of pulmonary cGvHD phenotype bronchiolitis obliterans syndrome in adults. A multidisciplinary group representing specialists in haematology, respiratory medicine and methodology, as well as patient advocates, formulated eight PICO (patient, intervention, comparison, outcome) and two narrative questions. Following the ERS standardised methodology, we conducted systematic reviews to address these questions and used the Grading of Recommendations Assessment, Development and Evaluation approach to develop recommendations. The resulting guideline addresses common therapeutic options (inhalation therapy, fluticasone-azithromycin-montelukast, imatinib, ibrutinib, ruxolitinib, belumosudil, extracorporeal photopheresis and lung transplantation), as well as other aspects of general management, such as lung functional and radiological follow-up and pulmonary rehabilitation, for adults with pulmonary cGvHD phenotype bronchiolitis obliterans syndrome. These recommendations include important advancements that could be incorporated in the management of adults with pulmonary cGvHD, primarily aimed at improving and standardising treatment and improving outcomes.

PTCy versus ATG as graft-versus-host disease prophylaxis in mismatched unrelated stem cell transplantation.

There is an increased risk of GVHD and of non-relapse mortality (NRM) after allogeneic stem cell transplantations (alloSCT) when mismatched unrelated donors (MMUD) are used. In Europe, it is standard practice to use rabbit anti-thymocyte globulin (rATG) to reduce the high NRM and GVHD risks after MMUD alloSCT. As an alternative to rATG, post-transplantation Cyclophosphamide (PTCy) is in increasing clinical use. It is currently impossible to give general recommendations regarding preference for one method over another since comparative evidence from larger data sets is lacking. To improve the evidence base, we analyzed the outcome of rATG vs. PTCy prophylaxis in adult patients with hematologic malignancies undergoing first peripheral blood alloSCT from MMUD (9/10 antigen match) between Jan 2018 and June 2021 in the database of the European Society for Blood and Marrow Transplantation (EBMT). We performed multivariate analyses using the Cox proportional-hazards regression model. We included 2123 patients in the final analyses (PTCy, n = 583; rATG, n = 1540). p values and hazard ratios (HR) presented here are multivariate outcomes. Two years after alloSCT we found a lower NRM in the PTCy group of 18% vs. 24.9% in the rATG group; p = 0.028, HR 0.74. Overall survival in the PTCy cohort was higher with 65.7% vs. 55.7% in the rATG cohort; p < 0.001, HR 0.77. Progression-free survival was also better in the PTCy patients with 59.1% vs. 48.8% when using rATG; p = 0.001, 0.78. The incidences of chronic GVHD and acute GVHD were not significantly different between the groups. We found significantly lower NRM as well as higher survival in recipients of peripheral blood alloSCTs from MMUD receiving PTCy as compared to rATG. The results of the current analysis suggest an added value of PTCy as GVHD prophylaxis in MMUD alloSCT.

Hematopoietic cell transplantation and cellular therapies in Europe 2022. CAR-T activity continues to grow; transplant activity has slowed: a report from the EBMT.

In 2022, 46,143 HCT (19,011 (41.2%) allogeneic and 27,132 (58.8%) autologous) in 41,854 patients were reported by 689 European centers. 4329 patients received advanced cellular therapies, 3205 of which were CAR-T. An additional 2854 patients received DLI. Changes compared to the previous year were an increase in CAR-T treatments (+27%) and decrease in allogeneic (-4.0%) and autologous HCT (-1.7%). Main indications for allogeneic HCT were myeloid malignancies (10,433; 58.4%), lymphoid malignancies (4,674; 26.2%) and non-malignant disorders (2572; 14.4%). Main indications for autologous HCT were lymphomas (7897; 32.9%), PCD (13,694; 57.1%) and solid tumors (1593; 6.6%). In allogeneic HCT, use of sibling donors decreased by -7.7%, haploidentical donors by -6.3% and unrelated donors by -0.9%. Overall cord blood HCT decreased by -16.0%. Use of allogeneic, and to a lesser degree autologous HCT, decreased for lymphoid malignancies likely reflecting availability of new treatment modalities, including small molecules, bispecific antibodies, and CAR-T cells. Pediatric HCT activity remains stable (+0.3%) with differences between allogeneic and autologous HCT. Use of CAR-T continues to increase and reached a cumulative total of 9039 patients treated with wide differences across European countries. After many years of continuous growth, increase in application of HCT seems to have slowed down.

