Posttransplant cyclophosphamide versus anti-thymocyte globulin versus combination for graft-versus-host disease prevention in haploidentical transplantation for adult acute myeloid leukemia: A report from the European Society for Blood and Marrow Transplantation Acute Leukemia Working Party.

BACKGROUND: The optimal choice for graft-versus-host disease (GVHD) prophylaxis in haploidentical stem cell transplantation (haplo-SCT) remains debatable. Posttransplant cyclophosphamide (PTCy) and anti-thymocyte globulin (ATG) are two common strategies, but little is known about their combination. METHODS: Using the European Society for Blood and Marrow Transplantation (EBMT) registry, the authors identified 3649 adult patients with acute myeloid leukemia (AML) who underwent haplo-SCT in complete remission between 2007 and 2021 at 260 EBMT-participating centers who received either PTCy (n = 2999), ATG (n = 358), or combination prophylaxis (n = 292). Cord blood transplants, combined bone marrow and peripheral grafts, and transplants with ex vivo graft manipulation were excluded. Median follow-up was 31.8 months. RESULTS: On multivariate analysis, adjusting for patient age and performance status, disease status at transplant, cytogenetic risk, conditioning intensity, stem cell source, female-to-male graft, and donor and patient CMV status, we present the following. Compared to PTCy, ATG had a higher risk of nonrelapse mortality (hazard ratio [HR], 1.6; p = .003), worse leukemia-free survival (HR, 1.4; p = .002), overall survival (HR, 1.49; p = .0009), and GVHD-free and relapse-free survival (HR, 1.29; p = .012). The combination of PTCy and ATG, however, led to significantly reduced rates of grade 2-4 (HR, 0.51; p = .0003) and grade 3-4 (HR, 0.5; p = .018) acute GVHD and did not affect any transplant outcomes compared to PTCy without ATG. CONCLUSION: The authors conclude that ATG alone is a less effective prophylaxis strategy compared to PTCy, however, the combination of PTCy and ATG is superior to either monotherapy. They propose that this combination could be considered a potential new standard of care for GVHD prophylaxis in haplo-SCT for AML.

Comparison of autologous and allogeneic hematopoietic cell transplantation strategies in patients with primary plasma cell leukemia, with dynamic prediction modeling.

Primary plasma cell leukemia (pPCL) is a rare and challenging malignancy. There are limited data regarding optimum transplant approaches. We therefore undertook a retrospective analysis from 1998-2014 of 751 patients with pPCL undergoing one of four transplant strategies; single autologous transplant (single auto), single allogeneic transplant (allo-first) or a combined tandem approach with an allogeneic transplant following an autologous transplant (auto-allo) or a tandem autologous transplant (auto-auto). To avoid time bias, multiple analytic approaches were employed including Cox models with time-dependent covariates and dynamic prediction by landmarking. Initial comparisons were made between patients undergoing allo-first (n=70) versus auto-first (n=681), regardless of a subsequent second transplant. The allo-first group had a lower relapse rate (45.9%, 95% confidence interval [95% CI]: 33.2-58.6 vs. 68.4%, 64.4-72.4) but higher non-relapse mortality (27%, 95% CI: 15.9-38.1 vs. 7.3%, 5.2-9.4) at 36 months. Patients who underwent allo-first had a remarkably higher risk in the first 100 days for both overall survival and progression-free survival. Patients undergoing auto-allo (n=122) had no increased risk in the short term and a significant benefit in progression-free survival after 100 days compared to those undergoing single auto (hazard ratio [HR]=0.69, 95% CI: 0.52- 0.92; P=0.012). Auto-auto (n=117) was an effective option for patients achieving complete remission prior to their first transplant, whereas in patients who did not achieve complete remission prior to transplantation our modeling predicted that auto-allo was superior. This is the largest retrospective study reporting on transplantation in pPCL to date. We confirm a significant mortality risk within the first 100 days for allo-first and suggest that tandem transplant strategies are superior. Disease status at time of transplant influences outcome. This knowledge may help to guide clinical decisions on transplant strategy.

Clinical-Grade Expanded Regulatory T Cells Are Enriched with Highly Suppressive Cells Producing IL-10, Granzyme B, and IL-35.

