ABSTRACT:Relapse after remission remains the primary cause of treatment failure in acute myeloid leukemia (AML), underscoring the need for strategies to eliminate residual leukemic cells. The bone marrow (BM) microenvironment, largely orchestrated by the CXC chemokine receptor 4 (CXCR4)-CXC motif chemokine 12 axis (CXCL12), enables leukemia cell survival and chemoresistance by anchoring blasts in their protective BM niche. Motixafortide, a selective CXCR4 antagonist, mobilizes leukemic cells and disrupts tumor microenvironment interactions in preclinical models. In this randomized, double-blind, placebo-controlled phase 2 trial, 128 patients in first remission received high-dose cytarabine plus motixafortide or placebo. Median relapse-free survival did not substantially differ between groups: 10.3 months (95% confidence interval [CI], 8.0-12.0) for motixafortide and 11.5 months (95% CI, 8.6-24.1) for placebo (log-rank P = .98). But single-cell measurable residual disease (scMRD) analysis, performed before consolidation, demonstrated heterogeneity of CXCR4 inhibition benefit; in the placebo group, higher CXCR4 expression was associated with increased relapse risk (P = .02), whereas in the motixafortide group, higher CXCR4 expression was linked to a reduced relapse rate (P = .047). Exploratory analyses identified scMRD levels at which higher MRD burden was associated with inferior overall survival. Taken together, combining functional MRD profiling with biomarker-driven patient selection, such as CXCR4 expression, may enable more precise and effective postremission interventions in AML. This trial was registered at www.clinicaltrials.gov as NCT02502968 and at EudraCT as 2014-002702-21.

PURPOSE First-line therapy options in advanced cholangiocarcinoma (CCA) are based on the ABC-02 trial regimen (gemcitabine/cisplatin [G/C]). The NIFE trial examined nanoliposomal irinotecan/fluorouracil/leucovorin (nal-IRI/FU/LV) as alternative first-line therapy in advanced CCA. METHODS NIFE is a prospective, open-label, randomized, multicenter phase II study that aimed at detecting efficacy comparable with the standard treatment. Patients with advanced CCA were randomly assigned (1:1) to receive nal-IRI/FU/LV (arm A) or G/C (arm B). Stratification parameters were intrahepatic versus extrahepatic CCA, sex, and Eastern Cooperative Oncology Group (ECOG; 0/1). Arm A was designed as a Simon's optimal two-stage design and arm B served as a randomized control group. The primary goal was to exclude an inferior progression-free survival (PFS) at 4 months of only 40%, while assuming a rate of 60% on G/C population. RESULTS Between 2018 and 2020, overall 91 patients were randomly assigned to receive nal-IRI/FU/LV (n = 49) or G/C (n = 42). The NIFE trial formally met its primary end point with a 4-month PFS rate of 51% in patients receiving nal-IRI/FU/LV. The median PFS was 6 months (2.4-9.6) in arm A and 6.9 months (2.5-7.9) in arm B. Median overall survival (OS) was 15.9 months (10.6-20.3) in arm A and 13.6 months (6.5-17.7) in arm B. The exploratory comparison of study arms suggested a numerical but statistically not significant advantage for nal-IRI/FU/LV (hazard ratio for PFS, 0.85 [95% CI, 0.53 to 1.38] and for OS, 0.94 [95% CI, 0.58 to 1.50]). Analysis for stratification parameters revealed no differences for sex and ECOG, but for tumor localization. The objective response rate was 24.5% with nal-IRI/FU/LV and 11.9% with G/C. No unexpected toxicities occurred. AEs related to nal-IRI/FU/LV were mainly GI and to G/C hematologic. CONCLUSION Treatment of advanced CCA with nal-IRI/FU/LV demonstrated efficacy in first-line therapy without new safety findings and merits further validation.