ATG or post-transplant cyclophosphamide to prevent GVHD in matched unrelated stem cell transplantation?

There is a high risk of GVHD and non-relapse mortality (NRM) after allogeneic stem cell transplantations (alloSCT) from unrelated donors. Prophylaxis with rabbit anti-thymocyte globulin (rATG) is standard in Europe but post-transplantation Cyclophosphamide (PTCy) is an emerging alternative. We analyzed outcomes of rATG (n = 7725) vs. PTCy (n = 1039) prophylaxis in adult patients with hematologic malignancies undergoing peripheral blood alloSCT from 10/10 antigen-matched unrelated donors (MUD) between January 2018 and June 2021 in the EBMT database. The provided P-values and hazard ratios (HR) are derived from multivariate analysis. Two years after alloSCT, NRM in the PTCy group was 12.1% vs. 16.4% in the rATG group; p = 0.016; HR 0.72. Relapse was less frequent after PTCy vs. rATG (22.8% vs. 26.6%; p = 0.046; HR 0.87). Overall survival after PTCy was higher (73.1% vs. 65.9%; p = 0.001, HR 0.82). Progression free survival was better after PTCy vs. rATG (64.9% vs. 57.2%; p < 0.001, HR 0.83). The incidence of chronic GVHD was lower after PTCy (28.4% vs. rATG 31.4%; p = 0.012; HR 0.77), whereas the incidence and severity of acute GVHD were not significantly different. GVHD-free relapse-free survival was significantly higher in the PTCy arm compared to the rATG arm (2 y incidence: 51% vs. 45%; HR: 0.86 [95% CI 0.75-0.99], p = 0.035). In the absence of evidence from randomized controlled trials, our findings support a preference for the use of PTCy in adult recipients of peripheral blood alloSCTs from MUD.

International recommendations for screening and preventative practices for long-term survivors of transplantation and cellular therapy: a 2023 update.

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the volume of HCT performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long-term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pre-, peri- and post-transplant exposures and other underlying risk-factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and updated in 2012. To review contemporary literature and update the recommendations while considering the changing practice of HCT and cellular therapy, an international group of experts was again convened. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed but cGVHD management is not covered in detail. These guidelines emphasize special needs of patients with distinct underlying HCT indications or comorbidities (e.g., hemoglobinopathies, older adults) but do not replace more detailed group, disease, or condition specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

International Recommendations for Screening and Preventative Practices for Long-Term Survivors of Transplantation and Cellular Therapy: A 2023 Update.

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the number of HCTs performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pretransplantation, peritransplantation, and post-transplantation exposures and other underlying risk factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and then updated in 2012. An international group of experts was convened to review the contemporary literature and update the recommendations while considering the changing practices of HCT and cellular therapy. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed, but cGVHD management is not covered in detail. These guidelines emphasize the special needs of patients with distinct underlying HCT indications or comorbidities (eg, hemoglobinopathies, older adults) but do not replace more detailed group-, disease-, or condition-specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

ECP versus ruxolitinib in steroid-refractory chronic GVHD - a retrospective study by the EBMT transplant complications working party.

Ruxolitinib has become the new standard of care for steroid-refractory and steroid-dependent chronic GVHD (SR-cGVHD). Our aim was to collect comparative data between ruxolitinib and extracorporeal photophoresis (ECP). We asked EBMT centers if they were willing to provide detailed information on GVHD grading, -therapy, -dosing, -response and complications for each included patient. 31 centers responded positively and we included all patients between 1/2017-7/2019 treated with ECP or ruxolitinib for moderate or severe SR-cGVHD. We identified 84 and 57 patients with ECP and ruxolitinib, respectively. We performed multivariate analyses adjusted on grading and type of SR-cGVHD (steroid dependent vs. refractory vs. intolerant to steroids). At day+180 after initiation of treatment for SR-cGVHD the odds ratio in the ruxolitinib group to achieve overall response vs. the ECP group was 1.35 (95% CI = [0.64; 2.91], p = 0.43). In line, we detected no statistically significant differences in overall survival, progression-free survival, non-relapse mortality and relapse incidence. The clinical significance is limited by the retrospective study design and the current data can't replace prospective studies on ECP in SR-cGVHD. However, the present results contribute to the accumulating evidence on ECP as an effective treatment option in SR-cGVHD.

