Kumar, Shaji

Abstract NF-κB is a transcriptional factor promoting tumor cell growth and inhibition of apoptosis via regulating expression of proteins modulating cell cycle and anti-apoptosis. NF-κB is constitutively associated with an inhibitor (IκB), which is phosphorylated by IκB kinase (IKK) upon cell stimulation (ie, TNFα) and subsequently degraded by ubiquitin-proteasome pathway, thereby allowing NF-κB to translocate to nucleus. We have previously shown that an IKK inhibitor PS-1145 partially (20–50%) inhibits MM cell proliferation; however, it inhibits both IL-6 secretion from BMSCs triggered by MM cell adhesion and proliferation of MM cells adherent to BMSCs. Targeting IKKβ is therefore a possible therapeutic option for inhibition of MM cell growth in the bone marrow microenvironment by downregulating NF-κB activity. In this study, we further delineated the biologic significance of IKK inhibition in MM cells using IKKβ specific inhibitor MLN120B (Millennium Pharmaceuticals, Cambridge, MA). MLN120B induced 60–90% growth inhibition in cells from the MM cell lines RPMI8226, RPMI/Dox40, RPMI/LR5, U266, and INA-6; on the other hand, it induced only 25–30% inhibition in MM.1S and MM.1R cells, assessed by 72 h tritiated-thymidine uptake. Importantly, neither IL-6 nor IGF-1 overcomes the growth inhibitory effect of MLN120B in both MM.1S and U266 cells. Interestingly, MLN120B significantly augmented TNFα-induced cytotoxicity in MM.1S cells. We next examined whether MLN120B could enhance the cytotoxicity of other agents. MLN120B augmented growth inhibition triggered by doxorubicin and melphalan in RPMI8226 and IL-6 dependent INA-6 cell line. We therefore studied growth inhibitory effect of MLN120B in the presence of bone marrow stromal cells (BMSCs). MLN120B inhibited 70–80% of constitutive IL-6 secretion from BMSCs, without toxicity. Importantly, MLN120B almost completely blocked stimulation of MM.1S, U266 and INA-4 cell growth and IL-6 secretion from BMSCs induced by binding of tumor cells to BMSCs. Finally, MLN120B overcame the protective effect of BMSCs, cell adhesion mediated drug resistance, against dexamethasone in MM.1S cells. Taken together, our data demonstrate that an IKKβ inhibitor induces cytotoxicity in MM cells in the BM milieu, providing the framework for clinical trials of these novel agents to improve patient outcome in MM.

Abstract Abstract 4867 Introduction Both multiple myeloma (MM) and (AL) amyloidosis are clonal plasma cell proliferative disorders. While AL rarely “progresses” to MM, probably due to the shorter survival of AL patients, patients with MM have been reported to develop overt AL at a higher frequency. We conducted this study to identify and describe the clinical features, diagnosis, treatment patterns and response, and outcome among patients diagnosed with AL following an initial diagnosis of MM. Patients and Methods Of the 354 patients identified from a prospectively maintained database who carried a diagnosis of both MM and AL during the interval between January 1990 and December 2008, 44 patients had a histologic diagnosis of AL, at least 6 months after the diagnosis of MM. The organ involvement and treatment response (organ and hematologic) for AL as well as MM response to treatment were assessed according to conventional criteria. Results The median age at diagnosis of MM and AL was 63 years (range, 42-82) and 68 years (range, 45-86), respectively; 27 (61%) were males. The median time to AL diagnosis after MM diagnosis was 41 months (range, 7.6-134). The estimated median follow up from diagnosis of MM and AL is 15.5 years and 10 years, respectively and 39 (89%) patients have died. The median overall survival (OS) from diagnosis of MM and AL was 68.6 months and 9.1 months, respectively. At the time of AL diagnosis, 33 (75%) patients had developed typical features suggestive of AL [heart failure (12), paresthesias (11), nephrotic range proteinuria (9), elevated alkaline phosphatase and hepatomegaly (2), fatigue (7), weight loss (5), macroglossia (4) and periorbital ecchymoses (1)]; while others developed atypical features (3) (7%) or had an incidental finding of AL (8) (18%) [autopsy (2), unexplained cytopenia (2), mild proteinuria (1) and no symptoms (3)]. Cumulatively, amyloid deposits were revealed by biopsy of: bone marrow (23) (52%), subcutaneous abdominal fat (17) (39%), organ (10) (23%) and carpal tunnel tissue (6) (14%). Organ involvement, treatment