Hofmeister, Craig C.

Abstract Introduction Few treatments options are available for patients (pts) with relapsed/refractory multiple myeloma (RRMM) who have previously been treated with lenalidomide (LEN) and bortezomib (BORT), and their prognosis is poor. Pomalidomide (POM) is a distinct IMiD® immunomodulatory agent with a mechanism of action consisting of direct anti-myeloma, stromal-support inhibitory, and immunomodulatory effects. In randomized phase 2 and 3 trials (MM-002 and MM-003), POM plus low-dose dexamethasone (POM+LoDEX) demonstrated marked efficacy in RRMM pts who had received multiple prior therapies, including LEN and BORT. This side-by-side analysis presents the most recent survival and safety data from these trials. Methods The MM-002 and MM-003 trials enrolled pts with ≥ 2 prior therapies, including LEN and BORT. In MM-002, pts received POM (4 mg/day on days 1–21 of each 28-day cycle) alone or in combination with LoDEX (40 mg/week). In MM-003, pts were randomized 2:1 to receive POM+LoDEX or high-dose DEX alone (HiDEX) (40 mg/days 1–4, 9–12, 17–20 in a 28-day cycle); HiDEX was chosen as the comparator to isolate the effects of POM, as at the time of trial design it was the standard salvage therapy for heavily pretreated pts. Thromboprophylaxis was required for all pts treated with POM and pts at high risk of developing venous thromboembolism. Data cutoff was February 1, 2013 for MM-002 and March 1, 2013 for MM-003. The primary endpoint in both trials was progression-free survival (PFS). Secondary endpoints included overall survival (OS), response rates, duration of response, and safety. Results In each study, pts had received a median of 5 prior therapies (range 1-17), and all pts had received prior LEN and BORT. In MM-002, 113 pts were treated with POM+LoDEX and 108 were treated with POM alone (60% of POM alone pts subsequently received DEX). A total of 79% of pts were LEN refractory; 62% were refractory to both LEN and BORT; and 35% had received LEN as their last prior therapy. With a median follow-up of 14.2 months (mos), median PFS was 4.2 mos, OS was 16.5 mos, and overall response rate (ORR, defined as at least a partial response) was 33% with POM+LoDEX (Table 1). In MM-003, 302 pts were treated with POM+LoDEX and 153 pts were treated with HiDEX (50% of HiDEX pts subsequently received POM). A total of 94% of pts were LEN refractory; 74% were both LEN and BORT refractory; and 29% had received LEN as their last prior therapy. Survival outcomes were similar in MM-003; with a median follow-up of 10 mos, median PFS was 4.0 mos, OS was 12.7 mos, and ORR was 31% with POM+LoDEX. In both trials, LEN as last prior therapy did not impact response, PFS, or OS vs the overall population. Commonly observed adverse events (AEs) are presented in Table 2 for pts treated with POM+LoDEX. Grade 3 and 4 neutropenia was 28% and 13% in MM-002, and 26% and 22% in MM-003 for the POM+LoDEX arms, respectively. AEs were generally manageable for POM+LoDEX in MM-002 and MM-003 with dose interruptions (67% for both) and reductions (29% and 26%, respectively), and standard supportive care, including growth factor support (46% and 43%), red blood cell transfusions (45% and 49%), platelet transfusions (14% and 20%), and anti-infective agents (89% in both trials). Rates of POM discontinuation due to treatment-related AEs were low (2–4% with POM+LoDEX). In MM-002 and MM-003, 49% and 51% of pts in the POM+LoDEX arms experienced neutropenia of any grade. With appropriate AE management, 9% and 23% had dose interruptions, 4% and 8% had dose reductions, and 1 pt in both MM-002 and MM-003 discontinued due to neutropenia. Febrile neutropenia developed in 3% and 10% of pts; 1% and 4% had dose interruptions, 0% and 2% had dose reductions, and no pts discontinued due to febrile neutropenia in the MM-002 and MM-003 studies, respectively. The majority of infections occurred in the absence of neutropenia of any grade (54% in MM-002 and 66% in MM-003). The rate of POM discontinuation due to infection was low (1% in MM-002 and 2% in MM-003). Conclusion In both the MM-002 and MM-003 trials, POM+LoDEX consistently extended PFS in advanced RRMM pts. PFS, OS, and ORR were not negatively impacted in patients who were refractory to LEN or BORT, even as last prior therapy. Both trials demonstrated that with dose modifications and supportive care POM was well tolerated, leading to few discontinuations. POM+LoDEX should be considered a standard of care for pts with advanced RRMM who have exhausted LEN and BORT. Disclosures: Siegel: Celgene Corporation: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Onyx: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Millennium: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Richardson:Millennium: Membership on an entity’s Board of Directors or advisory committees; Johnson & Johnson: Membership on an entity’s Board of Directors or advisory committees; Celgene Corporation: Membership on an entity’s Board of Directors or advisory committees. Dimopoulos:Celgene Corporation: Honoraria, Membership on an entity’s Board of Directors or advisory committees. Chen:Celgene Corporation: Consultancy, Honoraria, Research Funding. Song:Celgene Corporation: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau. Vij:Onyx: Consultancy, Research Funding; Millenium: Speakers