Citations

Abstract Introduction: Waldenström's macroglobulinemia (WM) is a rare, indolent B-cell lymphoma characterized by lymphoplasmacytic cell infiltration of bone marrow and elevated serum levels of immunoglobulin M (IgM) protein. Despite recent advances in treatment the disease relapses in most patients. About 90% of WM patients harbor the MYD88 L265P oncogenic mutation. MYD88 is an adapter protein in the Toll-like receptor (TLR) pathway. The MYD88 L265P oncoprotein has been shown to amplify TLR 7 and 9 signaling, leading to downstream activation of NF-κB and cytokine signaling pathways that promote tumor cell survival and proliferation (Lim, AACR 2013). IMO-8400 is an investigational oligonucleotide antagonist of endosomal TLRs 7, 8 and 9. In preclinical studies in a human cell line and animal models of WM, IMO-8400 inhibited key cell signaling pathways, including NF-κB, BTK, STAT-3 and IRAK-4, and inhibited tumor growth and tumor IgM production. In Phase 1 and 2 clinical trials in healthy subjects (N=30) and in patients with autoimmune disease (N=35), IMO-8400 was generally well tolerated and demonstrated evidence of clinical activity. Based on these data, we initiated a Phase 1/2 clinical trial of IMO-8400 in WM, the first study of a drug candidate specifically targeting the MYD88 L265P mutation. Methods: This Phase 1/2 multicenter, open-label, dose-escalation clinical trial continues to recruit adult patients with relapsed or refractory WM (NCT Identifier: NCT02092909). In a classic 3x3 dose escalation scheme, patients are enrolled in one of three sequential escalating dose cohorts and receive subcutaneous IMO-8400 at dosages of 0.6, 1.2 or 2.4 mg/kg per week, respectively, for 24 weeks. The presence of the MYD88 L265P mutation is assessed by PCR-based genetic screening following enrollment. Patients who complete the 24-week treatment period are eligible to enroll in an extension trial. The primary study objective is to evaluate the safety and tolerability of escalating IMO-8400 dosages. Secondary objectives include preliminary evaluation of clinical response based on international guidelines and identification of an optimal dose for further evaluation (Kimby, Clin Lymphoma Myeloma 2006). Results: Overall, 17 patients (6 female, 11 male) have been enrolled in three dose cohorts to date. Median baseline characteristics include: age 66 years, prior therapies 4 (range 1-13), serum IgM 2,225 mg/dL, serum M protein 0.96 g/dL, and B2-microglobulin 3.42 mg/L. IMO-8400 has been generally well tolerated across all dose cohorts to date, with patient exposure ranging from 2-46 weeks in the Phase 1/2 and extension trials. The most common adverse events reported to date include transient flu-like symptoms and injection site reactions. One serious adverse event of worsening grade 3 arthritis, deemed possibly related to study drug, was reported in a patient with a pre-existing history of arthritis in the 2.4 mg/kg dose cohort. This patient discontinued study treatment. To date, no other patients have discontinued treatment due to treatment-related adverse events. Preliminary evidence of clinical activity for IMO-8400 has been observed in all dose cohorts. In June 2015, an independent Data Review Committee reviewed 4-week safety data from the highest dose cohort and agreed that 2.4 mg/kg was safe for further evaluation. Safety, pharmacokinetics and preliminary activity for all three dose cohorts will be presented. Conclusions: IMO-8400 is a mutation-targeted therapy in development for the treatment of patients with relapsed or refractory WM. In an ongoing Phase 1/2 clinical trial in WM, IMO-8400 has been generally well tolerated and has demonstrated preliminary evidence of clinical activity. Safety results support continued evaluation of IMO-8400 at 2.4 mg/kg/week in this patient population. Disclosures Thomas: Novartis, Celgene, Acerta Pharmaceuticals, Idera Pharmaceuticals: Research Funding. Harb:Astex Pharmaceuticals, Inc.: Research Funding; Idera Pharmaceuticals: Research Funding. Beck:Idera Pharmaceuticals: Research Funding. Nashat:Idera Pharmaceuticals: Research Funding. Ansell:Idera Pharmaceuticals: Research Funding. Eradat:Idera Pharmaceuticals: Research Funding. Libby:Idera Pharmaceuticals: Research Funding. Hajdenberg:Celgene: Speakers Bureau; Novartis: Speakers Bureau; Incyte: Speakers Bureau; AbbVie: Speakers Bureau; Gilead: Speakers Bureau; Janssen: Speakers Bureau; Idera Pharmaceuticals: Research Funding. Heffner:Idera Pharmaceuticals: Research Funding. Hoffman:Idera Pharmaceuticals: Research Funding. Vesole:Celgene Corporation: Speakers Bureau; Idera Pharmaceuticals: Research Funding. Simov:Idera Pharmaceuticals: Employment. Wyant:Idera Pharmaceuticals: Employment. Brevard:Idera Pharmaceuticals: Employment. O'Leary:Idera Pharmaceuticals: Employment. Agrawal:Idera Pharmaceuticals: Employment.

