Q-HAM: a multicenter upfront randomized phase II trial of quizartinib and high-dose Ara-C plus mitoxantrone in relapsed/refractory AML with FLT3-ITD.

BACKGROUND: About 50% of older patients with acute myeloid leukemia (AML) fail to attain complete remission (CR) following cytarabine plus anthracycline-based induction therapy. Salvage chemotherapy regimens are based on high-dose cytarabine (HiDAC), which is frequently combined with mitoxantrone (HAM regimen). However, CR rates remain low, with less than one-third of the patients achieving a CR. FLT3-ITD has consistently been identified as an unfavorable molecular marker in both relapsed and refractory (r/r)-AML. One-quarter of patients who received midostaurin are refractory to induction therapy and relapse rate at 2 years exceeds 40%. The oral second-generation bis-aryl urea tyrosine kinase inhibitor quizartinib is a very selective FLT3 inhibitor, has a high capacity for sustained FLT3 inhibition, and has an acceptable toxicity profile. METHODS: In this multicenter, upfront randomized phase II trial, all patients receive quizartinib combined with HAM (cytarabine 3g/m2 bidaily day one to day three, mitoxantrone 10mg/m2 days two and three) during salvage therapy. Efficacy is assessed by comparison to historical controls based on the matched threshold crossing approach with achievement of CR, complete remission with incomplete hematologic recovery (CRi), or complete remission with partial recovery of peripheral blood counts (CRh) as primary endpoint. During consolidation therapy (chemotherapy and allogeneic hematopoietic cell transplantation), patients receive either prophylactic quizartinib therapy or measurable residual disease (MRD)-triggered preemptive continuation therapy with quizartinib according to up-front randomization. The matched threshold crossing approach is a novel study-design to enhance the classic single-arm trial design by including matched historical controls from previous clinical studies. It overcomes common disadvantages of single-armed and small randomized studies, since the expected outcome of the observed study population can be adjusted based on the matched controls with a comparable distribution of known prognostic and predictive factors. Furthermore, balanced treatment groups lead to stable statistical models. However, one of the limitations of our study is the inability to adjust for unobserved or unknown confounders. Addressing the primary endpoint, CR/CRi/CRh after salvage therapy, the maximal sample size of 80 patients is assessed generating a desirable power of the used adaptive design, assuming a logistic regression is performed at a one-sided significance level α=0.05, the aspired power is 0.8, and the number of matching partners per intervention patient is at least 1. After enrolling 20 patients, the trial sample size will be recalculated in an interim analysis based on a conditional power argument. CONCLUSION: Currently, there is no commonly accepted standard for salvage chemotherapy treatment. The objective of the salvage therapy is to reduce leukemic burden, achieve the best possible remission, and perform a hemopoietic stem-cell transplantation. Thus, in patients with FLT3-ITD mutation, the comparison of quizartinib with intensive salvage therapy versus chemotherapy alone appears as a logical consequence in terms of efficacy and safety. ETHICS AND DISSEMINATION: Ethical approval and approvals from the local and federal competent authorities were granted. Trial results will be reported via peer-reviewed journals and presented at conferences and scientific meetings. TRIAL REGISTRATION: ClinicalTrials.gov NCT03989713; EudraCT Number: 2018-002675-17.

Treatment of adult ALL patients with third-generation CD19-directed CAR T cells: results of a pivotal trial.

BACKGROUND: Third-generation chimeric antigen receptor (CAR)-engineered T cells (CARTs) might improve clinical outcome of patients with B cell malignancies. This is the first report on a third-generation CART dose-escalating, phase-1/2 investigator-initiated trial treating adult patients with refractory and/or relapsed (r/r) acute lymphoblastic leukemia (ALL). METHODS: Thirteen patients were treated with escalating doses of CD19-directed CARTs between 1 × 106 and 50 × 106 CARTs/m2. Leukapheresis, manufacturing and administration of CARTs were performed in-house. RESULTS: For all patients, CART manufacturing was feasible. None of the patients developed any grade of Immune effector cell-associated neurotoxicity syndrome (ICANS) or a higher-grade (≥ grade III) catokine release syndrome (CRS). CART expansion and long-term CART persistence were evident in the peripheral blood (PB) of evaluable patients. At end of study on day 90 after CARTs, ten patients were evaluable for response: Eight patients (80%) achieved a complete remission (CR), including five patients (50%) with minimal residual disease (MRD)-negative CR. Response and outcome were associated with the administered CART dose. At 1-year follow-up, median overall survival was not reached and progression-free survival (PFS) was 38%. Median PFS was reached on day 120. Lack of CD39-expression on memory-like T cells was more frequent in CART products of responders when compared to CART products of non-responders. After CART administration, higher CD8 + and γδ-T cell frequencies, a physiological pattern of immune cells and lower monocyte counts in the PB were associated with response. CONCLUSION: In conclusion, third-generation CARTs were associated with promising clinical efficacy and remarkably low procedure-specific toxicity, thereby opening new therapeutic perspectives for patients with r/r ALL. Trial registration This trial was registered at www. CLINICALTRIALS: gov as NCT03676504.

