Citations

Abstract Abstract 3949 Acute kidney injury (AKI) is a common but serious sequela of multiple myeloma. Recently, the International Myeloma Working Group (IMWG) introduced a new renal response criteria with complete (CRenal), partial (PRenal) and minimal (MRenal) responses. This study compares the IMWG criteria with other models to determine their correlation with overall survival (OS). Patients with multiple myeloma and AKI were identified from centers around the world. OS was calculated from the day of AKI. Renal function was assessed by estimated glomerular filtration rate (eGFR) via MDRD method. Hematologic response was the best achieved as assessed by International Uniform Response Criteria for Multiple Myeloma. Only patients with peak serum creatinine (Scr) ≥ 2.0 mg/dl were included. Separate analyses were performed on the newly diagnosed (ND) versus previously treated (PT) patients. A total of 158 patients were collected from centers in United States, United Kingdom, France and Austria. Fourteen patients were excluded for having peak Scr < 2.0 mg/dl and one for repeated episodes of AKI. Median age of the 143 patients was 64 (34 – 87) years, 58.7% were male and 115 were newly diagnosed. Median Scr was 5.1 (2.0 to 18.6) mg/dl and median eGFR was 10.6 (2.8 – 36.5) ml/min/1.72 m2. Dialysis was required in 49.3%, and 72.9% were dialysis independent at the end of the study. By IMWG criteria, median OS ranged between 6.0 months (m) in PT patients with no renal response (NRenal) to 23.7m in patients with CRenal, p = 0.34 (Table 1). In ND patients, OS was 31.4m in NRenal vs 73.8m in CRenal (p = 0.08). However, OS was similar between PRenal and CRenal, p = 0.70 (Figure 1). If only patients with a hematologic PR or better were analyzed, the OS range was 6.0m in NRenal to 23.7m in CRenal in PT patients (p = 0.85) and 36.6m in NRenal to 73.8m in CRenal in ND patients, p = 0.73.Table 1.Previously TreatedNMedian SurvivalNMedian Survival (>PR) CRenal323.7 m323.7 m PRenal413.1 m312.8 m MRenal512.0 m119.2 m NRenal166.0 m56.0 m p-value0.340.85Newly Diagnosed CRenal2273.8 m2273.8 m PRenal27Not Reached23Not Reached MRenal2265.6 m1965.6 m NRenal4331.4 m2136.6 m p-value0.080.73Figure 1.Overall survival (OS) of 115 patients evaluated by the IMWG renal response criteria. OS was not significantly different by Log-Rank test between patients with CRenal and NRenal, p = 0.08.Figure 1. Overall survival (OS) of 115 patients evaluated by the IMWG renal response criteria. OS was not significantly different by Log-Rank test between patients with CRenal and NRenal, p = 0.08. The best model tested was one that defined renal response (RR) as regaining or maintaining dialysis independence and no response (NR) as dialysis dependence. RR was associated with a superior survival for both PT patients (13.5 m vs 6.0m (NR), p = 0.03) and ND patients (73.8m vs 20.1m (NR), p < 0.001). RR increased with the depth of hematologic response, p = 0.04. RR occurred in 75% of the PT patients with hematologic PR or better and 66.7% in those with less than PR, p = 0.64. In ND patients, RR occurred in 85.7% of those with PR or better and 54.6% of those with PR or less, p = 0.003. This may explain the differences in OS when hematologic response was considered. In PT patients with hematologic PR or better, renal response did not improve OS (21m vs 6m, p = 0.28) but it remained beneficial in the ND patients (73.8m vs 35.1m, p = 0.04, Figure 2). Renal response was not significantly associated with OS for any patient with hematologic response that was VGPR or better. In a multivariate analysis, RR (p = 0.001), ND (p <0.001) and PR or better hematologic response (p = 0.046) were associated with OS.Figure 2.In a separate model, 83 newly diagnosed patients with hematologic response of PR or better were evaluated. Patients who were dialysis independent achieved a renal response (RR) and those who remained on dialysis had no response (NR). Patients with RR had a superior overall survival than patients with NR. Renal response was independent of a hematologic response of PR or better.Figure 2. In a separate model, 83 newly diagnosed patients with hematologic response of PR or better were evaluated. Patients who were dialysis independent achieved a renal response (RR) and those who remained on dialysis had no response (NR). Patients with RR had a superior overall survival than patients with NR. Renal response was independent of a hematologic response of PR or better. The results of our study suggest renal response is important to OS but the depth of response was not as important. Renal response was most important when the hematologic response was less than a VGPR. This supports renal response as part of the overall response assessment in multiple myeloma patients. Based on our results, reducing the number of response categories and simplifying the current consensus criteria seems justified. Median survival of the 143 patients evaluated by the IMWG renal response criteria. Overall survival was calculated by Kaplan Meier method. Differences in survival were evaluated by Log-Rank test. Disclosures: Ludwig: Mundipharma, Janssen-Cilag: Research Funding, Speakers Bureau. Hutchison:The Binding Site: Honoraria.

