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International audience; Three reports address the protection of the vulnerable population of patients with hematologic malignancies in the face of the ongoing COVID pandemic. The reports suggest that some patients who fail to mount a B-cell response to vaccine may nevertheless have protective T cell responses. As a group, these reports suggest that patients should continue to be immunized with additional doses to attempt to improve immune response but that they need to maintain the precautions recommended for the unvaccinated.

International audience; BackgroundAllogeneic hematopoietic stem-cell transplantation (allo-HSCT) remains the best curative option for high-risk myelodysplastic syndrome . We retrospectively compared patient outcomes after allo-HSCT according to the intensity of the conditioning regimen.Patients and MethodsThree conditioning regimens were compared in 427 patients allografted for high-risk myelodysplastic syndrome: reduced-intensity conditioning (RIC), fludarabine (150-160 mg/m2) and busulfan (6.4 mg/kg); sequential FLAMSA-RIC, fludarabine, amsacrine, and aracytine followed by RIC; and myeloablative with reduced toxicity (RTC), fludarabine and busulfan (9.6 mg/kg or 12.8 mg/kg).ResultsThe patients in the 3 conditioning groups were different in regards to the number of treatment lines (P< .001), percentage of blasts in bone marrow (P< .001), and disease status at transplantation (P< .001). No significant differences in outcomes (overall survival, progression-free survival, nonrelapse mortality, relapse incidence, and graft versus host disease relapse-free survival) were observed between the 3 groups. Using propensity score analysis to overcome baseline imbalances, we compared 70 patients receiving FLAMSA-RIC to 260 patients receiving RIC, and compared 83 patients receiving RTC to 252 patients receiving RIC. The only factor influencing overall and progression-free survival was cytogenetic risk at transplantation. After the covariate adjustment using propensity score to reduce baseline imbalances, the only factor influencing overall and progression-free survival was still cytogenetic risk at transplantation.ConclusionOverall survival appears to be similar with the 3 conditioning regimens. The only factor influencing survival is cytogenetic risk at transplantation, suggesting that new promising drugs in the conditioning and/or early interventions after transplantation are needed to improve outcomes in these patients.

Background: Achieving a first complete remission (CR1) is an important prognostic factor for transplantation outcome. However, there are no data in the setting of cord blood transplantation (CBT) indicating whether the number of induction courses (1 or 2) needed to achieve CR1, is of prognostic significance. As CBT is advantageous for acute myelogenous leukemia (AML) patients (pts) with positive pre transplant measurable residual disease (MRD) (Milano F, NEJM 2016), it is conceivable that in the CBT setting, no difference in transplantation outcome will be observed between pts achieving CR1 after 1 or 2 inductions. Methods: Using the European Society for Blood and Marrow Transplantation (EBMT)/Acute Leukemia Working Party (ALWP) registry, we compared transplantation outcomes of adult pts aged ≥18 years with AML that underwent CBT in 2005-2020 in CR1, achieved following 1 versus (vs) 2 induction courses. Multivariate analysis (MVA) adjusting for differences between the induction groups was performed using a Cox's proportional-hazards regression model for main outcomes. Results: Three hundred and twenty-five pts were included comprising 243 (75%) with 1 and 82 (25%) with 2 induction chemotherapy courses. Median (range) follow-up was 65.4 (57.4-73.5) and 51.0 (34.8-61.5) months, respectively (p=0.6). Median age was 49.4 (19.0-70.9) and 52.1 (19.2-71.5) years (p=0.8), respectively. For patients with 1 and 2 induction courses, respectively, 49.4% and 57.3% were male, 225 (92.6%) and 78 (95.1%) pts had de novo AML, and 18 (7.4%) and 4 (4.9%) had secondary AML (p=0.6). Pts with 1 and 2 induction courses, respectively, were classified by cytogenetic risk as follows: intermediate, 62.0% and 79.2%, adverse, 33.2% and 19.5%, and favorable, 4.8% and 1.3% (p=0.02) (missing data~25%). The FLT3-ITD mutation was harbored by 33.7% and 32.3% of the pts (p=0.8), respectively (missing data ~6%). Conditioning was myeloablative (MAC) in 43.0% and 36.6% and reduced intensity (RIC) in 57.0% and 63.4%, respectively (p=0.31). Karnofsky performance score (KPS) was > 90 in 74.7% and 71% of the pts, respectively (p=0.5). The most frequent anti-graft-versus-host disease (GVHD) prophylaxis was cyclosporin A (CSA) and mycophenolate mofetil (MMF) in 75.6% and 82.5 %, or CSA with or without steroids in 16.1 % and 11.2%, respectively. Anti-thymocyte globulin (ATG) was administered to 32.9% and 25.6% of the CBT recipients, respectively (p=0.2). Engraftment rates were lower for pts achieving CR1 after 1 vs 2 induction courses (91.3% and 98.8% p=0.02) with corresponding day 60 absolute neutrophil count (ANC) > 0.5 x 10 9/L in 89.6% vs 96.3% of the pts (p=0.03). Day 180 incidence of acute GVHD grades II-IV was similar in both induction groups, 38.3% and 37.2% (p=0.8), as was 2-year total chronic GVHD, 23.4% and 27.5 %, respectively (p=0.6). In univariate analysis, the 2--year non-relapse mortality (NRM), relapse incidence (RI), leukemia-free survival (LFS), overall survival (OS) and GVHD-free, relapse-free survival (GRFS) were similar between patients achieving CR1 with 1 vs 2 induction courses with 22.6% vs 23.6% (p=0.87) 25.1% vs 30.4% (p=0.4), 52.3% vs 46.0% (p=0.3), 58.6% vs 50.0% (p=0.2), and 44% vs 44.1% (p=0.66), respectively. Similarly in MVA, there was no significant association between 2 courses of induction and NRM (hazard ratio (HR) = 1.1; 95% CI, 0.6-1.8, p=0.7), RI (HR = 1.4; 95% CI, 0.9-2.3, p=0.1), LFS (HR = 1.3; 95% CI, 0.9-1.8, p=0.2), OS (HR = 1.3; 95% CI, 0.9-1.9, p=0.1), and GRFS (HR = 1.1; 95% CI, 0.8-1.5, p=0.5). Conclusions: In CBT recipients, we did not find any significant differences in outcomes in patients achieving CR1 after one or two induction courses. Notably, engraftment was better in patients receiving two courses of induction chemotherapy. Figure 1 Figure 1. Disclosures Labopin: Jazz Pharmaceuticals: Honoraria. Forcade: Novartis: Other: travel grant. Sierra: Amgen: Other: Educational grant; Roche: Other: Educational grant; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Alexion: Other: Educational grant; Jazz Pharmaceuticals: Research Funding; Janssen: Other: Educational grant; Novartis: Honoraria, Research Funding, Speakers Bureau; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Honoraria; BMS Celgene: Honoraria, Research Funding. Byrne: Incyte: Honoraria. Blaise: Jazz Pharmaceuticals: Honoraria. Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria.

Second- and third-generation tyrosine kinase inhibitors (TKI) play an important role in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). However, data on feasibility and efficacy of using these drugs for persisting or relapsed Ph + ALL after allogeneic stem cell transplantation (alloSCT) are scarce. Based on the EBMT Acute Leukemia Working Party registry, we evaluated the use of second-/third-generation TKI in 140 patients with Ph + ALL, suffering from measurable residual disease (MRD, n = 6), molecular relapse (MRel, n = 23), or hematological relapse (HRel, n = 111) following alloSCT. Treatment included dasatinib in 104, nilotinib in 18, or ponatinib in 18 patients. Forty-nine patients received TKI monotherapy, while 91 received additional treatment. Toxicity of second-/third-generation TKI post alloSCT was comparable to pretransplant use and could be managed with dose reduction or temporary discontinuation. Response rates were 71% (overall) and 61% (following TKI monotherapy). For the entire cohort, 2- and 5-year overall survival (OS) was 49% and 33%, respectively. OS was comparable among patients treated for persisting MRD/MRel and HRel. Among patients treated with TKI monotherapy, 2- and 5-year OS was 38% and 33%, respectively. The data underscore that second-/third-generation TKI are important compounds for the management of active Ph + ALL post alloSCT.

Nocardiosis is a life-threatening opportunistic infection in immunocompromised patients. Herein, we present successful adjunctive use of liposomal nebulized amikacin and tedizolid in a recipient of allogeneic hematopoietic stem cell transplantation infected with Nocardia nova complex who presented multiple complications to conventional therapeutic options.

International audience; Background: Graft-versus-host disease (GVHD) is a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Addition of antithymocyte globulin (ATG) or post-transplantation cyclophosphamide (PTCY) to standard immunosuppressive agents reduces GVHD in different donor settings.Methods: We compared the outcomes of adults with acute myeloid leukemia undergoing allo-HSCT from HLA-identical sibling donors after the use of PTCY (n = 197) or ATG (n = 1913).Results: Patients in the PTCY group were younger than those in the ATG group (median age, 47 vs 54 years; P < .01). Peripheral blood was the most frequently used stem cell source, being significantly more frequent in the ATG group than in the PTCY group (95% vs 70% P < .01). The conditioning regimen was more frequently myeloablative in the PTCY group than in the ATG group (59% vs 48%; P < .01). Time to neutrophil engraftment was shorter in the ATG group than in the PTCY group (17 vs 20 days; P < .01). No differences were observed according to the other transplantation outcomes, except for chronic GVHD of all grades and extensive chronic GVHD at 2 years, which were significantly lower in the ATG group compared with the PTCY group (P < .02).Conclusion: PTCY is feasible in an HLA-identical sibling setting, and despite similar outcomes, ATG may be associated with lower incidence of chronic GVHD.

Double-unit unrelated cord blood transplantation (DUCBT) is an option in patients for whom a single unit is not sufficient to provide an adequate number of cells. As current guidelines on UCB unit selection are mainly based on single-unit UCB data, we performed a retrospective analysis of 1375 adult recipients of DUCBT for hematologic malignancies to determine optimal criteria for graft selection. Cryopreserved total nucleated cells (TNCs; ≤3.5 vs >3.5 × 107/kg: hazard ratio [HR], 1.53; 30% vs 45%; P = .01), number of HLA mismatches (≥2 vs 0-1: HR, 1.28; 42% vs 48%; P = .01), and ABO compatibility (minor/major ABO incompatibility vs compatibility: HR, 1.28; P = .04) were independent risk factors for OS. Cryopreserved CD34+ cell dose ≥0.7 × 105/kg in the winning UCB was associated with improved OS (HR, 1.34; P = .03). Low TNC (≤3.5 × 107/kg) and CD34+ (≤1.4 × 105/kg) cell doses were related to decreased neutrophil recovery (HR, 0.65 [P = .01] and HR, 0.81 [P = .01], respectively). DUCBT recipients with ≥2 HLA mismatches had a higher incidence of grade II-IV and III-IV acute graft-versus-host disease (HR, 1.26 [P = .03] and 1.59 [P = .02], respectively). Low TNC dose (HR, 1.57; P = .02) and receiving UCB with ≥2 HLA mismatches (HR, 1.35; P = .03) were associated with increased transplant-related mortality. Our data support selecting adequately HLA-matched UCB units with a double-unit cryopreserved TNC dose >3.5 × 107/kg and CD34+ cell dose of ≥0.7 × 105/kg per unit in DUCBT candidates.