Abstract Introduction Ibrutinib has become a new standard of care in patients with previously treated CLL/SLL based on the phase 3 RESONATE study (Byrd, et al. NEJM 2014) and other trials evaluating ibrutinib mainly as a single agent in CLL. The first randomized, double-blind, placebo-controlled phase 3 study (HELIOS) investigating ibrutinib in combination with bendamustine and rituximab (BR) was recently reported (Chanan-Khan, et al. ASCO 2015), with ibrutinib significantly extending progression-free survival and reducing the risk of progression/death by 80%. The study design provides an opportunity to examine the overall safety and management of adverse events (AEs) with ibrutinib and placebo in a blinded manner that previously has not been possible. Here we examine the safety and management of AEs with ibrutinib + BR vs placebo + BR in HELIOS. Methods Patients with active CLL/SLL following ≥ 1 prior line of systemic therapy were randomized 1:1 to receive BR (≤ 6 cycles) with either ibrutinib 420 mg daily or placebo (n = 289 in each group). Safety was a secondary end point. Results Median exposure to ibrutinib and placebo was 14.7 and 12.8 months, respectively. Rates of infection in the ibrutinib + BR and placebo + BR arms were similar (all-grade, 70.4%; grade ≥ 3, 26.8% vs all-grade, 70.0%; grade ≥ 3, 22.6%, respectively) but exposure-adjusted analysis reveals an overall lower rate of infections with ibrutinib + BR vs placebo + BR (10.3/100 vs 11.2/100 patient-months), with similar rates of grade ≥ 3 infections (2.4/100 patient-months each arm). Rates of all-grade (grade 3/4) anemia were 22.3% (3.5%) with ibrutinib + BR and 28.9% (8.0%) with placebo + BR. Patients also required fewer transfusions with ibrutinib + BR (23%) vs placebo + BR (29%), the majority of which were red blood cell transfusions. Similar proportions of patients used growth factors in both arms (54% vs 52%, respectively). Grade 3/4 neutropenia was reported at similar rates in both arms (53.7% vs 50.5%, respectively); however, fewer patients discontinued due to treatment-related neutropenia with ibrutinib + BR (1.0%) vs placebo + BR (2.8%). Rates of thrombocytopenia were slightly higher with ibrutinib + BR (30.7%) than placebo + BR (24.0%), but rates of grade 3/4 events were similar between arms (15.0% each arm). Atrial fibrillation (AF) was observed more frequently in patients on ibrutinib + BR than placebo + BR (7.3% vs 2.8% overall and 2.8% vs 0.7% grade 3/4, respectively). However, only 4 patients with grade 3/4 AF discontinued therapy in the ibrutinib arm. No patients with grade 1/2 AF discontinued treatment. One-third of patients held ibrutinib treatment to manage AF, with all restarting at the same dose (420 mg). Median (range) time to onset was 3.0 (0.3-17.5) months with ibrutinib + BR and 2.4 (0.6-18.9) months with placebo + BR. Importantly, in those with a prior history of AF or abnormal heart rhythm, only 7/25 receiving ibrutinib + BR and 2/22 receiving placebo + BR developed AF/atrial flutter on study. The rates of any-grade bleeding were 31.0% and 14.6%, respectively, with the majority being grade 1 (77.5% and 69.0%, respectively). Low rates of grade 3/4 major bleeding were observed in the ibrutinib + BR (2.1%) and placebo + BR (1.7%) arms. Many patients (41.8% ibrutinib + BR, 41.1% placebo + BR) were receiving concomitant anticoagulant/antiplatelet medication. A low rate of treatment-related lymphocytosis was observed in both arms (7.0% ibrutinib + BR, 5.9% placebo + BR). The majority of cases resolved within 2 weeks. Conclusions In this randomized, double-blind, placebo-controlled trial, the addition of ibrutinib to BR was well tolerated and did not significantly impact the safety profile of BR. In addition, ibrutinib was associated with reduced rates of anemia and transfusional support. Consistent with its known toxicity profile, patients in the ibrutinib + BR arm had higher rates of bleeding (mostly grade 1 or 2) and AF; however, few patients discontinued therapy as a result of these AEs. A prior history of AF or abnormal heart rhythm did not lead to recurrent episodes in the majority of cases. Taken together, the results from HELIOS establish the significant efficacy of ibrutinib and also the overall positive risk-benefit profile of ibrutinib + BR. Disclosures Cramer: Janssen: Other: Travel grant, Research Funding, Speakers Bureau; Hoffman LaRoche: Other: Travel grant, Research Funding, Speakers Bureau; Astellas: Other: Travel grant; Glaxo Smith Klein/Novartis: Research Funding; Gilead: Other: Travel grant, Research Funding; Mundipharma: Other: Travel grant. Demirkan:Celgene: Other: Travel reimbursement; Amgen: Consultancy. Fraser:Hoffman LaRoche: Consultancy, Honoraria; Janssen: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding. Santucci Silva:Janssen: Other: Travel reimbursement, Research Funding; GSK: Research Funding; Celgene: Research Funding; Merck: Research Funding; Novartis: Other: Travel reimbursement; Hoffman LaRoche: Other: Travel reimbursement, Research Funding. Janssens:Roche: Consultancy, Speakers Bureau; Mundipharma: Speakers Bureau; Janssen: Consultancy. Goy:Allos, Biogen Idec, Celgene, Genentech, and Millennium. Gilead: Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Mayer:Janssen: Research Funding. Dilhuydy:Roche: Honoraria, Other: Travel reimbursement; Janssen: Honoraria, Other: Travel reimbursement; Mundipharma: Honoraria. Bartlett:Medimmune: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Genentech: Research Funding; ImaginAB: Research Funding; Astra Zeneca: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; Gilead: Consultancy; Seattle Genetics: Consultancy, Research Funding; Millenium: Research Funding; Celgene: Research Funding. Rule:Roche: Consultancy, Other: Travel reimbursement; Gilead: Research Funding; Celgene: Consultancy, Other: Travel reimbursement; J&J: Consultancy, Other: Travel reimbursement, Research Funding. Sun:Janssen/J&J: Employment, Equity Ownership. Phelps:Janssen/J&J: Employment, Equity Ownership. Mahler:Janssen: Employment, Other: Travel reimbursement. Salman:Janssen/J&J: Employment, Equity Ownership. Howes:Janssen/J&J: Employment, Equity Ownership. Hallek:AbbVie: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Roche: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Gilead: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Pharmacyclics: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Celgene: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Boehringher Ingelheim: Honoraria, Other: Speakers Bureau and/or Advisory Boards; Mundipharma: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Janssen: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding.

