Citations

Abstract Abstract 2692 Background: Massive splenomegaly is occasionally encountered in patients with Non-Hodgkin's Lymphoma (NHL) and can be associated with abdominal symptoms, anemia and thrombocytopenia. The spleen may also be a primary focus of the disease itself. Splenectomy offers the benefit of localized treatment of the disease as well as relief of symptoms from splenomegaly and associated cytopenias. The safety and long term clinical outcomes of splenectomy for massive splenomegaly (>1500 gm) in patients with various histologies of NHL was analyzed. Methods: Data was obtained from clinical records of 90 patients with a diagnosis of NHL who underwent a splenectomy at Mayo Clinic Rochester from January 1998 to December 2007. Demographics, previous treatments, histology, post- surgical complications were collected and analyzed for the entire cohort. Additionally, median overall survival, improvement in symptoms, anemia and thrombocytopenia were analyzed by NHL type. Results: Median age at splenectomy was 67 years (range 42–84 yrs.) and 56 (62%) of patients were male. Average time from diagnosis to splenectomy was 3 months (range 0–217 months). Splenectomy was the first treatment in 56 (62%) patients; the other 34 patients were treated with chemotherapy with an average of two previous regimens. Most patients had involvement outside of the spleen, 65 (72%) with concurrent bone marrow involvement and 35 (50%) with lymph node involvement. Various different NHL histologies were represented: marginal zone (MZ) (34%), mantle cell (MC) (26%), diffuse large B-cell lymphoma (DLBCL) (10%), follicular (FL) (11%), lymphoplasmacytic (LP) (6%) and T cell NOS (4%). With a median follow-up time of 25 months, the median overall survival differed by histology type of NHL (Table 1). Indolent lymphomas such as FL, LP and MZ had more favorable survival compared with more aggressive lymphomas such as DLBCL and T cell NOS. Splenectomy was safe and well tolerated with only one treatment related death. There were no reported post-splenectomy septic events. Two patients did develop a portal vein thrombosis. 95% of patients had relief in pressure and abdominal symptoms post-splenectomy. With the exception of patients with DLBCL and T-cell NHL, a majority of patients had improvement in anemia and thrombocytopenia related to splenomegaly (Table 2). Conclusions: This represents the largest reported series of patients with lymphoma treated with splenectomy. Our results indicate that median overall survival after splenectomy is determined by the underlying type of NHL. Patients with LP, FL, MZ and MCL have a favorable outcomes following splenectomy. Splenectomy remains a safe and effective treatment option for massive splenomegaly in selected patients during the course of their disease management. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3405 Poster Board III-293 Background: Autologous hematopoietic cell transplantation (AutoHCT) as consolidation has been an alternative to standard intensive chemotherapy and/or allogeneic HCT for younger patients with acute myeloid leukemia (AML) in first complete remission (CR). However concerns about toxicity and true benefits in long-term outcome have hampered its use. Methods: We present the follow-up of younger patients with de novo AML treated on ECOG study E1900, on an intention-to-treat (ITT) and per protocol (PP) analysis. DFS and OS were measured from the time of registration to consolidation therapy. Results: 657 patients younger than 61 years were initially randomized to standard-dose cytarabine and either standard- or high-dose daunorubicin in a 7+3 approach. Of the 352 patients who entered consolidation phase, 307 patients, 68 with favorable-risk cytogenetics (FRC), 128 with intermediate-risk cytogenetics (IRC), 90 with indeterminate cytogenetics (IDT) and 21 with unfavorable-risk cytogenetics (URC), were allocated to AutoHCT. Patients in these cohorts were treated with high-dose cytarabine 3g/m2 x 6 doses in 5 days, for two cycles. Peripheral blood cells were collected after the second cycle. Initially patients were randomized to receive gemtuzumab ozogamicin (GO) or not; however, no benefit was derived from GO therapy and the randomization was closed. 156 patients did not receive the planned AutoHCT due to disease progression, alternative therapy, failure to collect, insurance denial, toxicity and other reasons. 151 patients (33 FRC, 64 IRC, 47 IDT and 7 URC) were conditioned with IV busulfan 0.8 mg/kg daily x 16 doses (without dose adjustment) and cyclophosphamide 60 mg/kg x 2 days. Autologous cells were infused on day 0 and patients were supported with sargramostim until ANC recovery > 500/μL. Veno-occlusive disease occurred in three patients. Treatment-related mortality (TRM) of AutoHCT was 1.3% (2/151) at 30 days. Median follow-up was 31.8 months. In the ITT analysis, median disease-free survival (DFS) was 21.1 months and overall survival (OS) was 31.8 months. For patients treated PP, median DFS and OS were 29.8 months and 39.7 months, respectively. Median DFS by cytogenetics was, 20.5 months for IRC and 22.4 months for IDT; not reached for the FRC group (p=0.10) and median OS was 32.8 months for IRC and 34.4 months for IDT; not reached for the FRC group (p=0.06). For FRC patients treated with high dose daunorubicin induction and AutoHCT the DFS and OS was ≥ 80% at 4 years based on K-M estimates. Patients who were FLT3-positive (n=27) demonstrated a trend towards worse DFS (16.2 vs. 30.3 months) and OS (20.0 vs.39.7 months) than those who were FLT3-negative (n=113) (p=0.12 and 0.10, respectively). Conclusions: Auto HCT is a safe consolidation approach with a low TRM in younger patients with de novo AML in first remission. Results are excellent in respect to DFS and OS particularly for the FRC patients on the high-dose daunorubicin arm. Due to small numbers, we could not demonstrate a negative outcome in FLT3-positive patients receiving AutoHCT. Further study, however, with a larger number of patients is warranted. Disclosures: Fernandez: Otsuka: Honoraria. Off Label Use: IV busulfan in the treatment of acute myeliod leukemia .

