Abstract

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Abstract

The new coronavirus SARS-CoV-2 has rapidly spread over the world causing the disease by WHO called COVID-19. This pandemic poses unprecedented stress on the health care system including programs performing allogeneic and autologous hematopoietic cell transplantation (HCT) and cellular therapy such as with CAR T cells. Risk factors for severe disease include age and predisposing conditions such as cancer. The true impact on stem cell transplant and CAR T-cell recipients in unknown. The European Society for Blood and Marrow Transplantation (EBMT) has therefore developed recommendations for transplant programs and physicians caring for these patients. These guidelines were developed by experts from the Infectious Diseases Working Party and have been endorsed by EBMT's scientific council and board. This work intends to provide guidelines for transplant centers, management of transplant candidates and recipients, and donor issues until the COVID-19 pandemic has passed.

Abstract

Allogeneic hematopoietic cell transplantation (alloHCT) is a complex, potentially fatal therapy featuring a myriad of complications. Triggering event(s) of such complications vary significantly, but often a so-called "multi-organ failure" (MOF) is reported as the leading cause of death. The identification of the exact trigger of MOF is critical towards early and disease-specific intervention to improve outcome. We examined data from 202 alloHCT patients reported to have died of MOF from the EBMT registry aiming to determine their exact cause of death focusing on veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) due to its life-threatening, often difficult to capture yet preventable nature. We identified a total of 70 patients (35%) for whom VOD/SOS could be considered as trigger for MOF and leading cause of death, among which 48 (69%) were previously undiagnosed. Multivariate analysis highlighted history of hepatic comorbidity or gentuzumab use and disease status beyond CR1 as the only significant factors predictive of VOD/SOS incidence (OR?=?6.6; p?=?0.001 and OR?=?3.3; p?=?0.004 respectively). VOD/SOS-related MOF was widely under-reported, accounting for 27% of deaths attributed to MOF of unknown origin without a previous VOD/SOS diagnosis. Our results suggest most missed cases developed late VOD/SOS beyond 21 days post-alloHCT, highlighting the importance of the newly revised EBMT criteria.

Abstract

We report the results of an analysis of unrelated allogeneic hematopoietic stem cell transplantations (HSCT) in 71 patients with sickle cell disease (SCD) transplanted in EBMT centers between 2005 and 2017. Median age was 9.3 years; graft type was bone marrow in 79% and peripheral blood in 21%. Recipient-donor HLA match at high resolution typing was 10/10 in 31, 9/10 in 20, and 8/10 in 4 patients; the other patients had intermediate resolution typing. The most frequent conditioning regimens were fludarabine-thiotepa-treosulfan (64%) or busulfan-cyclophosphamide (12%). Cumulative incidence of neutrophil engraftment was 92%; platelet engraftment was 90%. Eleven patients (15%) experienced graft failure. Grade II-IV acute graft-vs.-host disease (GvHD) was 23%; 3-year chronic GvHD was 23%. Three-year overall survival (OS) was 88 +/- 4%. GRFS was 62 +/- 6%. HLA matching was the most significant risk factor for OS: 3-year OS was 96 +/- 4% in 10/10 group vs. 75 +/- 10% in 9-8/10 (p = 0.042); GRFS was 69 +/- 9% vs. 50 +/- 12% (p = 0.114), respectively. In conclusion, unrelated donor HSCT is a valid option for SCD patients who lack an HLA-identical sibling donor, preferably in the context of clinical trials. Using a 10/10 HLA-matched unrelated donor yields better survival indicating that HLA matching is an important donor selection factor in this nonmalignant disease.

Abstract

Allogeneic hematopoietic stem cell transplantation (HSCT) is, to date, the only curative treatment for sickle cell disease (SCD). Because an human leukocyte antigen (HLA)-matched sibling donor is not always available, alternative stem cell sources such as unrelated or haploidentical related donors have been explored. To date, few series of SCD patients transplanted with an unrelated donor, cord blood, and haploidentical related donor have been reported, but the high rates of rejection and chronic graft versus host disease have limited their widespread application. We describe the outcomes of a retrospective, registry-based, survey on 144 alternative donor HSCT performed for SCD in 30 European Society for Blood and Marrow Transplantation centers between 1999 and 2017. Data on 70 unrelated adult donors (49%), six cord blood (4%), and 68 haploidentical donors (47%; including post-HSCT Cy, ex vivo T-cell depleted, and other haplo-HSCTs) were reported and missing information was updated by the centers. Overall, 16% patients experienced graft failure, Grade II-IV acute GVHD at 100days was 24%, whereas Grade III-IV was 10%. Chronic GVHD was observed in 24% (limited for 13 patients and extensive for 18 patients). Overall, the 3-year overall survival (OS) was 86%+/-3% and 3-year event-free survival (EFS; considering death and graft failure as events) was 72%+/-4%. We therefore conclude that alternative donor HSCT for SCD can be feasible but efforts in decreasing relapse and GVHD should be promoted to increase its safe and successful utilization. Moreover, a better knowledge of HLA matching and the tailoring of conditioning could help improve EFS and OS.