Abstract Introduction Recent results from the HELIOS phase 3 study in relapsed/refractory CLL/SLL demonstrated that the addition of ibrutinib to chemoimmunotherapy with bendamustine/rituximab (BR) leads to an 80% reduction in risk of progression or death compared with placebo + BR (Chanan-Khan et al. ASCO 2015). In addition to prolongation of progression-free survival (PFS; median not reached vs 13.3 months; hazard ratio: 0.203, 95% confidence interval: 0.150-0.276, p<0.0001), overall response rate (ORR) and rates of complete response (CR) or CR with incomplete marrow recovery (CRi) were significantly improved with ibrutinib + BR (ORR: 82.7% vs 67.8%; CR/CRi: 10.4% vs 2.8%). Here we report additional analyses on the quality of response with ibrutinib combined with BR. Methods In total, 578 patients (pts) with relapsed/refractory CLL/SLL requiring treatment were randomized 1:1 (289 per arm) to receive BR (≤ 6 cycles) with either ibrutinib (420 mg daily) or placebo. Purine analog refractoriness (yes vs no) and number of prior therapies (1 vs > 1) were stratification factors. Pts with deletion 17p (del17p; > 20% of cells) were excluded. All pts were required to have ≥ 1 abnormal lymph node (LN; defined as a measurable lesion > 1.5 cm). The primary end point was independent review committee (IRC)-assessed PFS. In this analysis, individual parameters of response (LN, spleen, overall radiology, absolute lymphocyte count [ALC], complete blood count [CBC], and bone marrow [BM]) were evaluated. Minimal residual disease (MRD) was assessed by flow cytometry using an 8-color panel (Rawstron AC, et al. Leukemia. 2007;21:956-964); MRD samples were collected at confirmation of suspected CR (bone marrow) and every 3 months thereafter (peripheral blood). Rate of MRD-negative response was defined as the proportion of pts who reached negative disease status (< 0.01%, ie, < 1 CLL cell/10,000 leukocytes) in any sample. Reported MRD rates are based on the intent-to-treat (ITT) population. Results The ORR assessed by the IRC was 82.7% with ibrutinib + BR vs 67.8% with placebo + BR (p < 0.0001), and was consistent with ORR reported by the treating physician (investigator assessed) (ORR: 86.2% vs 68.9%, p < 0.0001). However, rates of CR/CRi were higher by investigator assessment (21.4%, ibrutinib + BR vs 5.9%, placebo + BR) than IRC (10.4% vs 2.8%). The IRC employed an independent evaluation of radiological scans including stringent evaluation of LN and volumetric assessment of spleen size-the main reasons for the difference in CR/CRi rates between investigator and IRC assessment. At baseline, similar proportions of pts in each arm had bulky disease defined as LN > 5 cm (54%-58%) or abnormal spleen (~40%) as assessed by IRC. Complete resolution of previous CLL/SLL manifestations as assessed by the IRC was achieved more often in the ibrutinib + BR arm in comparison with placebo + BR for LN (34.6% vs 15.2%), spleen (56.7% vs 37.0%), overall radiology (21.1% vs 9.0%), and BM (19.7% vs 5.9%). Rates of normalization of ALC (> 90%) and CBC (> 70%) were high and similar in the 2 arms. MRD was assessed in 120 pts treated with ibrutinib + BR and 57 pts treated with placebo + BR and was negative in 37 pts and 14 pts, respectively, which corresponds with an MRD-negative response rate of 12.8% vs 4.8% for ibrutinib + BR vs placebo + BR (p = 0.0011). Investigator-determined responses by different levels of MRD are shown in Table 1. The percentage of pts with an MRD level < 1% was higher with ibrutinib + BR vs placebo + BR (32.2% vs 11.8%). Moreover, the percentage of pts with an MRD level < 0.1% was higher for ibrutinib + BR vs placebo + BR (24.6% vs 7.6%) suggesting that the depth of response with ibrutinib + BR was superior. Kaplan-Meier plots by MRD level (Figure 1) show that a lower MRD level was associated with a longer PFS. However, pts in the ibrutinib + BR arm had a more sustained response at every MRD level compared with pts in the placebo + BR arm. Conclusions Pts treated with ibrutinib + BR showed not only a higher ORR, but also a greater depth of response, with more CRs and a higher rate of resolution of LN, spleen, and BM involvement. Furthermore, the rate and depth of MRD negativity was improved, and appeared to last longer in pts treated with ibrutinib + BR compared with pts receiving placebo + BR. With a median follow up of 17 months in the ibrutinib + BR arm, no MRD-negative pts and few MRD-positive pts had progressed, thus evaluating a trend in PFS with MRD negativity is currently limited in this arm. Disclosures Cramer: Gilead: Other: Travel grant, Research Funding; Glaxo Smith Klein/Novartis: Research Funding; Astellas: Other: Travel grant; Mundipharma: Other: Travel grant; Janssen: Other: Travel grant, Research Funding, Speakers Bureau; Hoffman LaRoche: Other: Travel grant, Research Funding, Speakers Bureau. Off Label Use: Combination of bendamustine, obinutuzumab and ibrutinib for treatment of CLL. Fraser:Hoffman LaRoche: Consultancy, Honoraria; Janssen: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding. Demirkan:Amgen: Consultancy; Celgene: Other: Travel reimbursement. Santucci Silva:Merck: Research Funding; Celgene: Research Funding; GSK: Research Funding; Janssen: Other: Travel reimbursement, Research Funding; Hoffman LaRoche: Other: Travel reimbursement, Research Funding; Novartis: Other: Travel