response and hematologic status of MM at AL diagnosis were assessed for the evaluable patients. None, 1 and >1 organ involvement occurred in 5 (11%), 28 (64%) and 9 (20%) patients, respectively at AL diagnosis or follow up; while AL as the cause of neuropathy was questionable in 2. The organs involved were: heart (14, including 8 with >1 organ involvement), nerves (11), kidney (10), soft tissue (6), lung (5), GI (1) and liver (1). The hematologic status of MM at AL diagnosis included SD (22), progression (10), PR (3), VGPR (3) and not evaluable (6). The subsequent hematologic and organ response did not differ significantly among those who had a treatment change or started (20) (45%) compared with those who did not have a treatment change (20) (45%) at AL diagnosis [excluding those lost to follow up (2) or diagnosed at autopsy (2)]; although more patients (8/10) who had biochemically progressive MM belonged to the former group. The best hematologic response to treatment(s) after AL diagnosis (28) (64%) was: SD (17), PR (3), VGPR (6), CR (1), and progression (1); and not evaluable in others. The organ response (excluding patients with carpal tunnel surgery) to treatment(s) (18) (41%) was: progression (11), stable (4) and organ improvement (3). More patients with an improved (2/3) and stable (1/4) organ response had hematologic PR or better than those with progression (0/11) of organ disease. Five (11%) patients were alive at last follow up; and had either isolated kidney (3) and soft tissue (macroglossia) (1) or no organ involvement (1). All patients with an organ improvement, and 2/5 patients alive, had received PBSCT after AL diagnosis. Fewer patients with >1 organ involvement (1/9) underwent PBSCT compared with those without organ involvement (2/5); and achieved (0) PR versus (3) VGPR (to any treatment), respectively. Only 1/8 patient with an incidental discovery of AL developed symptomatic (cardiac) AL after 108 months of MM diagnosis and died; the remaining are either alive (1) or died from MM and its complications (3), infection (1), or were diagnosed at autopsy (2). Conclusion The recognition of AL (especially cardiac and multiorgan involvement) is critical in MM patients in order to determine prognosis and influence treatment. A high index of suspicion is required for the prompt recognition of AL to ensure timely institution of therapy with a goal of achieving hematologic and organ response. Disclosures No relevant conflicts of interest to declare.

Abstract Abstract 4228 Background Peripheral blood stem cells (PBSC) are the preferred graft type for autologous stem cell transplantation (ASCT) and mobilization is typically done using growth factor (GF) alone or a combination of chemotherapy (CTX) and GF. The success of mobilization is influenced by several factors such as prior therapy, mobilization strategy, underlying disease, among others. Patients (Pts) failing to mobilize successfully often have GF dose increased and if unsuccessful, mobilization is reattempted with chemotherapy + GF or G-CSF (Granulocyte Colony-Stimulating factor) + GM-CSF (Granulocyte–Macrophage Colony-Stimulating factor). More recently, plerixafor, a CXCR4 inhibitor, has been found to enhance G-CSF based collection allowing potential early intervention in poor mobilizers. However, this approach requires valid cut-points for peripheral CD34 counts (pCD34) for cost efficient use. Methods We studied 656 first time, G-CSF based PBSC mobilizers with Non-Hodgkin Lymphoma (562; 86%), or Hodgkin's Disease (94; 14%). Salvage attempts were excluded, as were first attempts using CTX+GCSF, plerixafor or GF combinations. Sensitivity-specificity analysis (Receiver operating characteristic) was used to define ideal cut-points for predefined outcomes. We used a CD34 yield of 2 million/kg as the minimum required collection and 5 million/kg as the ideal collection for the current analysis. Our current practice is to initiate collection at a pCD34 of 10/uL. Results We first determined the best day 1 pCD34 cutoff for being able to collect at least 2 million/kg PBSC to be 9/uL. Among those with ≥9/uL, only 6.6 % failed to collect at least 2 million compared to 55% among the rest (P < 0.001). These numbers were 6.3% and 50% respectively using the traditional cutoff of 10/uL. We then examined how the pCD34 on day 2 predicted collection, among those failing to reach the current threshold of 10/uL. Among this group, a pCD34 on day 2 of 9.1/uL