Endothelial Activation and Stress Index (EASIX) to predict mortality after allogeneic stem cell transplantation: a prospective study.

BACKGROUND: We previously reported that the "Endothelial Activation and Stress Index" (EASIX; ((creatinine×lactate dehydrogenase)÷thrombocytes)) measured before start of conditioning predicts mortality after allogeneic hematopoietic stem cell transplantation (alloSCT) when used as continuous score. For broad clinical implementation, a prospectively validated EASIX-pre cut-off is needed that defines a high-risk cohort and is easy to use. METHOD: In the current study, we first performed a retrospective cohort analysis in n=2022 alloSCT recipients and identified an optimal cut-off for predicting non-relapse mortality (NRM) as EASIX-pre=3. For cut-off validation, we conducted a multicenter prospective study with inclusion of n=317 first alloSCTs from peripheral blood stem cell in adult patients with acute leukemia, lymphoma or myelodysplastic syndrome/myeloproliferative neoplasms in the European Society for Blood and Marrow Transplantation network. RESULTS: Twenty-three % (n=74) of alloSCT recipients had EASIX-pre ≥3 taken before conditioning. NRM at 2 years was 31.1% in the high EASIX group versus 11.5% in the low EASIX group (p<0.001). Patients with high EASIX-pre also had worse 2 years overall survival (51.6% vs 70.9%; p=0.002). We were able to validate the cut-off and found that EASIX ≥3 was associated with more than twofold increased risk for NRM in multivariate analysis (HR=2.18, 95% CI 1.2 to 3.94; p=0.01). No statistically significant difference could be observed for the incidence of relapse. CONCLUSIONS: The results of this study provide a prospectively validated standard laboratory biomarker index to estimate the transplant-related mortality risk after alloSCT. EASIX ≥3 taken before conditioning identifies a population of alloSCT recipients who have a more than twofold increased risk of treatment-related mortality.

Prophylaxis and management of graft-versus-host disease after stem-cell transplantation for haematological malignancies: updated consensus recommendations of the European Society for Blood and Marrow Transplantation.

Graft-versus-host disease (GVHD) is a major factor contributing to mortality and morbidity after allogeneic haematopoietic stem-cell transplantation (HSCT). In the last 3 years, there has been regulatory approval of new drugs and considerable change in clinical approaches to prophylaxis and management of GVHD. To standardise treatment approaches, the European Society for Blood and Marrow Transplantation (EBMT) has updated its clinical practice recommendations. We formed a panel of one methodologist and 22 experts in the field of GVHD management. The selection was made on the basis of their role in GVHD management in Europe and their contributions to the field, such as publications, presentations at conferences, and other research. We applied the GRADE process to ten PICO (patient, intervention, comparator, and outcome) questions: evidence was searched for by the panel and graded for each crucial outcome. In two consensus meetings, we discussed the evidence and voted on the wording and strengths of recommendations. Key updates to the recommendations include: (1) primary use of ruxolitinib in steroid-refractory acute GVHD and steroid-refractory chronic GVHD as the new standard of care, (2) use of rabbit anti-T-cell (thymocyte) globulin or post-transplantation cyclophosphamide as standard GVHD prophylaxis in peripheral blood stem-cell transplantations from unrelated donors, and (3) the addition of belumosudil to the available treatment options for steroid-refractory chronic GVHD. The EBMT proposes to use these recommendations as the basis for routine management of GVHD during allogenic HSCT. The current recommendations favour European practice and do not necessarily represent global preferences.

The impact of pre-transplantation diabetes and obesity on acute graft-versus-host disease, relapse and death after allogeneic hematopoietic cell transplantation: a study from the EBMT Transplant Complications Working Party.

Obesity and diabetes can modulate immune responses, which may impact allogeneic HCT outcomes and GvHD. From the EBMT registry, we included 36,539 adult patients who underwent allogeneic HCT for a hematological malignancy between 2016 and 2020. Of these, 5228 (14%) had obesity (BMI ≥ 30 kg/m2), 1415 (4%) had diabetes (requiring treatment with insulin or oral hypoglycemics), and 688 (2%) had obesity + diabetes pre-transplantation. Compared with patients without diabetes or obesity, the hazard ratio (HR) of grade II-IV acute GvHD was 1.00 (95% confidence interval [CI] 0.94-1.06, p = 0.89) for patients with obesity, 0.95 (CI 0.85-1.07, p = 0.43) for patients with diabetes, and 0.96 (CI 0.82-1.13, p = 0.63) for patients with obesity + diabetes. Non-relapse mortality was higher in patients with obesity (HR 1.08, CI 1.00-1.17, p = 0.047), diabetes (HR 1.40, CI 1.24-1.57, p < 0.001), and obesity + diabetes (HR 1.38, CI 1.16-1.64, p < 0.001). Overall survival after grade II-IV acute GvHD was lower in patients with diabetes (HR 1.46, CI 1.25-1.70, p < 0.001). Pre-transplantation diabetes and obesity did not influence the risk of developing acute GvHD, but pre-transplantation diabetes was associated with poorer survival after acute GvHD.