reimbursement. Janssens:Mundipharma: Speakers Bureau; Roche: Consultancy, Speakers Bureau; Janssen: Consultancy. Goy:Allos, Biogen Idec, Celgene, Genentech, and Millennium. Gilead: Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau. Mayer:Janssen: Research Funding. Dilhuydy:Roche: Honoraria, Other: Travel reimbursement; Janssen: Honoraria, Other: Travel reimbursement; Mundipharma: Honoraria. Bartlett:Millenium: Research Funding; Medimmune: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Genentech: Research Funding; ImaginAB: Research Funding; Astra Zeneca: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; Gilead: Consultancy; Seattle Genetics: Consultancy, Research Funding; Celgene: Research Funding. Rule:Roche: Consultancy, Other: Travel reimbursement; J&J: Consultancy, Other: Travel reimbursement, Research Funding; Celgene: Consultancy, Other: Travel reimbursement; Gilead: Research Funding. Sun:Janssen/J&J: Employment, Equity Ownership. Phelps:Janssen/J&J: Employment, Equity Ownership. Mahler:Janssen: Employment, Other: Travel reimbursement. Salman:Janssen/J&J: Employment, Equity Ownership. Schaffer:Janssen: Employment. Balasubramanian:Pharmacyclics LLC, an AbbVie Company: Equity Ownership; Janssen: Employment, Equity Ownership. Howes:Janssen/J&J: Employment, Equity Ownership. Hallek:AbbVie: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Celgene: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Pharmacyclics: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Gilead: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Boehringher Ingelheim: Honoraria, Other: Speakers Bureau and/or Advisory Boards; Roche: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Mundipharma: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding; Janssen: Honoraria, Other: Speakers Bureau and/or Advisory Boards, Research Funding.

Abstract Abstract 2721 Poster Board II-697 The role of the CD40 pathway in B-cell cancers is rather enigmatic due to having polar opposite roles in tumor biology. Stimulation of the CD40 receptor can reduce cell viability of NHL cell lines and xenograft tumor models, whereas, in sharp contrast, constitutive CD40 stimulation can actually promote proliferation of NHL cell lines, as well as drive lymphomagenesis and transformation of primary B-cells. Therefore, targeting the CD40 pathway has been challenging due to a knowledge gap in understanding the factors that may dictate a pro- or anti-tumor role. To address this directly, we employed a large panel of NHL cell lines and xenografts models to simulate a patient population and to define the molecular parameters to test in the context of clinical trials. Using baseline gene expression profiling, we found that the in vitro activity of an antibody that stimulates the CD40 pathway, Dacetuzumab (SGN-40), correlated strikingly with a transcriptional profile that was representative of an inactive CD40 pathway. Resistant cells, on the other hand, displayed a transcriptional profile indicative of an activated CD40 pathway. Consistent with these observations, constitutive phosphorylation of ERK, a node downstream of CD40 signaling, was present predominantly in cell lines that were resistant to Dacetuzumab. Fifteen genes, based on their association with in vitro activity and their biology as components of the CD40 network, were selected as a classifier from these pre-clinical data and independently tested in a panel of cell lines and xenografts models. Testing the selected gene classifier by qRT-PCR from baseline fixed tumor tissue of 39 patients treated with Dacetuzumab in phase I and II clinical trials revealed the ability to predict sensitivity in patients, as determined by tumor shrinkage >10%, with an overall accuracy of 80%. Consistent with the observed tumor shrinkage, the classifier positive, predicted to respond to Dacetuzumab, patients also exhibited a prolonged progression free survival (PFS) compared to classifier negative patients, predicted not to respond to Dacetuzumab (HR = 0.23, p = 0.001). Finally, using a novel microarray approach to genome-wide expression profiling on fixed tumor tissue revealed that CD40 pathway activation was indeed an important predictor of response. Overall, these data suggest that sensitivity to Dacetuzumab can be predicted by pre-determining the CD40 pathway activation status of tumors. Disclosures: Dornan: Genentech, Inc.: Employment, Equity Ownership. Burington:Genentech, Inc.: Employment, Equity Ownership. Yue:Genentech, Inc.: Employment, Equity Ownership. Shi:Genentech, Inc.: Employment, Equity Ownership. Advani:Seattle Genetics, Inc.: Research Funding. Yu:Genentech, Inc.: Employment, Equity Ownership. Lau:Genentech, Inc.: Employment, Equity Ownership. Yu:Genentech, Inc.: Employment, Equity Ownership. De Vos:Seattle Genetics, Inc.: Research Funding. Forero-Torres:Seattle Genetics, Inc.: Research Funding. Modrusan:Genentech, Inc.: Employment, Equity Ownership. Koeppen:Genentech, Inc.: Employment, Equity Ownership. Yang:Genentech, Inc.: Employment, Equity Ownership. Du:Genentech, Inc.: Employment, Equity Ownership. Elkins:Genentech, Inc.: Employment, Equity Ownership. Polson:Genentech, Inc.: Employment, Equity Ownership. Offringa:Genentech, Inc.: Employment, Equity Ownership. Whiting:Seattle Genetics, Inc.: Employment, Equity Ownership. Ebens:Genentech, Inc.: Employment, Equity Ownership.

