Rajkumar, S. Vincent

Abstract Abstract 1858 Systemic light chain amyloidosis (AL amyloidosis) is a condition where clonal plasma cells produce misfolded insoluble immunoglobulin light chains that deposit in various organs causing progressive organ dysfunction. Chemotherapy and autologous stem cell transplant (ASCT) when eligible is the standard treatment options for patients with AL amyloidosis. There are several studies who report long term outcomes of patient post ASCT. However, there is a paucity of literature describing the outcomes of patients who have received ASCT but have relapsed. We performed a retrospective study to assess the outcomes and treatment regimens employed following relapse after ASCT. Between 1996 and 2009, 410 patients received ASCT at the Mayo Clinic as first line therapy. Of those 410 patients 42 patients died within 3 months of transplant, 64 patients died without documented relapse, 158 patients were alive without documented progression, and 146 patients had documented progression. Those 146 patients are the subject of our study. The median time to hematologic relapse was 2 years (range: 0.2–15.5 years). At relapse, 59 patients were treated with IMiD based therapy, 36 with alkylator based therapy, 24 with bortezomib, 15 with steroids, and 5 with second ASCT. The respective hematologic response rates were 58%, 33%, 50%, 53%, and 60%. The remaining six patients were not evaluable for response for one other following reasons: organ transplants; no further therapy; inevaluable disease. With a median post relapse follow up of 3.6 years, the median overall survival (OS) from the first post ASCT relapse was 4.6 years. The median post transplant follow up was 6.1 years, the median OS for these patients was 7.3 years from the time of transplant. These data provide novel information about outcomes after SCT relapse, which should be useful not only for patients and doctors but also for investigators designing studies for salvage therapies post-transplant. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: Myeloma remains incurable due to a stem cell/proliferative component that responds poorly to standard treatments. We have shown that aberrant IL-1beta stimulates the generation of paracrine IL-6, a central myeloma growth factor. A Phase II trial was completed using IL-1 receptor antagonist (IL-1Ra/Anakinra), which inhibits paracrine IL-6 production, and low dose Dexamethasone (Dex), which decreases IL-1 levels through myeloma cell apoptosis, in patients with SMM/IMM. SMM/IMM patients are most likely to benefit from anti-cytokine therapy in order to delay/prevent the development of active myeloma. Methods: Patients that had ≥ 10% bone marrow plasma cells and/or an IgG or IgA M-spike ≥ 3 g/dL and did not require immediate chemotherapy were eligible. All patients received 100 mg of IL-1Ra SQ qd for 6 months unless clinical progression occurred. Non-progressors were allowed to continue on therapy with IL-1Ra alone. Low dose Dex (20 mg qweek) was added after 6 months of IL-1Ra or for evidence of clinical progression; the dose was adjusted based on response/toxicity. Results: To investigate the effects of IL-1Ra and Dex alone and in combination in vitro, we co-cultured IL-1beta transduced +/− myeloma cells with stromal cells +/− dexamethasone, IL-1Ra, or both for 48 hours and quantitated the percent apoptotic cells by flow cytometry and IL-6 production by ELISA. The results showed that: 1) IL-1Ra was superior to Dex at inhibition of IL-6 but caused no myeloma apoptosis; 2) Dex induced apoptosis was inhibited by IL-6 3) Dex and IL-1Ra combined induced maximal IL-6 inhibition and apoptosis of myeloma cells. In the clinical trial, data were available on 47 patients; smoldering (79%) / indolent (21%). All patients received IL-1Ra initially and 20/47 subsequently received IL-1Ra/Dex. Seven patients had a decrease in the plasma cell labeling index (PCLI), a marker of cell proliferation, on IL-1Ra alone which paralleled a decrease in the high sensitivity C-reactive protein (CRP). Interestingly, in one patient treated with Dex alone for 6 months, Dex induced a decrease in the M-protein and IL-1 levels, however, the PCLI and CRP values increased. The IL-1Ra/Dex combination has resulted in stability of disease in the majority of the 47 patients; 28 continue on therapy with a median overall progression-free survival (PFS) of 37.5 months. Four of the 47 pts achieved a minor response (MR) with IL-1Ra alone, and an additional 6 pts achieved a MR/PR after addition of dex. The continuous measure of % reduction in CRP was significantly associated with time to progression (p=0.02). Similarly, those patients who had a >5% decrease in serum M protein also had a longer PFS (p<0.001). Of note, 2 patients with high PCLI values of 6.4 and 3.0, characteristic of poor prognosis, responded with a reduction in the PCLI values and continue on combination therapy for 3 and 1.5 years, respectively with stable disease. Conclusion: Agents such as IL-1Ra that specifically inhibit paracrine IL-6 production are more effective at targeting the proliferative component than apoptosis inducing agents such as Dex; the combination may be especially useful in patients that have an elevated PCLI at presentation.

