Citations

Abstract Abstract 4000 Background: We have previously reported that there is an increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first-degree relatives of patients with multiple myeloma (Vachon CM. Blood 2009 114: 785–790). There are several cytogenetic subtypes of myeloma, and there are no data on whether certain cytogenetic subtypes of myeloma are more frequently associated with familial MGUS. Methods: We studied patients with myeloma who participated in the familial MGUS study in whom presence or absence of MGUS in the first-degree relatives had been ascertained (Vachon CM. Blood 2009 114: 785–790). Probands were seen at the Mayo Clinic Hematology/Oncology practice (Rochester, MN, USA) between February 2006 and September 2007. Cytogenetic data was acquired via electronic medical record abstraction of fluorescence in-situ hybridization (FISH) lab reports, and used to categorize patients into one of nine cytogenetic subgroups: trisomy(ies), t(6;14), t(11;14), t(4;14), t(14;16), t(14;20), Mixed (those with trisomy(ies) and an IgH translocation), other cytogenetic abnormalities (in the absence of trisomy(ies) or IgH translocation), and normal (Kumar S. Blood 2012;119:2100–2105). We examined whether a difference in the distribution of the six primary cytogenetic categories of myeloma existed between probands with a family history of MGUS and/or myeloma and those without. Results and Conclusions: Of the 248 patients invited to participate, FISH data (with sufficient plasma cells) was available on 119 participants to establish the primary molecular cytogenetic classification of myeloma. All had available information regarding family history of MGUS and multiple myeloma. 27 had an affected first-degree relative with MGUS, and 92 did not. Distributions of cytogenetic subtypes in the two groups are shown in Table 1. IgH translocated MM was more common in myeloma patients who lacked an affected first-degree relative compared to those with familial MGUS (19% vs 30%, P=0.32) Interestingly, the t(11;14) subtype was more common in myeloma patients without familial MGUS compared to those with an first-degree relative with MGUS (19.6% vs 7.4%, P=0.24). The differences in Table 1 did not reach statistical significance, possibly due to the small numbers of individuals with a family history in this sample. However, the distribution (Table 1) suggests that the distribution of cytogenetic subtypes may be different in myeloma that is not associated with familial MGUS compared with myeloma in which a familial tendency is detected. IgH translocated MM appears to have a lower risk of familial tendency. Further investigation is needed to estimate the risk of familial MGUS within each cytogenetic subtype. Disclosures: Kumar: Merck: Consultancy, Honoraria; Millennium: Research Funding; Celgene: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Research Funding.

Abstract Abstract 2059 Introduction: Two randomized trials have demonstrated a benefit in progression free survival (PFS) of 18–20 mofor maintenance treatment with lenalidomide after auto-PBSCT for multiple myeloma (MM). Although results on survival benefit are conflicting and quality of life (QOL) data is lacking, some have begun to recommend maintenance. No study has evaluated patient perceptions of maintenance. We conducted a systematic survey of MM patients (pts) regarding what constitutes a meaningful benefit that would make burdens of maintenance (toxicity and cost) acceptable. Methods: We mailed a brief self-administered survey in 3 waves to 1159 consecutive living pts evaluated at Mayo Clinic. The survey provided background on the standard of care for MM in transplant eligible pts and data on maintenance. Pts were asked to estimate the magnitude of OS benefit that would be acceptable for varying degrees of toxicity and cost. Results: Of the 1159 surveys sent, 886 pts (83.2%) responded, including 150 notifying us of a decision not to participate. 736 pts returned a completed survey (66% raw response rate). (56%) male, 407 (55%) had undergone auto-PBSCT, 467 (63%) had discussed maintenance with a physician, and 9 (1%) pts had received no treatment. 