KIR2DS4 and Its Variant KIR1D in KIR-AA Genotype Donors Showed Differential Survival Impact in Patients with Lymphoid Disease after HLA-Matched Unrelated Hematopoietic Stem Cell Transplantation.

Previous studies have illustrated associations between the presence of activating killer cell immunoglobulin-like receptor (KIR) genes and lower susceptibility to hematologic malignancies in humans. In addition, favorable hematopoietic stem cell transplantation (HSCT) outcomes have been reported in patients who received transplants from donors with KIR genotypes dominant for activating KIR receptors. However, the association of activating KIR genes on an allelic level with disease and their impact on HSCT outcome has been little investigated to date. To this end, we genotyped a large transplantation cohort for KIR 2 Ig domains and short cytoplasmic tail 4 (KIR2DS4) polymorphisms and investigated their association with disease. We next investigated the impact of KIR-AA genotype donor KIR2DS4 polymorphisms (AA/KIR2DS4 versus AA/ KIR 1 Ig domain [KIR1D]) on clinical outcomes of HSCT in myeloid versus lymphoid patient subgroups. Among 2810 transplantation donor-recipient pairs, 68.8% (n = 1934) were 10/10 HLA-matched and 31.2% (n = 876) were 9/10 HLA-matched. The distribution of KIR1D was equal in patients and donors (P = .205). Multivariate analysis in 10/10 HLA-matched patients with lymphoid disease showed improved HSCT outcomes when they received grafts from AA/KIR1D donors (overall survival: hazard ratio [HR], .62, P = .002; disease free survival: HR, .70, P = .011; graft-versus-host disease-free and relapse-free survival: HR, .67, P = .002; nonrelapse mortality: HR, .55, P < .001). This effect was not seen in either 9/10 HLA-matched patients with lymphoid disease or patients with myeloid disease. Our study indicates that the presence of KIR1D alleles is not associated with disease in patients, and, interestingly, using grafts from AA/KIR1D donors translated into beneficial survival outcomes in 10/10 HLA-matched patients with lymphoid disease.

Intensive chemotherapy with or without gemtuzumab ozogamicin in patients with NPM1-mutated acute myeloid leukaemia (AMLSG 09-09): a randomised, open-label, multicentre, phase 3 trial.