Abstract Abstract 2878 Poster Board II-854 Background: Significant advances have been made in the treatment of myeloma with the introduction of thalidomide, its analogue, lenalidomide, and the proteasome inhibitor bortezomib. While these new drugs have improved the outcome of patients with myeloma, the disease still remains incurable. Effectiveness of upcoming new therapies will need to be assessed in the context of anticipated outcome with the currently available therapies. However, given the rapid pace of development over the past decade, outcome of patients who have relapsed on the new therapies remain unclear. Methods: In order to further study this group of patients, we undertook a study of patients who have relapsed on or are refractory to one of the IMiDs (thalidomide or lenalidomide) as well as bortezomib. A total of 300 cases from 8 sites in the US, 5 sites in Europe and one site in Asia were identified for this study. Enrolled patients had relapsed and refractory multiple myeloma, per the EBMT or IMWG response criteria, after at least 2 prior treatments. Patients were refractory to bortezomib, defined as having no response on a prior bortezomib-containing regimen or experiencing disease progression within 60 days of a bortezomib-containing regimen. Patients also should have relapsed, refractory, intolerant, and/or ineligible in the opinion of the investigator, to other therapies, including an IMiD (thalidomide or lenalidomide). Clinical and laboratory data pertaining to the time of diagnosis and from the time of individual relapses were obtained from the clinical records. The date patients satisfied the above entry criteria was defined as time zero. Results: The current analysis includes the first 119 patients with complete data available. The median age at initial diagnosis was 59 years (range, 31-86 yr); 71% were males. The ISS stage distribution at diagnosis was 33%, 39% and 28% for stages 1, 2, and 3 respectively. 19 patients (37%) had high risk disease by FISH [t(4;14), t(14;16), del17p] or by cytogenetics [del 13, hypodiploidy]. The median time from diagnosis to time zero was 3.8 yrs (range 0.2-18.7 yr) and the median reported lines of therapy before time zero was 2. 74% patients had at least 1 autologous stem cell transplant prior to becoming eligible for the study. Following time zero, 77 (65%) pts had a treatment recorded, including an autologous SCT in 21 (18%), with the treatment regimen starting at a median of 1 month after time zero. A variety of treatment regimens were utilized beyond time zero (median=1; range 0-7). Thirty-two (27%) patients had a response any time following time zero, and only 8 had a subsequent response. Response to the first treatment, or supportive care for patients not treated, recorded following time zero included minor response or stable disease (n=14; 12%), PR (n=17, 14%), and VGPR or better (n=6, 5%). Patients treated with SCT had a higher rate of PR or better compared to patients receiving other treatments (85%; 17/20 vs. 26%; 15/57). In a multivariate analysis, the only significant predictor of a PR or better after time zero was younger age (<60 yrs). The median overall survival (OS) and event free survival (EFS) were 6 mos (95% CI, 4-7 mos) and 1 month (95% CI,1-2 mos) respectively. In a multivariate analysis normal creatinine predicted for a better overall survival and having an IgG M protein type predicted for better EFS. A complete analysis from all 300 patients will be presented at the meeting. Conclusions: This study confirms the poor outcome of patients once they become relapsed and refractory to agents that have become the mainstay of myeloma therapy. The findings highlight the incurable nature of the disease and urgent need to develop newer effective therapeutic agents for this group of patients, who currently do not have effective treatment options. Disclosures: Kumar: CELGENE: Research Funding; MILLENNIUM: Research Funding; BAYER: Research Funding; GENZYME: Research Funding; NOVARTIS: Research Funding. Jagannath:Merck: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees. Laubach:Novartis: . Palumbo:Ortho Biotech, Janssen-Cilag: Honoraria; Celgene: Honoraria, Speakers Bureau. Richardson:Millennium Pharmaceuticals, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Johnson and Johnson: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keryx: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. San Miguel:Millennium: Membership on an entity's Board of Directors or advisory committees; Janssen-Cilag: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Siegel:Celgene: Speakers Bureau; Millennium: Speakers Bureau. Sonneveld:Janssen-Cilag: Honoraria. Durie:Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees.