was the best cutoff to predict a collection of 2 million/kg. Among those with >=9.1/uL, only 22% failed to collect at least 2 million compared to 79% among the rest (P < 0.001). Among those with day 1 pCD34 < 10, 49% achieved a count of 9.1/uL on day 2. We then examined what pCD34 on day 1 can best predict a pCD34 ≥ 9.1 on day 2 and found this to be 5.2/uL. Among those with day 1 pCD34 ≥ 5.2/uL, 79% reached day 2 pCD34 ≥ 9.1 compared to 24% among the rest (P < 0.001). We then determined cutoffs based on ideal targets using only those patients achieving pCD34 count > 10/uL by day 2, since these patients would have started collection without any change in the mobilization technique. We used a maximum of 5 collections to achieve the goal as being ideal, taking into account the most commonly used practice of collecting during weekdays. We examined cutoffs for a target of 5 million/kg for one transplant. The best day 1 or day 2 pCD34 predicting a 5 million/kg yield in 5 collections was 17/uL. Among those with day 1or 2 pCD34 ≥ 17/uL, 4% failed to reach 5 million in ≤ 5 days compared to 96% among the rest (P < 0.001). Conclusions This study provides an estimate of optimal pCD34 count thresholds for early identification of patients with lymphoma at high risk of collection failure. It is reasonable to use the first or second day pCD34 count, since a substantial proportion of patients will achieve the threshold value by day 2 and these patients appear to have similar outcome as those reaching the threshold by day 1. Based on the results here, interventions such as addition of plerixafor can be considered if pCD34 count is < 6/uL on day 1 or < 10/uL by day 2, to achieve the minimum collection of 2 million/kg. However, in order to achieve the ideal targets, a higher threshold should be considered and the recommendation based on the current study would be 17/uL for a target of 5 million. Such a target-adapted strategy may be more appropriate. Disclosures: Kumar: Celgene,Genzyme,Millenium,Novartis,Bayer,: Honoraria, Research Funding. Gertz:Genzyme: Research Funding. Micallef:Genzyme: Research Funding.

Abstract Abstract 3854 Poster Board III-790 Background Primary systemic amyloidosis (AL) is an incurable plasma cell disorder. Lenalidomide, especially in conjunction with dexamethasone, has been shown to be active in patients with multiple myeloma. Pomalidomide is a derivative of thalidomide that acts as an immunomodulator. Preliminary data in multiple myeloma demonstrate that this agent is highly active and well tolerated. Methods Eligible patients were accrued into an IRB approved treatment trial with pomalidomide and dexamethasone after signing informed consent. Pomalidomide (2 mg) and dexamethasone (40 mg) were scheduled to be taken orally, the former on a continuous schedule and the latter once weekly. All patients were instructed to take an aspirin daily. Patients were eligible if they had previously treated, biopsy proven, symptomatic AL. Patients were required to have measurable hematologic disease, defined as either a serum M-protein greater than 1 g/dL, a urinary M-protein greater than 200 mg/24-hours, or a serum immunoglobulin free light chain greater than 10 mg/dL. Other eligibility criteria included an ECOG PS>=2, adequate hematologic reserve (ANC>=1000/uL, platelets>=75/uL) and adequate renal function (creatinine <=2.5 mg/dL). They also were required to comply with contraceptive requirements. Patients were excluded if they had uncontrolled infection, another active malignancy, NYHA classification III or IV, a serum troponin T >0.1 ng/mL, >=grade 3 peripheral neuropathy, untreated active thrombosis, or other chemotherapy within 2 weeks of study enrollment. Thirty-four patients are to be enrolled to allow for 2 possible cancels and to provide 90% power to detect a true hematologic response rate of at least 20%. Between 11/24/08-7/28/09, 20 patients have been enrolled. Baseline characteristics and adverse events are available for 17 of the 20 enrolled patients. Results Median age was 63 years (range 52 78), with 60% male. The median time from diagnosis to study entry was 45 months (range 4.5-103). Eighty-two percent had cardiac involvement; 41% renal involvement; 18% peripheral nerve involvement; and 12% autonomic nerve involvement. The cardiac biomarker staging breakdown was: I, 13%; II, 56%; and III, 31%. Patients were heavily treated, with 100% having received prior alkylator (including prior