In the setting of T cell-depleted, full-haplotype mismatched transplantation, adoptive immunotherapy with regulatory T cells (Tregs) and conventional T cells (Tcons) can prevent graft-versus-host disease (GVHD) and improve post-transplantation immunologic reconstitution and is associated with a powerful graft-versus-leukemia effect. To improve the purity and the quantity of the infused Tregs, good manufacturing practices (GMP)-compatible expansion protocols are needed. Here we expanded Tregs using an automated, clinical-grade protocol. Cells were extensively characterized in vitro, and their efficiency was tested in vivo in a mouse model. Tregs were selected by CliniMacs (CD4+CD25+, 94.5 ± 6.3%; FoxP3+, 63.7 ± 11.5%; CD127+, 20 ± 3%; suppressive activity, 60 ± 7%), and an aliquot of 100 × 106 was expanded for 14 days using the CliniMACS Prodigy System, obtaining 684 ± 279 × 106 cells (CD4+CD25+, 99.6 ± 0.2%; FoxP3+, 82 ± 8%; CD127+, 1.1 ± 0.8%; suppressive activity, 75 ± 12%). CD39 and CTLA4 expression levels increased from 22.4 ± 12% to 58.1 ± 13.3% (P < .05) and from 20.4 ± 6.7% to 85.4 ± 9.8% (P < .01), respectively. TIM3 levels increased from .4 ± .05% to 29 ± 16% (P < .05). Memory Tregs were the prevalent population, whereas naive Tregs almost disappeared at the end of the culture. mRNA analysis displayed significant increases in CD39, IL-10, granzyme B, and IL-35 levels at the end of culture period (P < .05). Conversely, IFNγ expression decreased significantly by day +14. Expanded Tregs were sorted according to TIM3, CD39, and CD62L expression levels (purity >95%). When sorted populations were analyzed, TIM3+ cells showed significant increases in IL-10 and granzyme B (P < .01) .When expanded Tregs were infused in an NSG murine model, mice that received Tcons only died of GVHD, whereas mice that received both Tcons and Tregs survived without GVHD. GMP grade expanded cells that display phenotypic and functional Treg characteristics can be obtained using a fully automated system. Treg suppression is mediated by multiple overlapping mechanisms (eg, CTLA-4, CD39, IL-10, IL-35, TGF-ß, granzyme B). TIM3+ cells emerge as a potentially highly suppressive population. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Influence of Donor and Recipient Gender on Telomere Maintenance after Umbilical Cord Blood Cell Transplantation: A Study by the Gruppo Italiano Trapianto Di Midollo Osseo.

Physiologic loss of telomerase activity in adult life determines progressive telomere length (TL) shortening. Inflammation and oxidative damage are established causes of TL loss; moreover, males have shorter telomeres compared with females. Despite these notions, mechanisms regulating TL maintenance are poorly defined. Because umbilical cord blood (UCB) cells harbor very long telomeres, not yet exposed to environmental damages, UCB transplantation (UCBT) provides a unique experimental setting to study determinants of TL in humans. TL dynamics were analyzed on peripheral blood mononuclear cells (MNCs) from 36 patients (median age, 42 years) undergoing UCBT. TL was studied at a median of 20 months after UCBT. A significantly longer TL (mean, 8698 bp; range, 6521 to 11,960) was documented in UCBT recipients compared with age-matched healthy control subjects (mean, 7396 bp; range, 4375 to 11,108; P < .01). Among variables potentially influencing TL maintenance, including recipient features, graft type, transplant procedure, and engraftment kinetics, only donor-recipient gender combination was associated with TL, with the longest TL in women receiving male UCB (mean, 10,063 bp; range, 8381 to 11,960). To further investigate this trend, telomerase activation was assessed in vitro. Experiments showed that telomerase subunits were preferentially upregulated in male-derived bone marrow MNCs exposed ex vivo to estradiol as compared with female MNCs. This implies an increased sensitivity of male-derived MNCs to telomerase activation induced by estradiol. The results suggest that extrinsic and modifiable factors such as hormonal status and female milieu could be major determinants of TL in humans, providing the rationale for investigating hormonal-based approaches to counteract telomere erosion and aging-related diseases.

Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease after Autologous or Allogeneic Hematopoietic Stem Cell Transplantation in Children: a retrospective study of the Italian Hematology-Oncology Association-Hematopoietic Stem Cell Transplantation Group.