10% of pts had MM for 3–12 mo, 14% for 1–2 yr, 13% for 2–3 yr, 20% for 3–5 yr, 44% for 5 yr or more. Pt age: 4% 18–49 yr, 24% 50–59 yr, 40% 60–69 yr, 27% 70–79 yr, and 6% >80 yrs. The most worrisome potential toxicity was identified as peripheral neuropathy by 27% of pts, cytopenias by 24%, LE DVT 20%, fatigue 15%, nausea 8%, diarrhea/constipation 7%. In response to a question about whether they would choose maintenance if there was a PFS benefit but no improvement in OS, 92% would opt for maintenance if it were known to cause mild toxicity, while 77% would opt for maintenance despite moderate toxicity. Subsequent questions included cost and toxicity considerations and required pts to identify minimum acceptable duration of OS benefit to estimate more precisely a meaningful clinical benefit. If treatment was free, had no toxicity, and the OS benefit was 1 yr or less, 49% would choose maintenance (see Figure). In the same scenario, if toxicities were mild, the proportion of pts who choose maintenance was similar (46%). If pts experienced moderate toxicity, 42% choose maintenance. With rising financial burden (out-of-pocket) and toxicity, the proportion of pts who choose maintenance declined (see Table). For example, if the cost was $25/mo, mild toxicity experienced, and the OS benefit was one year or less, 46% would choose maintenance, while 39% of pts would choose maintenance if it cost $250/month and there was moderate toxicity. If maintenance cost $10,000/mo and was associated with mild or moderate toxicity, 18% and 17% of pts would choose treatment, respectively. Conclusions: For the first time, we have described the broad range of patient perspectives regarding trade-offs in the treatment of MM with maintenance therapy. We found that willingness to be treated with maintenance declined when actual benefits were provided in concrete numeric terms compared with a general statement of PFS benefit. The discrepancy between the 92% of pts choosing to undergo maintenance if free and mild toxicity when there is a PFS benefit but no OS benefit, compared to 49% of pts choosing maintenance if free, mild toxicity, and associated with an OS benefit of 1 yror less; suggests pts have difficulty understanding the concept of PFS. We also found that the magnitude of benefit required to consider maintenance was affected by cost and toxicity. In our experience, pts typically incur a cost of approximately $25/mo and experience mild toxicity. In this study, nearly half (46%) of such pts would opt for maintenance if the OS benefit was 1 year or less while only 33% of pts would opt for maintenance if the OS benefit was 6 months or less. Our data implies that good care in MM requires detailed conversations about each and every patient's priorities and expectations prior to making recommendations for or against such treatments. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 956 Background: Autologous SCT has been an integral part of myeloma therapy since randomized trials demonstrated improved survival for SCT compared to conventional therapy. However, the conventional treatment of MM has changed with the introduction of novel therapies such as IMiDs and there is an increasing trend towards delaying SCT. While trials in the pre-novel agent area have shown equivalent outcomes with early or delayed SCT, it is not clear if this holds true with novel agent induction. Patients and methods: We reviewed the outcome of patients seen at Mayo Clinic between 2001 and 2008, who received initial therapy with thalidomide-dexamethasone (TD) or lenalidomide-dexamethasone (LD) (n=410). All patients in whom a stem cell harvest was attempted (started on growth factor irrespective of collection success; n=292, 71%) were included as a method to identify transplant eligible patients. Patients undergoing SCT within 12 months of diagnosis and in whom the SCT was performed within 2 months of stem cell harvest were considered in the early SCT group vs. delayed SCT for the remaining patients irrespective of whether an SCT was actually done (immediate vs. collect and store approach). Variables were compared between the groups using a chi-square or t-test as appropriate. Survival curves were generated using Kaplan Meier method and compared using log rank test. Results: Among the 292 transplant eligible patients, 125 (43%) received TD and 167 (57%) received LD as initial therapy. An early SCT approach was undertaken in 174 patients 60%, with the remaining 118 in the delayed group, 46 of whom have been transplanted to date. The median estimated follow up for the entire group was 54 months from diagnosis, 52 and 61 months respectively for the early and delayed groups. The median estimated time to SCT was 5.3 months among the early group compared to 39 months in the delayed group COMMENTS/* MERGEFORMAT . 