transplant in 9), 44% prior lenalidomide, 31% prior thalidomide, and 37% prior bortezomib. Thirty-three percent of patients had non-hematological adverse events (AEs) >=grade 3 (severe) that were deemed to be at least possibly related to therapy. Thirty-three percent had >=grade 3 hematologic AEs. Neutropenia was most the most common severe hematologic AE; severe thrombocytopenia was observed in only 1 patient, and there was no severe anemia. The most common severe non-hematologic AE was fatigue, which was observed in 3 patients. The only other severe AEs, each of which was observed in one subject each, were pneumonia, weakness, dyspnea, and ascites. As of 8/14/09, 17 patients remain on active therapy. Median time on study is only 3.7 months (range 0.2-8.1). Three patients have discontinued therapy: two progressions; and one death 5 days into treatment, presumably due to cardiac amyloidosis. At the time of this writing response rates could not be calculated given the short follow-up, but hematologic responses have been observed, and details on efficacy will be presented at the meeting. Conclusions Pomalidomide is well tolerated in previously treated AL patients. More information about its activity will be provided at the meeting. Disclosures: Dispenzieri: Celgene: Research Funding. Gertz:Celgene: Honoraria. Kumar:Celgene: Research Funding. Rajkumar:Celgene: Research Funding. Witzig:Novartis: Research Funding. Greipp:Celgene: Research Funding. Fonseca:Celgene: Consultancy. Bergsagel:Celgene: Consultancy. Mikhael:Celgene: Research Funding. Roy:Celgene: Research Funding. Lacy:Celgene: Research Funding.

Abstract Abstract 534 Background: Light chain (AL) amyloidosis is characterized by deposition of amyloid derived from immunoglobulin light chains in various organs. Cardiac involvement can lead to a variety of manifestations including congestive heart failure (CHF), conduction disturbances, and arrhythmias, including sudden death. Patients (pts) with cardiac involvement, especially in the presence of CHF, have a poor prognosis. Autologous peripheral blood stem cell transplantation (SCT) is increasingly being used for AL and has been associated with high rates of hematologic and organ responses. However, cardiac involvement due to AL is also associated with higher rates of complications following SCT; and those with advanced cardiac involvement are rarely considered for SCT. As such, our study does not represent the full spectrum of pts with cardiac involvement due to AL, but only those who are considered transplant eligible. Patients and methods: Of the 382 pts with AL who underwent SCT at our institution between May 1996 and September 2008, 194 had documented cardiac involvement. Six pts who underwent heart transplantation were excluded; and188 (49%) pts were considered for this study. Groups were compared using Fisher's exact test or t-test, and survival was calculated using Kaplan Meier method. Survival curves were compared using log rank test. Results: The median (range) age of pts at the time of SCT was 57.3 years (31-71); 122 (64%) were males. The median (range) duration from AL diagnosis to SCT was 3.6 mos (1-75). The estimated median follow up for the entire cohort was 44 mos (95% CI; 38-54) and 39 mos (95% CI; 32-51) from AL diagnosis and SCT, respectively. The estimated median overall survival (OS) for the cohort was 77 mos (95% CI; 38-86) and 69 mos (95% CI; 33-80) from AL diagnosis and SCT, respectively, and 107 (57%) pts were alive at the time of analysis. One, 2 or 3 organs were involved in 32 (17%), 106 (57%) and 50 (26%) pts, respectively. At the time of SCT, the median (range) septal thickness was 14 mm (9-25), and the median (range) EF was 63% (28-84). The cTnT/NT-ProBNP stage was availabel for 100 pts (6, 51 and 43 pts in stages 1, 2 and 3, respectively). Melphalan 200/m2 (85 pts) or Mel/TBI (10 pts) was used for conditioning in 51% pts, whereas the other half had reduced doses of melphalan (100-160 mg/m2). Thirty-one (16.5%) pts had died within 100 days of SCT. A hematologic response was obtained in 129 (69%) pts. A decrease in septal thickness was seen in 88 (47%) pts, with the median (range) decrease being 2mm (1-8). An increase in EF was seen in 85 (45%) pts and the median (range) increase was 6% (1-29). A conventional cardiac response (septal decrease > 2 mm or EF increase '20%) was seen in 62 (33%) pts. A decrease in NT-ProBNP was seen in 31 pts (90 with availabel values). The