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a potentially life-threatening complication that may develop after hematopoietic stem cell transplantation (HSCT). The aims of this retrospective multicenter study were to evaluate the incidence of SOS/VOD in a large cohort of children transplanted in centers across Italy by applying the new European Society for Blood and Marrow Transplantation (EBMT) criteria and to analyze the risk factors underlying this complication. We retrospectively reviewed data of pediatric HSCTs performed in 13 AIEOP (Associazione Italiana di Ematologia e Oncologia Pediatrica)-affiliated centers between January 2000 and April 2016. The new pediatric EBMT criteria were retrospectively applied for diagnoses of SOS/VOD and severity grading. Among 5072 transplants considered at risk for SOS/VOD during the study period, 103 children (2%) developed SOS/VOD, and the grade was severe or very severe in all patients. The median time of SOS/VOD occurrence was 17 days after HSCT (range, 1 to 104). Sixty-nine patients (67%) were treated with defibrotide for a median time of 16 days (range, 4 to 104). In multivariable analysis age < 2 years, use of busulfan during the conditioning regimen, female gender, and hemophagocytic lymphohistiocytosis were risk factors statistically associated with the development of SOS/VOD. The overall mortality directly related to SOS/VOD was 15.5%. Overall survival at 1 year was worse in patients with SOS/VOD (P = .0033), and this difference disappeared 5 years after HSCT. Nonrelapse mortality was significantly higher 1 and 5 years after transplantation in patients who developed SOS/VOD (P < .001). Based on the application of new EBMT criteria, the overall incidence of SOS/VOD recorded in this large Italian pediatric retrospective study was 2%. Nonrelapse mortality was significantly higher in patients who developed SOS/VOD. Identifying the risk factors associated with SOS/VOD can lead to more effective early treatment strategies of this potentially fatal HSCT complication in childhood.

Outcome of Allogeneic Hematopoietic Stem Cell Transplantation in Adult Patients with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia in the Era of Tyrosine Kinase Inhibitors: A Registry-Based Study of the Italian Blood and Marrow Transplantation Society (GITMO).

We performed a nationwide registry-based analysis to describe the clinical outcome of adult patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) who underwent an allogeneic hematopoietic stem cell transplantation (HSCT) after a tyrosine kinase inhibitor (TKI)-based treatment A total of 441 patients were included in the study. The median age at HSCT was 44 years (range, 18 to 70 years). All 441 patients (100%) received TKI before HSCT (performed between 2005 and 2016). Of these 441 patients, 404 (92%) were in cytologic complete remission (CR), whereas the remaining 37 (8%) had active disease at the time of HSCT. Molecular minimal residual disease (MRD) was negative in 147 patients (36%) at the time of HSCT. The donor was unrelated in 46% of patients. The most prevalent source of stem cells was peripheral blood (70%). The conditioning regimen was myeloablative in 82% of cases (total body irradiation-based in 50%) and included antithymocyte globulin in 51% of patients. With a median follow-up after HSCT of 39.4 months (range, 1 to 145 months), the probability of overall survival (OS) at 1, 2, and 5 years was 69.6%, 61.1% and 50.3%, respectively, with a median OS of 62 months. Progression-free survival (PFS) at 1, 2, and 5 years was 60.2%, 52.1% and 43.7%, respectively. OS and PFS were significantly better in patients who were in CR and MRD-negative at the time of HSCT compared with patients who were in CR but MRD-positive (50% OS not reached versus 36 months; P = .015; 50% PFS not reached versus 26 months, P = .003). The subgroup of MRD-negative patients both at HSCT and at 3 months after HSCT had a better outcome (5-year OS, 70%). Conversely, the 37 patients who underwent a HSCT with active Ph+ ALL had a median OS of 7 months and a median PFS of 5 months. The 5-year cumulative incidence of relapse was significantly lower in MRD-negative patients (19.5% versus 35.4%; P = .001). Nonrelapse mortality (NRM) after 1, 2, and 5 years was 19.1% (95% confidence interval [CI], 15.5% to 22.9%), 20.7% (95% CI, 17% to 24.7%), and 24.1% (95% CI, 20% to 28.5%), respectively. NRM was significantly lower with a modified European Society for Blood and Marrow Transplantation (mEBMT) risk score of 0 to 2 compared with ≥3 (15% versus 25%; P = .016). The median OS for Ph+ ALL patients who underwent a TKI-based treatment followed by an allogeneic HSCT, in recent years at the GITMO centers, was 62 months. Evaluation of the mEBMT risk score can be useful to predict NRM. Our data confirm that HSCT is a potentially curative treatment for Ph+ ALL with an excellent outcome for the subgroup of MRD-negative patients both at HSCT and at 3 months after HSCT (5-year OS, 70%).

Impact of conditioning intensity on outcomes of haploidentical stem cell transplantation for patients with acute myeloid leukemia 45 years of age and over.