Abstract

Although most children with acute lymphoblastic leukemia (ALL) receive fractionated total body irradiation (FTBI) as myeloablative conditioning (MAC) for allogeneic hematopoietic stem cell transplantation (allo-HSCT), it is an important matter of debate if chemotherapy can effectively replace FTBI. To compare outcomes after FTBI versus chemotherapy-based conditioning (CC), we performed a retrospective EBMT registry study. Children aged 2-18 years after MAC for first allo-HSCT of bone marrow (BM) or peripheral blood stem cells (PBSC) from matched-related (MRD) or unrelated donors (UD) in first (CR1) or second remission (CR2) between 2000 and 2012 were included. Propensity score weighting was used to control pretreatment imbalances of the observed variables. 3.054 patients were analyzed. CR1 (1.498): median follow-up (FU) after FTBI (1.285) and CC (213) was 6.8 and 6.1 years. Survivals were not significantly different. CR2 (1.556): median FU after FTBI (1.345) and CC (211) was 6.2 years. Outcomes after FTBI were superior as compared with CC with regard to overall survival (OS), leukemia-free survival (LFS), relapse incidence (RI), and nonrelapse mortality (NRM). However, we must emphasize the preliminary character of the results of this retrospective "real-world-practice" study. These findings will be prospectively assessed in the ALL SCTped 2012 FORUM trial.

Abstract

PURPOSE Total body irradiation (TBI) before allogeneic hematopoietic stem cell transplantation (HSCT) in pediatric patients with acute lymphoblastic leukemia (ALL) is efficacious, but long-term side effects are concerning. We investigated whether preparative combination chemotherapy could replace TBI in such patients. PATIENTS AND METHODS FORUM is a randomized, controlled, open-label, international, multicenter, phase III, noninferiority study. Patients = 18 years at diagnosis, 4-21 years at HSCT, in complete remission pre-HSCT, and with an HLA-compatible related or unrelated donor were randomly assigned to myeloablative conditioning with fractionated 12 Gy TBI and etoposide versus fludarabine, thiotepa, and either busulfan or treosulfan. The noninferiority margin was 8%. With 1,000 patients randomly assigned in 5 years, 2-year minimum follow-up, and one-sided alpha of 5%, 80% power was calculated. A futility stopping rule would halt random assignment if chemoconditioning was significantly inferior to TBI (EudraCT: 2012-003032-22; ClinicalTrials.gov: NCT01949129). RESULTS Between April 2013 and December 2018, 543 patients were screened, 417 were randomly assigned, 212 received TBI, and 201 received chemoconditioning. The stopping rule was applied on March 31, 2019. The median follow-up was 2.1 years. In the intention-to-treat population, 2-year overall survival (OS) was significantly higher following TBI (0.91; 95% CI, 0.86 to 0.95; P < .0001) versus chemoconditioning (0.75; 95% CI, 0.67 to 0.81). Two-year cumulative incidence of relapse and treatment-related mortality were 0.12 (95% CI, 0.08 to 0.17; P < .0001) and 0.02 (95% CI, < 0.01 to 0.05; P = .0269) following TBI and 0.33 (95% CI, 0.25 to 0.40) and 0.09 (95% CI, 0.05 to 0.14) following chemoconditioning, respectively. CONCLUSION Improved OS and lower relapse risk were observed following TBI plus etoposide compared with chemoconditioning. We therefore recommend TBI plus etoposide for patients > 4 years old with high-risk ALL undergoing allogeneic HSCT.

