ALBERT

Description: Introduction: Blinatumomab is a bispecific, CD19-directed CD3 T-cell engager (BiTE®) that activates endogenous cytotoxic T cells to kill target B cells and is FDA-approved for the treatment of relapsed or refractory (R/R) B-cell precursor acute lymphoblastic leukemia (B-ALL). Subgroup analyses of pivotal trials revealed lower response rates and higher risk of cytokine release syndrome (CRS) in blinatumomab recipients with high pre-treatment tumor (B-ALL) burden. It has therefore been hypothesized that cytoreduction prior to blinatumomab initiation may improve response and reduce risk of severe CRS in patients (pts) with high baseline B-ALL burden. We therefore sought to describe pt and disease characteristics at diagnosis, patterns of pre-blinatumomab cytoreduction, and treatment outcomes in pts with high burden of R/R B-ALL treated with blinatumomab at our institution. Methods: We retrospectively reviewed medical records of adult (≥ 18 years-old) pts with morphologic R/R B-cell ALL (i.e. ≥5% BM blasts and/or radiographically evident EM disease) treated with blinatumomab at Memorial Sloan Kettering Cancer Center (MSKCC) between January 2011 and March 2019 and characterized pts with ≥ 50% bone marrow (BM) blasts by morphology or ≥ 15,000 peripheral blood blasts/µL as having "high-burden" B-ALL. CRS and neurologic toxicity (NTX) were graded per Common Terminology Criteria for Adverse Events v5.0. Objectives included describing cytoreductive therapy given pre-blinatumomab and determining rates of NTX and CRS (any grade and grade ≥3) and morphologic complete response (CR) following 1-2 cycles of blinatumomab. Results: We identified 14 pts with high-burden R/R B-ALL prior to blinatumomab. These pts had a median age of 52 years (range, 23 - 69 years) and median BM blasts of 73% (range, 52 - 〉95%, n=12 pts with evaluable BM). Of these 14 pts, 8 received cytoreductive therapy prior to blinatumomab initiation. Cytoreductive regimens included dexamethasone alone (n=4), cyclophosphamide + dexamethasone (n=2), dexamethasone and vincristine (n=1), or cyclophosphamide + vincristine + dexamethasone (n=1). One pt transitioned to hospice care prior to completing cycle 1 (C1) of blinatumomab and was considered non-evaluable for response. CR was achieved in 6 of the 13 evaluable pts, including 4 of 7 evaluable pts who received cytoreductive therapy and 2 of 6 pts who did not receive cytoreductive therapy. One pt achieved CR in BM but exhibited refractory extramedullary disease. CRS was observed during C1 of blinatumomab in 11/14 pts (grade 1, n=7; grade 2, n=3; grade 3, n=1). The pt with grade 3 CRS had received blinatumomab without cytoreductive therapy. In 4 pts, blinatumomab was temporarily discontinued for management of CRS. NTX of any grade occurred in 4/13 pts during C1, including 1 pt w/grade 3 NTX (depressed level of consciousness), and was reversible in all cases; the pt with grade 3 NTX had full resolution of symptoms following brief interruption of blinatumomab and administration of dexamethasone. Conclusions: Real-world clinical experience with blinatumomab in pts with high-burden B-ALL at a single institution suggested an efficacy and safety profile comparable to what has been reported in the overall population in clinical trials. Compared to published clinical trial experience, rates and severity of CRS following blinatumomab were similar and rates of NTX appeared slightly higher in this small series. Administration of cytoreductive therapy prior to blinatumomab for pts with high-burden B-ALL appears safe, with no additional toxicities. Larger studies will be required to assess whether pts with high-burden B-ALL treated (vs not treated) with cytoreductive therapy prior to blinatumomab exhibit significantly higher rates of CR. Disclosures King: Incyte: Other: Advisory Board; Genentech: Other: Advisory Board ; Astrazeneca: Other: Advisory board. Bolanos:Amgen Inc.: Employment. Velasco:Amgen Inc.: Employment. Tu:Amgen Inc.: Employment. Zaman:Amgen Inc.: Employment. Geyer:Dava Oncology: Honoraria; Amgen: Research Funding. Park:Allogene: Consultancy; Amgen: Consultancy; AstraZeneca: Consultancy; Autolus: Consultancy; GSK: Consultancy; Incyte: Consultancy; Kite Pharma: Consultancy; Novartis: Consultancy; Takeda: Consultancy.