Abstract Abstract 3063 Background: The combination of Cyclophosphamide, Bortezomib, and Dexamethasone (CYBOR-D) is proven to be highly active and effective in multiple myeloma. (Reeder, Leukemia 2009) We aim to evaluate the safety and efficacy of this regimen in a separate plasma cell neoplasm, AL Amyloidosis. The primary endpoint of this study is hematologic response. Complete hematologic response is defined as normalization of the free light chain ratio with no evidence of a monoclonal protein by immunofixation. Partial hematologic response is defined as a 50% reduction in M-spike or absolute light chain level (Gertz Am J Heme 2006). Methods: We report a series of patients with symptomatic AL Amyloidosis who received treatment with a combination of Bortezomib (1.3mg/m2 on days 1, 4, 8, and 11 every 28 days or 1.5 mg/m2 weekly), Cyclophosphamide (300 mg/m2 orally weekly) and Dexamethasone (40 mg weekly). We include patients in this study regardless of autologous bone marrow transplant candidacy or previous treatment history. Results: Fifteen patients with AL amyloidosis received two to six cycles of CYBOR-D. The treatment history, bone marrow transplant candidacy prior to treatment, hematological response, and status of transplant after therapy are shown in table 1. Of note, 8 (53%) had symptomatic cardiac involvement all of whom had elevated levels of both cardiac biomarkers (Troponin T and B-natriuretic peptide). Complete hematological response occurred in 11 patients (73.3%) with partial hematological response in 3 patients (20.0%). One patient (6.6%) did not achieve a partial response but did receive autologous bone marrow transplant after treatment with CYBOR-D. Median time to response was 2 months. Six patients (40%) had objective evidence of kidney response to therapy with a greater than 50% decrease in proteinuria. Conclusions: CYBOR-D produces a rapid and complete hematological response in the majority of patients with AL amyloidosis regardless of previous treatment history or bone marrow transplant candidacy. Overall, it is well tolerated with few side effects that included peripheral neuropathy and infectious complications. Two patients originally determined to be not eligible for transplant improved sufficiently on CYBOR-D to become eligible and then went on to receive autologous bone marrow transplant. The retrospective nature and small sample size limit this study, and prospective, randomized studies are needed to further elucidate the role of this regimen in AL amyloidosis. Disclosures: Stewart: Millennium Pharmaceuticals, Inc.: Honoraria, Research Funding; Celgene: Honoraria. Fonseca:Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy, Research Funding; Genzyme: Consultancy; Onyx: Research Funding; Otsuka: Consultancy; Medtronic: Consultancy.

Abstract Abstract 1876 Poster Board I-901 Background: Multiple Myeloma (MM) remains incurable in spite of new effective agents and combination regimens. SRC family kinases (SFK) are potential targets for therapy in MM: Hck, Fyn and Lyn are implicated in IL6-induced proliferation. Dasatinib is a potent inhibitor of not only BCR-ABL, but also SFK, c-KIT, PDGFRb, and EPHA. In myeloma and endothelial cells (ECs) isolated from MM patients (pts), dasatinib blocked proliferation, survival, adhesion, migration, and angiogenic potential, through a combined targeting of PDGFRβ as well as VEGF-triggered phosphorylation of SRC. Lenalidomide has clinical efficacy in the treatment of multiple myeloma (MM) as a single agent and in combination with dexamethasone. The combination of dasatinib, lenalidomide and dexamethasone exhibits synergistic inhibition of MMIS cells. Methods: The primary objective of this Phase I, multicenter, open-label, non-randomized study was to determine the maximum tolerated dose (MTD) of the combination of dasatinib, with lenalidomide and dexamethasone in pts with relapsed or refractory (RR) MM. Secondary objectives were to assess the tolerability of the combination, to establish the dose for future clinical investigations, and to assess the efficacy by International Uniform Response and EBMT Criteria. Pts ≥18 years with confirmed RR MM, measurable disease (at least 1 g/dL for IgG or 0.5 g/dL for IgA in serum or urinary excretion of 200 mg monoclonal light chain/24 hours), and at least one prior treatment were enrolled sequentially into increasing dose cohorts (using a 3+3 design). Pts received oral dasatinib daily on a continuous schedule, oral lenalidomide daily for 21 days, and oral dexamethasone 40 mg/day (Days 1, 8, 15, and 22). Cycles were repeated every 28 days. Dose-limiting toxicities (DLTs) were assessed in the first cycle. If there was no DLT, dose escalation continued to MTD, followed by an expansion phase of the established dose. Results: Enrollment is ongoing. 16 pts (6 M, 10 F; median age 70.5 years, range 51–80) were treated in cohorts 1, 2, 3 and 4; MTD has not been established (as by July 2009). The median number of prior lines of therapy was 3 (range 1–6). Seven pts had prior autologous stem cell transplantation; 8 pts had prior thalidomide, 4 prior lenalidomide and 3 pts both. Baseline β2 microglobulin levels of >3.5mg/L were reported in 4 pts. The most common (310%) treatment related adverse events (AEs) diarrhea 6 (38%); nausea 4 (25%); constipation 2 (13%); stomatitis 2 (13%); asthenia 3 (19%); weight decrease 5 (31%); dyspnea 2 (13%); rash 2 (13%); vertigo 2 (13%); insomnia 2 (13%). The most common grade 3 / 4 hematologic AEs included neutropenia 6 (38%), anemia 4 (25%) and thrombocytopenia 3 (19%). Two DLTs were identified in cohorts 1 and 4: 1 pt had 2 point decline in ECOG Performance Status and other pt had a drug interruption > 15 days due to nausea and vomiting, respectively. Six out of 16 pts discontinued treatment: 1 due to death in first cycle (D19); 3 for AEs (2 study drug related and 1 unrelated), 1 withdrawal of consent, 1 following maximal clinical benefit (minor response) after 12+ cycles. As of July 2009, 10 pts remain on treatment, with a median duration of treatment of 4.2 months (range 0.6–12). Responses were observed in 13 pts: 8 partial responses (PR), and 5 minor responses (MR). 1 pt had stable disease (SD) and 2 pts were not evaluable (1 pts died before completion of cycle 1 and other pt was too early for assessment). Conclusion: Dasatinib in combination with lenalidomide and dexamethasone is well tolerated and preliminary activity has been observed. Disclosures: Facon: Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen Cilag: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees. Stewart:Takeda-Millenium, Celgene, Novartis, Amgen: Consultancy; Takeda, Millenium: Research Funding; Genzyme, Celgene, Millenium, Proteolix: Honoraria. Garzon:BMS: Employment. Bleickardt:BMS: Employment. Gialelis:BMS: Employment. Tuozzoli:BMS: Employment. Derreumaux:BMS: Employment. Sonneveld:Janssen-Cilag: Honoraria.