Abstract Abstract 1856 Background: Lenalidomide has proven to be a highly effective treatment in relapsed multiple myeloma (MM), particularly when used in combination with dexamethasone. However, over 30% of patients with myeloma have renal insufficiency and as lenalidomide is renally excreted, little information is available about its use in myeloma patients with impaired kidney function. Defining a safe and effective dose of lenalidomide in this context is critical. Objective: We undertook this study to establish the maximum tolerated dose of lenalidomide in three cohorts of patients with different levels of impaired renal function: Group A - patients with creatinine clearance (CrCl) between 30 and 60 mL/min, Group B - patients with CrCl <30 mL/min not on dialysis, and Group C - patients with CrCl < 30mL/min who are on dialysis. Secondary endpoints included response rate, progression free survival and overall survival. Methods: Eligible patients had previously treated MM with renal impairment defined as creatinine clearance < 60 mL/min measured within 21 days prior to registration. Patients previously treated with lenalidomide were required to demonstrate clinical response (any duration) or stable disease with progression-free interval of > 6 months from start of that therapy. All patients received dexamethasone 40 mg orally on days 1, 8, 15 and 22 of a 28-day cycle. Prophylactic anticoagulation consisted of either 81 mg or 325 mg per day of aspirin. Patients also received lenalidomide orally every 1 or 2 days on days 1 through 21 of a 28-day cycle, as described below (Table 1). Starting doses were as in US Product Insert. Dose escalation follows a standard 3+3 design. Results: There have been 23 patients enrolled into groups and cohorts as shown in Table 1. Median age was 73 (range 49–89) and 13 (57%) were women. ISS stage was advanced in all patients, 0 in stage 1, 4 (18%) in stage 2 and 19 (82%) in stage 3. The regimen was well tolerated. Indeed, the MTD has not been reached in any of the groups, as no DLTs have occurred to date. The most commonly reported clinical adverse events (all grades, independent of attribution) across all patients included infections, hyperglycemia, constipation, dizziness, hyponatremia, hypocalcemia and tremor. Hematological toxicities (grade 3–4) occurred in 13 out of 21 pts (62%), mostly neutropenia and thrombocytopenia. Grade 3–4 events at least possibly related to the regimen occurred in 70% and included pneumonia (26%) and otitis media (9%). Response was seen in 14 patients, resulting in an overall response rate of 61%. CR was seen in 1 patient (4%), VGPR in 2 patients (9%), PR in 11 patients (43%), and SD for 9 patients. With median follow-up of 15.5 months, median progression-free survival is 9.8 months and median overall survival is 22 months. Conclusion: Lenalidomide and dexamethasone is a safe and effective regimen in patients with multiple myeloma and renal insufficiency. It is also very well tolerated, although cytopenias are common but manageable. MTD has yet to be reached in each group, allowing for higher doses to be given than previously thought, including 25mg daily (for 21/28 days) in patients with CrCl 30–60 mL/min, 25 mg every other day (for 21/28 days) in patients with CrCl < 30 mL/min not on dialysis, and 10mg daily (for 21/28 days) in patients with CrCl < 30 mL/min on dialysis. These results will provide needed, clinically relevant dosing for lenalidomide in MM patients with renal insufficiency. Disclosures: Kaufman: Millenium: Consultancy; Onyx: Consultancy; Celgene: Consultancy; Novartis: Consultancy.