Karyotypic analysis at time of diagnosis has an important value in determining initial response to treatment, remission duration and overall survival (OS) in acute myeloid leukemia (AML). Less is known about its value before allogeneic hematopoietic cell transplantation (allo-HCT) in patients transplanted with active disease, either relapsed or primary refractory (Rel-Ref) AML. We explored the impact of cytogenetic risk (stratification according to MRC-UK) in 2089 patients with either Ref (n = 972) or Rel AML (n = 1117) transplanted during the period 2000-2017. Overall, 154 patients had a favorable risk, 1283 had an intermediate risk and 652 had an adverse cytogenetic risk. Median follow-up was 49 months. Compared to the favorable risk group, intermediate and adverse risk patients were associated with worse leukemia-free survival and OS and also with a higher incidence of relapse. In a subgroup analysis of patients in the intermediate risk group harboring Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), this remained an important prognostic factor, being associated with worse outcomes. When analyzing patients according to the intensity of the conditioning regimen, no differences were observed for the main transplant outcomes. In conclusion, in patients diagnosed with AML and transplanted with active disease, karyotype remains an important prognostic factor, allowing splitting patients into different risk groups according to their cytogenetics. Similarly, FLT3-ITD mutation also remains a negative prognostic factor in this population.

While evidence for measurable residual disease (MRD) is a harbinger of inferior outcome in acute myeloid leukemia (AML) patients referred for allogeneic stem cell transplantation (allo-SCT), the exact clinical trajectory of specific patient subsets in this clinical setting is undefined. Using a recently published prognostic cytogenetic model (Canaani et al. Leukemia 2019) we evaluated whether this model applied also to studies of patients with positive MRD. The analysis comprised MRD+ patients in first complete remission undergoing allo-SCT from a matched sibling donor or unrelated donor. Seven hundred and seventy-five patients were evaluated with a median follow-up duration of 22 months. Cytogenetic risk score was favorable, intermediate/FLT3wt intermediate/FLT3-ITD3, and adverse in 15%, 28.3%, 37% and 19.7% of the patients, respectively. Favorable and intermediate/FLT3wt risk patients had 2-year leukemia-free survival rates of 78% and 61%, respectively, compared with only 50% and 37% for intermediate/FLT3-ITD3 and adverse risk patients, respectively (P < .001). In multivariate analysis adverse and intermediate/FLT3-ITD3 risk patients were more likely to experience disease relapse compared with favorable risk patients [hazard ratio (HR) = 3.9, 95% confidence interval (CI), 2.1-7.3; P < .001, and HR = 4.4, CI 95%, 2.4-7.8; P < .001, respectively]. The European society for blood and marrow transplantation cytogenetic risk score is a valuable adjunct for risk stratification of MRD+ AML patients.

BackgroundIn patients with acute leukemia, lymphoma and chronic malignancies, donor and/or recipient Epstein-Barr virus (EBV) seropositive status increases the risk of development of chronic graft-versus-host disease (cGVHD) after allo-hematopoietic cell transplantation (allo-HCT), while it has no influence on other transplant outcomes. No data are available on the impact of EBV serostatus on transplant outcomes in patients with nonmalignant hematological disorders.ObjectiveWe analyzed the influence of the recipient's (R) and donor's (D) EBV serostatus on transplant outcomes (overall survival (OS); relapse-free survival (RFS); relapse incidence (RI); nonrelapse mortality (NRM); acute graft-versus-host disease (aGVHD); cGVHD) in patients with nonmalignant hematological disorders undergoing allo-HCT.Patients and MethodsA total of 2,355 allo-HCTs performed between 1997 and 2016 for acquired bone marrow failure or hemoglobinopathies were included in this retrospective Registry megafile Infectious Diseases Working Party of the European Society of Blood and Marrow Transplantation (IDWP-EBMT) study.ResultsDemographics: The median age of recipient was 17.7 years (range: 0–77), and 50.8% were children. 79.0% of recipients and 75.4% of donors were EBV-seropositive. 67.8% had HCT from a matched family donor, 4.6% from a mismatched family donor, and 27.6% from an unrelated donor (UD). T-cell depletion was performed in vivo and ex vivo in 82.2% and 6.6% of patients, respectively. Conditioning regimen was myeloablative in 63.7% and reduced intensity conditioning (RIC) in 36.3% of patients. The median follow-up was 4.7 years. Transplant outcomes: EBV-seropositive recipients in comparison with EBV-seronegative recipients had lower OS (85.4% vs. 88.4%, p = 0.035) and higher NRM (10.0% vs. 6.4%, p = 0.018). No other significant differences were found for: RI, RFS, and aGVHD or cGVHD with respect to EBV pretransplant serostatus donor and/or recipient. Multivariate analysis: A trend toward higher risk of development of cGVHD (HR = 1.31; p = 0.081) and better survival (HR = 0.78; p = 0.087) in allo-HCT from EBV-seropositive donors was found. Allo-HCT in EBV-seropositive recipients had a trend toward lower risk of development of cGVHD (HR = 0.75; p = 0.065). When four subgroups (R−/D−, R−/D+, R+/D−, R+/D+ EBV serology) were analyzed, the EBV serostatus had no significant impact on OS, RFS, RI, NRM and development of aGVHD or cGVHD.ConclusionsAllo-HCT from EBV-seropositive versus EBV-seronegative donors are at 31% higher risk of cGVHD in patients with nonmalignant hematological disorders undergoing allo-HCT; however this difference is nonsignificant in multivariate analysis.

Core binding factor acute myeloid leukemia (AML) comprises two subtypes with distinct cytogenetic abnormalities of either t(8;21)(q22;q22) or inv(16)(p13q22)/t(16;16)(p13;q22). Since longterm response to chemotherapy in these leukemias is relatively good, allogeneic hematopoietic stem cell transplantation is considered in patients who relapse and achieve second complete remission. To evaluate the outcomes of allogeneic transplantation in this indication, we studied 631 patients reported to the European Society for Blood and Marrow Transplantation Registry between the years 2000 and 2014. Leukemia-free survival probabilities at two and five years were 59.1% and 54.1%, while overall survival probabilities were 65% and 58.2%, respectively. The incidence of relapse and risk of non-relapse mortality at the same time points were 19.8% and 22.5% for relapse and 20.9% and 23.3% for non-relapse mortality, respectively. The most important adverse factors influencing leukemia-free and overall survival were: leukemia with t(8;21), presence of three or more additional chromosomal abnormalities, and Karnofsky performance score

Contains fulltext : 248798.pdf (Publisher’s version ) (Open Access) Allogeneic hematopoietic cell transplantation (allo-HCT) remains a treatment option for patients with chronic myeloid leukemia (CML) who fail to respond to tyrosine kinase inhibitors (TKIs). While imatinib seems to have no adverse impact on outcomes after transplant, little is known on the effects of prior use of second-generation TKI (2GTKI). We present the results of a prospective non-interventional study performed by the EBMT on 383 consecutive CML patients previously treated with dasatinib or nilotinib undergoing allo-HCT from 2009 to 2013. The median age was 45 years (18-68). Disease status at transplant was CP1 in 139 patients (38%), AP or >CP1 in 163 (45%), and BC in 59 (16%). The choice of 2GTKI was: 40% dasatinib, 17% nilotinib, and 43% a sequential treatment of dasatinib and nilotinib with or without bosutinib/ponatinib. With a median follow-up of 37 months (1-77), 8% of patients developed either primary or secondary graft failure, 34% acute and 60% chronic GvHD. There were no differences in post-transplant complications between the three different 2GTKI subgroups. Non-relapse mortality was 18% and 24% at 12 months and at 5 years, respectively. Relapse incidence was 36%, overall survival 56% and relapse-free survival 40% at 5 years. No differences in post-transplant outcomes were found between the three different 2GTKI subgroups. This prospective study demonstrates the feasibility of allo-HCT in patients previously treated with 2GTKI with a post-transplant complications rate comparable to that of TKI-naive or imatinib-treated patients.

Item does not contain fulltext HEV infection is an emerging cause of acute and chronic hepatitis in stem cell transplant (SCT) recipients. We performed a retrospective observational study among EBMT centers with the aim of describing characteristics, management and outcome of HEV after SCT. There were 34 cases of HEV infection from 12 centers in 6 countries, diagnosed in median 4.5 months after SCT; 20 of acute and 14 of chronic infection. Non-hepatic findings possibly associated with HEV infection were present in 9 (26%). Patients with chronic infection had more characteristics associated with severely immunocompromised status. Ribavirin was provided to 16 patients (47%; 40% with acute and 57% with chronic infection), in median for 75 days. Three (19%) patients discontinued it due to side effects. HEV-RNA clearance occurred in 29 patients (85%; 85% in acute and 86% in chronic infection). HEV was considered a cause of death in 3 (9%), with 2 cases with late diagnosis. Reduction of immunosuppression in those receiving it, and ribavirin treatment in those with chronic infection were associated with shorter time to HEV-RNA clearance. Policy on HEV testing varied between the centers. In conclusion, acute and chronic HEV hepatitis should be promptly diagnosed and managed in SCT recipients.