Abstract This study was coordinated by the ECOG-ACRIN Cancer Research Group (Robert L. Comis, MD and Mitchell D. Schnall, MD, PhD, Group Co-Chairs) and supported in part by Public Health Service Grants CA180794, CA180820, CA180795, CA180791, CA189859, CA180790, CA180853, and from the National Cancer Institute, National Institutes of Health and the Department of Health and Human Services. Its content is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute. Background: Relapse after achieving a complete remission (CR) in AML portends for a poor prognosis and allogeneic transplant after achieving a second remission is the only chance for cure. Patients who undergo a transplant have a 30-40% chance of long term survival. This is a follow-up of a report published 10 years ago (Rowe JM, ASH 2005, abstract 546) and includes contemporary studies and longer follow-up. The study examines the long term overall survival (OS) of AML patients who relapsed after achieving first CR in 9 successive ECOG-ACRIN trials for newly-diagnosed AML patients (E3483, E3489, PC486, E3993, E4995, E1490, E3997, E1900 and E3999) from March 1984 to November 2008. Methods: OS was defined as time from first relapse to death from any cause. Kaplan-Meier estimates were used to estimate the event-time distributions for OS. Multivariate model stratified on protocol and treatment were used to examine whether the following factors are prognostic for OS from relapse: age, gender, cytogenetic risk, ECOG performance status, WBC, platelets, hemoglobin, marrow blasts, peripheral blasts, and duration of CR. All P values were based on 2-sided tests. Results: A total of 3160 patients were enrolled in the 9 studies. The median follow-up on patients still alive was 10.0 years. Among those 3160 patients enrolled, 1864 (58.9%) achieved first CR of which 1086 (58.2%) had documented relapse. The median age at diagnosis of the relapsed patients was 50 (range: 16-84) and 50.6% were males. Fifty percent of the patients had reliable cytogenetic results. Of those, 13.5% had favorable cytogenetics, 55.8% - intermediate and 30.6% had unfavorable baseline results. The median OS from relapse was 0.5 years. The 2- and 5-year OS were 16(±1)% and 10(±1)%, respectively. This is true in even the most contemporary studies (E1900 and E3999) with median OS of 0.6 and 0.4 years, respectively. By age stratification (< or ≥ 55), 5-year OS was 13(±1)% and 5(±1)%, respectively (figure 1). Among patients<55, those with unfavorable cytogenetics had the poorest prognosis (median OS of 0.4 years and 5-year OS of 6(±3)%. Those with favorable and intermediate cytogenetics had similar OS with 0.7 and 0.6 years median OS and 5-year OS of 16(±5)% and 17(±3)%, respectively (figure 2). Multivariate analysis was perfomed on 517 patients who had enough baseline information, including cytogenetics. Factors that were significantly associated with OS from relapse included: age (p<0.001), ECOG performance status (p=0.04), hemoglobin (p=0.03), cytogenetics (p=0.045) at baseline and duration of CR (p<0.001). Conclusions: The short- and long-term OS of AML patients post-relapse is dismal (<10%). Although age<55 and favorable cytogenetics at diagnosis are relatively good prognostic factors, the general survival of even these patients is very poor. Disappointingly, these data are also applicable to the most contemporary studies. Long-term survival was possible only in the minority of patients who survived the relapse, achieved a second CR and then successfully underwent an allogeneic transplant. These data are crucial when considering post-remission strategy, and suggest that offering a therapy most likely to lead to cure in CR1 is the preferred option. Figure 1. Probability of OS from relapse by age group Figure 1. Probability of OS from relapse by age group Figure 2. Probability of OS from relapse by cytogenetic risk for patients age <55 Figure 2. Probability of OS from relapse by cytogenetic risk for patients age <55 Disclosures Douer: Gilead: Consultancy. Rowe:BioSight Ltd.: Consultancy, Membership on an entity's Board of Directors or advisory committees; BioLineRx Ltd.: Consultancy; Amgen: Consultancy.