BACKGROUND: Acute myeloid leukaemia with mutated NPM1 is associated with high CD33 expression and intermediate-risk cytogenetics. The aim of this study was to evaluate intensive chemotherapy with or without the anti-CD33 antibody-drug conjugate gemtuzumab ozogamicin in participants with newly diagnosed, NPM1-mutated acute myeloid leukaemia. METHODS: This open-label, phase 3 trial was conducted at 56 hospitals in Germany and Austria. Eligible participants were 18 years or older and had newly diagnosed NPM1-mutated acute myeloid leukaemia and an Eastern Cooperative Oncology Group performance status of 0-2. Participants were randomly assigned, using age as a stratification factor (18-60 years vs >60 years), 1:1 to the two treatment groups using allocation concealment; there was no masking of participants and investigators to treatment groups. Participants received two cycles of induction therapy (idarubicin, cytarabine, and etoposide) plus all-trans retinoic acid (ATRA) followed by three consolidation cycles of high-dose cytarabine (or an intermediate dose for those older than 60 years) and ATRA, without or with gemtuzumab ozogamicin (3 mg/m2 administered intravenously on day 1 of induction cycles 1 and 2, and consolidation cycle 1). The primary endpoints were short-term event-free survival and overall survival in the intention-to-treat population (overall survival was added as a co-primary endpoint after amendment four of the protocol on Oct 13, 2013). The secondary endpoints were event-free survival with long-term follow-up, rates of complete remission, complete remission with partial haematological recovery (CRh), and complete remission with incomplete haematological recovery (CRi), cumulative incidences of relapse and death, and number of days in hospital. This trial is registered with ClinicalTrials.gov (NCT00893399) and has been completed. FINDINGS: Between May 12, 2010, and Sept 1, 2017, 600 participants were enrolled, of which 588 (315 women and 273 men) were randomly assigned (296 to the standard group and 292 to the gemtuzumab ozogamicin group). No difference was found in short-term event-free survival (short-term event-free survival at 6-month follow-up, 53% [95% CI 47-59] in the standard group and 58% [53-64] in the gemtuzumab ozogamicin group; hazard ratio [HR] 0·83; 95% CI 0·65-1·04; p=0·10) and overall survival between treatment groups (2-year overall survival, 69% [63-74] in the standard group and 73% [68-78] in the gemtuzumab ozogamicin group; 0·90; 0·70-1·16; p=0·43). There was no difference in complete remission or CRi rates (n=267 [90%] in the standard group vs n=251 [86%] in the gemtuzumab ozogamicin group; odds ratio [OR] 0·67; 95% CI 0·40-1·11; p=0·15) and complete remission or CRh rates (n=214 [72%] vs n=195 [67%]; OR 0·77; 0·54-1·10; p=0·18), whereas the complete remission rate was lower with gemtuzumab ozogamicin (n=172 [58%] vs n=136 [47%]; OR 0·63; 0·45-0·80; p=0·0068). Cumulative incidence of relapse was significantly reduced by gemtuzumab ozogamicin (2-year cumulative incidence of relapse, 37% [95% CI 31-43] in the standard group and 25% [20-30] in the gemtuzumab ozogamicin group; cause-specific HR 0·65; 0·49-0·86; p=0·0028), and there was no difference in the cumulative incidence of death (2-year cumulative incidence of death 6% [4-10] in the standard group and 7% [5-11] in the gemtuzumab ozogamicin group; HR 1·03; 0·59-1·81; p=0·91). There were no differences in the number of days in hospital across all cycles between treatment groups. The most common treatment-related grade 3-4 adverse events were febrile neutropenia (n=135 [47%] in the gemtuzumab ozogamicin group vs n=122 [41%] in the standard group), thrombocytopenia (n=261 [90%] vs n=265 [90%]), pneumonia (n=71 [25%] vs n=64 [22%]), sepsis (n=85 [29%] vs n=73 [25%]). Treatment-related deaths were documented in 25 participants (4%; n=8 [3%] in the standard group and n=17 [6%] in the gemtuzumab ozogamicin group), mostly due to sepsis and infections. INTERPRETATION: The primary endpoints of the trial of event-free survival and overall survival were not met. However, an anti-leukaemic efficacy of gemtuzumab ozogamicin in participants with NPM1-mutated acute myeloid leukaemia is shown by a significantly lower cumulative incidence of relapse rate, suggesting that the addition of gemtuzumab ozogamicin might reduce the need for salvage therapy in these participants. The results from this study provide further evidence that gemtuzumab ozogamicin should be added in the standard of care treatment in adults with NPM1-mutated acute myeloid leukaemia. FUNDING: Pfizer and Amgen.

Higher risk for chronic graft-versus-host disease (GvHD) in HLA-G mismatched transplants following allogeneic hematopoietic stem cell transplantation: A retrospective study.

INTRODUCTION: Graft-versus-host disease (GvHD) is a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is highly influenced by the degree of HLA matching between recipient and donor. The HLA-class Ib molecule HLA-G has been shown to promote tolerogenicity through its interaction with inhibitory receptors found on several immunocompetent cells. We hypothesized that in an allo-HSCT setting, HLA-G mismatches may negatively impact the HLA-G-mediated tolerogenicity either due to inefficient interaction with the inhibitory receptors of the transplanted immune cells or due to direct allorecognition of mismatched HLA-G on host cells by the immune cells of the donor. METHODS: In order to explore this hypothesis, we investigated the impact of HLA-G mismatching in 2.083 10/10 matched high resolution HLA-typed allo-HSCT transplants. RESULTS: We found that the risk of chronic GvHD was significantly higher in HLA-G-mismatched transplant cases as compared with the HLA-G-matched control group (HR: 1.46, 95%CI = 1.11-1.91, p = 0.006). Sub-analysis of the mismatch vector revealed that this effect was only detectable in the GvH (HR: 1.89, 95%CI 1.39-2.57, p < 0.001) but not the HvG direction (HR: 1.01, 95%CI = 0.63-1.63, p = 0.967). In addition, the negative impact of HLA-G mismatching on chronic GvHD was only significant in younger patients (<30y HR: 3.02, 95%CI = 1.25-7.28, p = 0.014; >29y HR: 1.28, 95%CI = 0.94-1.72, p = 0.113). DISCUSSION: Our results indicate that HLA-G mismatches may contribute to the onset of chronic GvHD, especially in younger patients and should therefore be avoided when possible.