impact of hematologic or organ response on the OS from SCT was assessed only for those surviving beyond 100 days (landmark analysis). The median OS for those with a hematologic response (149 evaluable) was not reached (NR) compared with 22 mos for those with no response (P < 0.001) (fig B). The median OS for those with a conventional cardiac response was NR compared with 69 mos for those with no response (p=0.003) (fig A). The median OS for those with any decrease in NT-ProBNP was NR compared with 26 mos for those without any decrease (P<0.001). The best cutoff for NT-ProBNP decrease to predict pts being alive at 2 years was 55%, with all such pts alive at the time of analysis. A baseline troponin of <0.02 ng/ml or NT-ProBNP <5000 pg/ml best predicted the possibility of being alive at 1-year post SCT. Transient worsening of echocardiogram as well as cardiac biomarkers were seen in some pts who eventually improved. Eighty-one pts (43%) have died after SCT due to cardiac (37 pts) and non-cardiac (27 pts) causes; while the cause of death was not known in others. Conclusion: SCT is an effective approach in pts with cardiac involvement due to AL, with hematologic and cardiac responses seen in over two-thirds and one-thirds of the pts, respectively. Improved survival is associated with hematologic and organ responses. Cardiac biomarker improvement may be used as a measure of organ improvement and correlates with outcome. This finding will need to be confirmed in a larger group of pts, as well as with other therapies for AL. Disclosures: Lacy: Celgene: Research Funding.

Abstract Background: Multiple myeloma (MM) is characterized by accumulation of clonal malignant plasma cells in the bone marrow (BM). CD45 was initially characterized as a leucocyte common antigen and can be found on all hematopoietic cells and is a key regulator of antigen mediated signaling and activation in B and T-lymphocytes. The expression of CD45 appears to be heterogeneous among the plasma cells in MM and this characteristic has been suggested to have biological and prognostic significance. Goals: To study CD45 expression by flow cytometry (FC) on BM plasma cells from patients with different stages of MM, and compared CD45 expression to key clinical and biological characteristics including clinical outcome, labeling index (%S-phase), bone marrow angiogenesis, and bone disease. In addition, the expression profile of various adhesion molecules on CD45+ vs CD45− plasma cells was studied. Results: BM from seventy-five patients seen at the Mayo Clinic during 1995 and diagnosed with newly diagnosed MM (29), relapsed MM (17), smoldering MM (12), and MGUS (17) were studied for CD45 expression.. CD45+ was defined as >20% of gated plasma cells expressing CD45. A mean of 30% of the plasma cells expressed CD45 by flow cytometry (median, 14%; range, 0.1 to 100%). Among the entire cohort of patients, 33 (44%) of the patients were CD45+. Patients with early disease (MGUS and SMM) had a higher percentage of plasma cells expressing CD45 compared with patients with advanced disease (new or relapsed MM) (43% vs. 22%; P = 0.005). Among those with early disease 69% were CD45 positive compared to 28% among those with advanced disease (P = 0.0008). Among the 46 patients with advanced disease, the mean percentage of CD45+ plasma cells was 14% (range, 0.1 – 85) for those with bone lesions compared to 34% (2 – 99) for those with none; P = 0.02. Also, those with high labeling index (>=1%) had a higher percentage of CD45 expressing plasma cells than those with a low labeling index (30% for high LI vs. 15% for low LI; (P = 0.08). Among those with advanced disease, patients with low-grade angiogenesis had a higher percentage of CD45+ plasma cells; 31% vs. 13% (P = 0.03). The median overall survival for the CD45 positive group was 39 mos vs. 18 mos for the CD45 negative group, but the difference was not statistically significant (P=0.1). The expression of CD138 (syndecan-1), CD56 (NCAM) and CD54 (ICAM-1) were higher among the CD45 neg plasma cells. Other adhesion molecules, especially LFA-1, Mac-1, VLA-5, and CD44 were more often expressed on the CD45 + plasma cells. Conclusions: This study demonstrates that CD45 expression is more common in early disease and is lost with disease progression. There are important immunophenotypic and biologic differences in the CD45+ vs CD45− plasma cells that may have implications for the design of immunotherapy for MM.