Description: Without a prior history of hemorrhagic disease, a 62-year-old man suffered recurrent episodes of bleeding. Solubility of the patient’s clot in 5 mol/L urea indicated a problem with fibrin stabilization. The transamidase activity potential of factor XIII, measured by the incorporation of radioactive putrescine into N,N-dimethylcasein as test substrate, was 62% of control, close to the normal range of values. Examination of the patient’s clot from recalcified plasma by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that essentially none of the  chains and only about two thirds of the γ chains of fibrin became cross-linked under conditions where both were fully cross-linked in the controls. An antibody to factor XIII was isolated which, although recognizing the recombinant rA2subunits, as well as the virgin A2B2 plasma ensemble, showed a 100-fold greater affinity for the thrombin-activated rA2′ and A2′B2 forms of the zymogen, suggesting that the latter would be its main target during coagulation. Furthermore, the patient’s IgG has an ability, never seen before, for inducing an enzymatically active configuration in the thrombin-activated zymogen in the absence of Ca2+.

Description: INTRODUCTION: In chronic myeloid leukemia (CML) patients in chronic phase (CML-CP), BCR-ABL levels ≤10% at 3 months measured by RT-qPCR (IS) has been consistently correlated with probabilities to obtain an optimal response at 12 months. Monitoring molecular response with automated cartridge-based detection system GeneXpert BCR-ABL (Cepheid®) method has shown an optimal correlation with standardized BCR-ABL (IS) EUTOS method in patients with complete cytogenetic response (CCyR). However, is not known if both methods are also equivalent when measuring BCR-ABL levels above 1%, and therefore, the utility of GeneXpert in order to evaluate response at 3 months must be confirmed. AIMS: To validate the predictive value of molecular response at 3 months with GeneXpert method METHODS: We have studied 125 new consecutive CML-CP patients treated with tyrosine kinase inhibitors (TKIs) followed in 13 centers. Median age at diagnosed was 55 years. The percentage of low, intermediate and high risk Sokal groups were 42%, 40% and 18% . First line treatment was imatinib (IM), nilotinib (NI), dasatinib (DA) or bosutinib (BO) in 58%, 28%, 13% and 1% of the patients, respectively. BCR-ABL level was measured by GeneXpert platform, where all necessary steps to measure BCR-ABL levels are automatically performed. ABL was used as gene control. The study was approved by the Ethics Committee. RESULTS: Median follow up was 43 months. The proportion of patients that achieved CCyR by 12 months, analyzed by intention to treat, was 84% (108/123). Probabilities for each specific TKI were 78%, 93%, 100% and 100% for IM, NI, DA and BO respectively. 23% (96/125) of patients required treatment changed due to resistance or intolerance. Treatment discontinuation probabilities were 32%, 11%, 5% and 0% for IM, NI, DA and BO respectively. Only 4% (5/125) did not achieve an optimal response at 3 months (BCR-ABL ≤10%), which is significant lower compare to results obtain with historical series when using EUTOS IS method. 10% cut-off at 3 month was unable to identify patients that achieved an optimal response in further evaluations. By 12 months, this cutoff did not correlate with probabilities to obtain CCyR (50% vs 86% (p=0.1) or major molecular response (MMR) (60% vs 79% (p=0.21)). In order to find a cutoff that could correlate with optimal response at 12 months, we used a receiver operating characteristic curve to identify the optimal cutoff in transcript level that would allow us to classify the patients as high risk or low risk with maximal sensitivity and specificity for each individual outcome. At 3 months, patients with transcript levels ≤ 1.6% had significantly better probabilities to obtain an optimal response by 12 months, with 81% and 94% sensitivity and specificity for CCyR. With this new cutoff, probabilities for CCyR and MMR at 12 months were 98% vs 54% (p

Description: Activation of the Wnt/β-catenin signaling pathway is a hallmark of a number of solid tumors. We analyzed the regulation of the Wnt/β-catenin pathway in acute lymphoblastic leukemia (ALL) and its role in the pathogenesis of the disease. We found that expression of the Wnt inhibitors sFRP1, sFRP2, sFRP4, sFRP5, WIF1, Dkk3, and Hdpr1 was down-regulated due to abnormal promoter methylation in ALL cell lines and samples from patients with ALL. Methylation of Wnt inhibitors was associated with activation of the Wnt-signaling pathway as demonstrated by the up-regulation of the Wnt target genes WNT16, FZ3, TCF1, LEF1, and cyclin D1 in cell lines and samples and the nuclear localization of β-catenin in cell lines. Treatment of ALL cells with the Wnt inhibitor quercetin or with the demethylating agent 5-aza-2′-deoxycytidine induced an inactivation of the Wnt pathway and induced apoptosis of ALL cells. Finally, in a group of 261 patients with newly diagnosed ALL, abnormal methylation of Wnt inhibitors was associated with decreased 10-year disease-free survival (25% versus 66% respectively, P 〈 .001) and overall survival (28% versus 61% respectively, P = .001). Our results indicate a role of abnormal Wnt signaling in ALL and establish a group of patients with a significantly worse prognosis (methylated group).