A randomized inter-group trial comparing more intensive treatment strategies to a common standard arm 3 + 7 (CSA) was conducted in patients with non-M3 AML. Untreated patients ≥ 60 years were allocated to the CSA (n = 132) or to the study group arms (n = 1154) of the AMLCG (TAD/HAM versus HAM/HAM ± G-CSF followed by TAD and maintenance) and the OSHO (intermediate-dose ara-C/mitoxantrone followed by ara-C/mitoxantrone). Median age of the 1147 eligible patients was 69 (range 60–87) years. CR/CRi status at 90 days was not significantly different between the CSA (54

Background: Leukemia-cell-stroma interactions are an attractive therapy target in AML. The CXC chemokine receptor 4 (CXCR4) and its ligand CXCL12 (SDF-1) are expressed and secreted by myeloid leukemia blasts and play an essential role in the migration, homing, differentiation, proliferation, and retention of myeloid blasts within the protective bone marrow (BM) niche. The high-affinity CXCR4 antagonist BL-8040 is directly toxic for AML blasts and interrupts the interaction between blasts and the protective BM microenvironment. Objective: The aim of this clinical trial was to evaluate the impact of BL-8040 in combination with standard consolidation therapy on relapse free survival (RFS) in patients with acute myeloid leukemia (AML) in first complete remission (CR, CRp, CRi). Methods: Adult patients ≥ 18 years with documented 1st CR/CRi/CRp, after induction therapy with cytarabine and an anthracycline, and not scheduled for allogeneic stem cell transplantation were randomized in a 1:1 ratio to receive two cycles (≥ 60 years) or three cycles (<60 years) of high-dose cytarabine plus BL-8040 or placebo as consolidation therapy. The dosage of cytarabine was 1g/m² per dose for subjects older than 60 years and 3 g/m² per dose for subjects younger than 60 years. Results: Between November 2015 and November 2019, 134 patients of the originally planned number of 202 were recruited at 29 trial sites, 6 patients violated inclusion and/or exclusion criteria and were excluded. Considering the results of the interim analysis, the data monitoring committee recommended to stop recruitment. Thus, no further patients were enrolled. One hundred and twenty-eight patients were randomized (63 placebo; 65 BL-8040). Baseline characteristics were balanced between treatment arms: median age 61 vs 63 years; 2010 ELN favorable or intermediate-risk 95% vs 98%; CXCR4 expression 38% vs 30% in the BL-8040 and standard arm, respectively. Overall median follow-up time was 25.4 months. Median RFS was similar between arms 10.3 months [95% CI 8.0,12.0] for the BL-8040 arm and 11.5 months [95% CI 8.6,24.1] for the placebo arm (two-sided p=0.98 by log-rank test).The median OS was not reached at the time point of the analysis. Intention to treat (ITT) analyses revealed no difference between placebo and BL-8040, neither for the total cohort, nor for the subset of patients with expression of CXCR4 with respect to RFS (Hazard ratio (HR) 1.0, 95% CI 0.7,1.6, p =0.9, and HR 0.9, 95% CI 0.1,2.9, p =0.9,respectively) or overall survival (OS; HR 1.1, 95% CI 0.6,2.0, p = 0.8, and HR 2.5, 95% CI 0.4,13.8, p = 0.3, respectively). Regarding safety endpoints, overall, 739 and 576 adverse events were documented in the BL-8040 and placebo arm, respectively. Serious adverse events were similar between therapies. Conclusion: The addition of BL-8040 to intensive consolidation therapy did not improve RFS or OS. Although more side effects were noted, no differences in serious adverse events were observed.