Abstract Abstract 3138 Background: Several recent reports have suggested that doxycycline can inhibit amyloid fibril formation in different in vitro and in vivo model systems. Doxycycline is the antibiotic of choice for infectious disease prophylaxis in patients with penicillin allergy, following autologous peripheral blood stem cell transplantation for various hematological malignancies. We examined the outcome of patients with light chain amyloidosis (AL) undergoing autologous stem cell transplantation to study the impact of doxycycline used as antibacterial prophylaxis. Patients and methods: We studied 455 patients who underwent autologous stem cell transplant (ASCT) for AL between March 1996 and December 2011. We excluded 44 patients who died of transplant related complications or did not survive beyond 100 days after transplant. Patient records were reviewed to ascertain the prophylactic antibiotic used. Survival was estimated using Kaplan Meier method and the survival curves were compared using log-rank test. Cox proportional hazard model was used to estimate the prognostic impact of different variables. Results: The median age of the patients was 58 years (range, 26–74); 290 (67%) were male. The median estimated follow up for the entire cohort was 73 months (95% CI; 66, 79) and 314 (69%) were alive at last follow up. Doxycycline was used a prophylaxis in 106 (23%) of the patients, with most of the remaining receiving penicillin. The usual reason for using doxycycline was a history of penicillin allergy. Hematological response to transplant occurred in 377 (87%) patients, and there was no significant difference between patients receiving doxycycline prophylaxis compared with the rest. The median OS for the entire cohort was 161 months (95% CI; 101, NR). The median OS for those receiving doxycycline prophylaxis was not reached compared with 113 months for the rest (P=0.09). Looking specifically at those patients with a hematological response, the median OS was not reached for the doxycycline group compared with 161 months for the rest (P=0.04, figure). There was no difference in the OS between the groups among those with no hematological response. The impact of the prophylaxis was independent of the number of organs involved as well as organ response to SCT. Conclusions: The results of the current study appear to demonstrate a survival advantage for patients with AL who receives doxycycline prophylaxis, in the setting of hematological response from SCT. The results are consistent with the data regarding the effect of doxycycline on amyloid fibril formation. These initial findings should form the basis of clinical exploration of doxycycline as an adjunctive therapy in patients receiving other standard therapies for AL. Such a study can further clarify if use of doxycycline for longer duration can be of additional benefit. Disclosures: Kumar: Cephalon: Research Funding; Novartis: Research Funding; Millennium: Research Funding; Celgene: Research Funding; Merck: Consultancy, Honoraria; Genzyme: Research Funding.

Abstract Abstract 2973 Eukaryotic translation initiation Factor 5A (eIF5A) has been implicated in the regulation of apoptosis and is the only known protein to be modified by hypusination. Hypusinated eIF5A is the predominant form of eIF5A in cancer cells. However, in its unhypusinated form, eIF5A is pro-apoptotic. SNS01-T, designed to treat B-cell cancers, consists of two active components: a plasmid DNA expressing eIF5AK50R (human eIF5A containing a lysine to arginine substitution at position 50) which remains pro-apoptotic because it cannot be hypusinated, and an siRNA against an untranslated region of native eIF5A mRNA. When these two components are combined with linear polyethyleneimine (PEI), the nucleic acids are condensed into nanoparticles for protection from degradation in the blood and enhanced delivery to tissues. The eIF5AK50R transgene is under the control of the B29 promoter and enhancer, which restricts expression to B cells. The mode of action of SNS01-T is to use an eIF5A-specific siRNA to deplete the pool of hypusinated eIF5A in myeloma cells while simultaneously adding pro-apoptotic eIF5AK50R. In vitro cell studies and in vivo xenograft studies have demonstrated the efficacy of this approach. Eligible patients are enrolled sequentially into four cohorts of increasingly higher doses. Each cohort will receive SNS01-T by intravenous infusion twice weekly for 6 consecutive weeks and then be observed every 4 weeks during a 24-week follow-up period. Eligible patients must have been diagnosed with multiple myeloma according to IMWG criteria, have measurable disease, have relapsed disease after two or more prior treatment regimens, have a life expectancy of at least 3 months, and not be eligible to receive any other standard therapy known to extend life expectancy. The primary objective is to evaluate the safety and tolerability of multiple ascending doses of SNS01-T. Secondary objectives include pharmacokinetics, immunogenicity studies, proinflammatory cytokine quantitation, and therapeutic efficacy. The required number of 3 patients completed the dosing schedule in Cohort 1 from a total of 6 patients enrolled. Two of three patients had not progressed on treatment, based on standard response criteria including the monoclonal protein, and were considered stable at week 3 and week 6 the end of the dosing regimen. Three patients were withdrawn from the study by their physicians due to disease progression before completing treatment. One of the responding patients has continued to have stable disease at week 10, a month after the end of treatment with SNS01-T. The first group of patients received 0.0125 mg/kg, approximately 1 mg per patient by intravenous infusion. The planned dose levels for the second, third and fourth groups are 0.05, 0.2 and 0.375 mg/kg, respectively. The results to date of this first in man clinical trial indicate that SNS01-T was safely administered without dose-limiting toxicities in the first group of multiple myeloma patients. The MTD has not yet been reached. (Clinical Trials.gov Identifier: NCT01435720.) Disclosures: Hamadani: Celgene Corp: Speakers Bureau; American Cancer Society 116837-IRG-09–061–01: Research Funding; ASBMT & Millennium New Investigator Award: Research Funding; Conquer Cancer Foundation of ASCO: Research Funding. Barranco:Senesco Technologies: Employment. Thompson:Senesco Technologies Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Taylor:Senesco Technologies Inc.: stock options Other. Dondero:Senesco Technologies Inc.: Employment.