Description: Introduction Graft versus host disease (GvHD) is the main cause of morbimortality after allogeneic stem cell transplantation (allo-SCT). Several single-nucleotide polymorphisms (SNPs) in in the promoter region of cytokine genes have shown to alter their expression and are therefore associated with donor-recipient alloreactivity and, ultimately, with SCT outcome. Interleukin 17 (IL-17) is secreted by CD4+ T-cells and has been implicated in the pathogenesis of various autoimmune diseases but its importance in SCT is not well-known. Objective To analyse the influence of IL-17A SNP genotypes on the risk and severity of GvHD and other complications after HLA-identical allo-SCT. Patients and Methods Genomic DNA obtained from peripheral blood samples belonging to 546 patients and their HLA-identical sibling donors (Table 1) included in the DNA Bank of the Spanish Group for Hematopoietic Stem Cell Transplantation (GETH). Genotyping of the polymorphisms of interest, rs8193036 (-737C〉T), rs2275913 (-197G〉A), rs3819024 (-444A〉G), rs4711998 (-877A〉G), were performed by multiplex primer extension followed by mass spectrometry (MALDI-TOF; Sequenom MassArray). Results Genotype frequencies are shown in Table 2 and the association between IL-17A genotypes and complications after allo-SCT are shown in Table 3. Patients transplanted from donors harboring genotype CC for the SNP rs8193036 show increased risk of grade III-IV acute GvHD (7/26 vs 47/397, p=0.035) and of grade II-IV acute GvHD (13/26 vs 133/409, p=0.048). Patients transplanted from donors harboring allele A in the SNP rs4711998 show increased risk of extensive chronic GvHD (53/161 vs 43/177, p=0.045). Relapse rate was not related with IL-17A SNP genotypes. Finally a higher risk of toxicity-related mortality (TRM) was observed in patients transplanted from donors harboring allele A for SNP rs2275913 (78/293 vs 46/227, p=0.048), donors harboring allele G for SNP rs3819024 (78/279 vs 46/242, p=0.011) and donors harboring allele A for SNP rs4711998 (68/250 vs 55/229, p=0.044). Conclusions IL-17A SNP genotyping might be useful to anticipate complications after sibling HLA-identical allo-SCT and, therefore, to improve the clinical management of transplanted patients. This results further support the idea of a genetic predisposition to certain complications after allo-SCT. Paper presented on behalf of the GvHD/Immunotherapy committee of the Spanish Group for Hematopoietic Transplantation (GETH). Disclosures: No relevant conflicts of interest to declare.

Description: Between January 2001 and June 2005 a prospective cohort study of hospitalized patients with hematological malignancies including 47 adults and 30 children with candidemia was conducted at a tertiary oncology care center in Brazil in order to compare the epidemiological characteristics, concurrent illnesses and the clinical microbiological data of both groups that may influence the outcome. The crude mortality was higher in the adult population than in children (46,8% vs. 20,0%) (figure 1). A univariate analysis indicated that in the adult population were lymphoma, neutropenia, presence of comorbidities, a non-removed central venous catheter (CVC), a poor performance status, lack of CVC, use of steroid, hepatic dysfunction, previous surgery, hypotension and severe respiratory dysfunction were risk factors significantly associated with death. Among children the predictors of mortality were acute leukemia, neutropenia, presence of comorbidities, lack of CVC, poor performance status, hypotension, concomitant infected sites, pulmonary infiltrates and severe respiratory dysfunction. Although no major differences was detected in survival rates following fungemia with C. albicans and all Candida non-albicans species, episodes with Candida glabrata, krusei and tropicalis subgroup species had the highest crude death rate compared with C. albicans and other isolates (59,4% vs. 35,3% vs. 10,7%; P