Background: The success of unrelated haemopoietic cell transplantation (HCT) is limited by graft-versus-host disease (GVHD), which is the main post-transplantation challenge when HLA-matched donors are unavailable. A sequence dimorphism in exon 1 of HLA-B gives rise to leader peptides containing methionine (Met; M) or threonine (Thr; T), which differentially influence natural killer and T-cell alloresponses. The main aim of the study was to evaluate the role of the leader dimorphism in GVHD after HLA-B-mismatched unrelated HCT. Methods: We did a retrospective cohort study of 33 982 patients who received an unrelated HCT done in Australia, Europe, Japan, North America, and the UK between Jan 1, 1988, and Dec 31, 2016. Data were contributed by participants of the International Histocompatibility Working Group in Hematopoietic Cell Transplantation. All cases were included and there were no exclusion criteria. Multivariate regression models were used to assess risks associated with HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 mismatching. Among the 33 982 transplantations, the risks of GVHD associated with HLA-B M and T leaders were established in 17 100 (50·3%) HLA-matched and 1457 (4·3%) single HLA-B-mismatched transplantations using multivariate regression models. Leader frequencies were defined in 2 004 742 BeTheMatch US registry donors. Findings: Between Jan 20, 2017, and March 11, 2019, we assessed 33 982 HCTs using multivariate regression models for the role of HLA mismatching on outcome. Median follow-up was 1841 days (IQR 909–2963). Mortality and GVHD increased with increasing numbers of HLA mismatches. A single HLA-B mismatch increased grade 3–4 acute GVHD (odds ratio [OR] 1·89, 95% CI 1·53–2·33; p

Background : Graft failure (GF) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HCT). In the absence of autologous recovery, a second HCT is necessary to attempt preventing death due to prolonged pancytopenia. Previous studies describing outcomes of second HCT performed after a GF with different types of donor sources report a wide range of overall survival (OS) and transplant related mortality (TRM), however studies including a large number of patients receiving a second transplant with umbilical cord blood as the graft source are scarce. Objective : To describe umbilical cord blood transplants (UCBT) performed after GF following a previous HCT. Study Design : Retrospective registry-based study, using data extracted from Eurocord and the European Society for Blood and Marrow Transplantation (EBMT) databases. The study reports outcomes of 247 umbilical cord blood transplants (UCBT), performed in EBMT transplant centers, after GF following a previous HCT. Data were analyzed separately for patients with malignant (n=141) and non-malignant diseases (n=106). Results : The most frequent HCT that resulted in GF was also UCBT (65.0% and 68.9%), and most GF occurred within 100 days after transplantation (92.3% and 85.9%), for malignant and non-malignant diseases, correspondingly. Median follow-up was 47 for surviving patients with malignant and 38 months for those with non-malignant diseases. We observed a similar cumulative incidence of neutrophil engraftment of 59.1% (95% CI 51.4- 67.9%) and 60.4% (95% CI 51.7- 70.6%), in a median time of 23 and 24 days for malignant and non-malignant diseases, respectively. The 3-year OS was 28.9% (95% CI 21.8- 37.3%) in the malignant disease group and 49.1% (95% CI 39.5- 58.8%) in the non-malignant. In patients with malignancies, TRM was 39.9% (95%CI 32.5 - 49.1%) at 100 days and malignant 57.5% (95%CI 49.4 - 66.8%) at 3 years. In multivariate analyses, none of the characteristics studied were statistically significantly associated with engraftment or overall survival. Conclusion : Although survival for patients requiring a second transplant is not optimal, UCB remains a valid life-saving option for patients with GF.

We retrospectively compared outcomes of a large series of adult patients with APL in CR2 receiving alloHSCT (n = 228) or autoHSCT (n = 341) reported to the European Society for Blood and Marrow Transplantation from January 2004 to December 2018. The 2-year cumulative incidence of non-relapse mortality was significantly higher for alloHSCT 17.3% (95% CI 12.5–22.8) compared with autoHSCT 2.7% (95% CI 1.2–5) (p = 0.001), while differences in relapse rate were not significant (28% versus 22.9%; p = 0.28). Leukemia-free survival (LFS) and overall survival (OS) favored autoHSCT with 74.5% (95% CI 69–79.2) and 82.4% (95% CI 77.3–86.5) compared with alloHSCT with 54.7% (95% CI 47.5–61.3) (p = 0.001) and 64.3% (95% CI 57.2–70.6), respectively (p = 0.001 and p = 0.001). Multivariable analysis showed significantly worse LFS after alloHSCT (HR 0.49; 95% CI 0.37–0.67; p < 0.0001), older age (p = 0.001), and shorter time from diagnosis to transplant (p = 0.00015). Similar results were obtained for OS. The study shows that autoHSCT resulted in better survival outcomes (LFS and OS) for APL in CR2. These results were mainly due to reduced NRM in the autoHSCT as compared to alloHSCT.

Measurable residual disease (MRD) status pre-allogeneic hematopoietic cell transplantation (allo-HCT) has been shown to predict transplant outcomes. We investigated the effect of Anti-Thymocyte Globulin (ATG) on acute myelogenous leukemia (AML) relapse by pretransplant MRD status. AML patients undergoing allo-HCT in first complete remission from either a matched sibling or unrelated donor during the 2006–2017 period were selected. Outcomes of 1509 patients (MRD+, n = 426) were studied. ATG was used in 561 (52%) and 239 (58%) patients within the MRD− and MRD+ cohorts, respectively. In MRD− patients, ATG did not affect relapse incidence (RI) (HR = 0.80, p = 0.17), but was associated with reduced incidence of grade II–IV acute GVHD, grade II–IV and chronic GVHD, reduced nonrelapse mortality (HR = 0.66, p = 0.05), improved leukemia-free survival (HR = 0.74, p = 0.02), overall survival (HR = 0.69, p = 0.01), and GVHD-relapse free survival (HR = 0.62, p

Objectives To assess population pharmacokinetics (PK) and pharmacodynamics (PD) of both piperacillin and tazobactam in neutropenia patients and examine dosage requirements related to the MIC distribution for Gram-negative bacteria involved in bloodstream infections (BSIs). Methods We conducted a prospective study including adult haematological malignancy patients with febrile neutropenia receiving piperacillin/tazobactam as short (30 min) or prolonged (4 h) intravenous infusions. Concentration data were analysed using a population approach. Dosing simulations with the final model investigated factors influencing the PK/PD of piperacillin/tazobactam quantified by fT>MIC or PTA for piperacillin and tazobactam, respectively. In parallel, the local MIC distribution of β-lactams was documented for Gram-negative bacteria involved in BSIs. Results Over 10 months, 31 patients were enrolled, with 11 (35.5%) short and 20 (64.5%) prolonged infusion regimens. A one-compartment model adequately described the data for both drugs. Prolonged infusion, increased serum alkaline phosphatase (ALP) values and renal function impairment were associated with increased piperacillin fT>MIC. For patients with normal or augmented renal CL, dosing regimens q8h or q6h with 30 min of infusion were insufficient to achieve acceptable PTA for piperacillin/tazobactam at the median MIC value of 8 mg/L. Prolonged infusion of large doses was associated with the best PTA for both piperacillin and tazobactam. Conclusions In a population of haematological malignancy patients with neutropenia, renal function and ALP influenced the PK of piperacillin/tazobactam. Prolonged intravenous infusion would optimize the PK of piperacillin/tazobactam, especially in the case of augmented renal CL and/or low-range bacterial susceptibility.

Therapy-related acute myeloid leukemia (t-AML) arises as a late complication following antecedent solid tumors or hematologic diseases and their associated treatments. There are limited data regarding risk factors and outcomes following allogeneic hematopoietic cell transplantation (HCT) for t-AML following a prior solid tumor, and furthermore, the impact of myeloablative (MAC) vs reduced-intensity conditioning (RIC) on survival is unknown. The acute leukemia working party (ALWP) of the European society for blood and bone marrow transplantation (EBMT) performed a large registry study that included 535 patients with t-AML and prior solid tumor who underwent first MAC or RIC allogeneic HCT from 2000-2016. The primary endpoints of the study were OS and LFS. Patients receiving RIC regimens had an increase in relapse incidence (hazard ratio [HR], 1.52; 95% confidence interval [CI] 1.02-2.26; P = 0.04), lower LFS (HR, 1.52; 95% CI 1.12-2.05, P = 0.007), and OS (HR, 1.51; CI 1.09-2.09; P = 0.012). There were no differences in NRM and GRFS. Importantly, LFS and OS were superior in patients receiving ablative regimens due to a decrease in relapse. As NRM continues to decline in the current era, it is conceivable that outcomes of HCT for t-AML with prior solid tumor may be improved by careful patient selection for myeloablative regimens.

The use of antihuman T-lymphocyte immunoglobulin in the setting of transplantation from an HLA-matched related donor is still much debated. Acute and chronic graft-versus-host disease are the main causes of morbidity and mortality after allogeneic hematopoietic stem cell transplantation in patients with myelofibrosis. The aim of this study was to evaluate the effect of antihuman T-lymphocyte immunoglobulin in a large cohort of patients with myelofibrosis (n=287). The cumulative incidences of grade II-IV acute graft-versus-host disease among patients who were or were not given antihuman T-lymphocyte immunoglobulin were 26% and 41%, respectively. The corresponding incidences of chronic graft-versus-host disease were 52% and 55%, respectively. Non-adjusted overall survival, disease-free survival and non-relapse mortality rates were 55% versus 53%, 49% versus 45%, and 32% versus 31%, respectively, among the patients who were or were not given antihuman T-lymphocyte immunoglobulin. An adjusted model confirmed that the risk of acute graft-versus-host disease was lower following antihuman T-lymphocyte immunoglobulin (hazard ratio, 0.54; P=0.010) while it did not decrease the risk of chronic graft-versus-host disease. The hazard ratios for overall survival and non-relapse mortality were 0.66 and 0.64, with P-values of 0.05 and 0.09, respectively. Antihuman T-lymphocyte immunoglobulin did not influence disease-free survival, graft-versus-host disease, relapse-free survival or relapse risk. In conclusion, in the setting of matched related transplantation in myelofibrosis patients, this study demonstrates that antihuman T-lymphocyte immunoglobulin decreases the risk of acute graft-versus-host disease without increasing the risk of relapse. ispartof: HAEMATOLOGICA vol:104 issue:6 pages:1230-1236 ispartof: location:Italy status: published

Background Outcome of patients with mutation of the FLT3 tyrosine kinase domain (FLT3-TKD) in acute myeloid leukemia (AML) remains controversial. Patients and Methods Herein, we present a retrospective study of 126 newly diagnosed patients with AML performed in 2 French centers. Results FLT3-TKD mutations represented 12.7% of patients, whereas FLT3-internal tandem duplication (ITD) mutation was observed in 20.6% of AML cases and 1.6% of patients harbored both anomalies. At diagnosis, FLT3-TKD and FLT3-ITD were associated with higher peripheral leukocytes count and a higher blast count in bone marrow (P Conclusion Our data suggest that FLT3-TKD mutations should be routinely determined at the time of diagnosis. In association with NPM1 mutations, patients should follow the therapeutic schedule of favorable-risk patients with AML.