BACKGROUND: T cell-replete haploidentical stem cell transplantation (haplo-SCT) is a valid therapeutic option for adult patients with high-risk acute myeloid leukemia (AML) lacking an HLA-matched sibling or unrelated donor. METHOD: We retrospectively analyzed the outcomes of 912 AML patients ≥45 years of age who had undergone haplo-SCT with either myeloablative conditioning (MAC; n = 373) or reduced intensity conditioning (RIC; n = 539) regimens. RESULTS: The median follow-up was 31.1 and 25.7 months for MAC and RIC, respectively. The incidence of relapse and nonrelapse mortality (NRM) were 25.1% versus 28.7% and 31.0% versus 30.3% for MAC and RIC, respectively; 2-year leukemia-free survival (LFS) was 43.9% for MAC versus 41.0% for RIC. In multivariate analysis, the use of MAC versus RIC was not associated with a difference in the outcomes. Results were confirmed in the propensity score-weighted analysis. Disease status and performance status at transplantation were associated with outcomes. Notably, the use of posttransplantation cyclophosphamide was associated with reduced acute graft-versus-host disease (aGVHD) stage III-IV, and NRM and increased overall survival, LFS, and GVHD-free, relapse-free survival. The use of mobilized peripheral blood stem cells was associated with an increased risk of stage II-IV aGVHD. CONCLUSION: No differences were found between MAC and RIC regimens for haplo-SCT in adults with AML who were ≥45 years of age. The type of GVHD prophylaxis, disease status, and performance status were the major predictors of transplantation outcome. These results may serve as the background for randomized study comparing RIC versus MAC for haplo-SCT in adults with AML.

Second allogeneic stem cell transplantation in patients with acute lymphoblastic leukaemia: a study on behalf of the Acute Leukaemia Working Party of the European Society for Blood and Marrow Transplantation.

Although second allogeneic haematopoietic cell transplantation (allo-HCT2) is a therapeutic option for patients relapsing after first HCT (allo-HCT1), there is limited data on allo-HCT2 in patients with acute lymphoblastic leukaemia (ALL). We retrospectively studied 245 patients receiving allo-HCT2 as a salvage treatment for relapse following allo-HCT1 between the 2000 and 2017. The median age at allo-HCT2 was 34·6 years (range: 18-74). One hundred and one patients (41%) received sibling donor and 144 (59%) unrelated donor allo-HCT2. Acute graft-versus-host disease (GVHD) grade II-IV and III-IV occurred in 33% and 17% of the patients, respectively. The incidence of 2-year total and extensive chronic GVHD was 38% and 19%, respectively. The 2- and 5-year cumulative incidence of non-relapse mortality, relapse incidence, leukaemia-free survival, overall survival and GVHD-free, relapse-free survival (GRFS) were 24% and 26%, 56% and 62%, 20% and 12%, 30% and 14% and 12% & 7%, respectively. In multivariate analysis, factors associated with overall survival were age, time from allo-HCT1 to relapse, conditioning for allo-HCT1, Karnofsky score at allo-HCT2 and donor type for allo-HCT2. In conclusion, outcomes of allo-HCT2 in ALL patients were poor, with only 14% overall survival and 7% GRFS at 5 years with very high relapse incidence.

Minimal residual disease status predicts outcome of acute myeloid leukaemia patients undergoing T-cell replete haploidentical transplantation. An analysis from the Acute Leukaemia Working Party (ALWP) of the European Society for Blood and Marrow Transplantation (EBMT).

Assessment of minimal residual disease (MRD) is being routinely used to assess response in patients with acute myeloid leukaemia (AML). While it is well established that pre-transplant positive MRD studies predict for relapse in patients transplanted either from matched sibling donors or matched unrelated donors, it is currently unknown whether MRD has comparable prognostic value in haploidentical stem cell transplantation (haplo-SCT). To this end we performed a retrospective analysis using the Acute Leukaemia Working Party/European Society of Blood and Marrow Transplantation multicentre registry. All adult AML patients with known MRD status at transplant who underwent a first T-cell replete haplo-SCT while in remission between 2006 and 2016 were included. Two hundred and sixty-five MRD-negative and 128 MRD-positive patients were assessed. In multivariate analysis, MRD-negative patients experienced lower relapse incidence and better leukaemia-free survival (LFS) compared to MRD-positive patients. Subset analysis for MRD-positive patients revealed that patients with donors positive for cytomegalovirus experienced decreased relapse rates as well as increased survival. A 6-month landmark analysis suggests that the clinical benefit of pre-transplant MRD negativity in terms of relapse, overall survival and LFS is realized at this time point. Pre-transplant MRD status is potentially a pivotal prognosticator of outcome in AML patients undergoing T-cell replete haplo-SCT.