Description: Introduction: Cerebrovascular disease (CVD) is a multifactorial disease caused by the interaction of genetic and environmental factors. The atherosclerotic plaque, the pathological hallmark of CVD, is an inflammatory process, where pro-inflammatory cytokines, such as tumor necrosis factor alpha (TNFα). TNFα secretion shows a high degree of interindividual variability, which is at least partly genetically determined. We have analysed the prevalence of −238 G/A and −308 G/A polymorphisms in the regulatory region of the TNFα gene promoter in CVD. Patients and methods: Genotypic analyses were performed on 308 consecutive unrelated patients diagnosed with ischemic CVD, 147 women and 161 men, mean age 70±0.8 years, who were diagnosed according to the Trial of Org 10172 in Acute Stroke Treatment. All included cases were age and sex matched to a control from the same geographic area who had no history of vascular disease. Patients and controls completed a questionnaires including blood pressure, diabetes status, total serum cholesterol level and smoking history. The TNFα variants were detected by PCR using primers containing a single base-pair mismatch to introduce a restriction site into the wild-type nucleotide sequences after amplification. PCR products were digested with NcoI and MspI to detect −308 and −238 variants, respectively. The strength of the association of the polymorphisms with the occurrence of CVD was estimated by calculation of the OR and its 95%CI by exact method. P values less than 0.05 were considered significant. Logistic regression analysis was applied to estimate the risk in a multivariable predictive model with dependent variable (case/control) and all independent variables significant in the bivariate analysis. SPSS 9.0 was used for the statistical analysis. Results: Genotype analysis showed a significant higher prevalence of the G/A and A/A genotypes of −238 G/A TNFα in patients (p〈 0.01;OR= 2.16;95%CI= 1.40–3.34). The prevalence of the A allele was also significantly increased in the group of CVD patients than in the controls (13.6% vs 7.0%; p

Description: Introduction P210 BCR-ABL translocation resulting from rearrangements within the major breakpoint cluster region (M-BCR), either e13a2 or e14a2, is the molecular hallmark of chronic myeloid leukemia (CML). However, some CML patients may harbor atypical BCR-ABL rearrangements such e1a2 P190 BCR-ABL which involves the minor breakpoint cluster region (m-BCR). Response to therapy with tyrosine kinase inhibitors (TKI) and outcome of such atypical patients is not well defined. Objective To evaluate response to TKI therapy of CML patients with the atypical e1a2 P190 BCR-ABL translocation. Patients and Methods Since 2009, 4 patients with CML in chronic phase and with atypical e1a2 P190 BCR-ABL rearrangement have been recruited in various institutions belonging to the Hematological Molecular Biology Group (GBMH) of the Spanish Society of Hematology (SEHH). Patient characteristics, treatments administered and response to therapy for the 4 patients is shown in Table 1. BCR-ABL transcripts were revealed at diagnosis by quantitative PCR followed by conventional agarose electrophoresis of PCR products. Molecular follow-up of BCR-ABL transcripts throughout treatment was performed by quantitative PCR following the guidelines of the European Leukemia Net. Results One patient received treatment (HU and INF+araC) prior to TKI (Pat. 1; Table 1). All 4 patients received Imatinib as initial TKI treatment. Two of the patients treated with Imatinib (Pat. 1,2) obtained a complete molecular response (CMR) and the other 2 (Pat. 3,4) only achieved a complete hematological response (CHR) as best response (Table 1). All patients had to switch to a second generation TKI (3 Nilotinib and 1 Dasatinib) due to intolerance to Imatinib (n=1; Pat. 1) or resistance (n=3; Pat. 2-4). The patient who received Dasatinib as second line TKI (Pat. 3) only achieved a partial hematologic response (PHR) and was changed to Nilotinib as third line TKI, achieving CHR after which the patient entered in blast crisis and died 36 months after diagnosis (Table 1). Overall, only 1 (Pat. 1) out of the 4 patients included in the present study achieved a sustained molecular response with Imatinib. At last follow-up, among the 4 patients included in the study, all 4 had needed a change of TKI, 1 had died due to disease progression (Pat. 3) and only 2 of them retained a molecular response (Pat. 1,2). Conclusion CML patients harboring atypical e1a2 P190 BCR-ABL transcripts show a poor response and short-lived responses to TKI therapy and therefore should be identified as high-risk patients at diagnosis. These patients must be closely monitored during therapy with TKI and should be treated upfront with a second generation TKI or even be considered for allogeneic SCT in the early phase of the disease. Paper presented on behalf of the Hematological Molecular Biology Group (GBMH) of the Spanish Society of Hematology (SEHH). AJ-V and IB contributed equally to this work. Disclosures: No relevant conflicts of interest to declare.