The presence of IKZF1 gene mutations is associated with poor prognosis of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The goal of this retrospective study was to evaluate outcome of allogeneic hematopoietic cell transplantation (allo-HCT) in this population. Ninety-five patients transplanted in first (n = 75) or second (n = 20) complete remission (CR) from either HLA-matched sibling (n = 32), unrelated (n = 47) or haploidentical (n = 16) donor were included in the analysis. The probabilities of the overall survival (OS) and leukemia-free survival (LFS) at 2 years were 55% and 47%, respectively. Relapse incidence (RI) was 32% while non-relapse mortality (NRM), 21%. The incidence of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD was 34% and 30%, respectively. The probability of GVHD and relapse-free survival (GRFS) was 35%. In a multivariate analysis positive minimal residual disease (MRD) status was associated with decreased chance of LFS (HR = 3.15, p = 0.004) and OS (HR = 2.37, p = 0.049) as well as increased risk of relapse (HR = 5.87, p = 0.003). Disease stage (CR2 vs. CR1) affected all, LFS, OS, GRFS, RI, and NRM. Results of allo-HCT for patients with BCP-ALL and IKZF1 mutations are generally improving, however, individuals with detectable MRD have poor prognosis and require additional intervention prior to transplantation.

Minimal residual disease (MRD) is now a powerful surrogate marker to assess the response to chemotherapy in acute myeloid leukemia (AML). DNMT3A mutation has been associated with adverse outcomes. In this study, we aimed to investigate the impact of DNMT3A status on NPM1 MRD predictive value for survival in a retrospective cohort of AML patients aged over 60 years old treated intensively. A total of 138 patients treated for NPM1-mutated AML in two French institutions were analyzed retrospectively. DNMT3A status did not influence the probability of having a ≥ 4log MRD1 reduction after induction. Only 20.4% of FLT3-ITD patients reached ≥ 4log MRD1 reduction compared to 47.5% in FLT3wt cases. A 4log reduction of NPM1 MRD was associated with a better outcome, even in FLT3-ITD mutated patients, independent of the allelic ratio. DNMT3A negative patients who reached a 4log reduction had a superior outcome to those who did not (HR = 0.23, p &lt, 0.001). However, postinduction NPM1 MRD1 reduction was not predictive of OS and LFS in DNMT3Amut patients. These results confirm that post-induction NPM1 MRD1 is a reliable tool to assess disease outcome in elderly AML patients. However, the presence of DNMT3A also identifies a subgroup of patients at high risk of relapse.

Limited data are available on legionellosis after hematopoietic stem cell transplant (HSCT). The aim of this study was to report the cases of legionellosis and to identify predictors of legionellosis, legionellosis-associated death, and non-relapse mortality (NRM). All cases of post-HSCT legionellosis from the EBMT registry were included and matched with controls in a 3:1 ratio for the analyses of risk factors. In the years 1995–2016, 80 cases from 52 centers in 14 countries were identified (mainly from France, Italy, and Spain). Median time from HSCT to legionellosis was 203 days (range, 0–4099); 19 (23.8%) patients developed early legionellosis (within-day +30 post-HSCT). Patients were mainly male (70%), after allogeneic HSCT (70%), with acute leukemia (27.5%), lymphoma (23.8%), or multiple myeloma (21.3%), and the median age of 46.6 (range, 7.2–68.2). Predictors of legionellosis were allogeneic HSCT (OR = 2.27, 95%CI:1.08–4.80, p = 0.03) and recent other infection (OR = 2.96, 95%CI:1.34–6.52, p = 0.007). Twenty-seven (33.8%) patients died due to legionellosis (44% after early legionellosis), NRM was 50%. Predictors of NRM were female sex (HR = 2.19, 95%CI:1.13–4.23, p = 0.02), early legionellosis (HR = 2.24, 95%CI:1.13–4.46, p = 0.02), and south-eastern geographical region (HR = 2.16, 95%CI:1.05–4.44, p = 0.036). In conclusion, legionellosis is a rare complication after HSCT, mainly allogeneic, occurring frequently within 30 days after HSCT and associated with high mortality.

Background Allogeneic hematopoietic cell transplantation (allo-HCT) using a mismatched unrelated donor (MMUD) and cord blood transplantation (CBT) are valid alternatives for patients without a fully human leukocyte antigen (HLA)-matched donor. Here, we compared the allo-HCT outcomes of CBT versus single-allele-mismatched MMUD allo-HCT with post-transplant cyclophosphamide (PTCy) in acute myeloid leukemia. Methods Patients who underwent a first CBT without PTCy (N = 902) or allo-HCT from a (HLA 9/10) MMUD with PTCy (N = 280) were included in the study. A multivariate regression analysis was performed for the whole population. A matched-pair analysis was carried out by propensity score-based 1:1 matching of patients (177 pairs) with known cytogenetic risk. Results The incidence of grade II–IV and grade III–IV acute graft-versus-host disease (GVHD) at 6 months was 36% versus 32% (p = 0.07) and 15% versus 11% (p = 0.16) for CBT and MMUD cohorts, respectively. CBT was associated with a higher incidence of graft failure (11% vs. 4%, p p p p = 0.05), which resulted in worse leukemia-free survival (LFS) (HR = 1.68, 95% CI 1.34–2.12, p p p p = 0.052) and chronic GVHD (p = 0.69) did not differ significantly between the cohorts. These results were confirmed in a matched-pair analysis. Conclusions CBT was associated with lower LFS, OS, and GRFS due to higher NRM, compared to MMUD allo-HCT with PTCy. In the absence of a fully matched donor, 9/10 MMUD with PTCy may be preferred over CBT.

Background Little is known about characteristics of seasonal human coronaviruses (HCoVs) (NL63, 229E, OC43, and HKU1) after allogeneic stem cell transplantation (allo-HSCT). Methods This was a collaborative Spanish and European bone marrow transplantation retrospective multicenter study, which included allo-HSCT recipients (adults and children) with upper respiratory tract disease (URTD) and/or lower respiratory tract disease (LRTD) caused by seasonal HCoV diagnosed through multiplex polymerase chain reaction assays from January 2012 to January 2019. Results We included 402 allo-HSCT recipients who developed 449 HCoV URTD/LRTD episodes. Median age of recipients was 46 years (range, 0.3–73.8 years). HCoV episodes were diagnosed at a median of 222 days after transplantation. The most common HCoV subtype was OC43 (n = 170 [38%]). LRTD involvement occurred in 121 episodes (27%). HCoV infection frequently required hospitalization (18%), oxygen administration (13%), and intensive care unit (ICU) admission (3%). Three-month overall mortality after HCoV detection was 7% in the whole cohort and 16% in those with LRTD. We identified 3 conditions associated with higher mortality in recipients with LRTD: absolute lymphocyte count Conclusions Seasonal HCoV after allo-HSCT may involve LRTD in many instances, leading to a significant morbidity.

Optimal donor choice for a second allogeneic hematopoietic cell transplant (allo-HCT) in relapsed acute lymphoblastic leukemia (ALL) remains undefined. We compared outcomes using HLA-matched unrelated donors (MUD) versus haploidentical donors in this population. Primary endpoint was overall survival (OS). The MUD allo-HCT group comprised 104 patients (male = 56, 54%), median age 36 years, mostly (76%) with B-cell phenotype in complete remission (CR) (CR2/CR3 + = 76, 73%). The 61 patients (male = 38, 62%) in the haploidentical group were younger, median age 30 years (p = 0.002), had mostly (79%) a B-cell phenotype and the majority were also in CR at time of the second allo-HCT (CR2/CR3 + = 40, 66%). Peripheral blood stem cells was the most common cell source in both, but a significantly higher number in the haploidentical group received bone marrow cells (26% vs. 4%, p < 0.0001). A haploidentical donor second allo-HCT had a 1.5-fold higher 2-year OS (49% vs. 31%), albeit not statistically significant (p = 0.13). A longer time from first allo-HCT to relapse was associated with improved OS, leukemia-free survival, graft-versus-host disease-free-relapse-free survival, and lower cumulative incidences of relapse and non-relapse mortality. Results suggest no major OS difference when choosing either a MUD or haploidentical donor for ALL patients needing a second allo-HCT.

Torque teno virus (TTV) has been proposed as a surrogate biomarker of T-cell function in allogeneic–haematopoietic–stem-cell transplantation (allo-HSCT). Conflicting data exists regarding the value of TTV to assess the degree of immunosuppression. The aim of the present study was to investigate the correlation between TTV viral load and immune function. Using samples from a prospective cohort composed of healthy-volunteers (HV) and allo-HSCT recipients at 6 months post-transplantation, we assessed the correlation between TTV viraemia and immune cell counts or T-cell proliferation capacity post-phytohaemagglutinin stimulation. TTV viraemia was detected in 68% of HV (n = 80) and 100% of allo-HSCT recipients (n = 41, p &lt, 0.001), it was significantly higher in allo-HSCT recipients (3.9 vs. 2.1 Log copies/mL, p &lt, 0.001). There was no correlation between T-cell function and CD3+T-cell count (rho: 0.002) suggesting that T-cell count can normalise without full functional recovery. Furthermore, no significant correlation was observed between TTV viraemia and absolute total/subset lymphocyte counts (rho: &lt, 0.13). The highest correlation was observed between TTV viral load and T-cell proliferation capacity (rho: −0.39). We therefore report an inverse correlation between T-cell function and TTV viraemia that is independent of T-cell count. Monitoring of TTV viraemia could be a fast suitable option to objectively assess the competence of immune function in at-risk populations.

Limited data are currently available on the outcome of patients with acute myeloid leukemia (AML) undergoing allogeneic stem cell transplantation (allo‐SCT) with a reduced performance status. We herein present the results of a registry study on 2,936 AML patients undergoing allo‐SCT in first remission (CR1) with a Karnofsky Performance Status (KPS) score less than or equal to 80%. Two‐year leukemia‐free survival (LFS), overall survival (OS) and graft‐versus‐host disease (GVHD)‐free, and relapse‐free survival (GRFS) rates were 54%, 59%, and 41%, respectively. In multivariable analysis, patients with a KPS score = 80% had lower non‐relapse mortality (NRM) and superior OS in comparison to patients with a KPS score, Graft‐versus‐host disease‐free, relapse‐free survival in patients with KPS score < 80% receiving MAC or RIC regimen.