Bureau; Celgene Corporation: Consultancy, Research Funding, Speakers Bureau. Bahlis:Celgene Corporation: Consultancy, Honoraria, Research Funding. Baz:Millenium: Research Funding; Bristol Myers Squibb: Research Funding; Novartis: Research Funding; Karyopharm: Research Funding; Sanofi: Research Funding; Celgene Corporation: Research Funding. Hofmeister:Celgene Corporation: Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Weisel:Celgene Corporation: Consultancy, Honoraria, Research Funding. Jagannath:Millennium: Honoraria; Celgene Corporation: Honoraria. Lonial:Millennium: Consultancy; Novartis: Consultancy; Bristol Myers Squibb: Consultancy; Sanofi: Consultancy; Onyx: Consultancy; Celgene Corporation: Consultancy. Delforge:Celgene Corporation: Honoraria. Talpaz:Ariad, Sanofi, Novartis: Membership on an entity’s Board of Directors or advisory committees; Ariad, Novartis, BMS, Pfizer: Speakers Bureau; Ariad, BMS, Sanofi, INCYTE: Research Funding. Moreau:Celgene Corporation: Honoraria, Speakers Bureau. San Miguel:Jansen, Celgene Corporation, Onyx, Novartis, Millenium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees. Karlin:Janssen: Honoraria; Celgene Corporation: Consultancy, Expert board committee Other, Honoraria. Goldschmidt:Celgene Corporation, Janssen, Novartis: Consultancy, Honoraria, Research Funding. Oriol:Celgene Corporation: Consultancy. Alegre:Janssen: Membership on an entity’s Board of Directors or advisory committees, Research Funding; Celgene Corporation: Membership on an entity’s Board of Directors or advisory committees, Research Funding. Cavo:Millennium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Onyx: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Celgene Corporation: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees. Martinez-Lopez:Celgene Corporation: Honoraria, Research Funding. Lacy:Celgene Corporation: Research Funding. Chen:Celgene Corporation: Employment, Equity Ownership. Casey:Celgene Corporation: Employment, Equity Ownership. Sternas:Celgene Corporation: Employment, Equity Ownership. Zaki:Celgene Corporation: Employment, Equity Ownership. Jacques:Celgene Corporation: Employment, Equity Ownership. Anderson:Onyx: Consultancy, Equity Ownership; Gilead: Consultancy, Equity Ownership; sanofi aventis: Consultancy, Equity Ownership; Oncopep: Consultancy, Equity Ownership; Acetylon: Consultancy, Equity Ownership; Celgene Corporation: Consultancy, Equity Ownership.

Abstract Abstract 1024 Background: The MMRC is a non-profit, disease-focused consortium founded in 2004. Sixteen North American member institutions with expertise in multiple myeloma (MM) work collaboratively with the MMRC Inc. (Norwalk, CT) and numerous pharmaceutical partners to speed development of new treatment options to MM patients. In December 2007, MMRC Inc. implemented business solutions to address barriers to rapid activation of phase I-II trials and established benchmarks for initiating and conducting these studies. In December 2010, we reported significantly faster trial start up and accrual data from previous years1,2. Today, we update and expand on MMRC performance data and analysis of progress. Methods: Twenty-five (25) trials conducted within the Consortium from May 2006 to July 2011 had sufficient start up trial data for review. FPFD was defined as the time from the member institutions' receipt of the final protocol (FP) from the trial sponsor, to the time the first patient was dosed on the trial at any participating MMRC member institution. With respect to enrollment, pre-study enrollment commitment (EC) established between MMRC and the study sponsor was defined as the total number of subjects committed to receive at least one dose of study drug across all participating MMRC centers on a trial; baseline enrollment timeline (BET) was prospectively defined as the target time period to attain EC. Results: Mean time to FPFD in the recent group of trials (RG; n=18; Sept 08-Jul 11) held steady at 131 calendar days from receipt of FP as compared to 181 days for the early group of trials (EG; n=7; Jun06-Sept08) representing a 28% reduction in time to FPFD. More importantly, there was a 20% decrease in time to FPFD by all participating MMRC centers on any MMRC trial from 189 days in the RG compared to 236 days in the EG representing an important achievement especially in the Phase I/II arena. MMRC trial accrual data was available for 17/25 trials (2 EG trials were missing data and 6 RG trials continue enrolling). The pre-study mean MMRC EC was 44 subjects per trial (n=19 trials; 849 patients); the mean actual MMRC enrollment was 49 subjects per trial (n=19; 935 patients through July 11) representing a 10% over enrollment versus committed enrollment. A total of 17/19 evaluable trials (89%) met their EC; 12/19 trials met EC within BET (71%) of which 8/12 trials (67%) reached EC 34% faster than their BET (representing a mean reduction of 4.5 months). The overall pre-study mean BET for 19 trials was 13.6 months. MMRC's actual mean enrollment timeline was 12.8 months for the group of 17 evaluable trials representing improvement over the original BET by a mean of 10%. Discussion: MMRC's acceleration of clinical trials provides physicians and patients with rapid access to novel compounds; industry with data for important drug development decisions; and academic institutions