83 (66%) patients receiving TD had an early SCT compared to 91 (55%) patients in the LD group; p =0.04. At baseline, the groups were comparable for age and gender. The median overall survival from diagnosis was 86 months for the early SCT compared to NR for the late SCT; P=0.3. The median OS was similar between the Early and Delayed group in the TD group (86 vs. 64 months respectively) as well as in the LD group (NR for either group; 82% vs. 86% at 4 years respectively). Conclusion: In this group of newly diagnosed patients treated with thalidomide or lenalidomide as initial therapy, an approach of continued initial therapy and delayed transplant at the time of first relapse appears comparable to upfront transplant. This is consistent with the findings of randomized trials in the setting of alkylator based initial therapies. The timing of transplant in the era of novel agents remains the top question on the mind of physicians and patients, and this is the first study to examine this very important question. The rationale governing the decision to go forward with an early SCT or delayed transplant is difficult to ascertain for any particular patient in this retrospective study. These findings should be confirmed in prospective randomized trials. Disclosures: Kumar: celgene: Research Funding; millenium: Research Funding. Gertz:celgene: Honoraria; millenium: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 747 Background: Light chain amyloidosis is a monoclonal plasma cell proliferative disorder characterized by multiorgan deposition of monoclonal light chain derived amyloid fibrils. The diffuse organ infiltration by the amyloid fibrils leads to various AL related clinical features. Therapy of AL has been primarily aimed at elimination or control of the monoclonal plasma cells, thus decreasing the light chain available for amyloid formation. Assessment of response to therapy has been grouped into hematological response demonstrating elimination or reduction of the monoclonal population and organ response demonstrating actual improvement in its structure or function. Given the potentially long delay in observing organ improvement, hematological response has been the surrogate short term marker for long term outcome given the relatively rapid decline seen in the monoclonal protein with effective therapy, as well as studies showing improved long term outcome with a hematological response, especially complete response. However, conventional hematological response criteria give priority to the intact monoclonal protein rather than the light chain, which is the amyloidogenic protein. We hypothesized that a light chain response will correlate better with outcome than changes in the intact monoclonal protein levels. Methods: We identified 348 patients who had undergone stem cell transplant (SCT) for AL from among a large group of patients undergoing different treatments for AL, and in whom serial tests results were available. We identified the lowest value attained following SCT for various hematological response parameters (intact serum M-protein [MP], the difference between involved and uninvolved serum free light chain [FLC-diff], and urine M-protein [UP]) before an alternate therapy was instituted. We first estimated the best cutoff for the degree of change in each parameter that predicted 5-year survival from SCT. Cox proportional hazards model was used for multivariable analysis of factors influencing overall survival (OS). Results: We first examined the relative contribution of the MP and the FLC-diff on the overall survival following transplant. The best cutoff for reduction in FLC-diff to predict OS at 5 years from SCT was 88% if all patients were considered and 90% if only those with a baseline FLC diff > 7.5 mg/dL were considered. The best cutoff for MP reduction was 40% for 5 year survival for all patients and 67% for those with a baseline MP > 1.0 gm/dL. We then looked at the impact of FLC reduction and MP reduction in a multivariable analysis using OS as endpoint. For all patients, FLC reduction, but not MP reduction significantly impacted outcome, and results were similar when considering patients with MP>1.0 gm/dl and FLC-diff > 7.5 mg/dl at baseline. Among those with a baseline FLC-diff >7.5 mg/dL (n=125), the overall survival was 35 mos from SCT for those with less than 90% decrease in FLC-diff (45 pts) compared to not reached for those with at least 90% decrease (80 pts); P < 0.001 (Figure). Conclusions: The current study supports the notion that reductions in the free light chain parameters represent a more useful measure of hematological response that translates into better overall survival and possible better chance at organ improvement. A reduction in the FLC difference of 90% appears to correlate best with prolonged survival. 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. Lacy:celgene: Research Funding.