Abstract We and others previously demonstrated an increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first-degree relatives of multiple myeloma (MM) and MGUS patients, underscoring a familial component to this disease. However, MM is known to be a collection of cytogenetically distinct diseases, with 40-50% of MM cases having a reciprocal translocation involving the IgH locus on chromosome 14q32 and in many of the remaining patients, trisomies. In a small proportion of cases, both IgH abnormalities and trisomies are found in the same clone. These MM cytogenetic subtypes are associated with differential prognosis. Whether there are differences in familial risk by cytogenetic subtypes is not known. Patients with MM were recruited from the Mayo Clinic Hematology practice in Rochester, Minnesota (MN) between 2005 and 2015. Serum samples were collected from first-degree relatives and subjected to electrophoresis and immunofixation for MGUS determination. Age- and sex-specific rates of MGUS from the population-based Olmsted County, MN, prevalence study were used as expected rates for the calculation of risk ratios (RRs) for comparisons of first-degree relatives. Cytogenetic subtypes were classified by FISH testing performed in the clinic and categorized into groups defined by IgH translocation , trisomy, intermediate/ high-risk disease (t(4;14), t(14;16), t(14;20), and del17p). Further, the distribution of cytogenetic subtypes was compared between MM cases with and without evidence of MGUS in first degree relatives using Chi square tests. Analyses were also subset to MM probands diagnosed in MN. There were a total of 442 MM probands, with 1235 first-degree relatives recruited and eligible for the study. MGUS was detected in 78 relatives, for an age- and sex-adjusted prevalence of 6.1% (4.7%-7.5%). Analyses comparing prevalence of MGUS in first degree relatives to population-based rates from Olmsted County showed a 2.5-fold (95% CI=1.9-3.0) increased prevalence. When performing analyses among MN probands only (RR=2.9; 95% CI=2.1-3.8), results were similar. Of the 442 probands, 310 had FISH performed on plasma cells (identified by cIG staining; cIg-FISH) at diagnosis. Of these cases, 49% had a trisomy, 23% had an IgH translocation, and 9% had both. Although the proportion of trisomies and IgH translocations were 4-6% higher among MM probands with a relative with MGUS compared to those without, these differences were not statistically significant (Table 1). MM probands with a first degree relative with MGUS also had a similar proportion of cytogenetic subtypes that are considered of intermediate or high risk compared to those MM without a family history (26.9% vs 25.2%) (p=0.79) (Table 1). When restricted to MM probands from MN, results remained non-statistically significant (Table 1). We showed an increased risk of MGUS in first-degree relatives of MM cases, implying shared environment and/or genetics underlying this malignancy. However, we did not find an association between family history of MGUS in MM probands and the cytogenetic subtypes examined. Larger cohorts are needed to examine if a relationship exists between cytogenetic subtypes of MM and familial risk. Disclosures Kumar: Noxxon Pharma: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; AbbVie: Research Funding; Onyx: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Glycomimetics: Consultancy; Kesios: Consultancy; Janssen: Consultancy, Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Research Funding; BMS: Consultancy.