Donor genetic determinant of thymopoiesis rs2204985 impacts clinical outcome after single HLA mismatched hematopoietic stem cell transplantation.

A common genetic variant within the T cell receptor alpha (TCRA)-T cell receptor delta (TCRD) locus (rs2204985) has been recently found to associate with thymic function. Aim of this study was to investigate the potential impact of donor rs2204985 genotype on patient's outcome after unrelated hematopoietic stem cell transplantation (uHSCT). 2016 adult patients were retrospectively analyzed. rs2204985 genotyping was performed by next generation sequencing, p < 0.05 was considered significant and donor rs2204985 GG/AG genotypes were set as reference vs. the AA genotype. Multivariate analysis of the combined cohort regarding the impact of donor's rs2204985 genotype indicated different risk estimates in 10/10 and 9/10 HLA matched transplantations. A subanalysis on account of HLA incompatibility revealed that donor AA genotype in single HLA mismatched cases (n = 624) associated with significantly inferior overall- (HR: 1.48, p = 0.003) and disease-free survival (HR: 1.50, p = 0.001). This effect was driven by a combined higher risk of relapse incidence (HR: 1.40, p = 0.026) and non-relapse mortality (HR: 1.38, p = 0.042). This is the first study to explore the role of rs2204985 in a clinical uHSCT setting. Our data suggest that donor rs2204985 AA genotype in combination with single HLA mismatches may adversely impact post-HSCT outcome and should thus be avoided.

Midostaurin plus intensive chemotherapy for younger and older patients with AML and FLT3 internal tandem duplications.

We conducted a single-arm, phase 2 trial (German-Austrian Acute Myeloid Leukemia Study Group [AMLSG] 16-10) to evaluate midostaurin with intensive chemotherapy followed by allogeneic hematopoietic-cell transplantation (HCT) and a 1-year midosta urin maintenance therapy in adult patients with acute myeloid leukemia (AML) and fms-related tyrosine kinase 3 (FLT3) internal tandem duplication (ITD). Patients 18 to 70 years of age with newly diagnosed FLT3-ITD-positive AML were eligible. Primary and key secondary endpoints were event-free survival (EFS) and overall survival (OS). Results were compared with a historical cohort of 415 patients treated on 5 prior AMLSG trials; statistical analysis was performed using a double-robust adjustment with propensity score weighting and covariate adjustment. Results were also compared with patients (18-59 years) treated on the placebo arm of the Cancer and Leukemia Group B (CALGB) 10603/RATIFY trial. The trial accrued 440 patients (18-60 years, n = 312; 61-70 years, n = 128). In multivariate analysis, EFS was significantly in favor of patients treated within the AMLSG 16-10 trial compared with the AMLSG control (hazard ratio [HR], 0.55; P < .001); both in younger (HR, 0.59; P < .001) and older patients (HR, 0.42; P < .001). Multivariate analysis also showed a significant beneficial effect on OS compared with the AMLSG control (HR, 0.57; P < .001) as well as to the CALGB 10603/RATIFY trial (HR, 0.71; P = .005). The treatment effect of midostaurin remained significant in sensitivity analysis including allogeneic HCT as a time-dependent covariate. Addition of midostaurin to chemotherapy was safe in younger and older patients. In comparison with historical controls, the addition of midostaurin to intensive therapy led to a significant improvement in outcome in younger and older patients with AML and FLT3-ITD. This trial is registered at clinicaltrialsregistry.eu as Eudra-CT number 2011-003168-63 and at clinicaltrials.gov as NCT01477606.

HLA-DRB3/4/5 Matching Improves Outcome of Unrelated Hematopoietic Stem Cell Transplantation.