Abstract Abstract 1802 Poster Board I-828 Background Heterogeneity in multiple myeloma (MM) leads to disparate outcomes with a wide variation in overall survival (OS). Based upon the evidence predominantly gathered from newly diagnosed patients treated with standard chemotherapy and/or transplantation, the current Mayo (mSMART) prognostic model uses a combination of metaphase cytogenetics, fluorescence in-situ hybridization (FISH) and plasma cell labeling index (PCLI) for risk-stratification at diagnosis of MM. The objective of our study was to evaluate the significance of this stratification model in the era of novel therapies, and to assess the independent prognostic value of each of the components in the model. Methods Data were abstracted from a cohort of 1556 consecutive patients with MM who presented to our institution between January 1999 and March 2009 within ninety days of diagnosis of MM A total of three hundred and eighty six patients had been evaluated with conventional cytogenetics near diagnosis in addition to interphase FISH. Out of this cohort, three hundred and sixty six patients had availability of all the three tests, including the slide-based PCLI. High-risk MM was defined as presence of any one or more of the following: cytogenetics: hypodiploidy, monosomy of chromosome 13 or deletion 13q ; FISH: deletion of p53 (locus 17p13) or immunoglobulin heavy chain (IgH) translocations, t(4;14) (p16.3;q32) or t(14;16)(q32;q23); PCLI ≥3%. Survival estimates were created using the Kaplan-Meier method and compared by log-rank tests. The impact of each of the three tests was assessed by a multivariate (MV) analysis using Cox proportional hazards model. Results The median OS of the cohort of 366 patients was 65 months from presentation. One hundred and twelve (31%) patients were deemed high risk by any one or more of the three tests: Metaphase cytogenetics, FISH or PCLI (current mSMART definition of high-risk MM). The median OS of high risk patients was 52 months versus 71 months for standard-risk (P=0.007). We then studied the prognostic value of the three tests separately. Patients classified as high risk by FISH had a median OS of 35 months versus 65 months for the standard risk, HR= 2.3, P<0.001. Similarly, cytogenetics alone was also able to classify patients into high and standard risk with a comparable HR of 2.1 (P=0.008, median survival 37 vs. 64 months). In contrast, PCLI did not have a significant prognostic value (HR =1.41, P=0.32). This was confirmed on multivariate analysis in a model that included all 3 tests. FISH (HR=2.36, P=0.001) and cytogenetics (HR=1.99; P=0.017) emerged as independent determinants of prognosis in the multivariable analysis, while PCLI (HR=1.03, P=0.93) did not provide additional prognostic value. We then examined whether the prognostic value of FISH contributed additionally in patients classified into high and standard risk by conventional cytogenetics, and vice versa. Those classified as high risk by cytogenetics (n=44, 11 %), were further categorized into 2 groups by additional prognostic information obtained by FISH (median survival 18 vs. 52 months; P=0.005). Similarly, those classified as standard risk by cytogenetics (n=342, 89 %), were further categorized into 2 groups (median survival 52 vs. 71 months; P=0.017) by additional FISH-based stratification. Similarly, high-risk patients defined by FISH (n=65, 17 %) were further classified into 2 groups with significant difference in median OS (18 vs. 52 months, P=0.004), based on the presence or absence of high-risk features on cytogenetics. In contrast, no additional prognostic information was gained by cytogenetics in patients who were stratified as standard risk by FISH alone (n=321, 83%). Conclusion Our study validates high risk features defined by FISH and conventional cytogenetics in the mSMART risk stratification model among patients treated after the introduction of novel therapies. Either test identifies a high risk cohort with a hazard ratio of approximately 2 (median survival ∼37 versus ∼65 months). In patients known to have high risk disease by one of the two tests, knowledge of the other appears to add additional prognostic value. Disclosures Fonseca: Amgen, BMS, Celgene, Otsuka, Genzyme and Medtronic: Consultancy. Gertz:celgene, millennium: Honoraria. Dispenzieri:celgene: Research Funding. Kumar:celgene, genzyme, millennium, novartis, bayer: Research Funding; genzyme: Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 946 Background: The emerging therapies directed at the plasma cell clone have dramatically increased overall survival (OS) for both myeloma and amyloidosis patient populations. As more treatment trials are done in patients (pts) with AL, benchmarks for outcomes among previously treated AL pts are required, especially for those pts who are not candidates for high-dose chemotherapy with peripheral blood stem cell transplantation (ASCT). Inadequate information is available about the number of non-transplant pts who go on to receive second line treatment for AL amyloidosis. Methods: To ascertain the outcomes of pts who did not receive ASCT as primary therapy but who required a second line of therapy, we reviewed the experience of pts seen at Mayo Rochester between 1990 and 2010 according to an IRB approved retrospective review protocol. 