Abstract Lenalidomide is an orally active immunomodulatory drug effective in the treatment of multiple myeloma. We evaluated the toxicity and efficacy of MPR combination in a phase I/II study. Patients with newly diagnosed symptomatic multiple myeloma who were not candidates or refused stem cell transplantation were eligible. Treatment consisted of M and P on days 1 – 4 and R on days 1 – 21 in a 28 day cycle. All patients received aspirin 325 mg a day. Routine antibacterial prophylaxis was not used. Patients were accrued in cohorts of 3 at dose level 0 (M 5mg/m 2/d P 60 mg/m2/d R 10 mg/d) and level 1 (M 8mg/m2/d P 60 mg/m2/d R 10 mg/d). Patients were followed for at least 2 cycles to assess Dose Limiting Toxicity (DLT). G/GM-CSF use was not allowed in the first 2 cycles unless DLT had occurred. DLT was defined as occurrence of at least grade (G) 4 hematologic toxicity, G3 febrile neutropenia, or G 3 non-hematologic toxicity in the first two cycles. Failure to start the next cycle within 7 days of day 1 due to toxicity also constituted DLT. Results: 7 patients have been accrued (4 at dose level 0 {one patient had to be replaced} and 3 at dose level 1). 4 were males. ECOG performance status was 0 or1 (2 and 4 patients). Median age was 74 yrs, range 72 – 85. Between 3 and 10 cycles (median 4) have been administered at the time of this reporting. The following G3 or higher toxicities were encountered and considered at least possibly related to treatment: 2 patients at level 0 had G3 neutropenia. Of the three patients at dose level 1, there was 1 G4 neutropenia, 1 G4 thrombocytopenia, 1 G3 hyperglycemia and 1 G4 vascular access device related thrombosis. Responses were defined by EBMT/IBMTR criteria. 1 had a complete remission (after 3 cycles), 4 had partial remission (at least 50% reduction in monoclonal protein) and 1 had minimal response (after 3 cycles). Due to 3 DLT’s in dose level 1, dose level 0 was chosen for phase II of the study. Conclusion: M 5 mg/m2, P 60 mg/m2 and R 10 mg combination is well tolerated and appears effective in patients with multiple myeloma. These results are similar to the experience reported by Palumbo et al (Blood2005, 106(11):abst 785) although a stricter definition of DLT was used in our study. Escalation of R dose in combination with M 5 mg/m2, P 60 mg/m2 may be possible and improve responses. Updated data will be presented.

Abstract Small lymphocytic lymphoma (SLL) is an incurable indolent lymphoma, and there are relatively few prognostic biomarkers for this important NHL subtype. We evaluated the hypothesis that inherited variability in cytokine and immune-related genes was associated with overall survival in SLL. We genotyped 73 SNPs in 44 candidate genes in 140 SLL patients aged 20–70 years who participated in a population-based case-control study conducted from 1998–2000 through the Surveillance, Epidemiology, and End Results (SEER) cancer registries in Detroit, Seattle, Iowa, and Los Angeles. DNA was extracted from a venous blood sample or mouthwash buccal cell sample. All genotyping was conducted at the National Cancer Institute Core Genotyping Facility using the Taqman platform. Histology, stage, presence of B-symptoms, first course of therapy, date of last follow-up, and vital status were derived from linkage to registry databases at each study site in the spring of 2005. Cox proportional hazards analysis was used to estimate the hazard ratio (HR) and 95% confidence interval for the association between individual SNPs and overall survival, adjusted for age, demographic and clinical factors. Multiple simultaneous modeling strategies were used to identify the best summary multi-SNP risk score to predict survival. At last follow-up, there were 45 deaths in 140 patients (32%). The median follow-up of the 95 surviving patients was 58 months (range 24–75 months). In multivariate modeling, SNPs in IL13 (rs1800925; HRCC=2.36, 1.24–4.49), IL7R (rs1494555; HRGG =2.20, 0.84–5.76), and TNF-alpha (rs1800630; HRAC/AA=1.73, 0.95–3.17) were the strongest and most robust predictors of survival. Two or more deleterious genotypes from these three SNPs increased the risk of death (HR=2.2, 1.2–4.1) compared with one or fewer deleterious genotypes (p=0.009). Three groups (low, intermediate, and high risk) were defined by combining the SNP score and a clinical/demographic score. The 5-year Kaplan-Meier survival estimates for these groups were 85%, 65%, and 11%, respectively. Compared to patients with a low risk score, patients with intermediate (HR=2.5, 1.2–5.1) or high (HR=11, 4.3–27.7) risk scores had poorer overall survival (p=3.9 x 10−8). Our preliminary results suggest that SNPs in IL13, IL7R, and TNF-alpha alone and in combination predict overall survival in SLL, lending support to the hypothesis that host genetic background is a promising class of prognostic biomarkers in SLL.