Abstract Abstract 615 Background: Trials comparing efficacy of standard melphalan prednisone (MP) therapy with MP plus thalidomide (T) in the transplant ineligible, elderly patients with multiple myeloma have provided conflicting evidence. While there is greater agreement with regard to superior response rates (RR) with the addition of T to MP in elderly patients, the impact on progression free survival (PFS) and overall survival (OS) is less clear with some trials showing an improvement in PFS and/or OS with MPT and others demonstrating no difference in outcomes. We performed a systematic review to integrate the existing outcome data related to the efficacy of MP vs. MPT using a meta-analytic approach. Methods: A comprehensive search of electronic database through July 31st, 2009 was performed for publications, abstracts and presentations to identify randomized controlled trials (RCTs) comparing MP with MPT. A meta-analysis was performed by pooling results on clinical endpoints of RR, PFS and OS reported in all the identified RCTs under a random effects model. We did not have access to individual patient data from these trials. Results: Overall, five prospective RCTs (3 published articles and 2 abstracts) comparing MP with MPT regimen and comprising a total of 1571 patients were identified. For the endpoints of OS and PFS, data were extractable only from 4 RCTs (abstract by Gulbrandsen et al. was excluded). The Bregg and Egger funnel plot for OS demonstrated a symmetric distribution (P = 0.6) indicating no significant publication bias. The test of heterogeneity among all RCTs was statistically significant in the estimate of RR (tau2=0.21; chi2=16.33; p=0.003 (df=4); I2 = 75.5%), but not significant for the estimates of PFS (tau2=0.01; chi2=4.61; p=0.2 (df=3); I2 = 34.9%), and OS (tau2=0.02; chi2=5.53; p=0.14 (df=3); I2 = 45.8%). As expected, the pooled odds ratio of responding to treatment with MP versus MPT was 0.307 (P&lt;0.001) indicating that MP was worse than MPT in achieving at least a partial response. The pooled hazard ratios (HR) for PFS and OS were 1.59 (p&lt;0.001) and 1.34 (p=0.006), respectively (see table for forest plots) in favor of MPT. Conclusion: Our meta-analysis implies that in previously untreated, transplant ineligible elderly patients with multiple myeloma, the addition of thalidomide to melphalan-prednisone demonstrates improved RR, PFS and OS compared with the use of melphalan-prednisone alone. Although the results from a comprehensive individual patient data pooled analysis would give a more precise estimate, our analysis suggests that MPT is superior to MP in terms of response and survival. Disclosures: Dispenzieri: Celgene: Research Funding. Gertz:Celgene: Honoraria. Kumar:celgene, genzyme, millennium, novartis, bayer: Research Funding; genzyme: Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 54 Despite its curative potential, the role of allogeneic stem cell transplant (allo-SCT) in MM has been limited by high treatment related mortality (TRM). Autologous stem cell transplant (auto-SCT) thus remains the standard of care for eligible patients (pts) with MM. Recently interest in allo-SCT has been increasing due to the incurable nature of MM, better risk stratification models, improved supportive care and finally the increasing experience with less toxic reduced intensity conditioning. We analyzed the trends in practice of allo-SCT for MM over the past two decades. A total of 1211 pts undergoing allo-SCT for MM between 1989 and 2005, reported to the CIBMTR were analyzed in three cohorts based on year of allo-SCT: 1989–1994 (n=346), 1995–2000 (n=285), and 2001–2005 (n=580). Probabilities of progression-free survival (PFS) and overall survival (OS) and cumulative incidence estimates of TRM and relapse were calculated. Patient characteristics are summarized in table 1. Patients transplanted in the later cohort (2001–2005) were of higher age with 53% above age 50 years (vs. 12% in 1989–1994). There was decreasing use of myeloablative regimens and bone marrow grafts over time (82% vs. 62% vs. 