1828 pts had their first Mayo visit for AL during this time period. Pts were excluded from this study for the following reasons: 571 had upfront transplant; 907 pts had received only one line of treatment for their amyloid; 91 had longstanding other associated malignancy [Waldenstrom's macroglobulinemia (8), lymphoma (15), CLL (6), multiple myeloma (62)]; and 93 had inadequate follow-up information. One-hundred and sixty-six pts received 2 or more lines of therapy for their AL amyloid and are the subject of these analyses. Statistical analyses were done using JMP statistical software (SAS, Carey, NC). Results: Of the 166 pts, the median age was 64 years (range 34, 84). 49% were male. Baseline organ involvement was as follows: cardiac 84/166 (50%); renal 118/166 (71); liver 23/166 (13.8%); peripheral nerves 19/166 (11.4%); and gastrointestinal 14/166(8.4%). Thirty-one percent (52/16) had both cardiac and renal involvement. Only 73 pts had cardiac biomarkers (NT pro BNP and Troponin T) done at baseline. Of these pts, 26% were stage 1, 49.3% were stage 2, and 24.6% were stage 3 according to original Mayo cardiac biomarker staging system. By inclusion criteria definition, all 166 pts received 1st and 2nd line therapies; 53 (32%) pts received 3rd line of treatment; 20 (12%) received 4th line of treatment; and 10 (6%) received 5th line of treatment. For first line therapy, the most common drugs given either singly or in combination were corticosteroid (147/166; 88.5 %), alkylator (99/166; 59.6%), IMID (34/166; 20.4 %), and bortezomib (19/166; 11.4%). The median time from diagnosis to 2nd line therapy was 10.3 months. Second line regimens received included: corticosteroid, 108/166 (65.1%); alkylator, 76/166 (45.8 %); IMID, 46/166 (27.7%); and bortezomib, 46/166 (27.8%). The median time from diagnosis to 3rd line therapy was 19.8 months. For the 53 pts who received 3rd line treatment, regimens included: corticosteroid, 41/53 (77.3%); IMIDs, 17/53 (32.1%); alkylator, 17/53 (32.1%); bortezomib, 12/53 (22.6%). The median time from diagnosis to 4th line therapy was 31.8 months. For the 20 pts receiving 4th line treatment, regimens included: corticosteroids, 15/20(75%); alkylator, 12/20 (60%), bortezomib, 7/20 (35%); and IMIDs, 4/20(20%). Eighty-three pts have died. The 1 year mortality of our study population was only 8%. The median follow-up of surviving pts was 47.6 months. Figure 1 demonstrates Kaplan-Meier estimates of overall survival (OS) from initiation of each successive therapy. The median OS from initiation of 1st, 2nd, and 3rd lines of treatment were 65, 49.5 and 36.7 months respectively. The median OS after the 4th line of treatment was not reached. The 4 year OS rates from initiation of 1st, 2nd, 3rd and 4th lines of therapy were 58%, 50.8 %, 50 % and 53.4% respectively. Conclusion: Outcomes among relapsed or refractory AL pts are better than what one might expect. Multiple publications have demonstrated that the 1 year mortality of newly diagnosed AL is in the vicinity of 40%. Thereafter, the rate at which pts die dramatically decreases. Our study provides explicit data characterizing the fate of pts unfortunate enough to require additional therapy but fortunate enough to survive past the exceedingly high risk period of death that occurs within 6–12 months of diagnosis. These data provide useful information for benchmarking future trials for treatments of AL amyloidosis. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: There has been major improvement in the survival of patients diagnosed with multiple myeloma (MM) over the past two decades. Such improvement has been attributed to the broader use of hematopoietic progenitor cell transplantation and novel drugs that prolong initial remission and more successfully treat relapsed disease. Early mortality (EM), here defined as death in the first year after diagnosis, is uncommon in modern MM trials. The magnitude of EM in unselected patients with MM and its impact on overall outcomes in this disease is unknown Methods: We analyzed EM in MM utilizing data from the Surveillance Epidemiology and End Result Program (SEER-13). Patients diagnosed with MM as first malignant neoplasm between 1993 and 2010 (follow up until end of 2011) were included. Cases reported from death certificate or autopsy only were excluded, along with patients recorded as alive but with no survival time (<1% of total). Relative EM rates (1 – relative survival) used data from the US population in 2000 as reference. We described EM for different population groups, changes over time and performed multivariate analysis (binary logistic regression) to assess risk factors for EM in MM. To assess the impact of factors other than reduction in EM in the increased survival of MM, we performed a landmark survival analysis including only those patients who survived at least 1 year after diagnosis. Results: There were 30,324 patients in the analysis, 11,439 diagnosed at age < 65 and 18,885 at age ≥ 65. Absolute EM was 17.6% and 35.3% while relative EMwas 16.9% and 31.7% for the younger and the older groups respectively. There was decline of relative EM rates that occurred in both age groups but only became evident among older patients after 2005 (Figure 1). In multivariate analysis, factors associated with increased risk of EM were male sex, age ≥65 years , diagnosis in 1993-2001, presence of primary plasma cell leukemia, low household income and residence in the coverage area of certain SEER registries (Table 1). Landmark analysis of 1-year survivors demonstrated increased survival from 1993-2001 to 2002-2010 for patients < 65 (median 58 vs. 85 months, P<0.001) and for patients ≥ 65 (median 38 vs. 48 months, P<0.001, Figure 2). Conclusions: Reduction in EM partially explains population improvements in MM overall survival. EM remains high in MM and a major barrier for continued improvement in survival outcomes. Table 1 Factor Reference OR 95% C.I. P Female sex Male 0.90 0.85-0.95 <0.001 Year of diagnosis 1993-2001 2002-2010 1.16 1.10-1.22 <0.001 Plasma Cell Leukemia Multiple Myeloma 5.62 4.17-7.58 <0.001 Age ≥65 years < 65 years 2.56 2.42-2.72 <0.001 Race-ethnicity <0.001 NHB NHW 0.97 0.90-1.04 0.39 Hispanic NHW 1.04 0.95-1.14 0.41 AIAN NHW 0.90 0.63-1.28 0.56 API NHW 0.84 0.75-0.94 0.004 Median household income# 0.91 0.87-0.95 <0.001 SEER registry <0.001 Alaska Los Angeles 1.37 0.62-3.02 0.43 Atlanta Los Angeles 1.003 0.89-1.14 0.96 Connecticut Los Angeles 0.83 0.75-0.93 0.002 Detroit Los Angeles 1.06 0.96-1.16 0.23 Hawaii Los Angeles 1.21 1.01-1.45 0.04 Iowa Los Angeles 0.89 0.80-0.99 0.03 New Mexico Los Angeles 0.88 0.77-1.01 0.07 Rural Georgia Los Angeles 1.10 0.76-1.58 0.63 San Francisco-Oakland Los Angeles 0.99 0.86-1.11 0.87 San Jose-Monterey Los Angeles 1.05 0.87-1.12 0.51 Seattle-Puget Sound Los Angeles 0.91 0.83-1.01 0.08 Utah Los Angeles 1.13 0.98-1.29 0.08 NHB= non-Hispanic Blacks;, NHW= non-Hispanic Whites; AIAN= American Indian, Alaska Natives; API= Asian and Pacific Islanders; #Per US$ 10,000 Figure 1 Figure 1. Figure 2 Figure 2. Disclosures No relevant conflicts of interest to declare.

Abstract Abstract 194 Background: Immunomodulatory drugs (IMiDs) are key components of treatment for hematologic malignancies, especially multiple myeloma (MM). Recently, we demonstrated that CRBN expression is the major mediator of IMiD action operating at least in part via interferon regulatory factor 4 (IRF4), however the clinical significance of this finding remains unclear. Methods: To better understand clinical impact, we retrospectively reviewed 148 MM patients whose tumor cells were tested for CRBN expression by Gene Expression Profiling (GEP) prior to treatment with an IMiD containing therapy. Results: GEP studies show no significant differences in CRBN expression between MGUS, smoldering MM (SMM), untreated symptomatic MM and normal plasma cells. However, differences were observed between MM cell lines of varying drug sensitivity to IMiDs and between other B-cell Neoplasia (eg low grade lymphoma has higher levels). Within the genetic subtypes of MM, levels were significantly higher for hyperdiploid patients (median 1.26) as opposed to significantly lower levels for TC class D2 (median 0.76) and average for the 4p16 (median 0.97). We next screened the University of Arkansas Medical School (UAMS) GEP database of MM patients treated with combination therapies and did not find significant correlation between CRBN expression and survival in this multi-agent regimen. We then focused on patients that received only single agent IMiD therapy with low dose dexamethasone. Review of the twelve lowest expressing patients demonstrated a lack of response to IMiDs in any patient. Finally we analyzed 53 relapsed or relapsed/refractory patients treated homogeneously in a study with pomalidomide 