Abstract The ECOG-ACRIN Cancer Research Group Led Trial, E2902, was a randomized phase III North American Leukemia Intergroup trial of the Farnesyl Transferase Inhibitor , R115777(Tipifarnib), as maintenance therapy for acute myeloid leukemia (AML). Patients (pts) with AML in remission after requiring salvage therapy (primary induction failure or second or subsequent remission) or over the age of 60 in first remission were eligible. Pts were eligible if they were in a complete remission (CR) or complete remission without platelet recovery (CRp) as confirmed by bone marrow examination within 2 weeks prior to randomization. Consolidation or post remission therapy prior to enrollment was allowed but not required. Pts who had received an allogeneic transplant in this remission were ineligible. Adequate blood counts (absolute neutrophil count >= 1000/mm3 and platelet count >=50,000/mm3), and normal renal, and hepatic function were required within 2 weeks of randomization. Pts were randomized to either receive tipifarnib twice daily (BID) or to observation. Pts were stratified by remission ( CR1 vs > CR1) and whether or not they received consolidation therapy in the current remission. The main objective of this study was to compare disease free survival(DFS) in the two groups. Between August 2004 and December 2009, 144 pts were accrued to the study. The median age of the pts was 69 (range 28-86). Seventy-three pts (51%) were male and 135 pts (94%) were white. The majority of pts enrolled on the study (70%) were in first CR, and had post remission chemotherapy (56%) prior to randomization. Seventy-three pts were enrolled onto the treatment arm (Arm A) and 71 pts were enrolled onto the observation arm (Arm B). When the study was initially opened, pts on Arm A were treated with tipifarnib at a dose of 400 mg BID with dose reductions and interruptions defined per protocol for toxicity. After the first planned interim analysis, based on toxicity data, the ECOG Data Monitoring Committee recommended that the starting dose be decreased to 300 mg BID. While non-hematologic toxicity was acceptable, significant hematologic toxicity was seen in pts treated at an initial dose of either 400 mg or 300 mg BID. Of note, hematologic toxicity was also seen on the observation arm although less frequently than with both treatment doses. The primary endpoint of the study was analysis of DFS on an intent to treat basis. The median DFS for arms A and B are 8.87 months and 5.26 months respectively ( p=0.058, HR 0.760). When restricted to eligible patients only(n=134 ), the DFS for arms A and B are 10.81 vs 5.26 months, respectively ( p=0.019, HR 0.690). An unplanned subgroup analysis was performed by gender. The median DFS for male pts (n=73) is 5.36 vs 5.91 months for arms A and B respectively (p=0.868, HR 1.320) and 12.09 vs 3.91 months for female pts (n=71)(p=0.0002, HR=0.408) In a multivariate Cox proportional hazards model to adjust for baseline clinical variables, there is a significant interaction between treatment and gender. (Table 1) Similar results were noted for OS (Figure 1). ECOG ACRIN Trial E2902 evaluated the potential role of Tipifarnib ( R115777) in patients with AML in remission with a high risk of relapse. While the primary endpoint for improved DFS was not reached when evaluating all randomized pts, when restricted to eligible patients only, there is a statistically significant improvement in DFS seen. Moreover, an unplanned subgroup analysis by gender demonstrates an improvement in DFS and OS for females who were enrolled on the study which persists on multivariate analysis. Possible explanations include the use of flat dosing rather than BSA based dosing on this study. However futher evaluation of patient and disease characteristics, dosing and toxicity profiles of responders and nonresponders is needed. Given what appears to be a potentially clinically relevant benefit, further evaluation of this agent is warranted. Table 1. Multivariate Cox Proportional Hazards Model for DFS: All Randomized Patients Hazard Ratio (95% CI) P value Arm B vs A 2.559(1.547,4.236) 0.00025 Male vs Female 2.005(1.228,3.274) 0.00544 CR1 vs >CR1 0.447 (0.305,0.656) 0.00004 Figure 1. (A) DFS (B) OS in Female Patients Figure 1. (A) DFS (B) OS in Female Patients Disclosures Rowe: BioSight Ltd.: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy; BioLineRx Ltd.: Consultancy. Larson:Astellas: Consultancy, Research Funding.