e18501 Background: HSCT has been reported to be a treatment option for elderly patients with AML. Here we analyze the outcome of CT compared to HSCT in elderly AML patients according to genetic risk groups defined by the European Leukemia Net. Methods: By May 2015, 492 of 789 eligible patients (62%) from the AML 2004 study group entered CR and were assigned to CT (n = 205), matched (n = 119) or one antigen/allele mismatched HSCT (n = 31) depending on donor availability. Median age was higher (68 vs 66 years; p < 0.0005) and intermediate risk (IR) II and high risk (HR) cytogenetics were less frequent (p = 0.002) in CT than in HSCT. The interval CR - CT was significantly shorter than CR - HSCT (43 vs 65 days; p < 0.0005]. AML type, NPM1 and FLT3 status were comparable. Results: Patients receiving matched HSCT had longer LFS than those receiving CT (25±5% vs. 14±3% at 9 years; p < 0.001). As expected, RI was lower (42±5% vs 78±3%; p < 0.0001) and NRM was higher (34±5% vs 8±2%; p < 0.0001) at 9 years in HSCT than in CT patients. LFS differed between HSCT and CT for IR I (28±8% vs. 16±4% at 9 years; p = .007), IR II (30±10% vs. 4±4% at 7 years; p = .08) and HR patients (12±7% vs. 0±0% at 7 years; p < .05). RI was decreased in HSCT vs. CT for IR I (35±7% vs. 74±4% at 9 years; p < .0001), IR II (38±10% vs. 96±5% at 7 years; p < .0001) and HR (59±11% vs. 96±7% at 9 years; p < .004). These effects outweigh the higher NRM in HSCT for IR I (37±9% vs. 10±3% at 9 years; p = .0005), IR II (33±10% vs. 0% at 7 years; p = .003) and HR (29±10% vs. 4±4% at 9 years; p = .11). HSCT was an independent prognostic factor for NRM (p < 0.005), LFS and RI (both p < 0.0005). Genetic risk group (p < 0.01) was the only factor associated with OS. Conclusions: HCT improves LFS in AML CR1 patients between 60 and 75 years of age in genetic risk groups from IR I to HR. Clinical trial information: NCT01497002.

Abstract Background The German AML Intergroup conducted two randomized studies in younger (<60 years) and elderly (≥60 years) patients in which the study arms were compared to a common standard arm. Here, we compared the two studies in younger and elderly patients focusing on disease characteristics and outcome. Patients and Methods The East German Study Group (OSHO) and the Acute Myeloid Leukemia Cooperative Group (AMLCG) each entered patients from 18 to 59 years into one study and patients aged 60 years and older into another. Each study group randomized upfront 10% of all AML patients into a common standard arm and 90% in the study group specific arm. All patients with de novo AML or AML after myelodysplastic syndrome or cytotoxic treatment were eligible. Chi-squared and Mann-Whitney-U tests were used to detect significant differences between the age groups regarding demographic, clinical and cytogenetic characteristics at baseline. Complete Remission (CR) at 90 days and cumulative probabilities of death were determined for outcome. To avoid bias due to the higher probability of death in older patients, cumulative probabilities of death were calculated for relapsed patients or those who did not achieve CR after 90 days. Other deaths were considered as a competing risk. Results A total of 2435 AML patients were analyzed, 1132 in the study <60 years and 1303 in the study ≥60 years. Significant differences in patient characteristics were noted between the studies. The elderly patient group contained a higher proportion of males than the younger group (55% vs 49% respectively, p=0.0031) and a higher percentage of secondary AML (40% vs 21% respectively, p<0.0001). In contrast, younger patients had higher median WBC count [13x109/L (range 0.03-798) for <60 years and 6.9x109/L (range 0.23-450) for ≥60 years, p<0.0001] and higher median lactate dehydrogenase [442U/L (range 35-19,624) for <60 years and 350U/L (range 51-9,486) for ≥60 years, p<0.0001]. Cytogenetic risk was similarly distributed in both groups (favorable: 12% in both age groups, intermediate: 66% in <60 years and 63% in ≥60 years, adverse: 22% in <60 years and 25% in ≥60 years, p=0.1672). However, the favorable combination of FLT3-ITDwt and NPM1mut in normal karyotype was more common in the younger (35%) than in the older group (27%; p=0.0212). A higher rate of CR at 90 days was observed in the younger (66%) than in the older (51%) patients (p=<0.0001). Of the younger patients 14.8% died (3.8% with persisting AML, 3.3% without AML and 