Adult B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with t(4;11)(q21;q23);KMT2A/AFF1 is a poor-prognosis entity. This registry-based study was aimed to analyze outcome of patients with t(4;11) BCP-ALL treated with allogeneic hematopoietic stem cell transplantation (alloHSCT) in first complete remission (CR1) between 2000 and 2017, focusing on the impact of measurable residual disease (MRD) at the time of transplant. Among 151 patients (median age, 38) allotransplanted from either HLA-matched siblings or unrelated donors, leukemia-free survival (LFS) and overall survival (OS) at 2 years were 51% and 60%, whereas relapse incidence (RI) and non-relapse mortality (NRM) were 30% and 20%, respectively. These results were comparable to a cohort of contemporary patients with diploid normal karyotype (NK) BCP-ALL with equivalent inclusion criteria (n = 567). Among patients with evaluable MRD pre-alloHSCT, a negative status was the strongest beneficial factor influencing LFS (hazard ratio [HR] = 0.2, p < 0.001), OS (HR = 0.14, p < 0.001), RI (HR = 0.23, p = 0.001), and NRM (HR = 0.16, p = 0.002), with a similar outcome to MRD-negative NK BCP-ALL patients. In contrast, among patients with detectable pretransplant MRD, outcome in t(4;11) BCP-ALL was inferior to NK BCP-ALL (LFS: 27% vs. 50%, p = 0.02). These results support indication of alloHSCT in CR1 for t(4;11) BCP-ALL patients, provided a negative MRD status is achieved. Conversely, pre-alloHSCT additional therapy is warranted in MRD-positive patients.

After autologous hematopoietic cell transplantation (HCT) in the first complete remission (CR1), patients with acute myeloid leukemia (AML) may relapse and undergo allogeneic HCT in the second complete remission (CR2). The aim of this study was to analyze the outcome of allogeneic HCT performed in CR2 comparing patients with prior consolidation by autologous HCT versus patients with chemotherapy consolidation. Included were 2619 adults with allogeneic HCT in CR2 from 2000 to 2017 with (n = 417) or without (n = 2202) prior autologous HCT. Patient groups were not entirely comparable; patients with prior autologous HCT were younger, had less often a favorable cytogenetic profile, had more commonly donors other than matched siblings, and more often received reduced-intensity conditioning. In multivariate analysis, nonrelapse mortality risks in patients with prior autologous HCT were 1.34 (1.07 to 1.67; P = .01) after adjustment for age, cytogenetic risk, transplant year, donor, conditioning intensity, sex matching, interval diagnosis-relapse, and relapse-allogeneic HCT as compared with chemotherapy consolidation. Similarly, risks of events in leukemia-free survival and graft-versus-host disease, relapse-free survival were higher with prior autologous HCT, 1.17 (1.01 to 1.35), P = .03 and 1.18 (1.03 to 1.35), P = .02, respectively. Risk of death was also higher, 1.13 (0.97 to 1.32), P = .1, but this was not significant. Postremission consolidation with autologous HCT for AML in CR1 increases toxicity of subsequent allogeneic HCT in CR2.

Allogeneic hematopoietic stem cell transplantation is the only potentially curative therapy for high-risk acute myeloid leukemia. In the absence of an HLA-matched related or unrelated donor (MRD or MUD), the best alternative donor source remains controversial. Umbilical cord blood and haploidentical donors offer a time advantage when considering the duration from treatment indication to transplantation. This retrospective multicenter study of a French registry compares overall survival for alternative donor transplants in the 18 months following decision to transplant in the absence of a MRD between four groups of transplanted patients: MUD (control); HLA-mismatched MUD (mMUD); umbilical cord blood (UCB); and haploidentical (haplo). Between March 2012 and July 2016, 1302 patients were transplanted with MUD (n=803), mMUD (n=219), UCB (n=153) and haplo (n=127) donors. Multivariate analyses were conducted for overall survival 18 months after registration, overall survival after transplant, and transplant-related mortality, with adjustment for the several variables. After adjustment, the type of donor did not influence any of the three endpoints. Our results confirmed the significant negative impact of a longer time interval between registration and transplant: HR=1.04 [1.02–1.06] (p

Following chemotherapy, secondary acute myeloid leukemia (sAML), occurring after antecedent hematologic diseases, previous chemotherapy or radiation, has an inferior prognosis compared with de novo AML. To define the outcome of sAML in the context of allogeneic stem cell transplantation (alloSCT), a retrospective, registry-based comparison was performed, including 11,439 patients with de novo and 1325 with sAML. Among transplants in first complete remission (CR1) (n = 8,600), the 3-year cumulative incidence of relapse (RI) and non-relapse mortality (NRM) was 28.5% and 16.4% for de novo, and 35% and 23.4% for sAML. Three-year overall survival (OS), leukemia-free survival (LFS) and Graft-versus-Host Disease/relapse-free survival (GRFS) was 60.8%, 55.1%, and 38.6% for de novo, and 46.7%, 41.6%, and 28.4% for sAML, respectively. In multivariate analysis, sAML was associated with a lower OS (HR = 1.33 [95% CI = 1.21–1.48]; p −5), LFS (HR = 1.32 [95% CI = 1.19–1.45]; p −5) and GRFS (HR = 1.2 [95% CI = 1.1–1.31]; p −4) and higher NRM (HR = 1.37 [95% CI = 1.17–1.59]; p −4) and RI (HR = 1.27 [95% CI = 1.12–1.44]; p −3). Results of the Cox model were confirmed in a matched-pair analysis. In contrast, results did not differ between de novo and sAML after alloSCT in induction failure or relapse. Hence, this analysis identified sAML as an independent risk factor for outcome after alloSCT in CR1.

We report here the results of a retrospective study designed to evaluate outcome of patients with AML with KPS score ≤80% following allo-SCT. The analysis included adult AML patients undergoing allo-SCT in CR1 between 2000 and 2018, with a KPS score at the time of transplant between 50% and 80%. A total of 2,963 patients were identified. Median age at transplant was 55 years (18-77 years). The KPS score was 80% in 85% of the patients and On multivariate analysis, transplant from a MSD was associated with a reduced risk of aGvHD (10/10 UD HR 1.8, 9/10 UD HR 2.4, haplo HR 1.9, CB HR 3.4, p In order to compare outcome following MAC and RIC conditioning regimens the analysis was restricted to patients receiving transplant from MSD or UD. Patients with a KPS score of 80% or In conclusion, allo-SCT is feasible in patients with acute myeloid leukemia in first remission and KPS score ≤80%, with acceptable NRM and survival rates. In patients with a KPS score of 80% a MAC regimen was associated with lower relapse rate, similar NRM and better GRFS as compared to RIC, while in patients with a KPS score

International audience; Data on immunogenicity and safety of the recommended revaccination schedule against diphtheria, tetanus, poliomyelitis, pertussis, Haemophilus influenzae type b (Hib), and hepatitis B in adult allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients are limited. This prospective single-center cohort study (April 2014 to March 2018) included adult allo-HSCT recipients referred to a dedicated vaccinology consultation and vaccinated with the pediatric combined diphtheria, tetanus, acellular pertussis, hepatitis B virus, inactivated poliovirus, and Haemophilus influenzae type b (DTaP(±HB)-IPV-Hib) vaccine (3 doses 1 month apart, booster dose 1 year later). The proportion of responders to tetanus, diphtheria, Hib, and hepatitis B vaccine and geometric mean concentrations (GMCs) of antibodies were assessed before and up to 24 months after vaccination. A total of 106 patients were vaccinated at a median (interquartile range) time of 12.4 (10 to 18.4) months post-transplant. At 5.3 (4.8 to 6.6) and 23.1 (21.1 to 25.1) months after vaccine initiation, high and sustained rates of protective antibody titers were achieved for tetanus (97.8% [95% confidence interval (95% CI), 92.4% to 99.7%], n = 91/93 and 100% [95% CI, 92% to 100%], n = 44/44), diphtheria (94.6% [95% CI, 87.9% to 98.2%], n = 88/93 and 90.9% [95% CI, 78.3% to 97.5%], n = 40/44), Hib (96.6% [95% CI, 90.4% to 99.3%], n = 85/88 and 93% [95% CI, 80.9% to 98.5%], n = 40/43), and hepatitis B (83.5% [95% CI, 73.5% to 90.9%], n = 66/79 and 81.1% [95% CI, 64.8% to 92%], n = 30/37). Underlying disease, stem cell source, chronic graft-versus-host-disease, and extracorporeal photopheresis differentially influenced GMCs of tetanus, diphtheria, and hepatitis B antibodies after 3 doses but not in the long term (24 months). Six (5.7%) patients experienced mild side effects. The pediatric DTaP(±HB)-IPV-Hib vaccine was safe and effective in eliciting a sustained protective humoral response in adult allo-HSCT recipients. Hepatitis B revaccination might be optimized by using higher antigen doses.

The impact of measurable residual disease (MRD) on cord blood transplantation (CBT) outcomes has remained debated. To address this issue, we assessed the impact of measurable MRD at CBT on outcomes in large cohort of patients with acute leukemia. Inclusion criteria included adult patients with acute myeloid (AML) or acute lymphoblastic leukemia (ALL), CBT as first allo-HCT in first or second complete remission (CR) at transplantation, and known MRD status at the time of CBT. Data from 506 patients were included in the analysis. Among them, 317 patients had AML and 189 had ALL. Positive MRD was reported in 169 (33%) patients while the remaining 337 patients were MRD negative at CBT. At 2 years, relapse incidence was 18% in patients with MRD negativity vs 33% in those with MRD positivity at transplantation (P

Background: Further improvement of preparative regimens before allogeneic haemopoietic stem cell transplantation (HSCT) is an unmet medical need for the growing number of older or comorbid patients with acute myeloid leukaemia or myelodysplastic syndrome. We aimed to evaluate the efficacy and safety of conditioning with treosulfan plus fludarabine compared with reduced-intensity busulfan plus fludarabine in this population. Methods: We did an open-label, randomised, non-inferiority, phase 3 trial in 31 transplantation centres in France, Germany, Hungary, Italy, and Poland. Eligible patients were 18–70 years, had acute myeloid leukaemia in first or consecutive complete haematological remission (blast counts

Haploidentical stem cell transplantation (haploSCT) is becoming a major transplant modality for lymphoma. To assess the effects of donor characteristics, stem cell source and conditioning on outcomes, we identified 474 adults with Hodgkin (HL; 240), peripheral T-cell (PTCL; 88), diffuse large B-cell (77), mantle cell (40) or follicular lymphoma (FL; 29), who received haploSCT with post-transplant cyclophosphamide. Median follow-up of alive patients was 32 months. On multivariate analysis, acute graft-versus-host disease (GVHD) grade 2-4 was lower with offspring donors or bone marrow cells, whereas extensive chronic GVHD was higher in partial response at haploSCT or when using sisters, haploidentical donors beyond first degree, or female donors in male patients. Progression-free survival (PFS) was better for FL, HL and PTCL, whereas overall survival (OS) was better for HL and PTCL. Complete remission at haploSCT improved PFS and OS whereas these were negatively affected by cytomegalovirus donor positive/recipient positive status. No other donor characteristics (age, gender, human leucocyte antigen mismatch, ABO incompatibility) affected PFS or OS except use of haploidentical donors beyond first degree, which negatively affected OS. PFS and OS are mostly influenced by disease status and lymphoma subtype, supporting the use of any first degree haploidentical family member as a donor.