Abstract

Severe blood disorders and cancer are the leading cause of death and disability from noncommunicable diseases in the global pediatric population and a major financial burden. The most frequent of these conditions, namely sickle cell disease and severe thalassemia, are highly curable by blood or bone marrow transplantation (BMT) which can restore a normal health-related quality of life and be cost-effective. This position paper summarizes critical issues in extending global access to BMT based on ground experience in the start-up of several BMT units in middle-income countries (MICs) across South-East Asia and the Middle East where close to 700 allogeneic BMTs have been performed over a 10-year period. Basic requirements in terms of support systems, equipment, and consumables are summarized keeping in mind WHO's model essential lists and recommendations. BMT unit setup and maintenance costs are summarized as well as those per transplant. Low-risk BMT is feasible and safe in MICs with outcomes comparable to high-income countries but at a fraction of the cost. This report might be of assistance to health care institutions in MICs interested in developing hematopoietic stem cell transplantation services and strengthening context appropriate tertiary care and higher medical education.

Abstract

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of hematopoietic cell transplantation (HCT) that is traditionally diagnosed using Baltimore or modified Seattle criteria. While Baltimore criteria require the presence of hyperbilirubinemia (bilirubin ≥2 mg/dL) for diagnosis of VOD/SOS, modified Seattle criteria do not. Prior to approval by the US Food and Drug Administration, defibrotide was available in the US through an expanded-access study (T-IND). The T-IND protocol initially required post-HCT diagnosis of VOD/SOS by Baltimore criteria or biopsy but was later amended to include patients diagnosed using modified Seattle criteria. This post-hoc analysis examined the incidence of VOD/SOS with bilirubin levels <2 mg/dL, before and after Day 21 post-HCT in T-IND patients enrolled following the amendment allowing for diagnosis by modified Seattle criteria. Survival of adult and pediatric patients with or without hyperbilirubinemia and with or without multi-organ dysfunction (MOD) was also evaluated. Of 803 post-HCT patients with VOD/SOS enrolled following the protocol amendment, 181 (23%) had bilirubin <2 mg/dL and would not have been diagnosed if hyperbilirubinemia was required. The bilirubin level at diagnosis was <2 mg/dL in 165/331 (50%) patients diagnosed by modified Seattle criteria and 16/23 (70%) patients diagnosed by biopsy. VOD/SOS with bilirubin <2 mg/dL was more common in pediatric patients (29%), although it also occurred in adult patients (15%). Patients with hyperbilirubinemia had lower Day 100 survival (54% vs 87% in patients with bilirubin <2 mg/dL) and a higher incidence of MOD (41% vs 26% in patients with bilirubin <2 mg/dL). The incidence of treatment-emergent adverse events and serious adverse events was lower in patients with bilirubin <2 mg/dL. These results indicate that anicteric VOD/SOS occurs in both adult and pediatric patients post-HCT and can be diagnosed before and after Day 21 in both groups. The worse survival in patients with bilirubin ≥2 mg/dL suggests requiring hyperbilirubinemia may result in a progressed disease stage associated with worse outcomes. Together these results highlight the importance of awareness and the possibility of VOD/SOS in the absence of elevated bilirubin levels.

Abstract

Treosulfan-based conditioning prior to allogeneic transplantation has been shown to have myeloablative, immunosuppressive, and antineoplastic effects associated with reduced non-relapse mortality (NRM) in adults. Therefore, we prospectively evaluated the safety and efficacy of treosulfan-based conditioning in children with hematological malignancies in this phase II trial. Overall, 65 children with acute lymphoblastic leukemia (35.4%), acute myeloid leukemia (44.6%), myelodysplastic syndrome (15.4%), or juvenile myelomonocytic leukemia (4.6%) received treosulfan intravenously at a dose of 10 mg/m(2)/day (7.7%), 12 g/m(2)/day (35.4%), or 14 g/m(2)/day (56.9%) according to their individual body surface area in combination with fludarabine and thiotepa. The incidence of complete donor chimerism at day +28 was 98.4% with no primary and only one secondary graft failure. At 36 months, NRM was only 3.1%, while relapse incidence was 21.7%, and overall survival was 83.0%. The cumulative incidence of acute graft-vs.-host disease was 45.3% for grades I-IV and 26.6% for grades II-IV. At 36 months, 25.8% overall and 19.4% moderate/severe chronic graft-vs.-host disease were reported. These data confirm the safe and effective use of treosulfan-based conditioning in pediatric patients with hematological malignancies. Therefore, treosulfan/fludarabine/thiotepa can be recommended for myeloablative conditioning in children with hematological malignancies.