Siegel, David S.

Abstract Introduction: Single-agent carfilzomib has shown encouraging activity in patients with relapsed and refractory multiple myeloma who harbor high-risk cytogenetic abnormalities (Jakubowiak et al, Leukemia 2013;27:2351-56). The phase 3 study ASPIRE (NCT01080391; N=792 patients) demonstrated that progression-free survival (PFS) was significantly improved with carfilzomib, lenalidomide, and dexamethasone (KRd), compared with lenalidomide and dexamethasone (Rd) in patients with relapsed multiple myeloma (RMM) (Stewart et al, N Engl J Med 2015;372:142-52). We present a pre-planned subgroup analysis of the efficacy and safety of KRd vs Rd in the ASPIRE study according to baseline cytogenetic risk status. Methods: Adults with RMM (1-3 prior lines of therapy) were eligible. Patients were randomized (1:1) to KRd or Rd. Treatment was administered in 28-day cycles. Patients in the KRd arm received carfilzomib as a 10-minute intravenous infusion on days 1, 2, 8, 9, 15, and 16 (starting dose, 20 mg/m2 on days 1 and 2 of cycle 1; target dose, 27 mg/m2 thereafter) during cycles 1-12; carfilzomib was omitted on days 8 and 9 during cycles 13-18 and was discontinued after 18 cycles. All patients received lenalidomide 25 mg on days 1-21 and dexamethasone 40 mg on days 1, 8, 15, and 22. The primary end point was PFS. Secondary end points included overall survival, overall response rate (ORR), duration of response (DOR), health-related quality of life, and safety. Cytogenetic risk status was assessed using fluorescence in situ hybridization. The high-risk group consisted of patients with the genetic subtype t(4;14) or t(14;16) or with deletion 17p in ≥60% of plasma cells, according to central review of bone marrow samples obtained at study entry. The standard-risk group consisted of all other patients with known baseline cytogenetics. The cutoff value of 60% for the proportion of plasma cells with deletion 17p was used on the basis of recommendations from the International Myeloma Workshop Consensus Panel 2 (Munshi et al. Blood 2011;117:4696-700). Results: A total of 792 patients were randomized to KRd (n=396) or Rd (n=396). In patients with known baseline cytogenetics, baseline cytogenetic risk status was similar between the treatment arms (high-risk: KRd, 24.6%; Rd, 23.4%; standard-risk: KRd, 75.4%; Rd, 76.6%). Efficacy outcomes by cytogenetic risk status are presented in the Table. Median PFS in the high-risk group (n=100) was 23.1 months (95% confidence interval [CI]: 12.5-24.2) for KRd vs 13.9 months (95% CI: 9.5-16.7) for Rd (hazard ratio [HR]: 0.639; 95% CI: 0.369-1.106). Median PFS in the standard-risk group (n=317) was 29.6 months (95% CI: 24.1-not estimable) for KRd vs 19.5 months (95% CI: 14.8-26.0) for Rd (HR: 0.657; 95% CI: 0.480-0.901). ORRs were 79.2% (KRd) vs 59.6% (Rd) in the high-risk group, and 91.2% (KRd) vs 73.5% (Rd) in the standard-risk group. In the high-risk group, 29.2% (KRd) and 5.8% (Rd) of patients achieved a complete response (CR) or better, including 16.7% (KRd) and 3.8% (Rd) with a stringent complete response (sCR). In the standard-risk group, 38.1% (KRd) and 6.5% (Rd) of patients achieved ≥CR, including 15.0% (KRd) and 3.5% (Rd) with an sCR. Median DOR in the high-risk group was 22.2 months for KRd vs 14.9 months for Rd. Median DOR in the standard-risk group was 30.4 months for KRd vs 20.4 months for Rd. The rate of grade ≥3 adverse events was 89.1% (KRd) vs 78.4% (Rd) in the high-risk group, and 85.6% (KRd) vs 84.5% (Rd) in the standard-risk group. Rates of grade ≥3 adverse events of interest (dyspnea, hypertension, acute renal failure, cardiac failure, ischemic heart disease, and peripheral neuropathy) by cytogenetic risk status are presented in the Table. Conclusion: In patients with high-risk cytogenetics, treatment with KRd resulted in a median PFS of nearly 2 years, which was a 9-month improvement relative to that in patients treated with Rd. Treatment with KRd also led to a 10-month improvement in median PFS vs Rd in patients with standard-risk cytogenetics; similar reductions in the risk of progression or death with Kd vs Vd were