The HLA-DRB3/4/5 loci are closely linked to the HLA-DRB1 gene. Mismatches in these loci occur with a frequency of about 8%-12% in otherwise 10/10 HLA-matched transplant pairs. There is preliminary evidence that these disparities may associate with increased acute graft-versus-host disease (GvHD) rates. The aim of this study was to analyze a large cohort of German patients and their donors for HLA-DRB3/4/5 compatibility and to correlate the HLA-DRB3/4/5 matching status with the outcome of unrelated hematopoietic stem cell transplantation (uHSCT). To this end, 3,410 patients and their respective donors were HLA-DRB3/4/5 and HLA-DPB1 typed by amplicon-based next-generation sequencing (NGS). All patients included received their first allogeneic transplant for malignant hematologic diseases between 2000 and 2014. Mismatches in the antigen recognition domain (ARD) of HLA-DRB3/4/5 genes were correlated with clinical outcome. HLA-DRB3/4/5 incompatibility was seen in 12.5% (n = 296) and 17.8% (n = 185) of the 10/10 and 9/10 HLA-matched cases, respectively. HLA-DRB3/4/5 mismatches in the ARD associated with a worse overall survival (OS), as shown in univariate (5-year OS: 46.1% vs. 39.8%, log-rank p = 0.038) and multivariate analyses [hazard ratio (HR) 1.25, 95% CI 1.02-1.54, p = 0.034] in the otherwise 10/10 HLA-matched subgroup. The worse outcome was mainly driven by a significantly higher non-relapse mortality (HR 1.35, 95% CI 1.05-1.73, p = 0.017). In the 9/10 HLA-matched cases, the effect was not statistically significant. Our study results suggest that mismatches within the ARD of HLA-DRB3/4/5 genes significantly impact the outcome of otherwise fully matched uHSCT and support their consideration upon donor selection in the future.

Upfront stem cell transplantation for newly diagnosed multiple myeloma with del(17p) and t(4;14): a study from the CMWP-EBMT.

We analyzed newly diagnosed multiple myeloma patients with del(17p) and/or t(4;14) undergoing either upfront single autologous (auto), tandem autologous (auto-auto) or tandem autologous/reduced-intensity allogeneic (auto-allo) stem cell transplantation. 623 patients underwent either auto (n = 446), auto-auto (n = 105), or auto-allo (n = 72) between 2000 and 2015. 46% of patients had t(4;14), 45% had del(17p) while 9% were reported having both abnormalities. Five-year overall survival (OS) was 51% (95% confidence interval [CI], 45-58%) for single auto, 60% (95% CI, 49-72%) for auto-auto, and 67% (95% CI, 53-80%) for auto-allo (p = 0.187). Five-year progression-free survival (PFS) was 17% (95% CI, 12-22%), 33% (95% CI, 22-43%), and 34% (95% CI, 21-38%; p = 0.048). Five-year relapse rate was 82, 63, and 56%, while non-relapse mortality was 1, 4, and 10%. In multivariable analysis, in t(4;14) with single auto as reference, auto-auto (hazard ratio [HR], 0.44; p = 0.007) and auto-allo (HR, 0.45; p = 0.018) were associated with better PFS. In terms of t(4;14) and OS, auto-auto appeared to improve outcome compared with single auto (HR, 0.49; p = 0.096). In del(17p), outcome in PFS was similar between single auto and auto-auto, while auto-allo appeared to improve PFS (HR, 0.65; p = 0.097). No significant difference in OS was identified between the groups in patients with del(17p).

The Human Leukocyte Antigen-DPB1 Degree of Compatibility Is Determined by Its Expression Level and Mismatch Permissiveness: A German Multicenter Analysis.

T-cell epitope matching according to the TCE3 algorithm classifies HLA-DPB1 mismatches in permissive and non-permissive. This classification has been shown to be predictive for mortality and acute GvHD (aGvHD) events in large international cohorts. We retrospectively genotyped HLA-DPB1 in 3523 patients transplanted in Germany between 2000 and 2014 and in their unrelated donors using an Illumina amplicon-NGS based assay. Aim of the study was to evaluate DP-compatibility beyond the established TCE3 algorithm by assessing the combined effect of several DP-mismatch parameters on post-transplant outcome. We implemented an extended DP-mismatch assessment model where TCE3, DP allotype expression with respect to rs9277534, mismatch vector and number of mismatches were conjointly taken into consideration. In this model, non-permissive HLA-DPB1 mismatches showed significantly increased aGvHD risk if they were accompanied by two HLA-DPB1 mismatches in GvH direction (HR: 1.46) or one mismatched highly expressed patient allotype (HR: 1.53). As previously reported, non-permissive HLA-DPB1 mismatches associated with a significantly higher risk of aGvHD and non-relapse mortality (HR 1.36 and 1.21, respectively), which in turn translated into worse GvHD and relapse free survival (HR 1.13). Effects on GvL and GvHD appeared strongest in GvH-directed non-permissive mismatches. Our study results support the consideration of additional HLA-DPB1 mismatch parameters along with the established TCE3 matching algorithm for refinement of future donor selection. In particular, our findings suggest that DP non-permissiveness associated with two HLA-DPB1 mismatches or at least on highly expressed mismatched patient allotype should be avoided.