Abstract Background: Induction therapy with daunorubicin (Dauno) & cytarabine (Ara-C) [DA] has been the standard of care for eligible older adults (age ≥ 60 years) with newly diagnosed acute myeloid leukemia (AML) for over 2 decades. Single agent Clofarabine (CLO) induction & consolidation (Consol.) therapy has demonstrated important clinical activity in this age group in large phase II studies. Lower induction mortality (IM) & similar reported complete remission rate (CR) & overall survival (OS), as well as notable activity in those with higher risk disease features [including unfavorable cytogenetics, therapy-related AML (t-AML) & prior antecedent hematologic disorder (AHD)] raises the possibility that a non-Ara-C-based regimen could achieve similar or superior OS with lower toxicity. Methods: We performed a randomized United States Intergroup Phase III trial of single agent CLO [30mg/m2 x 5 days induction; 20 mg/m2 re-induction (if indicated) & 2 cycles Consol.] vs. standard DA therapy [Dauno 60mg/m2 D1-3 & Ara-C 100mg/m2 D1-7 induction x 1-2 cycles; 2 cycles Consol. with Ara-C (1.5g/m2 Q12hrs D1-6 age 60-69; once daily if age 70+)] in patients (pts) age ≥ 60 yrs with newly diagnosed AML. Patients with serum creatinine >1.0 (or GFR <60 mL/min) and those with AML-M3 and ECOG performance status >3 (PS>2 if age 70+ yrs) were excluded. Randomization was stratified by age (60-69 vs. 70+), t-AML, & AHD. Pts with HLA-matched donor were eligible for allogeneic transplantation (AlloHCT) after induction, and those completing Consol. were eligible for randomization #2 (R#2) to maintenance decitabine [20mg/m2 x 3D, monthly x 1 year] versus observation. With a target accrual of 747, E2906 was powered to determine non-inferiority [and possible superiority] of CLO vs. standard DA, and primary endpoint was OS. A weighted statistical analysis was performed to account for confounding impact of R#2. AlloHCT patients were censored at transplant in this analysis. Responses & cytogenetics were confirmed centrally and OS & CR rates were monitored by an independent Data Safety Monitoring Committee (DSMC) at pre-specified time points. Results: As of Feb 23, 2015, 727 pts were randomized. Median age was 68 years (range 60-86); 57% were male, and 38% were age ≥70 yrs. Treatment arms are well balanced for all baselineclinical & AML characteristics, & 30% had unfavorable cytogenetics. Of 659 with complete treatment information reported, 30.4% on DA vs. 40.1% on CLO received 2 cycles of induction (p=0.006). Median follow-up of surviving patients is 7.6 months. Table 1. shows early treatment results (CR, toxicity) for the 686 pts randomized as of Dec 23, 2014 (2 months prior to study end, & excluding 90 with ongoing response evaluation). DA CLO p-value CR/CRi 43.8% 42.8% p=0.87 30-day mortality 8.5% 7.9% p=0.89 60-day mortality 14.9% 13.1% p=0.58 Gr 4-5 Non-Heme Tox.Induction 27% 19% p=0.02 Gr 4-5 Non-Heme Tox.Consol. 20% 7% p=0.001 374 pts have died (174, DA; 200, CLO) & significantly inferior OS was observed for CLO vs. DA [Hazard Ratio (HR) 1.41 (95% CI 1.12-1.78)] (Fig. 1). Planned subgroup analyses were performed (Table 2) demonstrating significant differences in OS after CLO for patients age 60-69 yrs, without AHD, & with intermediate risk cytogenetics; but not for those with Unfav. Cytogen. (Fig. 2) or t-AML. Based on the primary weighted analysis, DSMC recommended suspension of new accrual to E2906 on Feb 23, 2015 & all active patients on CLO were transitioned to DA Arm. Table 2.NHR CLO/Standard (95% CI)*Weighted OS7271.41 (1.12-1.78)Unweighted OS7271.23 (1.00-1.50)Age 60-694491.48 (1.10-1.99)Age 70+2781.34 (0.93-1.93)Intermed. Risk Cytogen.3781.77 (1.27-2.47)Unfav. Risk Cytogen.2160.96 (0.65-1.43)No AHD6041.46 (1.13-1.89)AHD1231.22 (0.74-2.00)De novo AML6271.52 (1.18-1.96)Therapy-related AML1000.94 (0.54-1.61) Conclusions: Despite similar CR & IM, OS after single agent CLO is inferior to standard DA therapy for pts age ≥60 years with newly diagnosed AML who are fit for intensive therapy, and DA remains the standard of care. However no difference in OS was observed after CLO in some pre-specified high risk AML subgroups. R#2 & AlloHCT arms continue in E2906 for pts already enrolled. Embedded prospective minimal residual disease study at CR is being performed to identify pts at higher risk after CLO & DA. Figure 1. Weighted Kaplan-Meier Curves for OS Figure 1. Weighted Kaplan-Meier Curves for OS Figure 2. Unfavorable Cytogenetics OS by Therapy Figure 2. Unfavorable Cytogenetics OS by Therapy Disclosures Off Label Use: Use of clofarabine in AML, and maintenance therapy with decitabine in AML. Claxton:Medimmune: Research Funding; BMS: Consultancy; Astellas: Research Funding; Cyclacel: Research Funding; Merck: Research Funding; Ambit: Research Funding. Levine:Loxo Oncology: Membership on an entity's Board of Directors or advisory committees; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees; Foundation Medicine: Consultancy. Altman:Seattle Genetics: Consultancy; BMS: Consultancy; Spectrum: Consultancy; Astellas: Consultancy; Ariad: Consultancy; Novartis: Consultancy. Al-Kali:Novartis: Research Funding.