7.7% without evaluable disease status) while of the older patients 21.8% died (6.2% with persisting AML, 2.5% without AML and 13.1% without evaluable disease status) during this period (p=0.0001). Relapse at 90 days was seen in 1% of the younger and in 2% of the older patients. The cumulative probability of AML-related death was lower in younger patients than in older patients (p<0.0001). Of the younger patients 29% (95% CI: 26% to 31%) and 44% (95% CI: 40% to 46%) died after one and three years due to AML; in the older group the corresponding frequencies were 45% (95% CI: 42% to 48%) and 62% (95% CI: 59% to 65%; Figure 1a). The probability of dying from AML was lowest for the younger patients with de novo AML [27% (95% CI 24% to 29%) at 1 year and 41% (95% CI 38% to 44%) at 3 years] and highest for those with secondary AML [38% (95% CI 32% to 44%) at 1 year and 56% (95% CI 49% to 62%) at 3 years (p=0.0001)], with similar differences being observed in the older patients (p=0.0001, Figure 1b). In the younger patients, CR at 90 days was lower in the standard (58%) than in the study arm (66%, p=0.0558), while AML related death was 29% and 27% at 1 year and 44% and 39% at 3 years respectively. In the older patients CR at 90 days was 52% vs. 51%, AML related death at 1 year 45% and 45% and at 3 years 63% and 69% for study arm and standard arm, respectively (Figure 1c). Conclusion This analysis reveals significant differences in gender, laboratory characteristics and proportion of secondary AML in elderly compared to younger AML patients. While there was no clear difference in cytogenetic risk groups, favorable molecular markers were more frequent in younger patients. Clear differences in CR rates after 90 days of therapy and AML related death rate were seen in regard to age (<60 years and ≥60 years) and disease type (de novo and secondary AML). As the common standard arm in both of the studies was age adapted, the differences between the two age groups are likely to be related to disease biology. Disclosures Niederwieser: Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Hoffmann:Novartis Oncology Europe: Research Funding. Krug:Sunesis; Clavis Pharma; usa Pharma, Catapult Cell Therapy, Gilead, Roche: Membership on an entity's Board of Directors or advisory committees; Sunesis: Speakers Bureau; Boehringer Ingelheim: Research Funding; Novartis; BMS; Roche; Boehringer Ingelheim; Bayer: Honoraria. Hegenbart:Janssen: Honoraria, Other: travel support. Pfirrmann:Novartis Pharma: Consultancy, Honoraria; BMS: Consultancy, Honoraria. Kraemer:TEVA: Other: travel support. Al-Ali:Celgene: Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding.

Background Preoperative chemoradiotherapy with infusional fluorouracil, total mesorectal excision surgery, and postoperative chemotherapy with fluorouracil was established by the German CAO/ARO/AIO-94 trial as a standard combined modality treatment for locally advanced rectal cancer. Here we compare the previously established regimen with an investigational regimen in which oxaliplatin was added to both preoperative chemoradiotherapy and postoperative chemotherapy.Methods In this multicentre, open-label, randomised, phase 3 study we randomly assigned patients with rectal adenocarcinoma, clinically staged as cT3-4 or any node-positive disease, to two groups: a control group receiving standard fluorouracil-based combined modality treatment, consisting of preoperative radiotherapy of 50.4 Gy in 28 fractions plus infusional fluorouracil (1000 mg/m(2) on days 1-5 and 29-33), followed by surgery and four cycles of bolus fluorouracil (500 mg/m(2) on days 1-5 and 29); or to an investigational group receiving preoperative radiotherapy of 50.4 Gy in 28 fractions plus infusional fluorouracil (250 mg/m(2) on days 1-14 and 22-35) and oxaliplatin (50 mg/m(2) on days 1, 8, 22, and 29), followed by surgery and eight cycles of oxaliplatin (100 mg/m(2) on days 1 and 15), leucovorin (400 mg/m(2) on days 1 and 15), and infusional fluorouracil (2400 mg/m(2) on days 1-2 and 15-16). Randomisation was done with computer-generated block-randomisation codes stratified by centre, clinical T category (cT1-3 vs cT4), and clinical N category (cN0 vs cN1-2) without masking. The primary endpoint was disease-free survival, defined as the time between randomisation and non-radical surgery of the primary tumour (R2 resection), locoregional recurrence after R0/1 resection, metastatic