Abstract Background: Patients with monoclonal gammopathies typically have a single clone making a unique type of monoclonal protein, one heavy chain and one light chain. In a small proportion of patients, more than one (typically two) types of monoclonal protein can be seen and differ with respect to the heavy chain or light chain or both. There is limited information on the clinical course of patients with more than one monoclonal protein identified in their serum or urine. Objectives: We report outcomes of patients with more than one monoclonal protein at our institution over the past thirty years. Patients and Methods: We queried the existing clinical database to identify all patients with at least two different monoclonal protein types identified on serum or urine studies during the course of their disease. Retrospective chart review was performed on 551 patients, who had more than one type of monoclonal protein on electrophoresis and/or immunofixation. Results: Among the entire study cohort (N=551), 461 pts (84%) had a biclonal pattern, 7 (1%) had a triclonal pattern and the remaining 83 (15%) had a monoclonal pattern at the time of initial positive study. The median age at the time of initial diagnosis was 69.7 years (range; 32-93); 359 (65%) were male. Among these, 390 were diagnosed as MGUS/BGUS, 18 with SMM, 36 with MM, 20 with WM, and rest with another lymphoproliferative disorders. The median duration between the initial detection of monoclonal protein and the emergence of the biclonal protein was 40 months for the 83 patients, who were monoclonal initially. The distributions of the dominant monoclonal proteins were GK (30%), GL (21%), MK (22%), ML (9%), AK (9%), and AL (8%). The distributions of the second monoclonal proteins were GK (27%), GL (24%), MK (16%), ML (15%), AK (10%), and AL (7%). Overall, 20 patients with a MGUS/BGUS progressed to smoldering or symptomatic myeloma, while 12 patients with an initial diagnosis of SMM progressed to MM. The median estimated follow up for the MGUS/BGUS group and those with SMM were 6.5 years (95% CI; 5, 7) and 9.8 (95% CI; 4, 13), respectively. This translates to 20 progressions over 3822 person years of follow up for the MGUS/BGUS patient group and 12 progressions over 131 person years of follow up for the SMM group. The rate of progression was ~1% per year for patients with MGUS/BGUS and the median estimated time to progression was 2.6 years for the SMM group. (Figure). In majority of patients, the dominant M spike increased with the disease progression. Conclusion: Patients with biclonal gammopathies appear to have a similar rate of progression compared to what has been historically described for MGUS/ SMM population. For the patients who progressed and received treatment, both M proteins typically responded to therapy, and during relapse, the original dominant M protein typically reemerged as the dominant M protein. Figure 1 Figure 1. Disclosures Kumar: Janssen: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Sanofi-Aventis: Consultancy, Research Funding; Onyx Pharmaceuticals: Consultancy, Research Funding; Millennium: The Takeda Oncology Co.: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Skyline Diagnostics: Membership on an entity's Board of Directors or advisory committees.

Abstract Background: Among patients with immunoglobulin light chain (AL) amyloidosis, there is little consensus on when reinstitution of chemotherapy should occur (Milani and Dispenzieri, International Society of Amyloidosis 2016). AL amyloidosis patients who are treated with high dose chemotherapy followed by autologous stem cell transplant (ASCT) are a relatively low-risk and homogenous population, making them an ideal group to study practice patterns. Methods: We conducted a retrospective study to evaluate the patterns of relapse or progression and the timing of re-initiation of therapy among 146 patients who were initially treated with ASCT at Mayo Clinic between 1996 and 2009 and who received second-line therapy between 7/9/1997 and 4/12/2012. Results: The median time from ASCT to second-line therapy was 23.6 months and the median follow up post ASCT was 57.5 months. The indications for second-line treatment were: 1) both hematologic and organ progression 24.7% (36 patients); 2) organ progression only 41.1% (60); 3) hematologic relapse only 34.2% (50). The median dFLC at the time of starting second-line therapy was 10.5 mg/dL (1.6 - 59.5 mg/dL), which was 44.9% (13.8-167.2%) of dFLC level at diagnosis. Increase in proteinuria by > 50% from nadir (that was also at least 1g/24 hours, i.e. renal progression) was present in 35.8%. Increase in NT proBNP by >30% from nadir and minimum of 300 pg/mL was present in 48.9% of patients. The respective 4 years overall survival rates from the time of ASCT were 87.8%, 63.9%, and 56.7% (p=0.0016) for patients who had hematologic relapse, organ progression only and both organ and hematologic progression. Comparisons of laboratory markers at diagnosis, nadir of post ASCT and initiation of second-line therapy are listed in the table. Conclusions: Our study investigated the patterns of relapse / progression following upfront ASCT. This provides some insights on practice patterns of when physicians re-initiate therapy. Table Table. Disclosures Gertz: NCI Frederick: Honoraria; Celgene: Honoraria; Med Learning Group: Honoraria, Speakers