Outcomes of hematopoietic stem cell transplantation from unmanipulated haploidentical versus matched sibling donor in patients with acute myeloid leukemia in first complete remission with intermediate or high-risk cytogenetics: a study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Allogeneic hematopoietic stem cell transplantation is the optimal care for patients with high-risk or intermediate - acute myeloid leukemia. In patients lacking matched sibling donor, haploidentical donors are an option. We compared outcomes of unmanipulated (Haplo) to matched sibling donor transplant in acute myeloid leukemia patients in first complete remission. Included were intermediate and high-risk acute myeloid leukemia in first complete remission undergoing Haplo and matched sibling donor transplant from 2007-2015, and reported to the ALWP of the EBMT. A propensity score technique was used to confirm results of main analysis: 2 matched sibling donors were matched with 1 Haplo. We identified 2654 pts (Haplo =185; matched sibling donor =2469), 2010 with intermediate acute myeloid leukemia (Haplo=122; matched sibling donor =1888) and 644 with high-risk acute myeloid leukemia (Haplo =63; matched sibling donor =581). Median follow up was 30 (range 1-116) months. In multivariate analysis, in intermediate - acute myeloid leukemia patients, Haplo resulted in lower leukemia-free survival (Hazard Ratio 1.74; P<0.01), overall-survival (HR 1.80; P<0.01) and GvHD-free-relapse-free survival (Hazard Ratio 1.32; P<0.05) and higher graft-versus-host disease (GvHD) non-relapse mortality (Hazard Ratio 3.03; P<0.01) as compared to matched sibling donor. In high-risk acute myeloid leukemia, no differences were found in leukemia-free survival, overall-survival, and GvHD-free- relapse-free survival according to donor type. Higher grade II-IV acute GvHD was observed for Haplo in both high-risk (Hazard Ratio 2.20; P<0.01) and intermediate risk (Hazard Ratio 1.84; P<0.01). A trend for a lower Relapse-Incidence was observed in Haplo among high-risk acute myeloid leukemia (Hazard Ratio 0.56; P=0.06). The propensity score analysis confirmed results. Our results underline that matched sibling donor is the first choice for acute myeloid leukemia patients in first complete remission. On the other hand, results of Haplo transplants are similar to matched sibling donor transplants in acute myeloid leukemia patients with high risk cytogenetics.

Haploidentical transplantation outcomes for secondary acute myeloid leukemia: Acute Leukemia Working Party (ALWP) of the European Society for Blood and Marrow Transplantation (EBMT) study.

Secondary acute myeloid leukemia (sAML) traditionally has inferior outcomes compared to de novo AML. Allogeneic hematopoietic cell transplantation (HCT) is the sole potentially curative therapy. This study analyzes the outcomes for unmanipulated haploidentical HCT (haploHCT) for sAML using the Acute Leukemia Working Party (ALWP) registry of the European Society for Blood and Marrow Transplantation (EBMT). We identified 154 patients with sAML who underwent haploHCT from 2006 to 2016. Median age at HCT was 60 years with time from diagnosis to HCT 5 months. At transplantation, 69 patients were in first CR and 85 had active disease. Fifty-seven (38.0%) patients underwent myeloablative conditioning and 97 (62.0%) reduced intensity conditioning (RIC) conditioning. Multivariate analysis showed that there was no difference in RI, nonrelapse mortality (NRM), leukemia free survival (LFS), overall survival (OS), or GVHD-free/relapse free survival (GRFS) for conditioning intensity, age, performance status, or graft source. Active disease was associated with higher RI and inferior LFS, OS, and GRFS compared with patients in CR at time of transplant. T-cell depletion with anti-thymoglobulin resulted in higher NRM and inferior LFS, OS, and GRFS compared to post-transplant cyclophosphamide (PTCy) (HR 2.25, 2.01, 2.16, and 1.73, respectively with P values <.05). Our data shows that haploHCT is a feasible alternative for sAML when matched transplantation is unavailable.

Thiotepa, busulfan and fludarabine compared to busulfan and cyclophosphamide as conditioning regimen for allogeneic stem cell transplant from matched siblings and unrelated donors for acute myeloid leukemia.

Busulfan plus cyclophosphamide (BuCy) is the traditional conditioning regimen for allogeneic stem cell transplant (allo-SCT) for young, fit patients with acute myeloid leukemia (AML). The thiotepa-busulfan-fludarabine (TBF) protocol has recently demonstrated promising outcome in cord blood and haploidentical SCT; however, there is limited evidence about this regimen in transplant from matched siblings (MSD) and unrelated donors (UD). We retrospectively compared outcomes of 2523 patients aged 18-50 with AML in remission, undergoing transplant from MSD or UD prepared with either TBF or BuCy conditioning. A 1:3 pair-matched analysis was performed: 146 patients receiving TBF were compared with 438 patients receiving BuCy. Relapse risk was significantly lower in the TBF when compared with BuCy group (HR 0.6, P = .02), while NRM did not differ. No significant difference was observed in LFS and OS between the two regimens. TBF was associated with a trend towards higher risk of grades III-IV aGVHD (HR 1.8, P = .06) and inferior cGVHD (HR 0.7, P = .04) when compared with BuCy. In patients undergoing transplant in first remission, the advantage for TBF in terms of relapse was more evident (HR 0.4, P = .02), leading to a trend for better LFS in favor of TBF (HR 0.7, P = .10), while OS did not differ between the two cohorts. In conclusion, TBF represents a valid myeloablative conditioning regimen providing significantly lower relapse and similar survival when compared with BuCy. Patients in first remission appear to gain the most from this protocol, as in this subgroup a tendency for better LFS was observed when compared with BuCy.