9% for myeloablative regimens and 99%, 62% and 13% for marrow grafts respectively). Increasing number of pts in the later cohort received an auto-SCT prior to allo-SCT (Table 1). The proportion of unrelated allo-SCTs increased over time (5% vs. 21% vs. 33%). Graft versus host (GVH) prophylaxis changed over time with increasing use of cyclosporine with agents other than methotrexate and increasing use of ATG in the recent years. Median survival increased over the three time periods from 1989 – 2005: 11.1 months (mos.) vs. 12.2 mos vs. 20.3 mos. The 100 day mortality decreased steadily over successive time periods; 35% (95% CI; 29–31), 29% (24–35) and 19% (16–23) respectively. Similarly, the TRM at 5 years remained steady between the first two periods, but decreased in the last period (40 & 48% vs. 29%). The incidence of chronic GVHD increased in the later cohort but the incidence of acute GVHD was similar over the years. While PFS was the lowest for the most recent group (15% at 5 years), the overall survival at 5 years was similar among the groups (30, 32, and 29 mos). Long term PFS at 10 years was 18% in the 1989–1994 cohort and 17% in 1995–2000. Long term OS at 10 years was 23% in 1989 – 1994 and 1995–2000 cohorts. Results are summarized in table 1. A clear trend towards reduced intensity conditioning, unrelated donor SCT, use of PBSC grafts and selection of older patients was noted. There was increasing use of tandem auto-allo SCT with an increasing proportion of patients with a prior auto-SCT. While the TRM has decreased significantly in the last cohort, this did not translate into an improvement in survival primarily because of increased risk of relapse in the latter cohort. Long term (>10yr) progression free survival which may approach a cure has remained unchanged over the past two decades at <20%. Disclosures: Lonial: Celgene: Consultancy; Millennium: Consultancy, Research Funding; BMS: Consultancy; Novartis: Consultancy; Gloucester: Research Funding.

Abstract Abstract 3853 Poster Board III-789 Background Light chain (AL) amyloidosis is a clonal plasma cell disorder characterized by progressive multiorgan deposition of amyloid fibrils derived from immunoglobulin light chains. Treatment strategies for AL have typically targeted the clonal plasma cell and have paralleled that for myeloma, with recent clinical trials evaluating the role of novel agents such as immune modulatory drugs (IMiDs). Lenalidomide has activity in patients with AL, and given the synergy seen with alkylating agents, we designed a phase 2 clinical trial of cyclophosphamide added to lenalidomide and dexamethasone. Methods Patients (Pts) with newly diagnosed or previously treated AL, with adequate hematological and organ function, were enrolled between December 2007 and November 2008. Treatment consisted of 28-day cycles with Lenalidomide at 15 mg daily (days 1-21), oral cyclophosphamide 300 mg (days 1, 8, 15) and dexamethasone 40 mg weekly. All patients received aspirin for thromboprophylaxis. Hematological and organ responses were assessed using conventional response criteria. Results Thirty-five pts, 11 (31%) previously treated, with a median age of 64 yrs (range 44-82) were enrolled. Median time from diagnosis to trial enrollment was 1.6 mos (range; 0.1- 129) and 23 (66%) were alive at the time of analysis with a median follow up of 8.7 mos (range; 1.5-17.6). Three or more organs were involved in 10 (28%) pts with cardiac and renal involvement present in 22 (63%) and 27 (77%) respectively. Fifteen pts (44%) had advanced stage III disease by the troponin/ NT-ProBNP staging system. Seven (20%) pts had previous stem cell transplant, one pt had thalidomide and others had melphalan, dexamethasone or a combination of the two. The median duration on study was 6.5 months and the median number of cycles administered was 6, with 27 (77%) patients completing at least 3 cycles of therapy. Thirteen patients still remain on study, with the most common reason for study discontinuation being toxicity (10 pts, 45%). There were 15 (43%) and 24 (69%) episodes