Objectives To study the management of chronic disseminated candidiasis (CDC) in patients presenting with acute leukemia. Patients and methods Single-center retrospective study of acute leukemia patients (2006–2015) to investigate three aspects of CDC: its impact on the time interval between diagnosis and hematopoietic stem cell transplantation, when required (non-parametric Wilcoxon-Mann-Whitney test); its impact on overall survival (Cox proportional hazard regression model); antifungal therapeutic strategies implemented. Results A total of 639 patients presenting with acute leukemia were included; 144 were transplanted and 29 developed CDC. CDC did not significantly increase the time interval between diagnosis and transplantation, nor did it impact the overall survival of recipients. An improved overall survival was observed in non-transplanted acute leukemia patients presenting with CDC. Conclusion CDC should not postpone transplantation if antifungal treatment is optimized.

Cytomegalovirus is one of the main contributing factors to high mortality rates in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The main factors of treatment failure are both drug resistance and intolerance. In some cases, Cytotect®CP CMV-hyperimmune globulin is used as salvage therapy. This study aims to investigate the safety and efficacy of Cytotect®CP as a salvage therapy in patients with CMV infection after allo-HCT. Twenty-three consecutive patients received Cytotect®CP for CMV infection after prior CMV therapy. At the time of Cytotect®CP introduction, 17 patients (74%) had developed acute GVHD and 15 patients (64%) were receiving steroid treatment; Cytotect®CP was used as monotherapy (n = 7) and in combination (n = 16). Overall, response was observed in 18 patients (78%) with a median time of 15 days (range: 3-51). Of the 18 responders, 4 experienced CMV reactivation, while 5 responders died within 100 days of beginning treatment. Of these 5 deaths, 4 were due to causes unrelated to CMV. Estimated 100-day OS from the introduction of Cytotect®CP was 69.6%. No statistically significant difference was observed in 100-day OS between responders and non-responders (73.7% vs 50.0%, p = 0.258). Cytotect®CP as salvage therapy is effective and well-tolerated. Given its safety profile, early treatment use should be considered.

Background: Post-transplant cyclophosphamide (PTCy) has been shown to significantly reduce transplant related mortality (TRM) post hematopoietic stem cell transplantation (HSCT) and is being increasingly used for acute myelogenous leukemia (AML) patients (pts) undergoing HSCT including from unrelated donors (UD). These publications mainly include pts transplanted in first complete remission (CR1). We recently reported outcome in 1879 AML pts transplanted in second CR (CR2) with conventional graft-versus-host disease (GVHD) prophylaxis (Leukemia 2020). Results may differ in transplantation with PTCy as GVHD prophylaxis, eliminating proliferating alloreactive T cells, and upregulating T regulatory cells while suppressing host natural killer (NK) cells immediately after transplantation, changing the biology and characteristics of the transplantation. Methods: The study aim was to assess outcome of adult AML pts, aged ≥18 years in CR2 undergoing HSCT from a 9-10/10 UD with PTCy, in 2010-2019.Statistics included multivariate analysis (MVA) adjusting for potential confounding factors was performed using a Cox's proportional-hazards regression model for main outcomes. Results: In total, 127 pts were included. Median follow-up was 19.2 (95% CI, 14.7-28) months (mos). Median age was 45.5 (range, 18.2-71.3) years. 54.3% were male. Cytogenetic risk (MRC classification) was favorable, intermediate, and adverse in 15.7%, 55.9%, and 5.5% of pts, respectively (missing data-22.8percentage) Median year of transplantation was 2017. Time from diagnosis to transplantation was 20.4 (range, 4.1-182.4) months. All pts were at CR2 at time of transplantation. Donors were 10/10 and 9/10 UD in 60.6% and 39.4% of pts, respectively. 77.8% and 47.2% of the pts and donors, respectively, were cytomegalovirus (CMV) seropositive. Conditioning was myeloablative in 50.4% and reduced intensity in 49.6%. The most frequent (61.4%) conditioning consisted of busulfan and fludarabine. All pts received PTCy as anti GVHD prophylaxis in combination with immunosuppression, which was cyclosporine A /mycophenolate mofetil (MMF) in 21.3% and MMF/tacrolimus in 23.6%. 33.9% of the pts received In vivo T-cell depletion. Grafts were peripheral blood in 93.7% and bone marrow in 6.3% of transplants. Karnofsky performance score (KPS) was > 90 in 71.2% and the hematopoietic cell transplantation-specific comorbidity index (HCT-CI) was zero in 61.5% of the pts. Engraftment was achieved by 97.6% with day (d) 60 absolute neutrophil count (ANC) > 0.5 x 10 9/L in 96.8%, and d 180 incidence of acute (a) GVHD II-IV and III-IV was 26.2% and 9.2%, respectively. The 2-year total and extensive chronic (c) GVHD was 34.3% and 13.8 %, respectively. The 2-year non-relapse mortality (NRM) was 17.2%. The 2-year relapse incidence (RI) was 21.1%. RI was the main cause of death in 41% of pts who died, followed by infections (23.1%) and GVHD (20.5%). The 2-year leukemia-free survival (LFS), overall survival (OS) and GVHD-free, relapse-free survival (GRFS) was 61.7%, 65.2% and 49.3%, respectively (Figure). In MVA time from diagnosis to transplant was significant prognostic factor for RI, LFS, OS and GRFS hazard ratio (HR) =0.19 (95% CI 0.07-0.48, p Conclusions: Outcome of AML pts undergoing HSCT from a 9-10/10 MUD in CR with PTCy as GVHD prophylaxis, are similar to previous reports using conventional GVHD prophylaxis with 26% of pts developing aGVHD ,34% cGVHD and NRM of 17%. These results are also similar to those we previously observed in pts undergoing HSCT from UD with PTCy while in CR1. Figure 1 Figure 1. Disclosures Labopin: Jazz Pharmaceuticals: Honoraria. Kulagin: X4 Pharmaceuticals, Alexion, Apellis, Biocad: Research Funding; Novartis, Generium, Sanofi, Roche, Johnson & Johnson, Pfizer: Speakers Bureau. Blaise: Jazz Pharmaceuticals: Honoraria. Yakoub-Agha: Jazz Pharmaceuticals: Honoraria. Ciceri: IRCCS Ospedale San Raffaele: Current Employment. Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria.

Introduction: Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of hematopoietic cell transplantation (HCT) conditioning that may also develop after high-dose chemotherapy. Multiorgan failure (MOF) is associated with the most severe form of VOD/SOS and, if untreated, may result in a mortality rate of >80%. Defibrotide is approved for the treatment of hepatic VOD/SOS with renal or pulmonary dysfunction post-HCT in the US and for severe hepatic VOD/SOS post-HCT in patients aged >1 month (mo) in the EU. The DEFIFrance study collected real-world data on the efficacy and safety of defibrotide from HCT centers in France. This analysis presents final, long-term data on the primary study population: patients who received defibrotide treatment for severe/very severe VOD/SOS post-HCT. Methods: This post-marketing registry study collected retrospective and prospective real-world data on patients receiving defibrotide at 53 HCT centers in France. Diagnosis of VOD/SOS was at the investigator's discretion using standard criteria, per typical clinical practice. Disease severity was categorized using adult EBMT severity criteria in patients aged ≥18 years (y), and patients aged Results: Of 798 defibrotide-treated patients enrolled in the study, 251 patients received defibrotide for the treatment of severe/very severe VOD/SOS post-HCT (severe: 117 [47%]; very severe: 134 [53%]). Median age was 45 y (range: 0, 74) and 58 (23%) patients were 50%) risk factors included prior treatment with hepatotoxic drugs (150 [60%]), iron overload (133 [58%]), and relapsed/refractory disease (137 [55%]). Risk factors of interest included prior HCT (29/239 [12%]), and prior treatment with gemtuzumab ozogamicin (17/251 [7%]) and inotuzumab ozogamicin (6/251 [2%]). At diagnosis, 55/250 (22%) patients had anicteric VOD/SOS (bilirubin levels ≤2 mg/dL). Median (range) time from VOD/SOS diagnosis to defibrotide administration was 0 (-1, 24) days. The Kaplan-Meier (KM)-estimated Day 100 post-HCT survival rate was 61% (95% confidence interval [CI]: 55%, 67%) in patients with severe/very severe VOD/SOS, with a higher survival rate seen in patients with severe versus very severe disease. The post-HCT survival rate in patients with severe/very severe VOD/SOS was 50% at 6 mo and 43% at 12 mo (Figure). KM-estimated survival rates at 6 and 12 mo were also higher for those with severe versus very severe disease (Figure). The KM-estimated CR rate by Day 100 among patients with severe/very severe VOD/SOS post-HCT was 74% (95% CI: 66%, 81%). Similar to the pattern observed for the survival rate, a higher CR rate was observed by Day 100 in patients with severe (84% [95% CI: 74, 92]) versus very severe (63% [95% CI: 52, 74]) VOD/SOS. Treatment-emergent SAEs of interest occurred in 29% of patients with severe/very severe VOD/SOS post-HCT; the most common (≥2%) treatment-emergent SAE categories were infection (17%), hemorrhage (16%), and hypotension (2%). Mortality due to VOD/SOS at 12 mo was 15%. Conclusions: The DEFIFrance study represents the largest collection of real-world data on post-registration use of defibrotide. The efficacy and safety observed in this study add to evidence from prior studies supporting the utility of defibrotide for treating patients with severe/very severe VOD/SOS post-HCT in a real-world setting. Among patients receiving defibrotide for VOD/SOS post-HCT, outcomes were better in patients with severe versus very severe VOD/SOS, highlighting the importance of early VOD/SOS diagnosis and treatment, before patients reach the most severe stage of VOD/SOS. Figure 1 Figure 1. Disclosures Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria. Blaise: Jazz Pharmaceuticals: Honoraria. Peffault De Latour: Amgen: Consultancy, Other, Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Alexion, AstraZeneca Rare Disease: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Jazz Pharmaceuticals: Honoraria. Labopin: Jazz Pharmaceuticals: Honoraria. Detrait: Jazz Pharmaceuticals: Research Funding. Huynh: Jazz Pharmaceuticals: Honoraria. Renard: Jazz Pharmaceuticals: Research Funding. Asubonteng: Jazz Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Delaval: Jazz Pharmaceuticals: Current Employment, Current equity holder in publicly-traded company. Yakoub-Agha: Jazz Pharmaceuticals: Honoraria. Dalle: Jazz Pharmaceuticals: Honoraria.