Abstract BACKGROUND: CD49d (a.k.a. alpha 4 integrin) plays a critical role in leukocyte trafficking, activation, survival, and facilitates interactions between leukocytes and stromal cells via VCAM-1 and fibronectin. We and others have previously reported that CD49d gene expression in CLL B-cells correlates with CD38 expression (Durig Blood101:2748; Pittner Leukemia19:2264). We have also confirmed CD49d protein expression correlates with CD38 protein expression on CLL B cells (Pittner Leukemia 19:2264). Notably, one small study reported that CD49d expression may relate to overall survival among CLL patients independent of CD38 status (Zucchetto, Leukemia 20:523), although the relationship to other prognostic markers, such as ZAP-70 and cytogenetic abnormalities, was not evaluated. METHODS: We measured CD49d expression by flow cytometry in 130 patients with CLL (NCI 1996 criteria), accrued to observational studies at Mayo Clinic, between 1994 – 2006. CD49d expression was measured by 2 color flow cytometry using antibodies specific for CD19 (BD Biosciences) and CD49d (BD Pharmingen). CD49d expression was compared to level of CD38 expression, ZAP-70 expression, and degree of IgVH gene mutation (all treated as continuous variables). We also evaluated the relationship between CD49d expression and time to treatment (TTT) and other prognostic parameters, using the previously published 30% threshold to classify CD49d expression (Zucchetto, Leukemia 20:523). Finally, we evaluated the relationship between CD49d expression and in vitro sensitivity to fludarabine (1 um x 24 hrs) and chlorambucil (1um x 24 hrs) in a subset of 70 patients. RESULTS: The percent of B-cells expressing CD49d varied from 0.3 to 99.4% among the 130 patients tested (median expression= 6.1). The level of CD49d strongly correlated with the expression of ZAP-70 (r=0.34; p<0.0001) and CD38 (r=0.65; p<0.0001), as well as the degree of IgVH gene mutation (r=−0.29; p=0.006). The relationship between CD49d expression and other prognostic parameters using the previously published 30% threshold to classify CD49d expression is shown in Table 1. The median time to treatment for patients with low CD49d expression was 14.9 years compared to 5.4 years for those with high CD49d expression (p=0.008) High CD49d expression was correlated with in vitro resistance to chlorambucil (r=0.27, p=0.03) but not fludarabine (r=0.20, p=0.09). CONCLUSION: CD49d expression varies on CLL B-cells and relates to other prognostic parameters and TTT as well as in vitro sensitivity to chlorambucil. Since CD49d facilitates interactions between CLL B-cells and stromal cells, the association of this marker with poor prognostic features and in vitro drug resistance may relate to enhanced stromal nuturing of leukemic cells with higher CD49d expression. Additional studies are needed to determine whether CD49d expression may be clinically useful as a prognostic test or to predict response to treatment in patients with CLL. CD49D low CD49D high P value % ZAP70+ 33.0 75.0 <0.0001 % IgVH unmutated 24.3 55.6 0.02 %CD38+ 12.8 63.9 <0.0001 FISH <0.0001 %with 17p- or 11q- or 6q− 9.2 25.0 % with +12 5.8 43.8 %with normal or 13q− 85.1 31.3 Current Stage 0.17 0 30.9 16.7 I-II 67.0 77.8 III-IV 2.1 5.6

Abstract Abstract 487FN2 Background: Given the life-threatening nature of severe VOD (sVOD) and multi-organ failure (MOF), DF was made available in the US through a prospective treatment IND protocol (T-IND) to gather additional safety and response data from SCT patients (pts) with sVOD who were not eligible for a pivotal Phase 3 trial. Following completion of this Phase 3 trial, the T-IND protocol has continued and been amended to include pts who would have met eligibility criteria for the completed phase 3 trial, as well as pts with non-severe VOD and non-SCT pts who develop VOD after chemotherapy (chemo). This is the largest prospective evaluation of DF for the treatment of sVOD/MOF post SCT and non-SCT pts to date. Methods: Pts were initially required to have a diagnosis of VOD by Baltimore criteria (total bilirubin > 2.0 mg/dL with > 2 of the following: hepatomegaly, ascites or 5% weight