T-cell replete haploidentical stem cell transplantation attenuates the prognostic impact of FLT3-ITD in acute myeloid leukemia: A report from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Acute myeloid leukemia (AML) patients harboring the FLT3-ITD mutation are considered a high risk patient subset preferentially allocated for allogeneic stem cell transplantation in first remission. Whether FLT3-ITD retains a prognostic role in haploidentical stem cell transplantation (haplo-SCT) is unknown. To analyze the prognostic impact of FLT3-ITD in haplo-SCT, we performed a retrospective analysis of the multicenter registry of the acute leukemia working party of the European Society for Blood and Marrow Transplantation. We included all adult AML patients with known FLT3 status who underwent a first T-cell replete related haplo-HCT in first complete remission from 2005 to 2016. We evaluated 293 patients of whom 202 were FLT3wt and 91 were FLT3-ITD mutated. FLT3-ITD patients were more likely to be NPM1 mutated as well as be in the intermediate risk cytogenetic risk category. In multivariate analysis, patients with FLT3-ITD had comparable rates of relapse incidence [Hazard ratio (HR) = 1.34, confidence interval (CI) 95%, 0.67-2.7; P = .9] and leukemia-free survival (HR = 0.99, CI 95%, 0.62-1.57; P = .9) to those of FLT3wt patients. Overall survival, the incidence of nonrelapse mortality, and graft versus host disease-free/relapse-free survival were not significantly impacted by FLT3-ITD status. Furthermore, relapse and overall survival were comparable between FLT3-ITD patients transplanted from various donor pools, namely matched siblings, unrelated donors, haplo-SCT). Finally, subset analysis of patients with intermediate risk cytogenetics confirmed the absence of a prognostic impact of FLT3-ITD also for this patient segment. In AML patients undergoing T-cell replete haplo-SCT, the FLT3-ITD mutation possibly does not retain its prognostic significance.

Incidence, Risk Factors and Outcome of Pre-engraftment Gram-Negative Bacteremia After Allogeneic and Autologous Hematopoietic Stem Cell Transplantation: An Italian Prospective Multicenter Survey.

BACKGROUND: Gram-negative bacteremia (GNB) is a major cause of illness and death after hematopoietic stem cell transplantation (HSCT), and updated epidemiological investigation is advisable. METHODS: We prospectively evaluated the epidemiology of pre-engraftment GNB in 1118 allogeneic HSCTs (allo-HSCTs) and 1625 autologous HSCTs (auto-HSCTs) among 54 transplant centers during 2014 (SIGNB-GITMO-AMCLI study). Using logistic regression methods. we identified risk factors for GNB and evaluated the impact of GNB on the 4-month overall-survival after transplant. RESULTS: The cumulative incidence of pre-engraftment GNB was 17.3% in allo-HSCT and 9% in auto-HSCT. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the most common isolates. By multivariate analysis, variables associated with GNB were a diagnosis of acute leukemia, a transplant from a HLA-mismatched donor and from cord blood, older age, and duration of severe neutropenia in allo-HSCT, and a diagnosis of lymphoma, older age, and no antibacterial prophylaxis in auto-HSCT. A pretransplant infection by a resistant pathogen was significantly associated with an increased risk of posttransplant infection by the same microorganism in allo-HSCT. Colonization by resistant gram-negative bacteria was significantly associated with an increased rate of infection by the same pathogen in both transplant procedures. GNB was independently associated with increased mortality at 4 months both in allo-HSCT (hazard ratio, 2.13; 95% confidence interval, 1.45-3.13; P <.001) and auto-HSCT (2.43; 1.22-4.84; P = .01). CONCLUSIONS: Pre-engraftment GNB is an independent factor associated with increased mortality rate at 4 months after auto-HSCT and allo-HSCT. Previous infectious history and colonization monitoring represent major indicators of GNB. CLINICAL TRIALS REGISTRATION: NCT02088840.

Steroid treatment of acute graft-versus-host disease grade I: a randomized trial.