Abstract Introduction: Localized immunoglobulin light chain amyloidosis (LAL) is a rare disease. Systematic data regarding its presentation, management and patient outcomes are limited to small case series. Our objective was to systematically describe the Mayo clinic experience of patients with LAL. Methods: We retrospectively reviewed clinical records of 403 patients with biopsy proven localized amyloidosis seen at the Mayo Clinic between 1969-2014. Median follow-up for survival and progression were 72 months and 39 months, respectively Results: OF 5551 patients with light chain amyloidosis seen at the Mayo clinic during the study period, 403 (7%) had LAL. Median age at diagnosis was 60 years (range, 13-93) and 51% of them were male. Sites involved included: urothelial (bladder, ureter, renal pelvis), 75 (19%), larynx, 51 (13%), lung parenchyma, 42 (11%), skin, 44 (11%), synovial tissue 36 (9%), tracheobronchial, 31 (8%), gastrointestinal tract, 30 (8%), seminal vesicles, 22 (6%), eyes, 23 (6%), pharynx 22 (6%) and other 24 (6%). Typing was performed in 178 (45%) cases. A monoclonal protein was detected in 23 of 351 (7%) evaluated cases, 5 of which had different light restriction from that of LAL. Thirty one (8%) patients had a co-existent autoimmune disease. No patients progressed to systemic AL. Of 403, 109 (27%) were observed or received supportive care only and 241 (60%) underwent local removal of the amyloid deposits. Sixty-four (16%) patients required repeated interventions (median 1, range 1-4, upper decile requiring 4 interventions) for progressive disease. The most common sites requiring repeated interventions were: urothelial (33%), laryngeal (19%) and tracheobronchial (8%). Ten year overall survival (OS) and progression free survival were 79% and 61%, respectively and there was no difference according to site of involvement. Of the 70 patients that died during the follow-up period, cause of death was known for 29 and death was attributed to LAL in only 2 cases. Conclusions: In the largest series of patients with LAL reported so far we demonstrated that LAL has an excellent prognosis but can sometimes be associated with significant morbidity. Although our study was limited by incomplete typing in 55% of cases, it appears that true LAL does not "progress" to systemic amyloidosis. However, systemic amyloidosis can frequently involve organs typical involved only in LAL;, therefore a complete work-up for systemic disease should be performed in all patients with LAL. Treatment usually involves local excision for symptom palliation. In 16% of cases, repeated interventions for relapse/progression were required and as a result, follow-up is recommended, especially for cases involving the urothelial and upper respiratory tract. Disclosures Kumar: Skyline, Noxxon: Honoraria; Celgene, Millennium, Onyx, Novartis, Janssen, Sanofi: Research Funding; Celgene, Millennium, Onyx, Janssen, Noxxon, Sanofi, BMS, Skyline: Consultancy.