2–4mg daily and weekly dexamethasone 40mg. CRBN levels were assessed prior to therapy initiation. Response rates varied significantly based on gene expression level. The percentage of patients that demonstrated at least a partial response was 0% for CRBN <0.81, 19% for CRBN expression of 0.81–0.90, and 33% for CBN expression >0.9. Significant differences in PFS (3.0 months vs. 8.9 months, p = 0.0006) and in OS (9.1 months vs. 27.2 months, p = 0.01) were observed when the lowest quartile of CRBN expression was compared to the top three quartiles. Values used for the cut offs are as follows: (25%: 0.889687; 50%: 1.026542, 75%: 1.211133). While this study demonstrates a positive correlation between CRBN expression and response to pomalidomide and dexamethasone, an important caveat with respect to PFS and OS is that CRBN mRNA level is primarily a reflection of the number of copies of CRBN. Since focal deletions are uncommon, this mostly reflects chromosome 3p copy number. Since trisomy 3 is common in hyperdiploid, good prognosis disease, CRBN not only is required for IMiD function but higher levels also serve as a surrogate for low risk disease. Optimal gene expression cut offs for survival were determined using the Contal and O'Quigley method. The optimal cut point for PFS was 1.18443 and for OS was 1.17816. Conclusion: In summary, this study demonstrates, for the first time, a clinical correlation between CRBN expression and response to IMiD and dexamethasone therapy. CRBN expression is also predictive of survival outcomes and when quantified prior to therapy could potentially be utilized as a predictive biomarker for response to an IMiD based treatment. Disclosures: Stewart: Celgene: Consultancy, Honoraria.

Abstract Abstract 3928 Background: Accumulating data support the critical role of PI3K/Akt in CLL B cell receptor (BCR) mediated signal transduction, cell proliferation and survival. In addition recent preclinical and clinical studies indicate that specific PI3K blockade results in robust preclinical and clinical efficacy in CLL. In our model system of CLL B cell-stromal cultures which feature their interaction, platelet derived growth factor (PDGF) present in CLL culture medium drives VEGF production through PI3K/Akt activation in stromal cells (Blood. 2010. 116:2984). Indeed Akt was found to be activated in leukemic cells during the CLL-stroma interaction (Leuk Res. 2008. 32:1565). Therefore, we hypothesized that Akt inhibition should promote CLL B cell apoptosis and abrogate BCR mediated cytokine production. MK2206 is an orally bioavailable highly specific allosteric Akt inhibitor. It has been tested in patients with refractory solid tumors and was demonstrated to be safely administered in a phase I trial. Therefore the goal of this study was to test the preclinical efficacy of MK2206 on both the survival and the BCR mediated cytokine production of CLL leukemic B cells. Methods: Peripheral blood mononuclear cells isolated from CLL patients (n=37) were treated with escalating concentrations of MK2206 (1–16 μM) for 24 hours, 48 hours or 72 hours. The levels of leukemic B cell viability were tested using an (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay. The potential impact (antagonistic/additive/synergistic) of Bendamustine in combination with MK2206 was also tested by using the MTT assay. We used the Calcusyn system to calculate the effect of drug interactions. The combination index (CI) as calculated by the program usually indicates synergy when ≤ 0.8 and indicates additive outcomes when between 0.8–1.2. A CI >1.2 indicates antagonism. Downstream signals of Akt activation in CLL B cells were evaluated by testing their expression of Mcl-1, 4EBP1 and p70S6K using immunoblot. The impact of Akt inhibition by MK2206 on cytokine production in response to B-cell receptor ligation with anti-IgM was also tested using a multiplex cytokine analysis (Invitrogen) in a time-course experiment. Results: MK2206 treatment induced concentration- and time-dependent apoptosis in CLL leukemic cells. At 72 hours, the IC50 of MK2206 in the experiments using CLL leukemic cells in vitro is ∼8 mM. MK2206 incubation at 1 or 5 mM cultured with CLL B cells over a 48-hour period abolished of Akt and p70S6K phosphorylation while native PARP was cleaved into the 85 kD polypeptide fragment. However, the expression level of the upstream signal molecule, PI3K, was not changed. Among the CLL patients tested (n = 37), we did not find any difference in sensitivity to MK2206 induced apoptosis based on critical prognostic factors of CD38, ZAP-70, IGHV and del(17p) status. Importantly, we detected synergistic or additive activity between MK2206 and Bendamustine in 11 tested