Patients with acute graft-versus-host disease (GvHD) grade I were randomized to an observation arm (n=85) or to a treatment arm (n=86) consisting of 6-methylprednisolone 1 mg/kg/day, after stratification for age and donor type. The primary end point was development of grade II-IV GvHD. The cumulative incidence of grade II-IV GvHD was 50% in the observation arm and 33% in the treatment arm (P=0.005). However, grade III-IV GvHD was comparable (13% vs 10%, respectively; P=0.6), and this was true for sibling and alternative donor transplants. Moderate/severe chronic GvHD was also comparable (17% vs 9%). In multivariate analysis, an early interval between transplant and randomization (

Post-transplant cyclophosphamide versus anti-thymocyte globulin as graft- versus-host disease prophylaxis in haploidentical transplant.

Severe graft-versus-host disease is a major barrier for non-T-cell-depleted haploidentical stem cell transplantation. There is no consensus on the optimal graft-versus-host disease prophylaxis. This study compared the two most commonly used graft-versus-host disease prophylaxis regimens (post-transplant cyclophosphamide-based vs. the anti-thymocyte globulin-based) in adults with acute myeloid leukemia reported to the European Society for Blood and Bone Marrow Transplantation. A total of 308 patients were analyzed; 193 received post-transplant cyclophosphamide-based regimen and 115 anti-thymocyte globulin-based regimen as anti-graft-versus-host disease prophylaxis. The post-transplant cyclophosphamide-based regimen was more likely to be associated to bone marrow as graft source (60% vs. 40%; P=0.01). Patients in the post-transplant cyclophosphamide-based regimen group had significantly less grade 3-4 acute graft-versus-host disease than those in the anti-thymocyte globulin-based group (5% vs. 12%, respectively; P=0.01), comparable to chronic graft-versus-host disease. Multivariate analysis showed that non-relapse mortality was lower in the post-transplant cyclophosphamide-based regimen group [22% vs. 30%, Hazard ratio (HR) 1.77(95%CI: 1.09-2.86); P=0.02] with no difference in relapse incidence. Patients receiving post-transplant cyclophosphamide-based regimen had better graft-versus-host disease-free, relapse-free survival [HR 1.45 (95%CI: 1.04-2.02); P=0.03] and leukemia-free survival [HR 1.48 (95%CI: 1.03-2.12); P=0.03] than those in the anti-thymocyte globulin-based group. In the multivariate analysis, there was also a trend for a higher overall survival [HR 1.43 (95%CI: 0.98-2.09); P=0.06] for post-transplant cyclophosphamide-based regimen versus the anti-thymocyte globulin-based group. Notably, center experience was also associated with non-relapse mortality and graft-versus-host disease-free, relapse-free survival. Haplo-SCT using a post-transplant cyclophosphamide-based regimen can achieve better leukemia-free survival and graft-versus-host disease-free, relapse-free survival, lower incidence of graft-versus-host disease and non-relapse mortality as compared to anti-thymocyte globulin-based graft-versus-host disease prophylaxis in patients with acute myeloid leukemia.

Hematopoietic, Mesenchymal, and Immune Cells Are More Enhanced in Bone Marrow than in Peripheral Blood from Granulocyte Colony-Stimulating Factor Primed Healthy Donors.

The use of granulocyte colony-stimulating factor (G-CSF) primed bone marrow (G-BM) has been recently considered as an alternative to mobilized hematopoietic stem cells from peripheral blood (G-PB), especially in the haploidentical transplant setting. The purpose of this study was to compare the effect of in vivo G-CSF priming on BM and PB hematopoietic, mesenchymal (MSC), and immune cells. Forty healthy donors undergoing BM harvest for haploidentical transplant were given subcutaneous recombinant human G-CSF for 7 days. BM and PB samples were harvested on days -7 and 0. The hematopoietic stem/progenitor cells increased significantly after G-CSF priming in both BM and PB with a selective rise of BM CD34(+)CD38(-) cell subset. A striking enhancement of the mesenchymal progenitors was detected in G-BM. CD3(+), CD4(+), CD8(+), and CD19(+) cell fractions; the naive CD4(+) and CD8(+) subpopulations; and natural killer and regulatory T cells increased in G-BM, whereas only slight changes were detected in PB. Myeloid dendritic cells (DC1) were significantly up-regulated in both G-BM and G-PB, whereas DC2 increased only in G-BM. In conclusion, our results show substantial differences in the biologic effects exerted by G-CSF at BM and PB levels on hematopoietic cells and immune cell fractions. Furthermore, the impressive rise of MSC progenitors in G-BM might also be relevant to provide MSCs for several clinical use.

Improved outcome of patients with relapsed/refractory Hodgkin lymphoma with a new fotemustine-based high-dose chemotherapy regimen.