ECP versus ruxolitinib in steroid-refractory acute GVHD - a retrospective study by the EBMT transplant complications working party.

Introduction: Extracorporal Photophoresis (ECP) is in clinical use for steroid-refractory and steroid-dependent acute GVHD (SR-aGVHD). Based on recent Phase-III study results, ruxolitinib has become the new standard of care for SR-aGVHD. Our aim was to collect comparative data between ruxolitinib and ECP in SR-aGVHD in order to improve the evidence base for clinical decision making. Methods: We asked EBMT centers if they were willing to participate in this study by completing a data form (Med-C) with detailed information on GVHD grading, -therapy, -dosing, -response and complications for each included patient. Results: 31 centers responded positively (14%) and we included all patients receiving alloSCT between 1/2017-7/2019 and treated with ECP or ruxolitinib for SR-aGVHD grades II-IV from these centers. We identified 53 and 40 patients with grades II-IV SR-aGVHD who were treated with ECP and ruxolitinib, respectively. We performed multivariate analyses adjusted on grading and type of SR-aGVHD (steroid dependent vs. refractory). At day+90 after initiation of treatment for SR-aGVHD we found no statistically significant differences in overall response. The odds ratio in the ruxolitinib group to achieve overall response vs. the ECP group was 1.13 (95% CI = [0.41; 3.22], p = 0.81). In line, we detected no statistically significant differences in overall survival, progression-free survival, non-relapse mortality and relapse incidence. Discussion: The clinical significance is limited by the retrospective study design and the current data can't replace prospective studies on ECP in SR-aGVHD. However, the present results contribute to the accumulating evidence on ECP as an effective treatment option in SR-aGVHD.

Understanding the Needs and Lived Experiences of Patients With Graft-Versus-Host Disease: Real-World European Public Social Media Listening Study.

BACKGROUND: Graft-versus-host disease (GVHD) is the major cause of short- and long-term morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Treatment options beyond corticosteroid therapy remain limited, and prolonged treatment often leads to impaired quality of life (QoL). A better understanding of the needs and experiences of patients with GVHD is required to improve patient care. OBJECTIVE: The aim of this study is to explore different social media (SM) channels for gathering and analyzing the needs and experiences of patients and other stakeholders across 14 European countries. METHODS: We conducted a retrospective analysis of SM data from the public domain. The Talkwalker social analytics tool collected data from open-access forums, blogs, and various social networking sites using predefined search strings. The raw data set derived from the aggregator tool was automatically screened for the relevancy of posts, generating the curated data set that was manually reviewed to identify posts that fell within the predefined inclusion and exclusion criteria. This final data set was then used for the deep-dive analysis. RESULTS: A total of 9016 posts relating to GVHD were identified between April 2019 and April 2021. Deduplication and relevancy checks resulted in 325 insightful posts, with Twitter contributing 250 (77%) posts; blogs, 49 (15%) posts; forums, 13 (4%) posts; Facebook, 7 (2%) posts; and Instagram and YouTube, 4 (1%) posts. Patients with GVHD were the primary stakeholders, contributing 63% of all SM posts. In 234 posts, treatment was the most discussed stage of the patient journey (68%), followed by symptoms (33%), and diagnosis and tests (21%). Among treatment-related posts (n=159), steroid therapy was most frequently reported (54/159, 34%). Posts relating to treatment features (n=110) identified efficacy (45/110, 41%), side effects (38/110, 35%), and frequency and dosage (32/110, 29%), as the most frequently discussed features. Symptoms associated with GVHD were described in 24% (77/325) of posts, including skin-related conditions (49/77, 64%), dry eyes or vision change (13/77, 17%), pain and cramps (16/77, 21%), and fatigue or muscle weakness (12/77, 16%). The impacts of GVHD on QoL were discussed in 51% (165/325) of all posts, with the emotional, physical and functional, social, and financial impacts mentioned in 69% (114/165), 50% (82/165), 5% (8/165), and 2% (3/165) of these posts, respectively. Unmet needs were reported by patients or caregivers in 24% (77/325) of analyzed conversations, with treatment-related side effects being the most common (35/77, 45%) among these posts. CONCLUSIONS: SM listening is a useful tool to identify medical needs. Treatment of GVHD, including treatment-related side effects, as well as its emotional and physical impact on QoL, are the major topics that GVHD stakeholders mention on SM. We encourage a structured discussion of these topics in interactions between health care providers and patients with GVHD. TRIAL REGISTRATION: Not applicable.