Bureau; Research to Practice: Honoraria, Speakers Bureau; Novartis: Research Funding; Prothena Therapeutics: Research Funding; GSK: Honoraria; Sandoz Inc: Honoraria; Ionis: Research Funding; Alnylam Pharmaceuticals: Research Funding; Annexon Biosciences: Research Funding. Kumar:Millennium: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; AbbVie: Research Funding; Glycomimetics: Consultancy; Janssen: Consultancy, Research Funding; BMS: Consultancy; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Onyx: Consultancy, Research Funding; Kesios: Consultancy. Kapoor:Celgene: Research Funding; Amgen: Research Funding; Takeda: Research Funding. Dispenzieri:Prothena: Membership on an entity's Board of Directors or advisory committees; Alnylam: Research Funding; Celgene: Research Funding; Jannsen: Research Funding; pfizer: Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract Abstract 2948 Background: Deletions and mutations in the tumor suppressor protein p53 are an uncommon observation in new multiple myeloma (MM) patients and are observed more commonly in patients with advanced disease. p53 deletion has been observed to correlate with poor overall and progression free survival in MM patients. Wild type p53 modulates the expression levels of a broad array of proteins involved in cell cycle progression, apoptosis ultimately leading to cell cycle arrest and apoptosis. p53 is negatively regulated by MDM2. MDM2 binds to and ubiquitinates p53 marking it for proteasomal degradation. In addition, MDM2 is a direct downstream regulator of p53. Targeting the p53-MDM2 interaction by developing agents that bind to the p53 binding motif of MDM2 and reactivating p53 has therefore been an active area of research. Here, we present results from our pre-clinical studies using AT219, a small molecule inhibitor that binds to MDM2 preventing its interaction with p53. Methods: AT219 was obtained from Ascenta Therapeutics. Stock solutions were made using DMSO and working stock solutions were made using RPMI 1640 media containing 10% fetal bovine serum (20% serum for primary patient cells) supplemented with L-Glutamine, penicillin, and streptomycin. Akt1/2 kinase inhibitor (Akti) was purchased from Sigma. MTT assay was performed to study drug induced cytotoxicity and thymidine uptake was used as a measure to study differences in proliferation. Flow cytometry using Annexin V-FITC and propidium iodide (PI) was used to measure drug induced apoptosis in cell lines and patient cells. In addition, apo-2.7 was also used to measure apoptosis in patient cells. Mitocapture and cytochrome-c assays were also performed to confirm the induction of apoptosis in MM cell lines. In order to study the mechanism of action of the drug, immunoblotting studies were performed on lysates made from cell lines incubated with the drug for various time points. Results: AT219 induced potent cytotoxicity in MM cell lines MM1S, MM1R and H929, all three expressing wild type p53 with IC50 values of 2.5–5μM. Similar effects were observed when the above mentioned cell lines were treated with AT219 and the inhibitory effect of proliferation of these cells were examined. When MM1S or H929 cells were cultured with bone marrow stromal cells (BMSCs) derived from MM patients or with one of the three tumor promoting cytokines implicated in MM (IL6, IGF or VEGF) and treated with AT219, the drug was able to inhibit the proliferation of both cell lines to similar extents as observed when cultured independently without BMSCs or the cytokines. The increase in cytotoxicity was found to be due to cells undergoing apoptosis as observed when MM1S or H929 cells were cultured with AT219 and % apoptotic cells were measured as measured by annexin/PI, mitocapture and cytochrome c assays. AT219 was also observed to induce more potent apoptosis in primary cells obtained from new MM patients with wild type p53 than in cells obtained from relapsed MM patients with wild type p53. AT219 clearly upregulated p53 as observed by performing immunoblots after treatment with the drug in MM1S and H929 cells. In addition, MDM2 and p21 were also found to be significantly upregulated and Bax was slightly upregulated post drug treatment. Bcl2, Mcl1 and Xiap levels were down regulated. In MM1S cells AT219 treatment resulted in a slight down regulation of pAkt (Ser 473). However, in H929 cells we observed a transient upregulation of pAkt following AT219 treatment. This prompted us to test AT219 in combination with Akti on MM cell lines. Our results on both MM1S and H929 cells using AT219 in combination with Akti demonstrated synergy. We are currently testing this combination in primary cells drawn from MM patients with both wild type p53 and those with p53 deletions and mutations. Conclusions: Our studies validate the anti-MM activity of AT219 in MM patients with wild type p53. In addition to using AT219 in combination with Akti, we are testing AT219 in combination with existing anti- MM chemotherapeutic agents. Interesting results from our studies will form the basis for clinical evaluation of AT219 as a single agent or in combination with an Akt inhibitor or other agents in MM patients. Disclosures: Kumar: Celgene: Consultancy, Research Funding; Merck: Consultancy, Honoraria; Millennium Pharmaceuticals, Inc.: Research Funding; Novartis: Research Funding; Genzyme: Research Funding; Cephalon: Research Funding.