disease or progression, or death from any cause, whichever occurred first. Survival and cumulative incidence of recurrence analyses followed the intention-to-treat principle; toxicity analyses included all patients treated. Enrolment of patients in this trial is completed and follow-up is ongoing. This study is registered with ClinicalTrials.gov, number NCT00349076.Findings Of the 1265 patients initially enrolled, 1236 were assessable (613 in the investigational group and 623 in the control group). With a median follow-up of 50 months (IQR 38-61), disease-free survival at 3 years was 75.9% (95% CI 72.4-79.5) in the investigational group and 71.2% (95% CI 67.6-74.9) in the control group (hazard ratio [HR] 0.79, 95% CI 0.64-0.98; p=0.03). Preoperative grade 3-4 toxic effects occurred in 144 (24%) of 607 patients who actually received fluorouracil and oxaliplatin during chemoradiotherapy and in 128 (20%) of 625 patients who actually received fluorouracil chemoradiotherapy. Of 445 patients who actually received adjuvant fluorouracil and leucovorin and oxaliplatin, 158 (36%) had grade 3-4 toxic effects, as did 170 (36%) of 470 patients who actually received adjuvant fluorouracil. Late grade 3-4 adverse events in patients who received protocol-specified preoperative and postoperative treatment occurred in 112 (25%) of 445 patients in the investigational group, and in 100 (21%) of 470 patients in the control group.Interpretation Adding oxaliplatin to fluorouracil-based neoadjuvant chemoradiotherapy and adjuvant chemotherapy (at the doses and intensities used in this trial) significantly improved disease-free survival of patients with clinically staged cT3-4 or cN1-2 rectal cancer compared with our former fluorouracil-based combined modality regimen (based on CAO/ARO/AIO-94). The regimen established by CAO/ARO/AIO-04 can be deemed a new treatment option for patients with locally advanced rectal cancer.

Treatment of elderly patients with AML remains challenging. While increasing doses of induction and consolidation chemotherapy have failed to improve outcome, efforts to decrease relapse rates using the graft-versus-leukemia effect have shown promising results in phase II studies. In the present analysis of the prospective OSHO 2004 study we evaluated the effect of post-induction hematopoietic cell transplantation (HCT) in comparison to conventional consolidation chemotherapy (CT) on outcome in elderly patients with AML.

Abstract The optimal consolidation chemotherapy in AML patients >60 years has yet to be defined in detail. Although age-adjusted induction chemotherapy results in CR rates comparable to those in younger patients, relapse remains the major hurdle to successful treatment. While the role of stem cell transplantation (HSCT) in elderly patients is currently being evaluated in randomized studies, we focus here on the intensity of consolidation chemotherapy. Patients data from the elderly AML trials OSHO 1997 (n=410) and OSHO 2004 (n=733) were pooled and analyzed. These protocols have identical inclusion/exclusion criteria and induction chemotherapy, but differ in the intensity of consolidation therapy. In the OSHO 1997 trial, Ara-C 120 mg/m2 bid was given from day 1-5 and mitoxantrone 10 mg/m2 from day 1-2 as consolidation. In the OSHO 2004 an intensified consolidation using Ara-C 500 mg/m2 bid on day 1/3/5 was applied together with mitoxantrone as used in the OSHO 1997 study. Of the 1143 patients, 689 entered CR (60% in the OSHO 1997 and 61% in the OSHO 2004) and 536 (OSHO 1997, n=242, OSHO 2004, n=294) did not receive HSCT as consolidation. The analysis concentrated on the dose of AraC used in the consolidation for this elderly population and on the cycles of consolidation applied. Patient characteristics were compared using chi-square test for categorical data and Wilcoxon rank sum test for continuous data. OS was analyzed using the Kaplan-Meier method, and univariate comparisons were made by means of the log-rank test. Cox regression was used to find any association between consolidation chemotherapy considered as a time-dependent covariate on Overall Survival (OS) or Relapse Incidence (RI). RI and Non Relapse Mortality (NRM) were calculated using the competing risk method, and the Gray test was applied to compare differences. Multivariate modeling was performed by Cox regression analyses with a forward selection method. Median ages in the AML studies were 