Abstract Background Waldenström macroglobulinemia (WM) is a rare, indolent immunoglobulin M- associated lymphoplasmacytic lymphoma characterized by the alternation in the MYD88 locus in 90-95% of the cases. MYD88L265P is the most common alteration in WM patients and is considered a key molecular signature with a pathophysiological role in WM. Because of extremely low prevalence of WM with MYD88 wild type (WT) genotype there is a paucity of clinical and outcome data in this unique patient population. A recent study (Treon et al, Blood May, 2014), in an analysis based on the patients' MYD88 status, reported on the clinical features including older age at presentation and an unexpectedly higher mortality (38%) in the MYD88WTcohort compared to MYD88L265P patients (mortality 6%, P < .0001). However, the sample size of the MYD88WT WM cohort was small (n=15), with a few events during the short follow-up (median 4.84 years). Herein, we report on larger cohort of WM patients with this rare genotype. Methods This study included patients evaluated at Mayo Clinic, Rochester in whom the diagnosis of WM was established based on their clinicopathologic features and the MYD88 mutation status was determined through AS-PCR (assay sensitivity 1% mutant allele) performed on archived bone marrow samples obtained between 2007-2014. Patients with MYD88WT status were the focus of this study. Clinical data were collected from the patients' medical records. The Kaplan-Meir method was utilized for the survival analysis calculated from the time of diagnosis of WM. Outcomes of MYD88WT patients were compared with those harboring the MYD88L265Pmutation. Results Our cohort of 171 patients with an established diagnosis of WM and known MYD88 mutation status was found to be enriched for MYD88WT (n=40) patients. All patients required therapy. At diagnosis, the median age of the patients with MYD88 WT was 63 years (range 37.5-83.5 years; comparable to that of the MYD88L265P cohort, median 65 years, range: 32-92 years, p=0.16). Familial WM was identified in 10% of patients. Sixty four percent of patients presented with constitutional symptoms at diagnosis. These symptoms included fatigue (45%), weight loss (17%), night sweats (8%) dizziness (10%), dyspnea (23%), bleeding (10%), headache (10%) and hyper viscosity syndrome (5%). Splenomegaly and lymphadenopathy was observed in 20% and 27% of patients, respectively. Thirteen percent of patients had concomitant AL amyloidosis. Additional baseline characteristics are reported in Table 1. Transformation to a higher grade lymphoma was noted in 9 (23%) of patients, four of whom had received a purine analog and /or chlorambucil previously. The estimated median follow of MYD88WT patients was 8.1years (95% CI: 6.4-8.9) and their median overall survival (OS) was 8.5 years (95% CI: 6.4-29.4). No OS difference was evident between this cohort and the remainder of the patients with the MYD88L265Pmutation (n=131, median OS 11.7 years, 95% CI: 10-18, p=0.7; median follow-up 7.7 years 95% CI: 6.4-9.1, Figure 1). Conclusion In this relatively large cohort of WM MYD88WT patients with a prolonged follow-up, the MYD88mutation status was not found to be a determinant of patients' outcomes. Our findings contradict the results of a seminal previous study and require external validation, preferably through prospective studies. Disclosures Kapoor: Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Ansell:BMS, Seattle Genetics, Merck, Celldex and Affimed: Research Funding. Kumar:Sanofi: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Glycomimetics: Consultancy; Onyx: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy; Millennium: Consultancy, Research Funding; AbbVie: Research Funding; Kesios: Consultancy.

Abstract Abstract 3989 Background: Treatment patterns of multiple myeloma (MM) vary across the globe, mostly dictated by the availability and patient access to different drug therapies. The outcomes of patients with MM, especially relapsed myeloma can be significantly affected by the availability of newer treatments, as well as potential biological differences related to ethnicity. We have previously shown that the outcome of patients relapsing after therapy with bortezomib (Bz) and one or more of the IMiDs remain poor with the currently available treatments and represent a difficult group of patients to treat. We undertook the current analysis on a set of patients from United States, several European countries and South Korea. Methods: We designed a multicenter, retrospective study that enrolled 294 patients with relapsed MM, from 14 sites (122 from Europe, 107 from US, and 65 from Korea). Patients were refractory to Bz, defined as no response to prior Bz-containing regimen or disease progression within 60 days of a Bz-containing regimen. Patients were also relapsed, refractory, intolerant, and/or ineligible, to treatment with an IMiD (thalidomide or lenalidomide). The date patients satisfied the above entry criteria was defined as time zero (T0). Clinical and laboratory data from diagnosis and individual relapses were collected along with details of all MM drug therapies before and after T0. Responses were assessed by IMWG or EBMT criteria. The goal of the study was to compare the characteristics of patients who satisfy the above inclusion criteria, the therapies employed prior to and after T0 and clinical outcome among