Organ complications after CD19 CAR T-cell therapy for large B cell lymphoma: a retrospective study from the EBMT transplant complications and lymphoma working party.

We investigated ≥ grade 3 (CTC-AE) organ toxicities for commercial CD19 chimeric antigen receptor T cell (CAR-T cell) products in 492 patients (Axi-Cel; n = 315; Tisa-Cel; n = 177) with Large B-cell Lymphoma in the European Society for Blood and Marrow Transplantation (EBMT) CAR-T registry. The incidence of ≥ grade 3 organ toxicities during the first 100 days after CAR-T was low and the most frequent were: renal (3.0%), cardiac (2.3%), gastro-intestinal (2.3%) and hepatic (1.8%). The majority occurred within three weeks after CAR-T cell therapy. Overall survival was 83.1% [79.8-86.5; 95% CI] at 3 months and 53.5% [49-58.4; 95% CI] at one year after CAR-T. The most frequent cause of death was tumour progression (85.1%). Non-relapse mortality was 3.1% [2.3-4.1; 95% CI] at 3 months and 5.2% [4.1-6.5; 95% CI] at one year after CAR-T. The most frequent causes of non-relapse mortality were cell-therapy-related toxicities including organ toxicities (6.4% of total deaths) and infections (4.4% of total deaths). Our data demonstrates good safety in the European real-world setting.

Posttransplant cyclophosphamide versus antithymocyte globulin in patients with acute lymphoblastic leukemia treated with allogeneic hematopoietic cell transplantation from matched unrelated donors: A study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

BACKGROUND: The aim of this study was to compare two immunosuppressive strategies, based on the use of either rabbit antithymocyte globulin (ATG) or posttransplant cyclophosphamide (PTCY), as a prophylaxis of graft-versus-host disease (GVHD) for patients with acute lymphoblastic leukemia (ALL) in first complete remission who underwent hematopoietic cells transplantation from matched unrelated donors. METHODS: Overall, 117 and 779 adult patients who received PTCY and ATG, respectively, between the years 2015 and 2020 were included in this retrospective study. The median patient age was 40 and 43 years in the PTCY and ATG groups, respectively, and 37% and 35% of patients, respectively, had Philadelphia chromosome-positive ALL. RESULTS: In univariate analysis, the cumulative incidence of acute and chronic GVHD did not differ significantly between the study groups. The cumulative incidence of relapse at 2 years was reduced in the PTCY group (18% vs. 25%; p = .046) without a significant impact on nonrelapse mortality (11% vs. 16% in the ATG group; p = .29). The rates of leukemia-free survival (LFS) and overall survival were 71% versus 59%, respectively (p = .01), and 82% versus 74%, respectively (p = .08). In multivariate analysis, the receipt of ATG compared with PTCY was associated with a reduced risk of extensive chronic GVHD (hazard ratio, 0.54; 95% confidence interval, 0.3-0.98; p = .04) and an increased risk of low LFS (hazard ratio, 1.57; 95% confidence interval, 1.01-2.45; p = .045). CONCLUSIONS: The receipt of ATG compared with PTCY, despite the reduced risk of extensive chronic GVHD, is associated with inferior LFS in adults with ALL who undergo hematopoietic cell transplantation from 10/10 human leukocyte antigen-matched unrelated donors. These findings warrant verification in prospective trials.

Current incidence, severity, and management of veno-occlusive disease/sinusoidal obstruction syndrome in adult allogeneic HSCT recipients: an EBMT Transplant Complications Working Party study.