66 (60-81) years and 69 (60-85) years for the OSHO 1997 and OSHO 2004, respectively. Patients characteristics were balanced except for age and Karnofsky score (p< .0005) and a trend towards more intermediate and high risk karyotypes, more female and less WBC in the OSHO 2004 compared to the OSHO 1997 study (p=0.06). OS at 15 years was 14±2% in all patients with no difference between the two consolidations, but strong dependence on cytogenetic risk factors. In multivariate analyses risk factors for survival were high/intermediate risk karyotypes, male gender, non de-novo AML and less than two consolidations. Patients with two consolidations had better OS than patients with one or no consolidations in the pooled group and in each of the two protocols with no difference between OSHO 1997 and OSHO 2004. Relapse incidence amounted to 79±2% and NRM 10±04% at 15 years with no difference between the two protocols. Relapse incidence was dependent upon cytogenetic risk and the number of consolidations applied in a multivariate model. There were no risk factors predicting TRM in multivariate analysis. Our analysis of patient characteristics according to the number of consolidations showed the distribution of consolidation therapies to be 15.2%, 28.0%, 56.6% and 14.2%, 32.3% and 53.4% for 0, 1 and 2 consolidations in the OSHO 1997 and OSHO 2004 respectively (n.s.). Higher age, higher risk cytogenetics, non-de novo AML type, less CR after one induction cycle and lower WBC count at diagnosis were characteristic of patients receiving none or one as compared to two consolidation therapies. The multivariate analysis revealed cytogenetics and gender as independent risk factors, but not the application of one as opposed to two consolidation treatments. The increase of AraC dose in the OSHO 2004 was unable to either increase survival or improve relapse incidence in the cohort of elderly patients. TRM was not different between the OSHO 1997 and 2004 studies. However, the application of one or two consolidation cycles had a significant impact on survival that was not due to decreased relapse incidence after normalization for risk factors. Interestingly, just above 50% of patients received 2 consolidations as proposed in the protocol with no statistically significant difference between OSHO 1997 and OSHO 2004. Patients receiving fewer consolidation therapy cycles are older, have more non-de novo AML and lower WBC count. Disclosures: Hochhaus: Novartis: Consultancy, Honoraria, Research Funding, Travel Other; BMS: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria; Ariad: Consultancy, Honoraria.

![Graphic][1] Purpose In patients with relapsed acute myeloid leukemia (AML) > 60 years of age we analyzed age at relapse, interval from first complete remission (CR1) to relapse, cytogenetic risk at initial diagnosis, prior allogeneic stem cell transplantation (alloSCT) and FLT3/NPM1 mutational status as possible prognostic factors for overall survival (OS). Introduction After achieving CR1 more than 50% of elderly AML patients eventually relapse. Prognostic factors for OS are poorly defined in this patient population. For younger patients with relapsed AML a risk score has been described including age at relapse, interval from CR1 to relapse, cytogenetic risk at initial diagnosis and prior stem cell transplantation (SCT) as prognostic factors. We sought to investigate whether these are also prognostic factors in elderly patients with relapsed AML. In addition, we assessed the prognostic impact of FLT3- and NPM1 mutational status (wild-type (wt) or mutated (mut)) at diagnosis. Patients and methods In the ongoing multicenter OSHO trial #69 for AML patients > 60 years we evaluated data of all relapsed patients. Overall survival was calculated from the day of first relapse until the day of death using the Kaplan Meier method. Univariate analysis was performed to test for the influence of age at relapse, interval from CR1 to relapse, cytogenetic risk at initial diagnosis, prior alloSCT and FLT3/NPM1 mutational status. Subsequently, independent prognostic factors were defined in a multivariate analysis with age at relapse, time from CR1 to relapse, cytogenetic risk at initial diagnosis and prior alloSCT as covariates. Results From April 2005 until April 2013 904 patients were registered. 