of Grade 3 or 4 hematologic and non-hematologic adverse events respectively. The most common non-hematologic toxicities seen were fatigue, edema, constipation and rash. Six patients died while on study due to sepsis (1), multiorgan failure (1), arrhythmia (1), or heart failure (3). The overall hematologic response rate was 60% (21 pts; CR (2), VGPR (10) and PR (9)); 79% for stage I and II pts and 40% for stage III patients. Among those patients receiving at least four cycles, the response rate was 20/23 (87%); 2CR, 10 VGPR and 8 PR. At least one organ response was documented in 8 (24%) patients. The median overall survival (OS) for all enrolled patients is 16.1 mos (95% CI; 10.8-NR). The median OS was not reached for stage I and stage II patients, and was 7 mos (95% CI; 4.6 - 16.1) for stage III pts. The median time to hematologic progression was 16.1 mos and to hematologic or organ progression was 6.7 mos (95% CI; 6.3, 16.1). The median OS among those with a hematologic response was 16.1 mos, and not reached among the group with a VGPR or better. Among the 31 patients with measurable FLC, those (n=24) with a ≥50% decrease in the difference between light chains had superior OS compared to the rest (16.1 mos vs. 4.3 mos). The six patients who died on study all had cardiac involvement and significantly higher NT-ProBNP/ BNP compared to the rest. Conclusion The combination of cyclophosphamide, lenalidomide and dexamethasone has significant activity in patients with light chain amyloidosis. Toxicity is manageable with dose reductions, but patients with advanced cardiac involvement are at a higher risk for toxicity and early discontinuation of therapy. Future trials with this combination should compare this regimen with other treatment approaches in selected patients, as well as pursue a dose-adapted strategy in those with advanced cardiac involvement. Disclosures: Kumar: CELGENE: Research Funding; MILLENNIUM: Research Funding; BAYER: Research Funding; GENZYME: Research Funding; NOVARTIS: Research Funding. Gertz:celgene: Honoraria; millenium: Honoraria, Membership on an entity's Board of Directors or advisory committees. Dispenzieri:Celgene: Research Funding.

Abstract Angiogenesis or formation of new blood vessels from existing blood vessels, in contrast to vasculogenesis or de novo formation of new vessels, plays an important role in the progression and spread of most cancers. Multiple myeloma (MM) is characterized by increased microvessel density (MVD), a quantitative estimate of angiogenesis, which correlates with stage of disease. MVD increases with progression from MGUS to smoldering MM to newly diagnosed MM and relapsed MM. It is a powerful prognostic factor, predicting for overall survival. To further elucidate the biological basis for the prognostic value of increased angiogenesis in MM, we studied the interactions of MM cells with endothelial cells using HUVECS as a model system. Co-culture of MM cells (MM1.S, OPM2, U266) with HUVECS induced tumor cell proliferation. Enhanced tumor cell proliferation correlated with the number of HUVECs and was greater than that triggered by co-culture with patient bone marrow stromal cells. When HUVECs were fixed prior to co-culture there was a significant decrease in the tumor cell proliferation. Addition of HUVEC conditioned media to the MM cell lines also induced proliferation. Importantly, HUVECS protected against anti-MM agents including conventional agents (Dexamethasone, Doxorubicin, Melphalan) and novel drugs (Revlimid™). The protective effect afforded by co-culture was lost on HUVEC fixation. Intracellular signaling events following MM cell-endothelial cell contact were studied to understand the mechanisms of the proliferative and protective effects. Western blotting demonstrated activation of the JAK/STAT, PI3K/Akt and the MAPK pathways, mediating proliferation and survival. Ongoing studies focused on understanding cytokine as well as adhesion-mediated interactions between the endothelial cells and the MM cells will identify targets for new therapeutic approaches in MM.