The current incidence, diagnostic policy, management, and outcome of VOD/SOS at EBMT centers were studied. All centers that had performed allogeneic HSCTs in adult patients within one defined year were invited to the study. Seventy-one centers participated with a total of 2886 allogeneic transplantations and 93 cases of VOD/SOS in 2018. The cumulative incidence of VOD/SOS at day 21 was 1.8% and at day 100 2.4%. Of 67 cases with detailed data, 52 were classical and 15 (22%) late onset (>day 21). According to the EBMT criteria, 65/67 patients had at least two VOD/SOS risk factors. The severity grades were: mild 0, moderate 3, severe 29, very severe 35. Fifty-four patients were treated with defibrotide. VOD/SOS resolved in 58% of the patients, 3/3 with moderate, 22/28 with severe, and 12/33 with very severe grade (p < 0.001). By day 100, 57% of the patients were alive; 3/3 with moderate, 22/29 with severe, and 13/35 with very severe VOD/SOS (p = 0.002). In conclusion, the incidence of VOD/SOS was low. Severe and very severe grades dominated. Very severe grade predicted poor outcome compared to severe grade further supporting the concept of early diagnosis and treatment to avoid a dismal outcome.

Immune effector cell-associated hematotoxicity: EHA/EBMT consensus grading and best practice recommendations.

Hematological toxicity is the most common adverse event after chimeric antigen receptor (CAR) T-cell therapy. Cytopenias can be profound and long-lasting and can predispose for severe infectious complications. In a recent worldwide survey, we demonstrated that there remains considerable heterogeneity in regard to current practice patterns. Here, we sought to build consensus on the grading and management of immune effector cell-associated hematotoxicity (ICAHT) after CAR T-cell therapy. For this purpose, a joint effort between the European Society for Blood and Marrow Transplantation (EBMT) and the European Hematology Association (EHA) involved an international panel of 36 CAR T-cell experts who met in a series of virtual conferences, culminating in a 2-day meeting in Lille, France. On the basis of these deliberations, best practice recommendations were developed. For the grading of ICAHT, a classification system based on depth and duration of neutropenia was developed for early (day 0-30) and late (after day +30) cytopenia. Detailed recommendations on risk factors, available preinfusion scoring systems (eg, CAR-HEMATOTOX score), and diagnostic workup are provided. A further section focuses on identifying hemophagocytosis in the context of severe hematotoxicity. Finally, we review current evidence and provide consensus recommendations for the management of ICAHT, including growth factor support, anti-infectious prophylaxis, transfusions, autologous hematopoietic stem cell boost, and allogeneic hematopoietic cell transplantation. In conclusion, we propose ICAHT as a novel toxicity category after immune effector cell therapy, provide a framework for its grading, review literature on risk factors, and outline expert recommendations for the diagnostic workup and short- and long-term management.

Total body irradiation versus busulfan based intermediate intensity conditioning for stem cell transplantation in ALL patients >45 years-a registry-based study by the Acute Leukemia Working Party of the EBMT.

Allogeneic hematopoietic cell transplantation is a potentially curative treatment in high-risk acute lymphoblastic leukemia (ALL). Conditioning regimens based on ≥12 Gray total body irradiation (TBI) represent the current standard in patients ≤45 years, whereas elderly patients frequently receive intermediate intensity conditioning (IIC) to reduce toxicity. To evaluate the role of TBI as a backbone of IIC in ALL, a retrospective, registry-based study included patients >45 years transplanted from matched donors in first complete remission, who had received either fludarabine/TBI 8 Gy (FluTBI8, n = 262), or the most popular, irradiation-free alternative fludarabine/busulfan, comprising busulfan 6.4 mg/kg (FluBu6.4, n = 188) or 9.6 mg/kg (FluBu9.6, n = 51). At two years, overall survival (OS) was 68.5%, 57%, and 62.2%, leukemia-free survival (LFS) was 58%, 42.7%, and 45%, relapse incidence (RI) was 27.2%, 40%, and 30.9%, and non-relapse-mortality (NRM) was 23.1%, 20.7%, and 26.8% for patients receiving FluTBI8Gy, FluBu6.4, and FluBu9.6, respectively. In multivariate analysis, the risk of NRM, acute and chronic graft-versus-host disease was not influenced by conditioning. However, RI was higher after FluBu6.4 (hazard ratio [HR] [95% CI]: 1.85 [1.16-2.95]), and LFS was lower after both FluBu6.4 (HR: 1.56 [1.09-2.23]) and FluBu9.6 (HR: 1.63 [1.02-2.58]) as compared to FluTBI8. Although only resulting in a non-significant advantage in OS, this observation indicates a stronger anti-leukemic efficacy of TBI-based intermediate intensity conditioning.