Abstract Introduction: For decades conventional skeletal survey (CSS) has been the standard imaging technique for the detection of bone impairment caused by Multiple Myeloma (MM). The development of cross-sectional imaging techniques like Whole Body Computed Tomography (WBCT) with or without Positron Emission Tomography (PET/PET-CT) and magnetic resonance imaging (MRI) led to the use of these techniques in several centers worldwide and to the implementation of their findings into the revised diagnostic criteria of MM. The aim of the current multicenter study was to compare sensitivity and prognostic significance of WBCT and CSS in patients with monoclonal plasma disorders. Methods: For the current retrospective analysis 308 patients with different stages of monoclonal plasma cell disorders from 8 centers were included. Compact discs with pseudonymized imaging data of WBCT and CSS were sent to the organizing center and uploaded to the picture archiving and communication system. In addition, questionnaires were completed by each center to collect clinical data of the patients. Image analysis was performed in consensus reading by three experienced radiologists (LAM, SD, VK) blinded to the clinical data of the patients. Osteolytic lesions in 19 pre-specified anatomic regions were characterized as "definitely present", "probably present", "probably absent" and "definitely absent". For the analysis only "definitely present" and "probably present" entries were counted as myeloma lesions. To define symptomatic or active versus smoldering myeloma based on the presence of bone lesions, findings of CSS were used to simulate the situation before the introduction of WBCT. For comparison of WBCT and CSS only those anatomic regions having valid measurements from both methods performed within 30 days without treatment in the meantime were considered. WBCT and CSS were tested for differences in detection sensitivity with the exact McNemar test. Results: Of 308 submitted datasets; 160 patients were without prior treatment and 56 of them had smoldering myeloma. Of 160 patients 80 (50%) had no osteolytic lesions on either CSS or WBCT and 33 (20.6%) showed osteolyses on both techniques. In 9 patients (5.6%) osteolyses were found on CSS but not in WBCT while 38 patients (23.8%) were positive on CT alone. Of note is that for some CT-scans, the upper extremities were not evaluable due to positioning during the examination. Odds ratio for osteolyses on WBCT compared to CSS was 4.22 (P < 0.0001). The regions where WBCT was most significantly superior in detecting osteolyses were the iliac bone, thoracic and lumbar spine as well as the ribs. CSS compared to WBCT revealed osteolyses in more patients only in the proximal extremities: for left humerus 10 (6.5%) versus 3 (1.9%), right humerus 12 (7.7%) versus 4 (2.6%), left femur 11 (7.1%) versus 7 (4.5%) and right femur 10 (6.5%) versus 8 (5.2%) respectively. Of 157 evaluable patients 63 (40.1%) showed osteoporosis (defined by radiological criteria) on both techniques while 29 (18.5%) had osteoporosis on WBCT only and 10 (6.4%) on CSS only (OR 2.90, P = 0.003). In the 56 patients with smoldering myeloma, with bone disease being defined according to the findings of CSS 12 (21.4%), were positive for osteolyses on WBCT (P = 0.0005). Conclusion: WBCT shows significantly more sites of bone destruction compared to conventional X-ray imaging particularly in skeletal regions composed primarily of trabecular bone while CSS shows more osteolyses in the appendicular skeleton - in part due to a limited field of view. More than 20% of patients with smoldering myeloma based on CSS have active disease that needs treatment based on WBCT. Therefore, WBCT is the current standard for the detection of osteolytic lesions in myeloma. The prognostic significance of WBCT and CSS findings for survival and correlation with clinical parameters will be reported at the meeting. Disclosures Hillengass: Celgene: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria; Novartis: Research Funding; Amgen: Consultancy, Honoraria; Sanofi: Research Funding. Plesner:Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Dimopoulos:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Genesis: Consultancy, Honoraria. Goldschmidt:Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Chugai: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Lentzsch:Celgene: Consultancy, Honoraria; BMS: Consultancy. Terpos:Takeda: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Genesis: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Novartis: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Honoraria.