with more trials of high scientific interest. Even so, our data uncovered opportunities for improvement. The submission time from receipt of the final protocol from the trial sponsor to Scientific Review Committee (SRC) took an average 30 calendar days across all trials. A reduction to half this time could make a difference to patients and therefore warrants further exploration. Conclusion: Today, drug development in multiple myeloma is fast-paced and highly competitive. MMRC's frequent review of trial metrics provides valuable insight to continually speed answers to physicians, patients and industry. Disclosures: Richardson: Multiple Myeloma Research Consortium: Annual grant in support Clinical Trial Project Management. Vij:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Lonial:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Siegel:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Jakubowiak:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Reece:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Jagannath:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Hofmeister:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Stewart:Multiple Myeloma Research Consortium: Annual Grant in support of clinical trial Project Management. Wolf:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Krishnan:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Zimmerman:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Kumar:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Roy:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Fay:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management. Anderson:Multiple Myeloma Research Consortium: Annual grant in support of clinical trial Project Management.

Abstract Abstract 4919 Waldenstrom's macroglobulinemia (WM) is characterized by the presence of lymphoplasmacytic cells in the bone marrow and the secretion of IgM monoclonal antibody in the serum. Several conventional therapies are available but the disease remains incurable. Recently, bortezomib (a proteasomal inhibitor) has shown promising anti-WM activity with enhanced responses when combined with traditional therapies. Resistance to bortezomib therapy is an important event that is associated with continued treatment. In order to understand the mechanism of bortezomib resistance in WM we exposed BCWM.1 (a known WM cell line) in vitro to increasing concentrations of bortezomib over prolonged periods of time and isolated the bortezomib resistant clone (BCWM.1/BR). This clone was compared with its parent wild type cell line (BCWM.1/WT). Investigation to understand the susceptibility of BCWM.1/Br cells to various therapeutic agents showed that these cells are resistant to many of the agents such as melaphalan, fludarabine or doxorubicin. Interestingly, verapamil, a broad spectrum inhibitor of multidrug resistance, failed to reverse the resistance induced by bortezomib indicating that bortezomib resistance is not because of an activation of multidrug resistance in these cells. While BCWM.1/WT cells showed an IC50 of 7.8nM when treated for 72h with bortezomib, the BCWM.1/BR cells were not inhibited at any concentration of the compound up to 100nM. Furthermore, the cells with the acquired resistance showed a 4 fold increase in the proteasomal activity as measured by the release of a fluorescent product (7-Amino-4-methylcoumarin (AMC)) from its peptide substrate, suc-LLVY-AMC. Biochemical analysis further revealed that many of the proteasomal components are altered in BCWM.1/BR cells as compared to their parental control cells. Interestingly, protein levels of two of the proteasomal catalytic subunits, PSMB5 and PSMB9 are upregulated in resistant cells suggesting a reason for the enhanced proteasomal activity of these cells. The resistant cells showed an altered gene expression profile that indicates a transformation of the parental wild type cell line to acquire resistance. A comparative analysis of the signal transduction pathways operated in these cells showed that many of the activation and cell survival pathways that are present in BCWM.1 cells are inhibited in the resistant cells. For example, BCWM.1 cells show a constitutive activation of AKT and ERK1/2 which are inhibited in the resistant cells thus making them insensitive to the inhibitors of these pathways. Similarly, HSP27 which was earlier shown to contribute to bortezomib induced resistance was completely inhibited in BCWM.1 resistant cells. Interestingly, there is an increase in Bcl-2 protein in BCWM.1/BR cells as compared to WT cells indicating that the resistant cells might be dependent on Bcl-2 family for their survival. Inhibition of Bcl-2 induced potent apoptosis in BCWM.1/BR cells. Thus the results presented here indicate that acquired bortezomib resistance in BCWM.1 cells alters their proteasomal activity, cellular signaling pathways to make them resistant to many of the known therapies but these cells retain the Bcl-2 mediated pathway for targeting thus inhibitors of Bcl-2 may be used in therapy against bortezomib-resistant WM. Disclosures Chanan-Khan: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Immunogen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Abstract Abstract 3701 Background: Waldenstrom's macroglobulinemia (WM) is an indolent B-cell non-Hodgkin's lymphoma (B-NHL) characterized by production of a monoclonal IgM paraprotein and variable CD20 expression due to the downregulation of CD20 as B cells differentiate into plasma cells. Rituximab monotherapy (R) achieves an overall response rate (ORR) of 25–50% in therapy naïve and relapsed WM and is associated with IgM flares in 25–75% of patients (pts) that potentially lead to hyperviscosity due to a rapid rise in IgM. Ofatumumab (OFA) is a fully human monoclonal anti-CD20 antibody approved for the treatment of fludarabine and alemtuzumab-refractory chronic lymphocytic leukemia (CLL) and has demonstrated activity in indolent B-NHL. Since OFA is active in CLL, with its low CD20 expression, we initiated a phase II single-arm trial of OFA in pts with WM. We report primary endpoint data from this study. Methods: Pts (age ≥ 18 years) with WM requiring therapy by 2nd International Workshop on WM (IWWM) criteria were eligible. Cycle 1 (C1) of therapy consisted of OFA 300 mg week 1 and 1000 mg weeks 2–4 (Treatment Group A [TGA]) or OFA 300 mg week 1 and 2000 mg weeks 2–5 (TGB). Premedication included acetaminophen and antihistamine (all infusions) and glucocorticoid (infusions 1 and 2). Pts with grade 3–4 infusion-related adverse events (AEs) during weeks 1 and 2 also received glucocorticoid during weeks 3–5. Pts with stable disease (SD) or a minor response (MR) at week 16 of cycle 1 were eligible to receive a re-dosing cycle (C2) consisting of OFA 300 mg week 1 and 2000 mg weeks 2–5. The primary endpoint was ORR assessed by 3rd IWWM criteria. Toxicity was assessed according to NCI-CTCAE, v 3.0. Results: Thirty-seven pts were enrolled between March 2009 and February 2011. Median age was 63 years (range 43–85); 22 pts were male. Median IgM level was 3.11 g/dL (range 0.81–8.64); median hemoglobin (hgb) was 9.8 g/dL (range 5.3–13.2). Nine pts were treatment naïve; 28 pts had received a median of 3 prior therapies (range 1–5) including R (25 pts) and purine analog (14 pts). The first 15 pts were enrolled in TGA and the next 22 pts in TGB; pt characteristics were similar in both groups. Thirty-four pts completed C1; 1 pt withdrew after 1 dose and 2 pts received only 3 doses due to serious AEs (SAEs). Eleven pts achieved partial response (PR) and 7 achieved MR after C1 (ORR=49%; 95% CI [32%, 66%]). Twelve pts received C2, after which 4 pts improved their response (1 MR to PR, 1 SD to PR, 2 SD to MR) and 1 nonevaluable pt attained MR. After C1 and C2, the ORR was 59% (13 PR, 9 MR; 95% CI [42%, 75%]). Responses were seen in 67% (6/9) of therapy naïve pts, 57% (16/28) of relapsed pts, 52% (13/25) of pts who had prior R, 75% (9/12) of R-naïve pts, 64% (16/25) of pts with IgM < 4 g/dL and 50% (6/12) of pts with IgM ≥ 4 g/dL. ORR was 47% (7/15) in TGA and 68% (15/22) in TGB. ORR in TGA was negatively affected by prior R exposure and IgM ≥ 4 g/dL, whereas ORR in TGB was not affected by prior therapy, prior R or IgM level. Fifteen of 26 (58%) pts with hgb < 11.0 g/dL experienced ≥ 3.0 g/dL increase in hgb (range 3.0–7.1). Infusion-related events occurred with dose 1 in 30 (81%) pts and with dose 2 in 21 (57%) pts; all infusion events were grade 1–2 except 4 grade 3 events (1 rash, 1 chest pain, 1 chest discomfort, 1 back pain). Fifteen pts developed 22 infections including 8 upper respiratory tract, 4 urinary tract (UTI) and 4 sinus infections; all infections were grade 1–2 except 1 grade 3 UTI. One pt developed grade 3 febrile neutropenia. In total, there were 14 grade 3–4 AEs (all grade 3). Five pts developed 8 SAEs possibly related to OFA. One pt withdrew due to grade 3 hemolytic anemia. Two pts with baseline IgM of 6.63 and 4.75 g/dL required plasmapheresis for grade 3 renal insufficiency and hyperviscosity symptoms, respectively, with resolution of symptoms and were able to complete C1. Two pts developed IgM flare, defined as > 25% rise in IgM followed by subsequent MR or PR. Conclusions: OFA is clinically active in pts with WM, with an acceptable toxicity profile and a lower incidence (5%) of IgM flare. The ORR to OFA was 59% (TGA 47%, TGB 68%) including a 50% ORR (TGA 17%, TGB 83%) in pts with IgM ≥ 4.0 g/dL. Pts' anemia responded to OFA with 58% of pts with baseline hgb < 11.0 g/dL experiencing ≥ 3.0 g/dL increase in hgb. TGB achieved ORR > 60% in all pt groups regardless of prior therapy or baseline IgM level. A higher dose of OFA appeared to be more effective in pts previously exposed to R or with baseline IgM ≥ 4.0 g/dL. Further study of OFA in WM is warranted. Disclosures: Furman: Genentech: Speakers Bureau; GlaxoSmithKline: Speakers Bureau. Off Label Use: • Ofatumumab is an anti-CD20 monoclonal antibody approved for the treatment of fludarabine- and alemtuzumab-refractory chronic lymphocytic leukemia, and is currently under development for the treatment of B-cell malignancies (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, Waldenstroms macroglobulinemia and follicular lymphoma), as well as autoimmune diseases (rheumatoid arthritis and multiple sclerosis). Eradat:Millennium: Speakers Bureau; Genentech, A Roche Company: Speakers Bureau. DiRienzo:GlaxoSmithKline: Employment. Leonard:GlaxoSmithKline: Consultancy. Advani:GSK: Research Funding. Switzky:GlaxoSmithKline: Employment. Liao:GlaxoSmithKline: Employment. Shah:GSK: Employment. Lisby:Genmab A/S: Employment. Lin:GlaxoSmithKline: Employment.