733 of these received intensive induction chemotherapy which resulted in CR1 in 447 (61%) pts. In this patient group 260 relapses were observed after a median interval, calculated from the day of CR1, for living patients of 2.7 years (range 0.1 to 7.5). Median age at relapse was 69 years (range 60 – 85) with 129 (49.6%) pts. being 60 to 68 years old, 102 (39.2%) pts. being 69 to 74 years old and 29 (11.1%) pts. being 75 to 85 years old. Median interval from CR1 to relapse was 0.58 years (0.07 – 6.28). 114 (43.8%) relapses occurred up to 6 months after CR1, 119 (45.8%) between 7 and 18 months after CR1 and 27 (10.4%) later than 18 months after CR1. Only five (1.9%) relapsed pts. showed good risk cytogenetics at diagnosis, whereas it was of intermediate risk in 159 (61.1%) pts., of poor risk in 68 (26.2%) pts. and unknown in 28 (10.8%) pts. Forty-one (15.8%) pts. had received prior alloSCT in CR1. Information on FLT3- and NPM1 mutational status at diagnosis was available in 194 (74.6%) pts. 110 (42.3%) pts. had FLT3/NPM1 wt/wt, 48 (18.5%) pts. had FLT3/NPM1 wt/mut, 23 (8.8%) pts. had FLT3/NPM1 mut/wt and 13 (5.0%) pts. had FLT3/NPM1 mut/mut. OS rate at 2 years of all relapsed pts. was 13 ± 2%. For patients younger than 69 years and for those 69 years of age or older OS rate at 2 years was 17 ± 4% and 9 ± 3%, respectively (p=0.03). The interval between CR1 and first relapse also affected 2 year-OS with 7 ± 3%, 15 ± 4% and 36 ± 12% for pts. with relapse up to 6 months, 7 to 18 months and later than 18 months after CR1, respectively ( 18 months: p=0.009). OS rate at 2 years was also influenced by cytogenetic risk at initial diagnosis with 17 ± 3% for pts. having good or intermediate risk cytogenetics and 3 ± 2% for those with poor risk cytogenetics (p< 0.0005). Prior alloSCT had a negative influence on OS. Two-year OS rate was 10 ± 5 and 13 ± 3% (p= .015) for patients with prior alloSCT vs. those without prior alloSCT, respectively. FLT3/NPM1 mutational status at diagnosis had no impact on OS. In univariate analysis age at relapse (p<0.04), interval from CR1 to relapse (p< 0.0005), cytogenetic risk at initial diagnosis (p<0.02) and prior alloSCT (p<0.02) were shown to be prognostic factors for OS, whereas FLT3/NPM1 mutational status was not significant (p=0.82). In multivariate analysis the same factors remained significant but only interval from CR1 to relapse (p<0.0005) and prior alloSCT (p=0.003) were independent. Conclusion In AML patients >60 years in first relapse OS is poor. Longer interval from CR1 to relapse and no prior alloSCT are independent beneficial prognostic factors for OS. FLT3/NPM1 mutational status at diagnosis has no prognostic impact on OS. Disclosures: Wedding: Roche: Speakers Bureau; Amgen: Speakers Bureau; Chugai: Speakers Bureau; Janssen-Cilag: Speakers Bureau; Novartis: Speakers Bureau; Cephalon: Speakers Bureau; Prostarkan: Speakers Bureau; Pfizer: Speakers Bureau. Niederwieser: Novartis: Consultancy. [1]: /embed/inline-graphic-1.gif

4033 Background: Treatment of patients (pts) with advanced pancreatic cancer (APC) is often complicated by venous thromboembolic events (VTE). Anticoagulation therapy with low molecular weight heparin (LMWH) Enoxaparin (E) prevents VTE in APC and is under discussion to improve overall survival (OS) in cancer pts. Methods: Calculation was based on an expected reduction of the primary endpoint symptomatic VTE (sVTE) within the first 3 months (m) of treatment from 10% to 3%. Time to progression (TTP) and OS were among the secondary endpoints of the study. Chemotherapy naive pts with histologically or cytologically confirmed APC were randomized to receive (E) or not (O) to receive additional LMWH (E:1 mg/kg once daily for 3 m, followed by 40 mg/d) simultaneous to palliative systemic chemotherapy. Results: From Apr 2004 to Jan 2009 312 (O: 152/ E: 160) pts were recruited. ITT demonstrate significant decreases in sVTE after 3 m (O: 9.87%; E: 1.25%) and 12 m (O: 15.13%; E: 5.00%). Treatment was well tolerated and showed no significant differences in major bleeding. After a median follow up of 45.44 m TTP (O: 5.42 m; E: 5.03 m; p = 0.941) and OS (O: 7.98 m; E: 8.28 m; p = 0.501) are not different. Prespecified analysis excluding pts with sVTE showed no significance in OS (O: 8.15 m; E: 7.92 m; p = 0.054). Conclusions: Enoxaparin is effective and safe in the primary prevention of sVTE applied simultaneously with cytotoxic chemotherapy in pts with APC but does not prolong TTP or OS. No significant financial relationships to disclose.