Graft failure (GF) is a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HCT). The incidence of GF after HCT using human leukocyte antigen (HLA) matched donors is lower than 5%; however, a higher incidence is observed when considering HLA mismatched donors or alternative donor sources and the use of reduced intensity conditioning (RIC) regimens. In the absence of autologous recovery, a second HCT is necessary to attempt preventing death due to prolonged pancytopenia. Previous studies describing outcomes of second HCT performed after a GF with different types of donor sources report a wide range of overall survival (OS) and transplant related mortality (TRM), however studies including a large number of patients receiving a second transplant with umbilical cord blood (UCB) are scarce. In this retrospective study, using registry data from Eurocord and the European Society for Blood and Marrow Transplantation (EBMT), we report the outcomes of 247 umbilical cord blood transplants (UCBT) performed after GF following a previous HCT. Data were analyzed separately for patients with malignant (n=141) and non-malignant diseases (n=106). UCB was the most frequent stem cell source that resulted in GF (65.0% and 68.9%, for malignant and non-malignant diseases, respectively), and most of the reported GF occurred within 100 days after HCT (92.3% and 85.9%). The most frequent diagnosis in malignant diseases was acute leukemia (64.5%), mainly acute myeloid leukemia (AML). In non-malignant diseases, the diagnoses most often reported were inborn error of metabolism (IEM) (37.7%), followed by bone marrow failure syndrome (BMF) (34.0%) and primary immune deficiency (PID) (21.7%). In malignant and non-malignant diseases, we observed a similar cumulative incidence of neutrophil engraftment of 59.1% (95% CI 51.4- 67.9%) and 60.4% (95% CI 51.7- 70.6%), in a median time of 23 and 24 days, and a 3-year OS of 28.9% (95% CI 21.8- 37.3%) and 49.1% (95% CI 39.5- 58.8%). TRM at 100 days and at 3 years for malignant diseases was 39.9% (95%CI 32.5 - 49.1%), and 57.5% (95%CI 49.4 - 66.8%). In multivariate analyses, none of the characteristics were statistically significantly associated with engraftment or overall survival. Although survival for patients requiring a second transplant is not optimal, UCB remains a valid life-saving option for some patients with GF as it is an immediately available source of stem cells in severely ill patients. The most appropriate stem cell source for salvage transplants remains controversial, as it depends on multiple factors including center choice, donor availability, underlying disease and existing comorbidities. Disclosures Peffault De Latour: Pfizer: Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Amgen: Consultancy, Other, Research Funding; Jazz Pharmaceuticals: Honoraria; Alexion, AstraZeneca Rare Disease: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding.

Patient selection becomes crucial for newly diagnosed multiple myeloma (NDMM), to identify those who may benefit the most from specific treatments. This is particularly important for patients for whom evidence of current treatment options remains very limited. One such subgroup is MM with extramedullary disease (EMD), especially those with organ manifestation. Maintenance therapy after autologous transplantation improves outcome for eligible NDMM patients, but randomized trials only included a small proportion of EMD patients, and to date, no adequate data exist on maintenance in this cohort. Here, we aimed to evaluate the characteristics and outcomes of NDMM with or without EMD after autologous transplant and maintenance therapy. Cohorts were identified from NDMM patients undergoing first autologous transplant between 2008 and 2018. Involvement had to be documented as absent or present. Maintenance treatment was defined as single-agent treatment within 6 months after first autologous transplant without relapse. Outcomes were calculated from the start of maintenance therapy. Primary end points were progression-free survival (PFS) and overall survival (OS). Secondary end point was cumulative incidence of relapse. In total, 830 NDMM patients with or without EMD were eligible, receiving either thalidomide (n=287), lenalidomide (n=446), bortezomib (n=75), or daratumumab (n=22; results for these patients will be presented at the meeting). 107 had EMD (n=83 paraskeletal and n=24 organ involvement). Maintenance drug distribution did not differ between NDMM with or without EMD (P=0.69) and is shown in Table 1. Fewer patients with organ involvement had IgA MM (23% vs 21% for no EMD and paraskeletal involvement, respectively). Patients with organ involvement more frequently were ISS stage III (50% vs 24% for no EMD and 15% for paraskeletal involvement). The median follow-up of the entire cohort was 44 months (95% CI, 40-48 months). According to involvement, 3-year PFS was 52% (48-57%) for patients without EMD, 56% (44-69%) for paraskeletal involvement, and 45% (22-68%) for organ involvement (P=0.15). Of note, early outcome after maintenance start appeared to be significantly worse for organ involvement, with 1-year PFS of 58% vs 81% for paraskeletal involvement and 82% for no EMD. 3-year OS was 81% (77-84%) for no EMD, 88% (80-96%) for paraskeletal involvement, and 68% (47-89%) for organ involvement (p=0.06). Survival curves are depicted in Figure 1. Regarding relapse, organ involvement showed worse early 1-year cumulative incidence, with 42% vs 19% for paraskeletal involvement and 16% for no EMD. In terms of maintenance therapy in patients without EMD, 3-year PFS was 45% (38-52%) for thalidomide, 59% (52-65%) for lenalidomide, 45% (31-59%) for bortezomib (P=0.005). 3-year OS was 79% (73-85%), 83% (78-88%), and 74% (61-87%; P=0.30). Relapse incidence was also significantly different showing lower relapse rates for lenalidomide (P=0.002). In terms of maintenance therapy in patients with EMD, 3-year PFS was 52% (36-67%) for thalidomide, 43% (27-60%) for lenalidomide, 65% (32-97%) for bortezomib (P=0.90). Overall survival was 81% (69-93%) for thalidomide, 86% (76-97%) for lenalidomide, and 89% (68-100%) for bortezomib (P=0.70). In multivariable analysis on PFS (including ISS, performance score, age, remission status) adjusting for early events at 1 year, organ involvement was significantly associated with worse early outcome (hazard ratio, 3.35; P=0.002) and showed no significant difference vs patients with no EMD after 1 year of follow-up. Paraskeletal involvement was not associated with different PFS. Lenalidomide was associated with significantly reduced risk for death or relapse/progression (hazard ratio, 0.69; P=0.003) vs thalidomide, and no difference was seen for bortezomib vs thalidomide. For OS, organ involvement appeared to be associated with worse outcome (hazard ratio 1.71; P=0.17), while no difference was seen for paraskeletal and no EMD. Lenalidomide (hazard ratio 0.72; P=0.05) and bortezomib (hazard ratio, 0.56; P=0.06) appeared to be associated with better OS. In conclusion, organ involvement was associated with worse early PFS, despite maintenance treatment. Different maintenance treatment did not seem to affect outcome in EMD. For patients without EMD, lenalidomide showed significantly higher PFS compared with thalidomide. Figure 1 Figure 1. Disclosures McDonald: BioCryst Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees. Kobbe: Celgene: Research Funding. Anagnostopoulos: Abbvie: Other: clinical trials; Sanofi: Other: clinical trials ; Ocopeptides: Other: clinical trials ; GSK: Other: clinical trials; Incyte: Other: clinical trials ; Takeda: Other: clinical trials ; Amgen: Other: clinical trials ; Janssen: Other: clinical trials; novartis: Other: clinical trials; Celgene: Other: clinical trials; Roche: Other: clinical trials; Astellas: Other: clinical trials . Deconinck: Stemline Therapetutics: Membership on an entity's Board of Directors or advisory committees; Imunogen: Membership on an entity's Board of Directors or advisory committees; Chugai: Research Funding; Novartis: Research Funding; Pfizer: Other: Travel Grants, Research Funding; Abbevie: Research Funding. Delforge: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees. Thurner: Takeda: Honoraria; Abbvie: Other: Travel support; Janssen: Other: Travel support; EUSA-Pharma: Honoraria, Other: Travel Support; Astra-Zeneca: Honoraria; Merck: Honoraria. Mielke: Immunicum: Other: Data safety monitoring board; DNA Prime SA: Speakers Bureau; Gilead/KITE: Other: Travel support, Expert panel ; Miltenyi: Other: Data safety monitoring board; Novartis: Speakers Bureau; Celgene/BMS: Speakers Bureau. Beksac: Amgen,Celgene,Janssen,Takeda,Oncopeptides,Sanofi: Consultancy, Speakers Bureau. Schönland: Pfizer: Honoraria; Takeda: Honoraria, Other: Travel grants; Janssen: Honoraria, Other: Travel grants, Research Funding; Prothena: Honoraria, Other: Travel grants; Sanofi: Research Funding. Yakoub-Agha: Jazz Pharmaceuticals: Honoraria.