Abstract Abstract 3803 Background: The MMRC is a non-profit, disease-focused consortium founded in 2004 comprised of 13 North American centers with expertise in multiple myeloma (MM). The MMRC Inc. (Norwalk, CT), MMRC's member institutions, and several pharmaceutical partners work closely to speed early development of new treatment options for MM patients. In December 2007, MMRC headquarters staff implemented multiple project management (PM) business solutions to address trial barriers that delay activation of our phase I-II clinical trials and established trial metric benchmarks considered attainable at our member institutions. In November 2009, we reported initial data1 on trial activation: MMRC trials initiated between Sep08-Jul09 (n=5) demonstrated a 38% decrease in mean time to first patient dosed (FPFD), compared with the Early Group trials (EG) initiated before PM solutions (Jun06-Sept08; n=7 trials). These results also confirmed improvement over published metrics from Dilts et al 2,3. We present additional data on time to FPFD and now enrollment, to assess impact of the MMRC PM resources and processes on trial efficiency. Methods: Twenty-one (21) trials conducted within the MMRC from May 2006 to June 2010 had sufficient trial data for review. Data were collected by MMRC-funded project managers at the clinical centers using a web-based clinical trial management system (CTMS). FPFD was defined as the time from the member institutions' receipt of the final protocol (FP) from the trial sponsor, to the time the first patient was dosed on the trial at any participating MMRC member institution. With respect to enrollment, pre-study enrollment commitment (EC) established between MMRC and the study sponsor was defined as the total number of subjects committed to receive at least one dose of study drug across all participating MMRC centers on a trial; baseline enrollment timeline (BET) was prospectively defined as the target time period to attain EC. Results: Mean time to FPFD was 181 calendar days for the early group trials (EG, n=7) and 122 days for the recent group (RG) trials (n=14, Sep08 – Jun10), representing a 32% reduction of time to FPFD in the RG. Additionally, time from final protocol to first patient dosed at all MMRC centers on a trial decreased 18% from a mean of 7.7 months (EG) to 6.3 months (RG). With respect to MMRC trial enrollment, data was available for 16/21 trials (5 EG and 11 RG). 2 EG trials were missing data and 3 RG trials were still enrolling as of June 2010. The mean MMRC pre-study EC was 39 subjects per trial (n=16 trials; 626 enrollment target); the mean actual MMRC enrollment was 49 subjects per trial (n=16; 783 enrolled through Jun 29, 2010) representing a 25% increase in actual versus committed enrollment. Two trials did not meet MMRC EC: MMRC investigators discontinued their involvement in these trials at approximately 30% target EC due to trial complexity or low patient enrollment. 14/16 evaluable trials (88%) met their EC; 11/16 trials met EC within BET (69%) of which 8/16 trials (50%) reached EC 34% faster than their BET (representing a mean reduction of 4.5 months). The overall pre-study mean BET for 16 trials was 13.1 months. MMRC's actual mean enrollment timeline was 11.3 months for the group of 14 evaluable trials representing improvement over the original BET by a mean of 1.9 months (14%). We believe FP to FPFD is a more meaningful metric beyond that of first patient consented. Moreover, we believe that if all participating trial centers focus their efforts on dosing the first patient and within a targeted timeframe, it may improve our research efforts overall. Conclusion: Development of drugs in the clinical setting has become time and resource intensive. Activating and enrolling trials promptly is a priority for drug development. The MMRC's standardization of processes and support for site-based PM resources results in improved trial metrics. MMRC member centers met or exceeded pre-specified enrollment targets in 88% of the trials analyzed to date. Ongoing monitoring of trial conduct continues to reveal areas where increased focus is needed to realize further trial efficiencies. These trial metrics and measures to improve efficiency may be applied with similar expected benefit in all oncology disciplines. Disclosures: Wear: Multiple Myeloma Research Consortium (MMRC): Employment. Richardson:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC; Millennium: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees. Revta:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Vij:Multiple Myeloma Research Consortium (MMRC): Research Funding; Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Fiala:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Lonial:Bristo-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millenium Pharmaceuticals Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Francis:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Siegel:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC; Celgene: Speakers Bureau; Millennium: Speakers Bureau. Schramm:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Jakubowiak:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC, Research Funding; Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Speakers Bureau; Centocor Ortho-Biotech: Honoraria, Speakers Bureau; Exelixis: Honoraria, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Harvey:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Reece:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC; Celgene: Honoraria, Research Funding; Ortho Biotech: Honoraria, Research Funding; Merck: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Facet: Research Funding; Otsuka: Honoraria, Research Funding. Gul:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Jagannath:Celgene: Honoraria; Millenium: Honoraria; Orthobiotec: Honoraria; Onyx Pharma: Honoraria; Merck: Honoraria; Proteolix: Honoraria; Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. La:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Hofmeister:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Jansak:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Stewart:Millennium: Consultancy; Celgene: Honoraria; Multiple Myeloma Research Consortium: Member Institution of the MMRC. Hagerty:Mayo Clinic: Employment; Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Wolf:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC; Celgene: Speakers Bureau; Millennium: Speakers Bureau; Novartis: Speakers Bureau; Orthobiotech: Speakers Bureau. Davis:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Krishnan:Celgene: Speakers Bureau; Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Duarte:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Zimmerman:Millennium, Celgene: Speakers Bureau. Cisneros:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding; Bayer: Research Funding; Multiple Myeloma Research Consortium: Member Institution of the MMRC. Birgin:Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC. Ott:Multiple Myeloma Research Consortium (MMRC): Employment. Tasca:Multiple Myeloma Research Consortium (MMRC): Employment. Kelley:Multiple Myeloma Research Consortium (MMRC): Employment. Anderson:Millennium: Consultancy; Multiple Myeloma Research Consortium (MMRC): Member Institution of the MMRC; Celgene: Consultancy; Novartis: Consultancy; Onyx: Consultancy; Merck: Consultancy; Bristol-Myers Squibb: Consultancy; Acetylon: Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Giusti:Multiple Myeloma Research Consortium (MMRC): Employment.

Abstract Abstract 1859 Genome wide RNA interference studies identified Aurora Kinase (AURK) A and B as lethal targets in Multiple Myeloma (MM) while suppression of these genes also sensitized MM to bortezomib (BTZ). MLN8237 is an oral inhibitor of AURKA. We therefore conducted a Phase I clinical trial of MLN8237 in combination with BTZ. The study enrolled a total of 19 patients at 5 institutions. 9 patients are still receiving active treatment as of the date of this report. Study Design: The phase I portion of this study uses a standard 3+3 design to determine the maximum tolerated dose (MTD) of MLN8237 and BTZ in patients with relapsed/refractory MM. Eligibility required a minimum of 1 and maximum of 4 lines of prior therapy. Patients who have received prior BTZ therapy were allowed on trial as long as they did not progress during prior BTZ or ≤ 60 days of therapy discontinuation. The following laboratory values were required £7 days prior to registration. ANC3 1000/mL, Hgb ≥9 g/dl, PLT3 100,000/mL, Total bilirubin £1.5 × upper limit of normal (ULN), Creatinine £ 2.5 × ULN, a baseline LVEF ≥45%. Patients were required to be able to take oral medication and to maintain a fast as required for 2 hours before and 1 hour after MLN8237 administration. Treatment Overview: The first 3 patients received MLN8237 at 25 mg po days 1–14 and BTZ at 1.3 mg/m2/dose iv. days 1, 4, 8, 11 on a 28 day schedule. Based on data from other concurrent trials an amendment changed dosing of MLN8237 to 20, 30, 40 or 50 mg po twice daily on days 1–7 and BTZ was given at 1.5mg/m2 iv weekly on a 28 day schedule. Results: Median age of patients was 64, 63% were male, 31% had high risk genetics, 84% had prior stem cell transplant, 53% of patients were relapsed and 47% were relapsed and refractory to therapy. No DLTs were observed even at the highest dose level tested. However, one patient at the highest dose level required a platelet transfusion in order to initiate treatment on time in Cycle 2. Thus, a further 3 patients accrued at the highest dose level before declaring the MTD and proceeding to phase II. The highest dose level (Dose Level 3: MLN8237 50 mg po twice daily on days 1–7; BTZ 1.5 mg/m2 iv. given on days 1, 8, 15, 22) was the final dose level tested (the MTD of single agent MLN8237 is 50mg as defined in other Phase I trials). The ORR was 26% (1 CR, 4 PR); when minor responses are included the ORR was 52%. Median follow up was 4.3 months (range 0.9–23.4) and PFS was 5.5 months. At last follow up 12 patients showed no progression and 7 had progressed. Toxicity: 63% of patients experienced a grade 3AE and 5% a grade 4 AE. Grade 3 or 4 toxicity seen in more than one patient was all hematologic with thrombocytopenia and neutropenia being common. Other toxicity of any grade regardless of attribution occurring in more than 20% of patients included neuropathy 63%, fatigue 63%, diarrhea 53%, nausea 47%,vomiting 26%, infection 32%, alopecia 21%, Conclusions: The MTD of the combination is MLN8237 50 mg po twice daily on days 1–7 and BTZ at 1.5mg/m2 iv weekly. Phase II testing is underway and updated results will be presented. Disclosures: Stewart: Millenium: Consultancy, Honoraria, Research Funding; Onyx: Consultancy; Celgene: Consultancy. Vij:Millennium: Speakers Bureau. Hofmeister:Celgene: Advisory board Other, Honoraria.