these patients from different parts of the world. Results: The mean (median, range) time to reaching T0 from diagnosis was 4.5 (4.0, 12.8), 4.2 (3.2, 18.6), and 3.2 (2.8, 9.6) years from diagnosis for patients from US, Europe and Korea, respectively, P=0.021. The mean (median, range) number of therapies for the three groups were 8 (8, 13), 4 (4, 10), 5 (4, 7), respectively; P<0.001. The response rates (>=PR) to the initial therapy at diagnosis were 56%, 77% and 49% respectively for the US, European and Korean cohorts. Overall 220 patients had at least one therapy after T0, and 114 (52%) had a novel agent (Bz, len or thal) containing regimen as their first treatment after T0. Patients in US were more likely to receive additional therapies after the first post-T0 therapy; 62%, 32%, and 12% of patients from US, Europe and Korea, respectively, began a second post-T0 regimen within 2 years following time zero. The median number of therapies post T0 was 2, 1, and 1 for patients in US, Europe and Korea respectively. The response rates to the first regimen after T0 were 15%, 33% and 19% for the US, European and Korean cohorts, and were similar between those receiving a regimen with one of the novel drugs compared to rest. Patients younger than 60 years and those with prior transplants were more likely to respond to post T0 regimens. The median time to progression or death from T0was similar for the three patient cohorts, 5 months (Figure 1A). The median overall survival (95% CI) from T0 was 13 months (10, 16), 7 (5,9) and 8 (4,9) respectively for the US, European and Korean cohorts (Figure 1B). Conventional prognostic factors, especially the ISS stage was predictive of OS post T0. Additionally, presence of extramedullary disease was associated with a shorter overall survival. Conclusion: The results of the current study demonstrate significant differences between different parts of the world in terms of the treatment patterns both in the setting of initial therapy as well as treatment of relapsed disease. Patients in the US were more likely to receive multiple regimens both before and after T0. This is likely a reflection of increasing numbers of new drugs that have gone into clinical trials and thus enhancing options. The study further highlights the poor outcome of patients who have relapsed after the new drugs, irrespective of the geographical location. Disclosures: Kumar: Merck: Consultancy, Honoraria; Genzyme: Consultancy; Celgene: Consultancy. Richardson:Millennium: ; Celgene: ; Johnson & Johnson: ; Novartis: ; Bristol Myers Squibb:. Moreau:Millennium Pharmaceuticals, Inc.: Advisory board, Honoraria; Janssen: Advisory board, Honoraria. Sonneveld:Millennium Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Membership on an entity's Board of Directors or advisory committees, Research Funding. Siegel:Merck: Honoraria; Millenium: Honoraria, Research Funding, Speakers Bureau. San Miguel:Janssen-Cilag: Honoraria; Celgene: Honoraria. Palumbo:celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees. Durie:Celgene: Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 1756 Background: We hypothesized that surrogate markers of host immune response to clonal myeloproliferation predict survival in myeloid malignancies. Because of immediate applicability to current practice, we chose plasma immunoglobulin free light chain (FLC) concentration (B-cell activation marker) as the biomarker of interest. Patients and Methods: Two independent cohorts of patients with primary myelofibrosis (PMF) or myelodysplastic syndromes (MDS) were studied. Both groups were fully annotated for karyotype. Kappa (κ) and lambda (λ) FLC were measured by a quantitative nephelometric assay. Patients with monoclonal FLC were excluded. Results: Above upper normal-limit values for κ or λ FLC was documented in 33% of 240 study patients with PMF and 46% of 74 patients with MDS. Multivariable analysis revealed significant associations between increased FLC and elevated creatinine, as well as advanced age in PMF (p=0.0004) and hemoglobin <10 g/dL in MDS (p=0.005). Increased FLC predicted shortened survival in both PMF and MDS, independent of age, creatinine, and other conventional risk factors. Receiver-operating characteristic analysis-based cutoff levels for κ plus λ total FLC delineated risk groups with highly significant differences in overall survival (Figure); International Prognostic Scoring System-adjusted HR (95% CI) in PMF was 1.9 (1.3-2.7) and in MDS 6.3 (2.7-16.6). No correlations were seen with leukemia-free survival, karyotype or JAK2, MPL or IDH mutations. Conclusions: Elevated plasma FLC concentration predicts inferior survival in both PMF and MDS. Its lack of correlation with leukemia-free survival and tumor-specific genetic markers suggests a primarily host-driven biological phenomenon that might be applicable to other malignant and non-malignant conditions. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: Lenalidomide with dexamethasone (Rd) is a standard of care for patients with previously untreated multiple myeloma. SWOG S0777, a randomized phase III trial, has compared Rd with bortezomib, lenalidomide and dexamethasone (VRd). The primary end point is progression-free survival (PFS) using a pre-specified one-sided stratified log rank test at a significance level of 0.02. The stratification factors are International Staging System (ISS) stage (I, II or III) and intent to transplant (yes or no), a total of 6 strata. Overall response rate (ORR), overall survival (OS) and safety are secondary end points. Methods: This analysis includes 474 patients evaluable for survival endpoints: 232 patients were randomized to Rd and 242 patients to VRd. Rd patients received lenalidomide 25 mg/day on days 1-21 and dexamethasone 40 mg/day on days 1, 8, 15 and 22 of a 28-day cycle. VRd patients received lenalidomide 25 mg/day on days 1-14 and dexamethasone 20/mg/day on days 1, 2, 4, 5, 8, 9, 11 and 12 plus bortezomib 1.3 mg/m2 IV push on days 1, 4, 8 and 11 of a 21-day cycle. All patients received aspirin 325 mg/day and VRd patients received HSV prophylaxis per institutional standard. Induction was six 28-day cycles of Rd and eight 21-day cycles of VRd followed by Rd maintenance for all patients until progression, unacceptable toxicity or withdrawal of consent. Initial analyses utilized the pre-specified one-sided stratified log rank test. Results: Data are presented for VRd followed by Rd throughout. Between 2008 and 2012, 525 patients from 48 institutions were randomized. Fifty-one patients, 29 randomized to Rd and 22 randomized to RVd, were ineligible for the following reasons: missing, insufficient or early or late baseline labs (40); not meeting requirements of measurable disease (6); inadequate marrow function (1); inadequate creatinine clearance (1); prior malignancy (1); prior therapy (1); and more than 2 weeks of prior steroid therapy (1). The pre-specified significance level of 0.02 was reached in the log rank testing. The stratified hazard ratio (HR) was 0.742 (96% Wald confidence interval: 0.579, 0.951), and the one-sided stratified log rank p-value for PFS (VRd vs. Rd) was 0.0066. The OS was improved for VRd vs. Rd with HR = 0.666; two-sided log-rank p-value = 0.0114. The PFS and OS survival charts are displayed below. Median PFS was 43 months (VRd) versus 31 months (Rd). Median OS was not reached (VRd) versus 63 months (Rd). Patient characteristics were well-matched between VRd and Rd with the exception of fewer women (37% vs. 47%: P = 0.033) and fewer older patients (≥ 65 years 38% vs. 48%: P = 0.042) receiving VRd. With univariate Cox regression analysis correlates of better PFS/OS were: use of VRd (HR 0.72/0.65; P = 0.006); hemogoblin ≥10 g/dl (HR 1.17/1.43; P = 0.2/0.026) and lower ISS disease stage (HR 1.35/1.98; P = 0.014/< 0.001). The ORR for VRd was 71.07% versus 63.79% for Rd. The adverse events by CTC category and toxicity category were fairly well balanced. The most common hematologic adverse events (≥ Grade 3 and at least possibly attributable to therapy) were low hemoglobin (RVd=13%; Rd=16%), leukopenia (RVd=14%; Rd=16%), lymphopenia (RVd=23%; Rd=18%), neutropenia (RVd=19%; Rd=21%), and thrombocytopenia (RVd=18%; Rd=14%). The most common non-hematologic adverse events (≥ Grade 3 and at least possibly attributable to therapy) were: fatigue (RVd=16%; Rd=14%), sensory neuropathy (RVd=23%; Rd=3%), hyperglycemia (RVd=7%; Rd=11%), thrombosis/embolism (RVd=8%; Rd=9%), hypokalemia (RVd=9%; Rd=6%), muscle weakness (RVd=7%; Rd=4%), diarrhea (RVd=8%; Rd=2%), and dehydration (RVd=8%; Rd=2%). As expected ≥ Grade 3 neuropathy was more frequent with VRd (24% vs. 5%: P < 0.0001). Sixteen patients experienced a second primary malignancy, 7 (3%) on VRd and 9 (4%) on Rd. Conclusion: The addition of bortezomib to lenalidomide dexamethasone for induction therapy in previously untreated myeloma results in a statistically significant and clinically meaningful improvement in PFS as well as better OS. VRd had an acceptable safety and tolerability profile despite increased neurotoxicity and represents a potential new standard of care. Support: NIH/NCI/NCTN grants CA180888, CA180819, CA180821, CA180820; and in part by Millennium Pharmaceuticals, Inc., The Takeda Oncology Company, for provision of study drug. Figure 1. Figure 1. Figure 2. Figure 2. Disclosures Durie: Johnson & Johnson: Consultancy; Takeda: Consultancy; Onyx: Consultancy; Celgene: Consultancy. Abidi:Millennium: Research Funding. Epstein:University of Arkansas for Medical Sciences: Employment. Reu:Takeda/Millennium: Research Funding; Novartis: Research Funding; Celgene: Research Funding. Orlowski:BioTheryX, Inc.: Membership on an entity's Board of Directors or advisory committees; Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Research Funding; Spectrum Pharmaceuticals: Research Funding; Onyx Pharmaceuticals: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Millennium Pharmaceuticals: Consultancy, Research Funding; Acetylon: Membership on an entity's Board of Directors or advisory committees; Genentech: Consultancy; Forma Therapeutics: Consultancy; Array BioPharma: Consultancy, Research Funding. Barlogie:Dana Farber Cancer Institute: Other: Travel Stipend; International Workshop on Waldenström's Macroglobulinemia: Other: Travel Stipend; ComtecMed- World Congress on Controversies in Hematology: Other: Travel Stipend; European School of Haematology- International Conference on Multiple Myeloma: Other: Travel Stipend; Celgene: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Myeloma Health, LLC: Patents & Royalties: Co-inventor of patents and patent applications related to use of GEP in cancer medicine licensed to Myeloma Health, LLC; Multiple Myeloma Research Foundation: Other: Travel Stipend.