observed in both cytogenetics risk groups. Treatment with KRd also led to higher response rates, greater response depth, and a longer DOR compared with Rd in patients with high- or standard-risk cytogenetics. KRd had a favorable benefit-risk profile in patients with RMM, irrespective of baseline cytogenetic risk status, and improved outcomes in patients with high-risk disease. Disclosures Fonseca: Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Applied Biosciences: Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Onyx/Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Binding Site: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding. Siegel:Celgene Corporation: Consultancy, Speakers Bureau; Amgen: Speakers Bureau; Takeda: Speakers Bureau; Novartis: Speakers Bureau; Merck: Speakers Bureau. Dimopoulos:Celgene: Honoraria; Onyx: Honoraria; Genesis: Honoraria; Janssen-Cilag: Honoraria; Novartis: Honoraria; Janssen: Honoraria; Amgen: Honoraria. Spicka:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Masszi:Novartis: Consultancy; Janssen-Cilag: Consultancy; BMS: Consultancy; Takeda: Consultancy. Hájek:Janssen-Cilag: Honoraria; Celgene, Merck Sharp & Dohme: Consultancy, Honoraria. Rosiñol:Celgene: Honoraria; Janssen: Honoraria. Mateos:Janssen-Cilag: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Takeda: Consultancy; Onyx: Consultancy. Wang:Celgene: Research Funding. Niesvizky:Celgene: Consultancy, Speakers Bureau. Oriol:Celgene: Consultancy, Speakers Bureau; Janssen: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau. Jakubowiak:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SkylineDx: Membership on an entity's Board of Directors or advisory committees; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi-Aventis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: institutional funding for support of clinical trial conduct, Speakers Bureau; Onyx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi-Aventis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SkylineDx: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Palumbo:Celgene, Millennium Pharmaceuticals, Amgen, Bristol-Myers Squibb, Genmab, Janssen-Cilag, Onyx Pharmaceuticals: Consultancy, Honoraria; Novartis, Sanofi Aventis: Honoraria. Bensinger:Onyx: Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Acetylon: Research Funding; BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millenium: Research Funding. Kukreti:Lundbeck: Honoraria; Ortho: Honoraria; Janssen: Honoraria; Celgene: Honoraria; Amgen: Honoraria. Tonda:Onyx: Employment. Obreja:Amgen Inc: Employment. Moreau:Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen-Cilag: Honoraria, Membership on an entity's Board of Directors or advisory committees; Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees.

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 3031 Background: Treatment-induced peripheral neuropathy (TIPN) can be a debilitating side-effect as well as a therapy-limiting complication in multiple myeloma (MM). Thalidomide (THAL) and bortezomib (BTZ) are two therapies frequently associated with TIPN in MM. Carfilzomib (CFZ) is a novel and highly selective epoxyketone proteasome inhibitor that differs from BTZ both structurally and mechanistically. CFZ overcomes BTZ-resistance in vitro, lacks the off-target activities of BTZ in preclinical studies, and does not cause neurotoxicity in long-term (6–9 month) chronic animal toxicology studies (Kirk et al. Blood, 2008). Single-agent CFZ produces durable responses in relapsed or refractory (R/R) MM without dose-limiting PN. Here we report on the clinical experience with single-agent CFZ in the Ph 2b PX-171-003-A1 trial in patients (pts) with R/R MM and Grade (G) 1/2 PN at study entry. Methods: Pts received CFZ at 20 mg/m2 IV, on Days 1, 2, 8, 9, 15, and 16 in a 28-day cycle (C) for the first C followed by 27 mg/m2 thereafter for up to 12 C. Pts completing 12 C were eligible to enter an extension study. Responses and progression were determined according to the International Myeloma Working Group (IMWG) criteria and were assessed by an Independent Review Committee (IRC). PN data were collected for all pts on study and included neuropathy history, neurological physical exam and PN-related quality of life data (FACT-GOG/NTx v 4.0 scores) collected at screening. Prospective neurological exams and subjective reporting of PN occurred every 2 cycles until study discontinuation to proactively assess for PN. Adverse event (AE) data were also collected, with AEs reported as ‘neuropathy peripheral', ‘neuropathic pain', ‘neuropathy', and ‘peripheral sensory neuropathy' included as PN. AE reports of ‘paraesthesias' and ‘dysesthesias' were counted separately. Results: Of the 266 pts with R/R MM in PX-171-003-A1, 237 (89%) had a history of PN which was attributable to prior anti-myeloma therapy, including THAL (108 pts/41%), BTZ (134 pts/50%), or both BTZ and THAL (17 pts/6.4%). 206 of the 266 (77%) had G1/2 PN at baseline and a median disease duration of 5.9 years. This subset with active PN at baseline had received a median of 5 prior lines of therapy (range 1–20), with a median 13 anti-myeloma agents, and a median of 2 prior BTZ- and 1 prior THAL- containing regimens. Prior therapies included 100% BTZ, and 100% either THAL (77%) or prior lenalidomide (95%). Responses in the subset of pts with baseline PN were nearly identical to those seen in the full study population with an overall response rate (ORR; ≥ partial response [PR]) of 24% and a clinical benefit response rate (CBR; ≥ minimal response [MR]) of 36%. The median duration of response (≥PR) was 7.4 mo (95% CI 5.6–not reached) and median duration of MR was 6.3 months in both the overall and PN-baseline cohorts. OS and TTP data will also be reported. The most common treatment-emergent ≥G3 adverse events regardless of relationship to study drug were primarily hematologic and were as follows: thrombocytopenia (24%), anemia (21%), lymphopenia (11%), pneumonia (9%), neutropenia (9%), fatigue (7%), hypercalcemia (7%), and hyponatremia (6%). Although 77% of pts had G1/2 PN at baseline, new onset PN was infrequent with PN AEs of any grade reported in 31 (15%) pts and G3 PN reported in only 1 (0.4%) pt. New onset or worsening of paraesthesias (6.8%) and dysesthesias (0%) was also infrequent. Conclusions: Analysis of the subset of pts (77%) with active PN (G1/2) in this single-agent Ph 2 trial of CFZ in pts with R/R MM demonstrated that PN has no impact on depth or durability of responses, or on the tolerability of CFZ, in heavily pretreated pts with multiply relapsed and refractory MM. Reports of new or worsening PN were very uncommon, and paraesthesias and dysesthesia were generally infrequent and mild. CFZ can be given to pts with baseline PN with little risk of exacerbation; prolonged therapy is possible in this population. Disclosures: Martin: Celgene: Honoraria; Onyx: Consultancy. Singhal:Celgene: Speakers Bureau; Takeda/Millenium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx: Research Funding. Vij:Onyx: Honoraria. Wang:Celgene: Research Funding; Onyx: Research Funding; Millenium: Research Funding; Novartis: Research Funding. Stewart:Millennium: Consultancy; Celgene: Honoraria. Jagannath:Millenium, OrthoBiotec, Celgene, Merck, Onyx: Honoraria; Imedex, Medicom World Wide, Optum Health Education, PER Group: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Lonial:Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Onyx: Consultancy, Research Funding. Jakubowiak:Millennium Pharmaceuticals, Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria; Centocor Ortho Biotech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Exelixis: 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. Kukreti:Celgene: Honoraria; Roche: Honoraria; Ortho Biotech: Honoraria. Alsina:Millenium: Consultancy, Research Funding; Celgene: Research Funding; Novartis: Consultancy. Zonder:Millenium: Consultancy, Honoraria, Research Funding; Cephalon: Research Funding; Celgene: Honoraria. Wong:Onyx Pharmaceuticals: Employment. Vallone:Onyx Pharmaceuticals: Employment. Chang:Onyx Pharmaceuticals: Employment. Kauffman:Onyx Pharmaceuticals: Employment. Siegel:Millenium: Consultancy, Honoraria; Celgene: Consultancy, Honoraria.