Description: Abstract 1154 Poster Board I-176 INTRODUCTION Glutathione-S-transferase (GST) M1 and T1 are multifunctional enzymes involved in the metabolism of environmental carcinogens and chemotherapeutic drugs. The immunogenic activity of these enzymes and their association with graft rejection has been widely proved in solid organ transplantation. In this study we examined whether genetic variability (absence versus presence of the gene in donor/recipient pairs) could be related to acute graft versus host disease (aGvHD) in patients undergoing myeloablative allogeneic hematopoietic stem cell transplantation (alloHSCT) from related donor (RD). PATIENTS AND METHODS We evaluated 64 patients with acute leukemia (34 AML and 30 ALL) undergoing alloSCT and receiving myeloablative conditioning (MAC), with a minimum follow-up of 100 days. Donors were HLA-identical siblings in all cases, except in 2 presenting only a single HLA disparity. As source of HSCs, bone marrow progenitors were used in 25 patients (40%) and peripheral blood progenitors in 39 (60%). Total body irradiation (TBI) was used for conditioning treatment in 18 cases (28%). GvHD prophylaxis consisted of a short-term combination of Cyclosporine and Methotrexate. Presence in homozygous or heterozygous (positivity) or absence (negativity) of GSTM1/T1 genes were determined by real-time PCR. A Chi-square test was used to evaluate qualitative variables and non-parametric tests for quantitative variables. The Cox proportional-hazard model was applied to multivariate analysis. RESULTS GSTT1 and GSTM1 positivity was observed in 73 and 47% of patients, respectively, and in 72 and 46% of donors, respectively. Nineteen of 64 patients (30%) presented grade II-IV aGvHD. The incidence of grade II-IV aGVHD in GSTM1-positive patients was 79% versus 21% in GSTM1-negative patients. In univariate analysis, only GSTM1 positive patients developed grade II-IV aGvHD (p=0.001). In multivariate analysis, GSTM1 positivity was the only variable significantly associated with the appearance of grade II-IV aGvHD (p=0.002). No significant association was detected between GSTT1 genetic variability and the incidence of aGvHD. We found no significant difference in patients overall survival in relation to GSTM1 and GSTT1 genetic variability. CONCLUSIONS GSTM1-positive recipients develop more likely grade II-IV aGvHD, independently of other known risk factors. GSTM1 gene determination (homozygous or heterozygous) could be used to assess the aGvHD risk in allogeneic hematopoietic stem cell transplantation. Disclosures No relevant conflicts of interest to declare.

Description: Background Myelodysplastic syndromes (MDS) are a heterogeneous group of malignancies characterized by dysplasia, cytopenia, ineffective hematopoiesis and by an increased risk of transformation to acute myeloid leukemia (AML). Recurrent aberrant karyotypes cannot entirely account for the genetic defects that are at the basis of the pathogenesis of MDS, as they are detected only in approximately 50% of patients. Allogeneic hematopoietic cell transplantation (HCT) likely prolongs survival in patients with AML and MDS. In this report, we evaluated the impact of presence of dyspoesis in paients with AML with or without cytogenetic (CG) abnormality on outcome in our center. Methods We retrospectively reviewed all patients who were diagnosed with AML (non promyelocytic) in our center between 2002 and 2012. Primary objective was to study the impact of MDS with or without CG abnormalities on outcome of patients with AML. Demographics and disease-related variables were collected. OS was defined as the time from diagnosis to the time of death or last contact. Results Between 2002 and 2012, 123 patients with high or intermediate risk AML patients were treated at our center. Median age at diagnosis was 60 (range 19-89). Median OS for all patients was 368 days. Of 123 patients, 51 had MDS while 73 did not. CG abnormalities were present in 35 (68%) of patients with dyspoetic changes. Median age of AML patients with MDS was 59 while median age of AML without MDS patients was 55. Median number of blasts in bone marrow and peripheral blood in AML patients with MDS was 38% and 6% respectively. While median number of blasts in bone marrow and peripheral blood in AML patients without MDS was 67% and 39% respectively. Of 51 AML patients with MDS, 14 received HCT with median age of 56. Half of these received myeloablative regimen while the other half received reduced toxicity regimen. The median survival time for AML patients without MDS was 401 days while the median survival time for AML patients with MDS was 278 days (p = 0.0201), Fig1. For AML with MDS who received HCT, the median survival time was 586 days while it was 164.5 days for AML patient with MDS who did not receive HCT (p = 0.0013), Fig2. Conclusion In this small cohort from a single center, the results suggest that AML patients with dyspoetic changes do have a worse prognosis despite having lower percentage of blasts in bone marrow or peripheral blood. This can be explained by what Walter et al reprted, using next-generation sequencing, that the proportion of neoplastic marrow cells is indistinguishable in MDS and secondary-AML even with myeloblast count of zero. HCT can be performed in those patients including older patients with promising results. Disclosures: No relevant conflicts of interest to declare.