gain) with MOF (either renal and/or pulmonary failure) that followed SCT. Following treatment of 104 pts, an amendment expanded eligibility criteria to include pts with VOD after chemo and pts with non-severe VOD (defined as no MOF). Key exclusion criteria included clinically significant bleeding or >1 pressor to maintain BP. CR was defined as bilirubin < 2 mg/dL + resolution of MOF (if applicable). Mortality was assessed at Day +100 (D+100) in all pts. DF was given at 6.25 mg/kg IV q6h (25 mg/kg/d) with treatment duration recommended for at least 21d. Results: This interim analysis is based on 269 pts enrolled between December 2007 and March 2011 at 67 centers. Nearly all pts (n=251) had undergone SCT (with allogeneic SCT in 225, 90%); 18 developed VOD after chemo alone. Of the 269 cases of VOD, 200 were severe at study entry, with 25% (66/269) of all pts dialysis dependent and 31% (83/269) ventilator dependent. Median age was 16 years (range 0.1 – 70); 55% were male. In the SCT pts, the most common diagnosis was leukemia (29% AML; 22% ALL; CML 3%; 4% other), with conditioning of CY (71%), BU (46%) and TBI (38%) respectively; 18% had undergone multiple SCTs (>1 SCT). Median onset of VOD was 15 d post-SCT. When presenting after chemo alone (n=18), median onset of VOD was 16 d after the first dose, most frequently after CY (61%), cytarabine (44%) and vincristine (39%), and for treatment of leukemia (AML 33%, ALL 33%, other 6%). Overall mean number of days of DF administration in all pts was 22 (range 1–88).Of 269 pts, 32% (85/269) achieved a CR and 50% [ by Kaplan-Meier estimate] survived to D+100. In the subgroup of SCT pts, 31% (78/251) achieved CR and 50% survived to D+100; 134 pts met entry criteria for the original Phase 3 trial and comparison to the Phase 3 historical control showed a statistically improved outcome in CR (30% vs 9%, p=0.0006) and D+100 survival (46% vs 25%; p=0.006). Of 200 pts with sVOD, CR was 28% and D+100 survival was 44%. In the 18 chemo only pts, CR was 39% and D+100 survival was 50%. CR rate and D+100 survival for the 69 pts with non-severe VOD were 42% and 62%, respectively. Delay of >2 d (vs < 2 d) in the start of DF after VOD diagnosis resulted in reduced CR (23% vs 35%, p=0.0339) and survival (37% vs 56%, p=0.01). Children as compared to adults had higher rates in CR (35% vs 29%) and survival (55% vs 43%). Toxicity proved generally manageable: 22% of pts experienced a total of 81 related AEs, primarily consisting of hemorrhage (19%) and hypotension (4%). Hemorrhage included pulmonary bleeding (6%), GI hemorrhage (3%), epistaxis (3%) and hematuria (3%). Similar to the observation of decreased GvHD in other studies, the incidence of all grade GvHD in the allogeneic SCT pts was 8%. Conclusions: In 269 pts with mainly sVOD/MOF, DF therapy achieved significantly improved outcome compared to an untreated historical control. Importantly, CR and survival were improved in pts who were treated within 2d of VOD diagnosis (vs. later) and in pts who had not yet progressed to sVOD. As with prior studies, there was a low incidence of DF-associated toxicities. Interestingly, the incidence of GvHD in allo-SCT pts was low, consistent with the reduction of GvHD seen in the large randomized EBMT pediatric prevention study. These results confirm the findings of previous trials and strongly support early intervention with DF once the diagnosis of VOD is made after SCT, as well as its use in pts who have not progressed to advanced MOF. The use of DF for VOD following intensive chemotherapy without SCT also appears promising, but more research in this patient population is needed. Enrollment to the T-IND study continues. Disclosures: Richardson: Gentium: Membership on an entity's Board of Directors or advisory committees. Arai:Gentium: Research Funding. Symons:Otsuka Pharmaceuticals: Research Funding. Martin:Gentium: Research Funding. Massaro:Gentium: Consultancy. D'Agostino:Gentium: Membership on an entity's Board of Directors or advisory committees. Hannah:Gentium: Consultancy. Tudone:Gentium: Employment. Hume:Gentium: Employment. Iacobelli:Gentium SpA: Employment. Soiffer:Gentium: Honoraria.