Introduction Failure to respond to steroid therapy for intestinal acute graft-versus-host disease (aGvHD) is associated with limited further therapeutic options. Fecal microbiotherapy is defined as the perfusion of treated stool from one or several healthy donors via the upper or lower gastrointestinal (GI) route aiming at improving microbial diversity and functionality. Here we report clinical outcomes from a 76-patient cohort with steroid refractory (SR) GI-aGvHD treated with the pooled allogenic fecal microbiotherapeutic MaaT013. Twenty-four patients were treated in the prospective, single-arm, phase IIa, HERACLES study (NCT03359980) while 52 patients were treated in an expanded access program (EAP). Patients and methods For HERACLES, 24 patients with grade III-IV SR-GI-aGvHD were treated with MaaT013 in 26 European sites, as a 2 nd line therapy after SR diagnosis and evaluable for treatment response. In EAP, 52 patients with steroid-dependent or SR-GI-aGvHD (classical n=41, late onset n=3, overlap syndrome n=8) were treated. These patients had previously received and failed 1 to 6 lines (median 3; 40/52 received ruxolitinib) of GvHD systemic treatments. GI-GvHD response was evaluated weekly and 28 days after day (D) 0 (inclusion for HERACLES or 1st dose for EAP). For all patients, GI-overall response rate (ORR) at D28 was defined as the proportion of patients achieving complete response (CR), very good partial response (VGPR) or partial response (PR), compared to D0, without the use of additional systemic therapy. Other endpoints included the best overall response (BOR) achieved at any time, and overall survival (OS). Prepared under GMP, MaaT013 is characterized by a highly consistent richness of 455 ±3% OTUs and an Inverse Simpson index > 20. Treatment comprised 3 MaaT013 doses, each composed of 30 g of feces in 150 mL volume of inoculum (total 90 g of feces from 4 to 8 healthy donors) administered by enema (except for 2 EAP patients by nasogastric tube). All patients received at least 1 MaaT013 dose, 92% (HERACLES) and 87% (EAP) at least 2 doses, and 50% (HERACLES) and 71% (EAP) the full treatment course. In HERACLES, the reasons for not applying the 3 rd dose were death (n=5), physician decision to introduce salvage therapy (n=5), and ICU hospitalization (n=2)). Results In HERACLES, the GI-ORR was 38% including 5 CR, 2 VGPR and 2 PR. In EAP, positive GI-response was achieved in 31/52 patients (60% with 16 CR, 11 VGPR and 4 PR). Considering the GI-BOR, 13/24 (54%) and 35/52 (67%) achieved at least a PR in HERACLES and EAP respectively. In HERACLES, OS was 29% at month (M) 6 and 25% at M12. OS was significantly higher in responding (R) patients (achieving at least PR at D28) compared to non-responding (NR) (44% vs 20% at M6 and 44% vs 13% at M12, logrank p=0.047). In EAP, OS was 48% at M6 and 37% at M12, and significantly higher in R patients compared to NR (71% vs 17% at M6 and 62% vs 6% at M12, logrank p In HERACLES, treatment with MaaT013 was characterized by excellent tolerance: 252 Treatment-Emergent Adverse Events (TEAE) were reported for the 24 patients, the majority being infections (79%) and GI disorders (62%), as expected in GvHD patients. Of these 252 TEAE, only 2% (5 serious events in 2 patients) could not reasonably be excluded from being related to MaaT013 by the investigators. Shotgun sequencing in these 5 TEAE revealed that the causative infectious agents could not be detected in the administered MaaT013. In EAP, the safety profile of MaaT013 was considered satisfactory for all patients. 16S microbiome analyses were performed in the HERACLES population and showed that MaaT013 produced an early increase in α-diversity at genus level with a significant increase in Richness index at all evaluated timepoints (p Conclusion We herein report the treatment of 76 SR-GI-aGvHD patients using a full ecosystem, pooled-donor, high-richness biotherapeutic. The D28 GI-ORR was 38% and 60% in HERACLES and EAP respectively and this clinical benefit positively and significantly impacted OS (44% and 62% M12 in HERACLES and EAP R patients respectively). MaaT013 was shown to be safe and effective in these heavily immunocompromised patients, warranting further exploration of this approach. Figure 1 Figure 1. Disclosures Malard: JAZZ pharmaceuticals: Honoraria; Sanofi: Honoraria; Astellas: Honoraria; Biocodex: Honoraria; Therakos/Mallinckrodt: Honoraria; Janssen: Honoraria. Loschi: CELGENE/BMS: Honoraria; AbbVie: Ended employment in the past 24 months, Honoraria; Gilead: Ended employment in the past 24 months, Honoraria; Novartis: Ended employment in the past 24 months, Honoraria; Servier: Ended employment in the past 24 months, Honoraria; MSD: Honoraria. Cluzeau: Agios: Honoraria; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses, Speakers Bureau; Roche: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria, Speakers Bureau; Jazz Pharma: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria, Speakers Bureau; Amgen: Speakers Bureau; Pfizer: Other: travel, accommodations, expenses; Astellas: Speakers Bureau; Takeda: Other: travel, accommodations, expenses. Huynh: Jazz Pharmaceuticals: Honoraria. Holler: MaaT Pharma: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Vehreschild: SocraTec R&D GmbH: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Ferring: Consultancy, Speakers Bureau; Farmak International Holding GmbH: Consultancy, Honoraria, Speakers Bureau; Bio-Mérieux: Consultancy, Speakers Bureau; Basilea: Consultancy, Speakers Bureau; Arderypharm: Consultancy, Speakers Bureau; Alb Fils Kliniken GmbH: Consultancy, Speakers Bureau; Takeda Pharmaceutical: Research Funding; Seres Therapeutics: Research Funding; Roche: Consultancy, Research Funding, Speakers Bureau; Organobalance: Consultancy, Research Funding, Speakers Bureau; Merck/MSD: Consultancy, Research Funding, Speakers Bureau; MaaT Pharma: Consultancy, Research Funding; Immunic AG: Consultancy, Research Funding, Speakers Bureau; Glycom: Research Funding; Gilead Sciences: Consultancy, Research Funding, Speakers Bureau; Evonik: Research Funding; Da Volterra: Consultancy, Research Funding, Speakers Bureau; Biontech: Research Funding; Astellas Pharma: Consultancy, Research Funding, Speakers Bureau; 3M: Research Funding. Gasc: MaaT Pharma: Current Employment. Plantamura: MaaT Pharma: Current Employment. Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria.

Background Haploidentical allogeneic hematopoietic cell transplantation (haplo-HCT) with post-transplant cyclophosphamide (PTCy) has greatly expanded potential donor options for patients (pts) without a fully HLA-matched donor. However, an HLA-mismatched unrelated donor (UD) or cord blood transplantation (CBT) are valid options for pts who do not have an haploidentical-related or a fully HLA-matched donor. The incorporation of PTCy with mismatched UD allo-HCT is associated with reduced risk of non-relapse mortality (NRM) and graft-versus-host disease (GvHD) (Jorge et al., BBMT, 2018). No previous study has compared outcomes of these two graft sources in contemporary era. In this study, we compared the outcomes of CBT versus (vs) single antigen-mismatched (HLA 9/10) UD allo-HCT with post-transplant cyclophosphamide (PTCy) in pts with acute myeloid leukemia (AML). Methods Pts with AML who underwent a first CBT without PTCy (N=902) or allo-HCT from a 9/10 UD with PTCy (N=280) between 2010 to 2019 were selected from The European Society of Blood and Marrow Transplantation (EBMT) registry. We excluded pts who had ex vivo T cell depletion. The median pt age was comparable between CBT and UD cohort [51 years (y) vs. 52 y, p=0.09]. The recipients of CBT had a longer median follow up (47 vs. 19 months, p Results In the univariate analysis, day +180 incidence of grade II-IV acute GvHD was 36% vs. 32% (p=0.07) and grade III-IV acute GvHD was 15% vs. 11% (p=0.16) for CBT and UD cohorts, respectively. The 2-y incidence of total chronic GvHD was 26% vs. 32% (p=0.20) and extensive chronic GvHD was 12% vs. 12% (p=0.83), respectively. CBT was associated with higher incidence of graft failure (11% vs. 4%, p In the MV analysis (Table 1), CBT was associated with higher risk of grade II-IV acute GvHD [hazard ratio (HR)=1.32, 95% confidence interval (CI):1-1.74,p Conclusions In this large registry-based observational study, CBT was associated with inferior LFS, OS and GRFS due to higher NRM and RI compared to 9/10 UD allo-HCT with PTCy. In the absence of a fully matched or haplo donor, 9/10 UD allo-HCT with PTCy may be preferred over CBT in pts with AML. A prospective study is needed to validate our findings. Disclosures Dholaria: Poseida: Research Funding; Angiocrine: Research Funding; Takeda: Research Funding; J&J: Research Funding; bms: Research Funding. Labopin:Jazz Pharmaceuticals: Honoraria. Blaise:Jazz Pharmaceuticals: Honoraria. Chevallier:Incyte Corporation: Honoraria. Mohty:BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; Stemline: Consultancy, Honoraria, Research Funding, Speakers Bureau; GSK: Consultancy, Honoraria, Research Funding, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau.

Background Assessment of measurable residual disease (MRD) is rapidly transforming the therapeutic and prognostic landscape of a wide range of hematological malignancies. Its prognostic value in acute lymphoblastic leukemia (ALL) has been established and MRD measured at the end of induction is increasingly used to guide further therapy. Although MRD detectable immediately before allogeneic hematopoietic cell transplantation (HCT) is known to be associated with poor outcomes, it is unclear if or to what extent this differs with different types of conditioning. Methods In this retrospective registry study, we explored whether measurable residual disease (MRD) before allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia is associated with different outcomes in recipients of myeloablative total body irradiation (TBI)-based versus chemotherapy-based conditioning. We analyzed outcomes of 2780 patients (median age 38 years, range 18–72) who underwent first HCT in complete remission between 2000 and 2017 using sibling or unrelated donors. Results In 1816 of patients, no disease was detectable, and in 964 patients, MRD was positive. Conditioning was TBI-based in 2122 (76%) transplants. In the whole cohort MRD positivity was a significant independent factor for lower overall survival (OS) and leukemia-free survival (LFS), and for higher relapse incidence (RI), with respective hazard ratios (HR, 95% confidence intervals) of 1.19 (1.02–1.39), 1.26 (1.1–1.44), and 1.51 (1.26–1.8). TBI was associated with a higher OS, LFS, and lower RI with HR of 0.75 (0.62–0.90), 0.70 (0.60–0.82), and 0.60 (0.49–0.74), respectively. No significant interaction was found between MRD status and conditioning. When investigating the impact of MRD separately in the TBI and chemotherapy-based conditioning cohorts by multivariate analysis, we found MRD positivity to be associated with lower OS and LFS and higher RI in the TBI group, and with higher RI in the chemotherapy group. TBI-based conditioning was associated with improved outcomes in both MRD-negative and MRD-positive patients. Conclusions In this large study, we confirmed that patients who are MRD-negative prior to HCT achieve superior outcomes. This is particularly apparent if TBI conditioning is used. All patients with ALL irrespective of MRD status benefit from TBI-based conditioning in the myeloablative setting.

Monosomy 7 or deletion 7q (-7/7q-) is the most frequent adverse cytogenetic features reported in acute myeloid leukemia (AML), and is a common indication for allogeneic stem cell transplantation (SCT). Nevertheless, -7/7q- occurs frequently with other high-risk cytogenetic abnormalities such as complex karyotype (CK), monosomal karyotype (MK), monosomy 5 or deletion 5q (-5/5q-), 17p abnormalities (abn(17p)) or inversion of chromosome 3 (inv(3)), the presence of which may influence the outcomes after SCT. A total of 1109 patients were allocated to this study. Two-year probability of leukemia-free survival (LFS) and overall survival (OS) were 30% and 36%, respectively. Two-year probability of non-relapse mortality (NRM) was 20%. We defined five different cytogenetic subgroups: the "-7/7q- +/- CK group- designated group1," the "MK group-designated group 2," the "-5/5q- group- designated group 3," the "abn(17p) group- designated group 4" and the "inv(3) group- designated group 5." The 2-year probability of LFS in first remission was 48% for group 1, 36.4% for group 2, 28.4% for group 3, 19.1% for group 4 and 17.3% for group 5, respectively (P