Measurable residual disease monitoring in acute myeloid leukemia with t(8;21)(q22;q22.1): results from the AML Study Group.

We performed serial measurable residual disease (MRD) monitoring in bone marrow (BM) and peripheral blood (PB) samples of 155 intensively treated patients with RUNX1-RUNX1T1+ AML, using a qRT-PC-based assay with a sensitivity of up to 10-6. We assessed both reduction of RUNX1-RUNX1T1 transcript levels (TLs) and achievement of MRD negativity (MRD-) for impact on prognosis. Achievement of MR2.5 (>2.5 log reduction) after treatment cycle 1 and achievement of MR3.0 after treatment cycle 2 were significantly associated with a reduced risk of relapse (P = .034 and P = .028, respectively). After completion of therapy, achievement of MRD- in both BM and PB was an independent, favorable prognostic factor in cumulative incidence of relapse (4-year cumulative incidence relapse: BM, 17% vs 36%, P = .021; PB, 23% vs 55%, P = .001) and overall survival (4-year overall survival rate BM, 93% vs 70%, P = .007; PB, 87% vs 47%, P < .0001). Finally, during follow-up, serial qRT-PCR analyses allowed prediction of relapse in 77% of patients exceeding a cutoff value of 150 RUNX1-RUNX1T1 TLs in BM, and in 84% of patients exceeding a value of 50 RUNX1-RUNX1T1 TLs in PB. The KIT mutation was a significant factor predicting a lower CR rate and inferior outcome, but its prognostic impact was outweighed by RUNX1-RUNX1T1 TLs during treatment. Virtually all relapses occurred within 1 year after the end of treatment, with a very short latency from molecular to morphologic relapse, necessitating MRD assessment at short intervals during this time period. Based on our data, we propose a refined practical guideline for MRD assessment in RUNX1-RUNX1T1+ AML.

Midostaurin added to chemotherapy and continued single-agent maintenance therapy in acute myeloid leukemia with FLT3-ITD.

Patients with acute myeloid leukemia (AML) and a FLT3 internal tandem duplication (ITD) have poor outcomes to current treatment. A phase 2 hypothesis-generating trial was conducted to determine whether the addition of the multitargeted kinase inhibitor midostaurin to intensive chemotherapy followed by allogeneic hematopoietic cell transplantation (alloHCT) and single-agent maintenance therapy of 12 months is feasible and favorably influences event-free survival (EFS) compared with historical controls. Patients 18 to 70 years of age with newly diagnosed AML and centrally confirmed FLT3-ITD were eligible: 284 patients were treated, including 198 younger (18-60 years) and 86 older (61-70 years) patients. Complete remission (CR) rate, including CR with incomplete hematological recovery (CRi) after induction therapy, was 76.4% (younger, 75.8%; older, 77.9%). The majority of patients in CR/CRi proceeded to alloHCT (72.4%). Maintenance therapy was started in 97 patients (34%): 75 after alloHCT and 22 after consolidation with high-dose cytarabine (HiDAC). Median time receiving maintenance therapy was 9 months after alloHCT and 10.5 months after HiDAC; premature termination was mainly a result of nonrelapse causes (gastrointestinal toxicity and infections). EFS and overall survival at 2 years were 39% (95% confidence interval [CI], 33%-47%) and 34% (95% CI, 24%-47%) and 53% (95% CI, 46%-61%) and 46% (95% CI, 35%-59%) in younger and older patients, respectively. EFS was evaluated in comparison with 415 historical controls treated within 5 prospective trials. Propensity score-weighted analysis revealed a significant improvement of EFS by midostaurin (hazard ratio [HR], 0.58; 95% CI, 0.48-0.70; P < .001) overall and in older patients (HR, 0.42; 95% CI, 0.29-0.61). The study was registered at www.clinicaltrials.gov as #NCT01477606.

Adding dasatinib to intensive treatment in core-binding factor acute myeloid leukemia-results of the AMLSG 11-08 trial.