Decrease of lethal infectious complications in the context of causes of death (COD) after hematopoietic cell transplantation: COD-2 and COD-1 study of the Infectious Diseases Working Party EBMT.

We previously analyzed trends in incidence and factors associated with lethal complications in ALL/AML/CML patients (causes of deaths; COD-1 study). The objective of this study was the analysis of incidence and specific causes of death after HCT, with focus on infectious deaths in two time periods, 1980-2001 (cohort-1) and 2002-2015 (cohort-2). All patients with HCT for lymphoma, plasma cell disorders, chronic leukemia (except CML), myelodysplastic/myeloproliferative disorders, registered in the EBMT-ProMISe-database were included (n = 232,618) (COD-2 study). Results were compared to those in the ALL/AML/CML COD-1 study. Mortality from bacterial, viral, fungal, and parasitic infections decreased in very early, early and intermediate phases. In the late phase, mortality from bacterial infections increased, while mortality from fungal, viral, or unknown infectious etiology did not change. This pattern was similar for allo- and auto-HCT in COD-1 and COD-2 studies, with a distinct and constant lower incidence of all types of infections at all phases, after auto-HCT. In conclusion, infections were the main cause of death before day +100, followed by relapse. Mortality from infectious deaths significantly decreased, except late phase. Post-transplant mortality has significantly decreased in all phases, from all causes after auto-HCT; it has decreased in all phases after allo-HCT except late phase.

Severe cytopenia after CD19 CAR T-cell therapy: a retrospective study from the EBMT Transplant Complications Working Party.

We investigated the incidence and outcome of anti-CD19 chimeric antigen receptor (CAR) T-cells-associated Common Terminology Criteria for Adverse Events (CTCAE) ≥grade 3 cytopenia. In the EBMT CAR-T registry, we identified 398 adult patients with large B-cell lymphoma who had been treated with CAR-T-cells with axicel (62%) or tisacel (38%) before August 2021 and had cytopenia status documented for the first 100 days. Most patients had received two or three previous lines of therapy, however, 22.3% had received four or more. Disease status was progressive in 80.4%, stable in 5.0% and partial/complete remission in 14.6%. 25.9% of the patients had received a transplantation before. Median age was 61.4 years (min-max; IQR=18.7-81; (52.9-69.5)).The cumulative incidence of ≥grade 3 cytopenia was 9.0% at 30 days (95% CI (6.5 to 12.1)) and 12.1% at 100 days after CAR T-cell infusion (95% CI (9.1 to 15.5)). The median time from CAR-T infusion to cytopenia onset was 16.5 days (min-max; IQR=1-90; (4-29.8)). Grade 3 and grade 4 CTCAE cytopenia occurred in 15.2% and 84.8%, respectively. In 47.6% there was no resolution.Severe cytopenia had no significant impact on overall survival (OS) (HR 1.13 (95% CI 0.74 to 1.73), p=0.57). However, patients with severe cytopenia had a poorer progression-free survival (PFS) (HR 1.54 (95% CI 1.07 to 2.22), p=0.02) and a higher relapse incidence (HR 1.52 (95% CI 1.04 to 2.23), p=0.03). In those patients who developed severe cytopenia during the first 100 days (n=47), OS, PFS, relapse incidence and non-relapse mortality at 12 months after diagnosis of severe cytopenia were 53.6% (95% CI (40.3 to 71.2)), 20% (95% CI (10.4 to 38.6)), 73.5% (95% CI (55.2 to 85.2)) and 6.5% (95% CI (1.7 to 16.2)), respectively.In multivariate analysis of severe cytopenia risk factors, only year of CAR-T infusion (HR=0.61, 95% CI (0.39 to 0.95), p=0.028) and total number of treatment lines before CAR-T infusion (one or two lines vs three or more, HR=0.41, 95% CI (0.21 to 0.83), p=0.013) had a significant positive association with the incidence of cytopenia. Other factors, such as previous transplantation, disease status at time of CAR-T, patient age and patient sex, had no significant association.Our data provide insight on frequency and clinical relevance of severe cytopenia after CAR T-cell therapy in the European real-world setting.