Abstract Abstract 1795 Background: Waldenstrom's macroglobulinemia (WM) is an indolent B-cell lymphoma characterized by a heterogeneous population of lymphocytes, plasmacytoid lymphocytes and plasma cells with variable CD20 expression. Rituximab (R) achieves an overall response rate (ORR) of 25–50% in relapsed/refractory WM and is associated with IgM flares, manifested by a rapid rise in IgM, potentially leading to complications of hyperviscosity. Ofatumumab (OFA) is a fully human monoclonal antibody that targets an epitope encompassing both the large and small extracellular loops of CD20 and effectively induces complement-dependent cytotoxicity of B-lymphoma cells. OFA is approved for the treatment of fludarabine- and alemtuzumab-refractory chronic lymphocytic leukemia (CLL) and has demonstrated clinical activity in non-Hodgkin's lymphoma. Given the efficacy of OFA in CLL, with its decreased CD20 antigen density, similar to WM where CD20 is down-regulated with differentiation of cells into plasma cells, a Phase II, open-label, single-arm trial of OFA in patients (pts) with WM was initiated to examine the safety and efficacy of OFA in this population. We report data from a planned interim analysis, which was performed to examine IgM flare, toxicity and response data. Methods: Pts (age ≥18 years) with WM requiring therapy by 2nd International Workshop on WM criteria were eligible. Pts received OFA 300 mg week 1 and 1000 mg weeks 2–4. Premedication included acetaminophen and antihistamine (all infusions) and glucocorticoid (infusions 1 and 2). Pts who experienced grade 3–4 infusion-related adverse events (AEs) during weeks 1 and 2 also received glucocorticoid during weeks 3 and 4. The primary endpoint was ORR assessed by 3rd International Workshop on WM criteria, and toxicity was assessed according to NCI-CTCAE, v3.0. Results: Fifteen pts were enrolled between March 2009 and January 2010. Median age was 59 years (range 43–85), and 9 pts were male. Pts had a median IgM level of 3.70 g/dL (range 1.21–6.62) and median hemoglobin (hgb) of 9.8 g/dL (range 5.3–11.7). Three pts were previously untreated; 12 pts had received a median of 3 therapies (range 2–5), including 11 pts who had received R, and 7 pts who had received a purine analog. Fourteen pts completed all 4 infusions of OFA. One pt withdrew from study after infusion 3 due to a drug-related serious AE (SAE). One pt had cryoglobulinemia, which interfered with IgM assessment. Of the 14 pts with evaluable IgM levels, 3 achieved partial response (PR), and 3 achieved minor response (ORR=43%) 8 weeks to 5 months after start of OFA therapy. One of 3 previously untreated pts and 5 of 12 relapsed pts responded. Four of 11 pts who had received prior R and 2 of 4 R-naïve pts responded. Five of 9 pts with IgM <4 g/dL and 1 of 5 pts with IgM >4 g/dL responded. Four pts with a median hgb of 8.0 g/dL (range 5.3–9.2) experienced ≥2.8 g/dL increase in hgb, including 3 pts who had >5 g/dL increase; median time to reach hgb ≥11.0 was 4 weeks. Infusion-related events occurred with dose 1 (300 mg) in 12 pts and with dose 2 (1000 mg) in 7 pts; all infusion events were grade 1–2 except 2 grade 3 events (rash, serum sickness). Nine pts developed 11 infections: 7 URI, 2 UTI, 1 sinusitis, 1 oral candidiasis (all grade 2). One pt developed grade 3 febrile neutropenia. Two pts developed SAEs possibly related to OFA. One pt developed grade 3 Coombs-negative hemolytic anemia after infusion 3 resulting in study withdrawal, and 1 pt with a baseline IgM level of 6.62 g/dL developed grade 3 renal insufficiency due to a rapid rise in IgM and cast nephropathy 6 weeks after starting OFA. One additional pt, with a baseline IgM level of 4.69 g/dL, developed a rapid rise in IgM and hyperviscosity symptoms. Both pts with a rapid rise in IgM underwent plasmapheresis with resolution of symptoms. No other OFA-related hematologic toxicity was observed. Conclusions: OFA has an acceptable toxicity profile, although a rapid rise in IgM requiring plasmapheresis was observed in 2 pts with high baseline IgM levels. OFA shows clinical activity