LBA4506 Background: The course of pts with APC is often complicated by venous thromboembolic events (VTE). Anticoagulation therapy with LMWH may prevent VTE and is under discussion to improve overall survival (OS) in cancer. Based on our previous pilot study (Hilbig et al, Onkologie 2005;28(suppl 3)) indicating the safety and feasibility to the addition of the LMWH enoxaparin to chemotherapy in pts with APC we started the open, prospective, randomized, multicenter study to investigate the role of enoxaparin in these pts. Methods: Primary endpoint was the reduction of symptomatic VTE (sVTE) from an expected 10% to 3% within the first 12 weeks of treatment. The occurrence of sVTE (secured by an independent, blinded event review board) in 24 pts was calculated to be necessary in order to define the role of enoxaparin in decreasing the risk of VTE. Toxicity, time to progression (TTP), and OS were among the secondary endpoints of the study approved by the ethics committees of the participating centers. VTE-naive and chemotherapy-naive pts with histologically or cytologically confirmed APC were randomized to receive or not to receive additional LMWH (enoxaparin 1mg/kg once daily) starting in parallel to palliative systemic chemotherapy. Results: In January 2009 after recruitment of 312 pts the study was closed. There were 22 sVTE in 152 pts of the observation group (O) and 8 in 160 pts of the enoxaparin group (E). ITT and PP analyses demonstrated significant risk reductions from 14.5% to 5.0% (65% RRR) and 14.5% to 3.8% (74% RRR) for E, respectively. Major bleeding events were 9.9% for O and 6.3% for E (ITT; n.s.). In each group there was one tumor-related fatal hemorrhage. Preliminary data show no difference in TTP (O:19 vs. E:22 w) and OS (O:29 vs. E:31 w). Conclusions: Enoxaparin is effective and safe in the primary prevention of sVTE applied in parallel with cytotoxic chemotherapy in pts with APC. Final results on TTP and OS are pending. No significant financial relationships to disclose.

BACKGROUND:Advanced pancreatic cancer, in addition to its high mortality, is characterized by one of the highest rates of venous thromboembolic events (VTE) as compared to other types of cancer. Enoxaparin, a low molecular weight heparin (LMWH), has proven to be effective for the prevention and treatment of VTE in surgical and general medical patients. Results of some small studies suggest that this benefit might extend to patients with cancer, however, enoxaparin is not currently indicated for this use. This phase IIb study was designed to analyze the efficacy of enoxaparin in patients with locally advanced or metastatic pancreatic cancer undergoing systemic chemotherapy.METHODS:The aim of this prospective multicenter trial is to compare concomitant treatment with enoxaparin to no anticoagulation in 540 patients. Primary endpoint is the incidence of clinically relevant VTE (symptomatic deep venous thrombosis (DVT) of the leg and/or pelvic and/or pulmonary embolism (PE)) within the first 3 months. Secondary endpoints include the incidence of symptomatic and asymptomatic VTE after 6, 9 and 12 months as well as remission at 3, 6, 9 and 12 months, overall survival and bleeding.TRIAL REGISTRATION:isrctn.org identifier CCT-NAPN-16752, controlled-trials.com identifier: ISRCTN02140505.RESULTS:An interim analysis for safety performed after inclusion of 152 patients revealed no increased risk of bleeding (5 pts vs. 6 pts, Chi2: 0.763).CONCLUSION:PROSPECT is a pivotal study in elucidating the role of low molecular weight heparins in advanced pancreatic cancer. Its results will lead to a new understanding of the role of heparins in the prevention of venous thromboembolism and of their effect on survival, remission rates and toxicity of chemotherapeutic regimens.