Abstract Abstract 1881 Background: Drug-disease modeling and simulation has recently been proposed to support drug development decisions in patients with liquid and solid tumors (Claret et al J Clin Oncol, 27:4103-4108, 2010; Wang et al. Clin Pharmacol Ther, 86:167-174, 2009). We hypothesized that similar modeling based on a decrease in M-protein may be applied in multiple myeloma. The objective was to use a modeling and simulation approach to leverage available lenalidomide multiple myeloma data and support pomalidomide development decisions by, 1) developing a drug-independent link between tumor burden reduction (as assessed by change from baseline in serum M-Protein) and survival and PFS and 2) simulating expected survival and PFS based on interim M-protein data of the phase 1/2 trial (CC-4047-MM02, NCT00833833) of pomalidomide (POM) in patients with relapsed and refractory multiple myeloma who have received at least 2 prior therapies including lenalidomide (LEN) and bortezomib. Methods: M-Protein measurements were modeled as a function of time from 704 patients included in two phase 3 clinical studies of LEN plus dexamethasone (DEX) vs. DEX (MM010, Dimopoulos, NEJM 357, 2123–2132, 2007 and MM009, Weber, NEJM 357, 2133–2142, 2007). Models were developed for survival and PFS times as a function of change in M-protein level at end-of-cycle 2 (week 8) from baseline as well as other prognostic factors. Interim M-protein data from the ongoing MM-002 POM study (217 patients) were modeled to simulate clinical endpoints. Results: Based on lenalidomide Phase 3 data, week-8 change in M-Protein (p < 0.00001), ECOG performance status (p < 0.0009), baseline albumin, hemoglobin and creatinine levels (p < 0.01) were significant independent predictors of survival when week-8 change in M-Protein (p < 0.00001) and baseline hemoglobin (p < 0.001) were significant independent predictors of PFS. Observed survival and PFS distributions over 100 weeks in lenalidomide studies and difference between the two treatments (LEN + DEX vs. DEX) were consistent with the 95% confidence intervals (CI) of the models. Model predictions (95% PIs) of median survival and PFS based on week-8 change in M-Protein following treatment with POM and POM + DEX are presented in the table below. The recently disclosed observed medians and 95% CIs for all endpoints and all arms from MM-002 are included in the model. Conclusions: Change in M-protein level as a continuous longitudinal biomarker appears to be a potential indicator to assess drug effect in multiple myeloma studies using modeling and simulation based on early interim data. PFS predicted by the model and the actual PFS are similar and thus may support end-of-Phase 2 decision (Bruno et al Clin Pharmacol Ther 86:136-138, 2009). Current simulations indicate encouraging results for POM in a refractory multiple myeloma patient population who have received prior treatment that includes lenalidomide and bortezomib but these exploratory methods require confirmation as part of ongoing studies. Disclosures: Bruno: Pharsight: Employment; Celgene Corporation: Research Funding. Off Label Use: Pomalidomide is not an FDA licensed product for multiple myeloma treatment. Jonsson:Pharsight: Employment; Celgene Corporation: Research Funding. Zaki:Celgene Corporation: Employment. Jacques:Celgene Corporation: Employment. Swern:Celgene Corporation: Employment. Richardson:Millennium Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; Novartis Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees. Claret:Celgene Corporation: Consultancy, Research Funding; Pharsight: Employment.