In this phase Ib/IIa study (ClinicalTrials.gov Identifier: NCT00850382) of the German-Austrian AML Study Group (AMLSG) the multikinase inhibitor dasatinib was added to intensive induction and consolidation chemotherapy and administered as single agent for 1-year maintenance in first-line treatment of adult patients with core-binding factor (CBF) acute myeloid leukemia (AML). The primary combined end point in this study was safety and feasibility, and included the rates of early (ED) and hypoplastic (HD) deaths, pleural/pericardial effusion 3°/4° and liver toxicity 3°/4°, and the rate of refractory disease. Secondary end points were cumulative incidence of relapse (CIR) and death in complete remission (CID), and overall survival (OS). Eighty-nine pts [median age 49.5 years, range: 19-73 years; t(8;21), n = 37; inv (16), n = 52] were included. No unexpected excess in toxicity was observed. The rates of ED/HD and CR/CRi were 4.5% (4/89) and 94% (84/89), respectively. The 4-year estimated CIR, CID, and OS were 33.1% [95%-CI (confidence interval), 22.7-43.4%], 6.0% (95% CI, 0.9-11.2%), and 74.7% (95% CI, 66.1-84.5%), respectively. On the basis of the acceptable toxicity profile and favorable outcome in the AMLSG 11-08 trial, a confirmatory randomized phase III trial with dasatinib in adults with CBF-AML is ongoing (ClinicalTrials.gov Identifier: NCT02013648).

Prospective noninterventional study on peripheral blood stem cell mobilization in patients with relapsed lymphomas.

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) to rescue hematopoiesis is considered standard care for patients with a relapsed chemosensitive lymphoma, but diagnosis of lymphoma has been a risk factor for poor mobilization in several studies. The aim of this prospective noninterventional clinical audit was to review the mobilization strategies used by EBMT centers in relapsed lymphoma and to evaluate their efficacy. Between 2010 and 2014, 275 patients with relapsed lymphoma from 30 EBMT centers were prospectively registered. Almost all patients were mobilized with chemotherapy plus G-CSF (96%), but there was a large variation in chemotherapy schedules. Thirty (11%) of them were poor mobilizers (<2 × 106 CD 34+ cells/kg body weight) at the first mobilization. Poor mobilization was not associated with gender, age, bone marrow involvement at diagnosis, primary diagnosis, number of previous chemotherapy lines, previous radiotherapy or mobilization with G-CSF alone. The use of high dose cyclophosphamide alone was associated with mobilization failure (P = 0.0006), whereas the use of a platinum-containing regimen was associated with a good mobilization outcome (P = 0.013). Because failure rate is low, we can conclude from this study that PBSC mobilization failure in relapsed lymphomas is not an important problem in the EBMT centers.

Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation.

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n = 157) HLA alleles. Within each HLA match group, cases matched and mismatched for MICA and MICA-129 were analyzed for the end points overall survival (OS), disease-free survival (DFS), nonrelapse mortality (NRM), relapse-incidence (RI), and GVHD. Mismatches at the MICA locus as well as MICA-129 increased with the number of HLA mismatches (MICA mismatched 10/10, 9.2% [n = 127]; 9/10, 22.3% [n = 142]; 8/10, 38.2% [n = 60]; MICA-129 mismatched 10/10, 3.9% [n = 54]; 9/10, 10.2% [n = 65]; 8/10, 17.2% [n = 27]). Adverse OS was observed in the 10/10 match group if MICA-129 was mismatched (10/10, hazard ratio [HR], 1.77; confidence interval [CI], 1.22-2.57; P = .003). MICA-129 mismatches correlated with a significantly worse outcome for DFS in the 10/10 HLA match group (HR, 1.77; CI, 1.26-2.50; P = .001). Higher rates of aGVHD were seen in MICA-129 mismatched cases. Our results indicate that MICA-129 matching is relevant in uHSCT. Prospective typing of patients and donors in unrelated donor search may identify mismatches for MICA-129, and compatible donor selection may improve outcome for this small but high-risk subgroup.

ASXL1 mutations in younger adult patients with acute myeloid leukemia: a study by the German-Austrian Acute Myeloid Leukemia Study Group.