Abstract The standard of care for CLL is to treat only patients with obvious clinical progression because earlier intervention is not of proven benefit. The discovery of more accurate prognostic markers for CLL could change that paradigm. The predictors of more aggressive disease include 17p13 deletion (17p13−), 11q22-3 deletion (11q22−), unmutated (UM) immunoglobulin heavy-chain variable region (IgVH), and expression of ZAP-70 and CD38. In addition, monoclonal antibody (MoAb) therapies provide effective treatment with less toxicity than chemotherapy and are likely to be most efficacious in early stage CLL. The combination of alemtuzumab (ALEM) and rituximab (RIT) is of interest because of non-overlapping mechanisms of action. ALEM is also effective therapy for patients with defects in the p53 apoptotic pathway that are more resistance to purine analogue therapy. We tested the hypothesis that MoAb therapy with ALEM and RIT will eliminate/greatly decrease the high risk clone characterized by 17p13−, 11q22−, or UM IgVH plus either ZAP70+ or CD38+, in early stage CLL. Methods This trial will enroll a maximum of 30 patients and be considered promising if ≥ 19 patients respond. All patients with previously untreated CLL (Rai stage 0 −II) not meeting NCI-WG 1996 treatment criteria and with a high risk CLL clone were evaluated for enrollment. Treatment duration was 30 days (subcutaneous ALEM dose escalation, 3 mg - 10 mg - 30 mg on days 1–3) then 30 mg Monday, Wednesday and Friday for 4 weeks. RIT (375 mg/m2/dose IV x 4) was administered weekly staring on day 8. All patients received PCP and herpes virus prophylaxis and had CMV viral DNA testing for 7 months. Response was evaluated using NCI-WG 1996 criteria and minimal residual disease (MRD) was measured in peripheral blood using sensitive flow cytometry (1:104) for CD19+/CD5+/CD79b− lymphocytes. Results Since January 2005, 17 patients have been enrolled and the interim analyses are for the first 11 patients accrued. Median age was 62 years (29 – 75) with 6 males and 5 females. The qualifying high risk features were 17p13− (n = 4), 11q22− (n = 3), and UM IgVH + CD38+ +/− ZAP-70+ (n = 4). Median time from diagnosis to treatment was 11 months (2–72). Clinical stage (Rai) was 0 in 3 patients, I in 5 patients and II in 3 patients. Median absolute lymphocyte count was 25.6 x 109/L (15.9 – 81.8), Hgb 14.4 g/dL (12 – 15.8), and platelet count 171 x 109/L (125 – 312). Two patients had serious adverse reactions requiring intervention (CMV reactivation responsive to treatment; febrile drug reaction to sulfamethoxazole/trimethoprim). Grade 3–4 adverse reactions not requiring interventions were leukopenia (n = 4), neutropenia (n = 2), anemia (n = 1), elevated ALT (n = 1), and skin reaction to ALEM (n =1). There were no “first dose” reactions. All patients responded to therapy with 5 CR (4 of these MRD negative), 3 nodular PR, and 3 PR. Median duration of response has not yet been reached at median follow up of 11.7 months (6.5 – 14.9). Patients with a MRD negative CR had recurrence of detectable MRD at 120 – 210 days after completing therapy but all remain in CR. One patient died off study of complications of a myeloablative allogeneic transplant for progressive CLL. Discussion ALEM and RIT is effective and tolerable therapy for early stage high risk CLL. All patients responded with 36% achieving a MRD negative CR but serial MRD assays showed that the CLL clone was not deleted. This promising, treatment requires further improvement.

Abstract CLL B cells have significant opportunity to interact with multiple tissue sites that are critical to the leukemic cell’s ability to survive. The marrow stromal elements (MSE) in B-chronic lymphocytic leukemia (B-CLL) are very likely one of the most frequently involved in this important cell-cell interaction. We have utilized a novel bone marrow biopsy technique (Alvi S, Leuk Res, 2001) that consistently generates robust and long-lived marrow stromal elements from B-CLL patients in order to study CLL B cell apoptosis status in relation to angiogenic factors. The latter angiogenic parameters were studied as we have previously detected both a VEGF based autocrine pathway for CLL B cells and found an extensive neovascularization in CLL marrows. Bone biopsy material from B-CLL patients (N=25) yielded active cell growth in vitro which expresses the features of marrow stromal constituents. Importantly, these marrow constituents were able to be sustained for several months (range, 3 – 52 weeks) and also could be transferred repetitively to new culture dishes. CLL B cells were able to spontaneously release VEGF and TSP-1 as we have previously published (Kay N, Leukemia, 2002). MSE from CLL marrow (N=5) were found to spontaneously secrete basic fibroblast growth factor (bFGF) 5.2 ± 0.9 pg/ml (mean ± one SEM), vascular endothelial growth factor (VEGF) 162 ± 48 pg/ml and thrombospondin-1 (TSP-1) 90 ± 26 ng/ml into the culture medium. Significant reduction in CLL B cell spontaneous apoptosis,measured by Annexin/PI incorporation (mean ± one SEM), was seen after exposure to the CLL MSE (N=6) both after 24 hours (i.e., Non exposed CLL B cells vs. MSE co-cultured CLL B cells was 70% ± 9 vs. 39% ± 10 respectively for 24 hours, p < 0.01) and 72 hrs (data not shown). Exposure to MSE also enhanced the in vitro drug resistance of CLL B cells to chlorambucil (C). Thus, for CLL B cells (n=5) cultured with CLL MSE and C (1μM) for 24 hours, apoptosis levels were reduced from 58.8% ± 7.8 for B cells without MSE compared to 39.8% ± 3.8 for B cells exposed to MSE. Apoptosis resistance enhancement for CLL B cells was found to be similar with normal marrow stromal elements and a stromal cell line (HS-5). Anti-apoptotic proteins detected by immunoblot were found to increase for CLL B cells exposed to stromal elements from bone marrow biopsies and included Mcl-1, Bcl-2, Survivin and XIAP. While Mcl-1 was found to increase, there was a decrease in Bcl-2 and Survivin detected by immunoblot when CLL B cells were exposed to the HS-5 cell line implying a different mechanism for apoptosis enhancement. When CLL B cells were added to CLL MSE for 24 hours, there was an increase in VEGF released into the culture medium (283 pg ± 114 for the co-culture vs. 14 pg ± 1.7 and 162 pg ± 48.8 for CLL B cells and MSE cultured alone respectively). In contrast co-culture of CLL B cells with MSE (24 hours) resulted in less TSP-1 in the culture medium than expected (106 ng ± 28.8 for co-cultured CLL and MSE cells vs. 89.5 ng ± 27.5 and 90.9 ng ± 26.4 for CLL B cells and MSE cultured alone respectively). This change in the ratio of pro- to anti-angiogenic factors favoring VEGF strongly suggests that CLL B cell interaction with stroma can facilitate an angiogenic switch and may be linked to disease progression. In addition, we have found that bone biopsies from B-CLL patients can generate long-term marrow stromal elements that are able to reliably enhance CLL B cell apoptosis resistance.