Abstract Abstract 1808 Background: Approximately 50% of the Multiple Myeloma (MM) cases are associated with hyperdiploidy (Hyperdiploid MM, HDMM), usually of the odd numbered chromosomes. The majority of the remaining patients with MM have translocations involving the immunoglobulin heavy chain (IgH) locus on chromosome 14q32 (Translocated MM, TMM).(Fonseca R, Leukemia 2009;23:2210-21) However, most of these estimates are from studies done in predominantly white populations. MM is approximately two fold more common in blacks, and results from the phase 3 study of lenalidomide and dexamethasone suggested that blacks may have better outcome. (Rajkumar SV, Lancet Oncol 2010;11(1):29-37) Goals: The purpose of this study was to determine the cytogenetic characteristics and outcome of MM in blacks, and to compare this with a similar population of white patients seen during the same time period. Methods: We studied African American and African patients with MM diagnosed from May 2002 through June 2010 at John H. Stroger, Jr. Hospital of Cook County (CC), Chicago, IL and comparable Caucasian population seen at Mayo Clinic (MC), Rochester, MN between these dates with available cytogenetic studies (karyotyping and/or fluorescent in situ hybridization (FISH) data) at diagnosis. The results between both populations were then compared. Results: 65 blacks (25 men and 40 women) and 490 Caucasians (290 men and 200 women) with MM were studied. Karyotyping was available in 98% of patients from both cohorts, and FISH was available for 35% and 64% of the CC and MC cohorts, respectively. A molecular classification was possible in 16 (25%) of the CC cohort (12 HDMM, 4 TMM) and 294 (60%) of the MC cohort (38% HDMM, 22% TMM). In the remaining patients, both tests were normal or showed changes not definitive for either IgH translocations or hyperdiploidy. At diagnosis, abnormal cytogenetics by karyotyping was present in 25/65 (38%) of the CC cohort and 154/479 (32%) of the MC cohort. The median overall survival (OS) from diagnosis for the CC and MC cohorts was similar at 64 months. The median OS was significantly shorter for those with an abnormal cytogenetics; 35 months vs. 65 months in the CC cohort (P0.03) and 49 months vs. not reached for the MC cohort (P < 0.01). OS was superior among patients in the CC cohort initially treated with an immunomodulatory agent (IMiD) containing regimen (65 months vs. 35 months for those receiving a bortezomib or other non-IMiD containing regimens (P=0.02; Figure 1). Similarly, in the MC cohort, patients receiving an IMiD based regimen had a superior OS (not reached vs. 42 months; P < 0.001). The use of immunomodulatory therapy did not differ across cytogenetic types. Conclusions: The current study suggests that IgH translocations were less frequently seen in blacks compared with what is typically reported in the literature. This may explain the relatively better survival reported in blacks compared with whites in recent trials. We found a significantly superior outcome in blacks treated initially with regimens containing immunomodulatory agents compared to other regimens. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1882 Introduction: Lenalidomide (L) with dexamethasone (D) has demonstrated activity in untreated symptomatic multiple myeloma (MM) (Rajkumar et al. Lancet Oncol 2010; 11: 29–37). Neutropenia may occur, requiring dose reductions, interruptions, or G-CSF support in up to 20% of patients. Renal clearance accounts for 67% of L elimination, and renal insufficiency is associated with an increased risk of cytopenias. Product information recommends the use of the Cockcroft-Gault (C-G) equation for creatinine clearance (CrCL) estimation for initial dosing; however, other estimates including the Modification of Diet in Renal Disease (MDRD) method may be more accurate. We evaluated the impact of renal function on L dosing, cytopenias, and response in patients on the Eastern Cooperative Group (ECOG) E4A03 study. Methods: All patients (n=445) enrolled on E4A03 were included in this analysis. Clinical data at baseline and after 4 cycles was reviewed. Renal function over the first 4 treatment cycles was estimated using both last reported on cycle 4 and last ever reported serum creatinine (SCr) as the former method resulted in a loss of 70 more patients. Patients were classified by CrCL (mL/min) stage: (1) ≥90 (2) 60–89 (3) 30–59 (4) 15–29 (5) <15. Patients were further categorized into CrCL groups collapsing stages 3–5 while maintaining division of normal status. Demographic and disease data of age, ECOG performance status (PS), sex, race, ISS stage, and complete blood counts were included. Percent of planned L dose and dose interruptions were calculated. Descriptive statistics were used to assess measures at each timepoint. Associations between baseline MDRD, C-G, SCr and patient