High-dose chemotherapy (HDT) with autologous stem cell transplantation is the standard of care for relapsed/refractory (RR) Hodgkin lymphoma (HL). Given that HDT may cure a sizeable proportion of patients refractory to first salvage, development of newer conditioning regimens remains a priority. We present the results of a novel HDT regimen in which carmustine was substituted by a third-generation chloroethylnitrosourea, fotemustine, with improved pharmacokinetics and safety (FEAM; fotemustine, etoposide, cytarabine, melphalan) in 122 patients with RR-HL accrued into a prospective registry-based study. Application of FEAM resulted in a 2-year progression-free survival (PFS) of 73·8% [95% confidence interval (CI), 0·64-0·81] with median PFS, overall survival and time to progression yet to be reached. The 2-year risk of progression adjusted for the competitive risk of death was 19·4% (95% CI, 0·12-0·27) for the entire patient population. Most previously established independent risk factors, except for fluorodeoxyglucose ((18) (F) FDG)-uptake, were unable to predict for disease progression and survival after FEAM. Although 32% of patients had (18) (F) FDG-positrin emission tomography-positive lesions before HDT, the 2-year risk of progression adjusted for competitive risk of death was 19·4% (95% CI; 0·12-0·27). No unusual acute toxicities or early/late pulmonary adverse events were registered. FEAM emerges as an ideal HDT regimen for RR-HL patients typically pre-exposed to lung-damaging treatments.

Busulfan plus cyclophosphamide versus busulfan plus fludarabine as a preparative regimen for allogeneic haemopoietic stem-cell transplantation in patients with acute myeloid leukaemia: an open-label, multicentre, randomised, phase 3 trial.

BACKGROUND: The standard busulfan-cyclophosphamide myeloablative conditioning regimen is associated with substantial non-relapse mortality in patients older than 40 years with acute myeloid leukaemia who are undergoing allogeneic stem-cell transplantation. Because the combination of busulfan plus fludarabine has been proposed to reduce non-relapse mortality, we aimed to compare this treatment with busulfan plus cyclophosphamide as a preparative regimen in these patients. METHODS: We did an open-label, multicentre, randomised, phase 3 trial for patients with acute myeloid leukaemia at 25 hospital transplant centres in Italy and one in Israel. Eligible patients were aged 40-65 years, had an Eastern Cooperative Oncology Group performance status less than 3, and were in complete remission. Patients were randomly assigned 1:1 to receive intravenous busulfan plus cyclophosphamide or busulfan plus fludarabine. Treatment allocations were not masked to investigators or patients. Randomisation was done centrally via a dedicated web-based system using remote data entry, with patients stratified by donor type and complete remission status. Patients allocated to busulfan plus cyclophosphamide received intravenous busulfan 0·8 mg/kg four times per day during 2 h infusions for four consecutive days (16 doses from days -9 through -6; total dose 12·8 mg/kg) and cyclophosphamide at 60 mg/kg per day for two consecutive days (on days -4 and -3; total dose 120 mg/kg). Patients allocated to busulfan plus fludarabine received the same dose of intravenous busulfan (from days -6 through -3) and fludarabine at 40 mg/m(2) per day for four consecutive days (from days -6 through -3; total dose 160 mg/m(2)). The primary endpoint was 1-year non-relapse mortality, which was assessed on an intention-to-treat basis; safety outcomes were assessed in the per-protocol population. This trial has been completed and is registered with ClinicalTrials.gov, number NCT01191957. FINDINGS: Between Jan 3, 2008, and Dec 20, 2012, we enrolled and randomly assigned 252 patients to receive busulfan plus cyclophosphamide (n=125) or busulfan plus fludarabine (n=127). Median follow-up was 27·5 months (IQR 9·8-44·3). 1-year non-relapse mortality was 17·2% (95% CI 11·6-25·4) in the busulfan plus cyclophosphamide group and 7·9% (4·3-14·3) in the busulfan plus fludarabine group (Gray's test p=0·026). The most frequently reported grade 3 or higher adverse events were gastrointestinal events (28 [23%] of 121 patients in the busulfan plus cyclophosphamide group and 26 [21%] of 124 patients in the busulfan plus fludarabine group) and infections (21 [17%] patients in the busulfan plus cyclophosphamide group and 13 [10%] patients in the busulfan plus fludarabine group had at least one such event). INTERPRETATION: In older patients with acute myeloid leukaemia, the myeloablative busulfan plus fludarabine conditioning regimen is associated with lower transplant-related mortality than busulfan plus cyclophosphamide, but retains potent antileukaemic activity. Accordingly, this regimen should be regarded as standard of care during the planning of allogeneic transplants for such patients. FUNDING: Agenzia Italiana del Farmaco.