Abstract Introduction Polycythemia vera (PV) is characterized by excessive production of erythroid cells and in most cases a point mutation (V617F) in the Jak2 cytokine signaling kinase. We investigated whether a selective JAK2 inhibitor decreased Jak2 V617F induced erythroid differentiation. Methods Wild-type and mutant Jak2 V617F genes were excised from the retroviral Jak2-mus-MSCV-neo vector (Levine et al), cloned into the lentiviral vector pLV CMV IRES2 GFP and their presence verified by DNA sequencing. Lentiviral vectors bearing the wild-type and mutant Jak2 genes or vector alone were used to transduce human peripheral blood CD34+ cells, which were then divided for plating into megacult medium for megakaryocytic colony growth and methylcellulose culture for enumeration of all other progenitor cell types. Normal cord blood HSC (CD34+/CD38−/CD90+) were clone sorted with the FACS Aria and transduced with no vector, backbone vector, wild-type JAK2 or mutant JAK2 vector in methocult media (Stem Cell Technologies Inc, GF+ H4435) +/− 300 nM of a selective JAK2 inhibitor, TG101348. Colonies were scored at day 14. RNA was isolated from the colonies (Qiagen RNeasy kit) and RT-PCR was performed with wild-type and mutant JAK2 allele specific primers. Results Transduction of cord blood HSC with the mutant Jak2 vector resulted in skewed erythroid colony formation compared to wild-type Jak2, vector alone and untransduced HSC (Figure 1; n=3). RT-PCR with murine Jak2 specific primers resulted in ~900 bp fragments corresponding to murine Jak2 from colonies transduced with the wild-type and mutant Jak2 and confirmed by sequencing, but not those from colonies transduced with the vector alone or the untransduced cells. Like the results in cord blood cells, adult peripheral blood CD34+ cells transduced with the mutant Jak2 developed a skewed developmental pattern, with far greater erythroid colony formation compared to wild-type Jak2 or vector alone. In megacult assays, CD34+ cells transduced with the mutant Jak2 had similar megakaryocytic potential as wild-type Jak2 or vector alone. Addition of TG101348 (300 nM), inhibited mutant kinase-induced erythroid colony formation (Figure 1) in 3 experiments while 100– 300 nM was inhibitory to PV (n=2 patients) HSC and progenitors. Current experiments focus on inhibition of Jak2 in a bioluminescent highly immunocompromised mouse model of Jak2V617F-induced myeloproliferation (Figure 2). Conclusion JAK2 V617F skews differentiation of HSC toward the erythroid lineage and may be inhibited with a selective JAK2 inhibitor - TG101348. Figure 1. In vitro JAK2 Inhibition. Figure 1. In vitro JAK2 Inhibition. Figure 2. Bioluminescent JAK2 V617F-induced Myeloproliferation Model. Figure 2. Bioluminescent JAK2 V617F-induced Myeloproliferation Model.