We studied 1696 patients (18 to 61 years) with acute myeloid leukemia for ASXL1 mutations and identified these mutations in 103 (6.1%) patients. ASXL1 mutations were associated with older age (P<0.0001), male sex (P=0.041), secondary acute myeloid leukemia (P<0.0001), and lower values for bone marrow (P<0.0001) and circulating (P<0.0001) blasts. ASXL1 mutations occurred in all cytogenetic risk-groups; normal karyotype (40%), other intermediate-risk cytogenetics (26%), high-risk (24%) and low-risk (10%) cytogenetics. ASXL1 mutations were associated with RUNX1 (P<0.0001) and IDH2(R140) mutations (P=0.007), whereas there was an inverse correlation with NPM1 (P<0.0001), FLT3-ITD (P=0.0002), and DNMT3A (P=0.02) mutations. Patients with ASXL1 mutations had a lower complete remission rate (56% versus 74%; P=0.0002), and both inferior event-free survival (at 5 years: 15.9% versus 29.0%; P=0.02) and overall survival (at 5 years: 30.3% versus 45.7%; P=0.0004) compared to patients with wildtype ASXL1. In multivariable analyses, ASXL1 and RUNX1 mutation as a single variable did not have a significant impact on prognosis. However, we observed a significant interaction (P=0.04) for these mutations, in that patients with the genotype ASXL1(mutated)/RUNX1(mutated) had a higher risk of death (hazard ratio 1.8) compared to patients without this genotype. ASXL1 mutation, particularly in the context of a coexisting RUNX1 mutation, constitutes a strong adverse prognostic factor in acute myeloid leukemia.

Treatment of acute myeloid leukemia or myelodysplastic syndrome relapse after allogeneic stem cell transplantation with azacitidine and donor lymphocyte infusions--a retrospective multicenter analysis from the German Cooperative Transplant Study Group.

To expand the current knowledge about azacitidine (Aza) and donor lymphocyte infusions (DLI) as salvage therapy for relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and to identify predictors for response and survival, we retrospectively analyzed data of 154 patients with acute myeloid leukemia (AML, n = 124), myelodysplastic (MDS, n = 28), or myeloproliferative syndrome (n = 2). All patients received a median number of 4 courses of Aza (range, 4 to 14) and DLI were administered to 105 patients (68%; median number of DLI, 2; range, 1 to 7). Complete and partial remission rates were 27% and 6%, respectively, resulting in an overall response rate of 33%. Multivariate analysis identified molecular-only relapse (hazard ratio [HR], 9.4; 95% confidence interval [CI], 2.0 to 43.5; P = .004) and diagnosis of MDS (HR, 4.1; 95% CI, 1.4 to 12.2; P = .011) as predictors for complete remission. Overall survival (OS) at 2 years was 29% ± 4%. Molecular-only relapse (HR, .14; 95% CI, .03 to .59; P = .007), diagnosis of MDS (HR, .33; 95% CI, .16 to .67; P = .002), and bone marrow blasts <13% (HR, .54; 95% CI, .32 to .91; P = .021) were associated with better OS. Accordingly, 2-year OS rate was higher in MDS patients (66% ± 10%, P = .001) and correlated with disease burden in patients with AML. In summary, Aza and DLI is an effective and well-tolerated treatment option for patients with relapse after allo-HSCT, in particular those with MDS or AML and low disease burden. The latter finding emphasizes the importance of stringent disease monitoring and early intervention.

Differential impact of allelic ratio and insertion site in FLT3-ITD-positive AML with respect to allogeneic transplantation.

The objective was to evaluate the prognostic and predictive impact of allelic ratio and insertion site (IS) of internal tandem duplications (ITDs), as well as concurrent gene mutations, with regard to postremission therapy in 323 patients with FLT3-ITD-positive acute myeloid leukemia (AML). Increasing FLT3-ITD allelic ratio (P = .004) and IS in the tyrosine kinase domain 1 (TKD1, P = .06) were associated with low complete remission (CR) rates. After postremission therapy including intensive chemotherapy (n = 121) or autologous hematopoietic stem cell transplantation (HSCT, n = 17), an allelic ratio ≥ 0.51 was associated with an unfavorable relapse-free (RFS, P = .0008) and overall survival (OS, P = .004); after allogeneic HSCT (n = 93), outcome was significantly improved in patients with a high allelic ratio (RFS, P = .02; OS, P = .03), whereas no benefit was seen in patients with a low allelic ratio (RFS, P = .38; OS, P = .64). Multivariable analyses revealed a high allelic ratio as a predictive factor for the beneficial effect of allogeneic HSCT; ITD IS in TKD1 remained an unfavorable factor, whereas no prognostic impact of concurrent gene mutations was observed. The clinical trials described herein were previously published or are registered as follows: AMLHD93 and AMLHD98A, previously published; AML SG 07-04, ClinicalTrials.gov identifier #NCT00151242.