CLL samples when these combinations were used to treat CLL cells in vitro for 72hrs. Thus the median CI value for this group of patients was 0.8 (0.1 – 1.1). Six were found to have CI ≤ 0.8 and five fell within the additive CI values (0.8 – 1.2). Production of immune or chemotactic cytokines (e.g. CCL3, CCL4, MCP-1, IL-1Ra, IL-8 and IL-2R) at 24 hour incubation increased significantly above baseline when CLL cells were stimulated anti-IgM. Akt inhibition with MK2206 selectively abrogated upregulation of CCL3, CCL4, MCP-1 and IL-2R production, but not for IL-8 or IL-1Ra secretion. MK2206 also abolished BCR mediated Akt activation and decreased Erk activation. Conclusion: MK2206, a robust and selective Akt inhibitor, induced significant in vitro apoptosis of CLL B-cells in vitro. Preclinical evidence of a synergistic effect between MK2206 and Bendamustine was also observed independent of prognostic risk. MK2206 abolished BCR mediated Akt activation and selectively abrogates BCR mediated production of cytokines that may promote apoptotic resistance. These findings support the use of MK2206 in treating CLL and indeed we have initiated a phase I/II trial of MK2206 in combination with Bendamustine and Rituximab for relapsed CLL patients(N1087, October 2011). Acknowledgments: This study was funded by the NCI-K23, NCCTG and CLL Global Foundation. Disclosures: Shanafelt: Cephalon: Research Funding; Genentech: Research Funding. Kumar:Genzyme: Research Funding; Novartis: Research Funding; Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Honoraria. Kay:Celgene: Research Funding.

Abstract Abstract 1988 Background With the utilization of novel agent-based combination therapies and autologous stem-cell transplantation (ASCT) in multiple myeloma (MM), the rigorous response category of stringent complete remission (sCR) in the international uniform response criteria is increasingly becoming attainable. In addition to the standard criteria for complete remission (CR), sCR requires normalization of the free light chain ratio and disappearance of clonal cells as determined by the marrow immunofluorescence or immunohistochemistry. We have previously validated the new response category of sCR created in by the International Myeloma Working Group and demonstrated that sCR represents a deeper level of response, translating into a superior OS. Herein we report the survival outcomes of patients attaining sCR or standard CR, from a 2-year landmark after ASCT in a cohort of patients with extended follow-up. Additionally, we report the outcome of patients who remained in sCR for at least 6 months (sustained-sCR) after ASCT. Patients and Methods Maximal response rates of four hundred and forty-five consecutive patients who underwent ASCT within 12 months of diagnosis of MM were determined. The population achieving varying degrees of complete remission (n=237) is the focus of this study. We performed a landmark analysis 2 years after ASCT to ensure that all the patients attaining at least CR had sufficient time to reach the response levels being studied. Patients were categorized as having sustained sCR (sus-sCR) if the duration of sCR was at least 6 months. Overall survival (OS) was estimated by the Kaplan Meier method and the survival curves were compared by log-rank test. Results The median follow-up of the entire cohort was seventy-seven months (95% CI: 73–82 months). The sCR rate after ASCT was 24% (n=109). Median time to progression (TTP) of patients attaining sCR was 50 months from ASCT, and median overall survival (OS) is not reached, in contrast to those attaining standard CR (n=37, TTP=20 months, OS=81 months) or near CR/nCR (n=91; TTP= 19 months, OS=60 months, p<0.0001 for both TTP and OS). OS of patients surviving at least 2 years from ASCT (Figure 1a) continued to remain superior for those attaining sCR (n=105, median: not reached) versus 70 months for the CR group (n=32; p=0.004). Among patients achieving sCR (n=109), OS of patients with sus-sCR (n= 75) at 6 months from ASCT is not reached (5-year OS=91%, 7-year OS=86%) versus median OS of 66 months (5-year OS=49%, 7-year OS=37%; p<0.0001) for those who had non-sustained-sCR (n=34) after ASCT (Figure 1b). Conclusion In our landmark analysis of patients with MM who survived at least 2 years from ASCT, those attaining sCR have a markedly superior outcome compared to those attaining standard CR. However, among patients attaining sCR, those with sustained sCR of 6 months or greater had the best outcome. Myeloma trials reporting response rates should identify patients achieving sCR and CR separately owing to markedly disparate outcomes of the two categories. Disclosures: No relevant conflicts of interest to declare.