characteristics were assessed by chi-square testing, and logistic regression models of L dose modification, cytopenias, and response status with renal function measures were created. Results: Mean SCr improved in 361/445 (81%) by 0.23 mg/dL following treatment initiation. Mean MDRD CrCL improved in 264/445 (59%) by 24.3 mL/min. Because only initial weight was captured, C-G estimates over time were not available. ISS stage II/III was associated with baseline elevated SCr (> 1.5 mg/dL) and low CrCL (p<0.001). Dose modification of L occurred in 44% of patients over 4 cycles (Table 1). In adjusted analyses, C-G predicted L dose modifications, p<0.001 [stage 3–5 vs 1 OR 2.09 (1.23-3.55)] along with ECOG PS. Similarly, in adjusted analyses, grade 2–5 cytopenias were better predicted by C-G stage, p<0.001 [stage 3–5 vs 1 OR 5.08 (2.18-11.84)], over MDRD stage, p=0.025 [stage 3–5 vs 1 OR 2.66 (1.07-6.61)]. No association between baseline or change in renal function and ≥ VGPR after 4 cycles was noted. Conclusion: Renal function improvement in patients receiving LD warrants regular CrCL monitoring and L dose increases in patients on reduced doses without cytopenias. Baseline MDRD is not superior to C-G for CrCL estimation for predicting L dosing and cytopenia development. Optimizing L exposure through pharmacokinetic modeling or other methods may further refine dosing. Disclosures: Lonial: Millenium: Consultancy; Celgene: Consultancy; Novartis: Consultancy; Bristol Myers Squibb: Consultancy; Onyx: Consultancy; Merck: Consultancy.

Abstract Abstract 1572 Background: The incidence of histologic transformation (HT) of follicular lymphoma (FL) to an aggressive lymphoma has been reported to range from 10–75%. The British Columbia Cancer Agency reported a risk of 3% per year (Al-Tourah AJ, et al J Clin Oncol 2008;26: 5165–5169). The hallmark of HT is the acquisition of new somatic mutations and genomic instability within the malignant clone. DNA damaging agents such as radioimmunotherapy (RIT) may increase the risk of HT by inducing additional DNA damage. The incidence of HT after RIT is unknown. This single institution study analyzes the risk of histologic transformation (HT) in patients with FL after RIT treatment with yttrium-90 ibritumomab tiuxetan. METHODS: The Mayo Clinic Lymphoma Data Base were queried for all patients having received a single dose of yttrium-90 ibritumomab tiuxetan for FL. The Mayo Clinic Lymphoma Database includes all consecutive adult patients diagnosed with lymphoma evaluated at Mayo Clinic Rochester. The prospective radioimmunotherapy lymphoma database was also utilized (GAW). The diagnosis of FL was defined by current WHO Classification, and all cases were centrally reviewed. HT was defined as the development of histologically proven diffuse large B cell lymphoma in patients with history of Grade 1 or 2 FL (change to Grade 3A/B FL was not included). Patients having demonstrated evidence of HT prior to RIT were excluded from this analysis. RESULTS: 119 consecutive patients were included. 64(54%) were male. The median follow-up was 57(range 2–175) months. RIT was administered as treatment for progressive FL in 96.6% of patients. RIT was administered as a consolidation therapy in 4(3.4%) patients. The median number of prior systemic treatments was 2 (range 0–10). The median time from diagnosis to RIT was not different in patients with HT vs. those without HT 44 (10–186) vs. 40 months (range 1–394) (p=0.30), respectively. The median time to HT from RIT was 13 months (range 1–97). Four patients had HT within 3 months of RIT. The median survival after HT was 15 months (range 1–147). The estimated five year risk of transformation from RIT by Kaplan-Meier in patients with fludarabine exposure and those without exposure was 55% and 29% (p=0.0498). 10 year risk from the time of RIT was 64% with fludarabine exposure and 31% without (p=0.0498). The relative risk of HT after RIT in patients previously treated with fludarabine was HR=4.1 (95% CI: 2.0–7.9). The median number of prior therapies in patients with HT vs. patients without HT was 2 (0–6) and 1 (0–10) (P=0.33). CONCLUSIONS: To our knowledge, our data is the first to estimate the risk of HT after the use of RIT. The estimated overall risk of HT of 31% at 10 years from diagnosis in patients without fludarabine exposure is similar to that of patients in whom RIT has not been administered. The estimated overall risk of HT of 64% in those patients having received purine analogues appears to be increased. We conclude that RIT appears to not increase the risk of HT in patients who did not receive prior purine analogue therapy. The differences in extent and mechanisms involved in DNA damage induced by radiation vs. purine analogues may play a role in clinical differences in observed rates of HT. Disclosures: No relevant conflicts of interest to declare.