Abstract Acute Lymphoblastic Leukemia (ALL) is the most common malignancy observed in the pediatric population. Recent genomic studies have made considerable strides in improving our understanding of the molecular pathogenesis of pediatric B-cell ALL. This includes the discovery of recurrent somatic alterations targeting B-cell transcription factors, mutations in epigenetic regulators, and oncogenic mutations which activate signaling effectors, including in Ph-like B-ALL. However, the molecular pathogenesis of adult B-cell ALL has been less well studied, and there is a need to identify novel therapeutic targets in adult B-ALL. We therefore performed detailed genomic profiling in adults with B-cell ALL. We performed targeted DNA/RNA capture and sequencing of 189 patients with B-cell ALL enrolled on the ECOG E2993 clinical trial. All samples were taken at the time of diagnosis before patients were treated with multi-agent chemotherapy and followed for clinical outcomes including overall survival and remission/relapse duration and kinetics. We used the FoundationOne® Heme assay for our genomics study. This platform allows us to identify short events (point substitutions, short insertions/deletions) copy number and fusion events present in DNA and/or RNA. Of the 203 samples profiled, 189 had sufficient quality genomic data with a median coverage of 435 on DNA sequencing and 7.85 million on target distinct reads per case on RNA sequencing. In all, we identified cancer-related mutations in 108 genes, 55 of these genes being mutated in more than one sample. We identified a median of 2.98 genomic alterations per sample (standard deviation of 1.78) in the target gene set, which included all genes known to be altered in B-ALL and in other hematologic malignancies. The most common genomic events were the BCR-ABL1 fusion (69 samples, 36.5%), followed by CDKN2A loss (57 samples, 30%), CDKN2B loss (35 samples, 18%), NRAS and KRAS point mutations (32 samples, 16.9%), and MLL fusion genes with a spectrum of partners (25 samples, 13.2%). Notably, we found that BCR-ABL1 fusion are mutually exclusive with both RAS mutations (p<10^-7) and MLL mutations (p<5*10^-4). We next investigated the spectrum and frequency of alterations observed in different classes of oncogenes/tumor suppressors. We identified mutations which result in activation of oncogenic signaling pathways in 130 cases or 68.7% of our cohort. This included known mutations/fusions, such as BCR-ABL, RAS-MAPK pathway mutations, and JAK-STAT pathway alterations, and included missense alleles, insertion/deletion events, and fusion genes targeting a spectrum of genes including ABL, PDGFRB, and CRLF2. In aggregate, 33.8% of the cohort had mutations which activate signaling exclusive of BCR-ABL, demonstrating the high prevalence of the Ph-like B-ALL subtype in adult B-ALL. We identified mutations affecting key transcription factors, including PAX5 and IKZF1, in 31.2% of our cohort including missense, nonsense and deletion events. To confirm our ability to detect small deletions of PAX5 and IKZF1, we performed array CGH of 50 cases and compared copy number calls using high-throughput sequencing and CGH. Of note, all deletions targeting PAX5 and IKZF1 identified by NGS were confirmed by CGH. We also identified mutations in epigenetic regulators in 30.6% of cases, including MLL fusions, mutations in the DNA methylation/hydroxymethylation the pathway (DNMT3A, TET1, TET2), and mutations targeted chromatin modulators. Detailed analyses of the mutational spectra and their relationship to clinical outcome will be presented at the meeting. Taken together, these data show we can use a clinically validated sequencing assay to identify known and novel somatic mutations in adult B-ALL, including sequence alterations, rearrangements and copy number aberrations. These data demonstrate the feasibility of combined DNA and RNA study to identify a complex landscape of fusions and short mutations with prognostic and therapeutic relevance, and inform the use of genomic profiling in B-ALL in the clinical context. Figure 1. Figure 1. Disclosures He: Foundation Medicine, Inc.: Employment, Equity Ownership. Brennan:Foundation Medicine, Inc.: Employment, Equity Ownership. Nahas:Foundation Medicine, Inc.: Employment, Equity Ownership. Balassubramanian:Foundation Medicine, Inc.: Employment, Equity Ownership. Otto:Foundation Medicine, Inc.: Employment, Equity Ownership. Lipson:Foundation Medicine, Inc.: Employment, Equity Ownership. Stephens:Foundation Medicine, Inc.: Employment, Equity Ownership. Miller:Foundation Medicine, Inc.: Employment, Equity Ownership. van den Brink:Boehringer Ingelheim: Consultancy, Other: Advisory board attendee; Merck: Honoraria; Regeneron: Honoraria; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Tobira Therapeutics: Other: Advisory board attendee. Rowe:Amgen: Consultancy; BioSight Ltd.: Consultancy, Membership on an entity's Board of Directors or advisory committees; BioLineRx Ltd.: Consultancy. Levine:Foundation Medicine: Consultancy; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees; Loxo Oncology: Membership on an entity's Board of Directors or advisory committees.