in pts with WM, including those who relapse after R therapy, with rapid improvement in hgb and slower reduction of IgM levels. Based on the acceptable safety profile in this study and the dose of OFA approved for refractory CLL, the study was amended to increase the OFA dose to 2000 mg and allow a 2nd cycle of therapy for pts who do not attain PR after cycle 1. Accrual to the amended study is ongoing. Disclosures: Furman: GlaxoSmithKline: Consultancy, Speakers Bureau; Genentech: Consultancy, Speakers Bureau; Cephalon, Inc.: Speakers Bureau; Celegene: Consultancy; Calistoga: Consultancy. Off Label Use: Ofatumumab is an investigational anti-CD20 monoclonal antibody, currently under development for the treatment of B-cell malignancies (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, Waldenstroms macroglobulinemia and follicular lymphoma) as well as autoimmune diseases (rheumatoid arthritis and multiple sclerosis). Switzky:GlaxoSmithKline: Employment, Research Funding; Genmab: Employment, Research Funding. Leonard:GlaxoSmithKline: Consultancy. Liao:GSK: Employment. Shah:GlaxoSmithKline: Employment; Genmab: Research Funding. Brownell-Buttich:GlaxoSmithKline: Employment. Lisby:Genmab A/S: Employment. Lin:GlaxoSmithKline: Consultancy, Employment.

High levels of circulating miR-16 in the serum of multiple myeloma (MM) patients are independently associated with longer survival. Although the tumor suppressor function of intracellular miR-16 in MM plasma cells (PCs) has been elucidated, its extracellular role in maintaining a nonsupportive cancer microenvironment has not been fully explored. Here, we show that miR-16 is abundantly released by MM cells through extracellular vesicles (EVs) and that differences in its intracellular expression as associated with chromosome 13 deletion (Del13) are correlated to extracellular miR-16 levels. We also demonstrate that EVs isolated from MM patients and from the conditioned media of MM-PCs carrying Del13 more strongly differentiate circulating monocytes to M2-tumor supportive macrophages (TAMs), compared with MM-PCs without this chromosomal aberration. Mechanistically, our data show that miR-16 directly targets the IKKα/β complex of the NF-κB canonical pathway, which is critical not only in supporting MM cell growth, but also in polarizing macrophages toward an M2 phenotype. By using a miR–15a-16-1–KO mouse model, we found that loss of the miR-16 cluster supports polarization to M2 macrophages. Finally, we demonstrate the therapeutic benefit of miR-16 overexpression in potentiating the anti-MM activity by a proteasome inhibitor in the presence of MM-resident bone marrow TAM.

AbstractObjectivesTo evaluate the safety and efficacy of maintenance therapy with the oral proteasome inhibitor ixazomib in patients with newly diagnosed multiple myeloma (NDMM) not undergoing transplantation.MethodsData were pooled from four NDMM phase I/II studies; patients received induction therapy with once‐ or twice‐weekly ixazomib plus lenalidomide‐dexamethasone (IRd), melphalan‐prednisone (IMP), or cyclophosphamide‐dexamethasone (ICd), followed by single‐agent ixazomib maintenance, given at the last tolerated dose during induction, until disease progression, death, or unacceptable toxicity.ResultsA total of 121 patients achieved stable disease or better after induction (weekly IRd, n = 25; twice‐weekly IRd, n = 18; weekly or twice‐weekly IMP, n = 35; weekly ICd, n = 43) and received ≥ 1 dose of ixazomib maintenance. Grade ≥ 3 drug‐related adverse events occurred in 24% of patients during maintenance; each event was reported in ≤2% of patients. Rates of complete response were 22% after induction and 35% after maintenance. A total of 28 patients (23%) improved their response during maintenance.ConclusionsIxazomib maintenance following ixazomib‐based induction is associated with deepening of responses and a positive safety profile with no cumulative toxicity in patients with NDMM not undergoing transplantation, suggesting that ixazomib is feasible for long‐term administration. Phase III investigation of ixazomib maintenance is ongoing.