Abstract Abstract 38 INTRODUCTION: Lenalidomide and bortezomib have moved into the management of newly diagnosed multiple myeloma leading to dramatically improved outcomes. As a consequence, the role of upfront autologous peripheral blood stem cell transplant (ASCT) has become more controversial. The ECOG E4A03 clinical trial randomized newly diagnosed MM patients to lenalidomide with high-dose dexamethasone (LD) vs lenalidomide with low-dose dexamethasone (Ld) (Rajkumar et al Lancet Oncol 2010; 11: 29–37). Upon completing four cycles of therapy, pts had the option of ASCT or continuing on the assigned therapy. The purpose of this abstract is to determine the outcome of patients on this trial pursuing early ASCT according to various age-groups. MATERIALS and METHODS: This is a post hoc, retrospective analysis of overall survival within age subgroups stratified by early ASCT status. This is a landmark analysis including only pts surviving the first 4 cycles of therapy. RESULTS: In all three age-groups studied, 1, 2, and 3-year survival probability estimates with ASCT were excellent (Tables 1, 2, and 3). For patients under the age of 65 who survived the first 4 cycles of therapy, overall survival at 3-years was 94% with early ASCT, 78% in pts continuing protocol therapy. Although direct comparison with patients not going to early transplant is not possible because the assignment to early ASCT versus no early ASCT was not randomized, survival with ASCT at 3-years appeared higher. While we attempt to correct for age, the differences may be influenced by other factors such as performance status, comorbidities, response to therapy, etc. The presumption that treatment related mortality (TRM) should be more problematic for older pts undergoing ASCT is addressed by looking at the >65 and >70yo cohorts. In the >65 age group, one-year mortality is similar between the early ASCT population and the no early ASCT population. In the >70 age group, no adverse impact of early ASCT was seen in the first year on overall survival but the sample size is extremely small. In all age groups early ASCT seemed to mitigate some of the survival disadvantage associated with randomization to the LD arm. CONCLUSIONS: This analysis shows that the strategy of lenalidomide plus dexamethasone induction followed by early ASCT has a remarkably good outcome in terms of overall survival in all age groups studied and supports the continued role of early consolidative ASCT in newly diagnosed patients. The risk of early mortality was notably low in the first year in all age groups. The risk of early mortality seems to increase at 2 years for the LD pts not choosing early ASCT and at 3 years for the Ld pts not choosing early ASCT. Selection bias makes it difficult to compare results for pts that chose early ASCT directly to the patients who did not receive early ASCT in this trial. As such, these results emphasize the need for randomized trials investigating the timing of ASCT in myeloma in the era of novel therapy. Disclosures: Siegel: Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Membership on an entity's Board of Directors or advisory committees. Off Label Use: Lenalidomide for front line therapy. Abonour:Celgene: Speakers Bureau; Millennium Pharmaceuticals: Speakers Bureau. Callander:Millennium Pharmaceuticals: Research Funding. Fonseca:Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy, Research Funding; Genzyme: Consultancy; Onyx: Research Funding; Otsuka: Consultancy; Medtronic: Consultancy. Vesole:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Abstract Background: Malignant cells alter metabolism in order to enable their highly anabolic state. In addition to a massive increase in glycolysis, malignant cells frequently become dependent on glutamine to feed the TCA cycle and provide key building blocks for cell growth and proliferation. CB-839 is a first-in-class potent and selective inhibitor of glutaminase (GLS), the first step in glutamine metabolism, that has broad in vitro and in vivo anti-tumor activity in solid and heme malignancies, including multiple myeloma. GLS inhibition with CB-839 induces apoptosis and/or growth arrest in multiple myeloma and lymphoma cell lines and is synergistic with pomalidomide and lenalidomide in vitro and as well as in multiple myeloma xenograft models in vivo. Methods: CX-839-002 is an ongoing Ph1 evaluation of escalating doses of CB-839 in patients with relapsed/refractory multiple myeloma (MM) or non-Hodgkins lymphoma (NHL) with the primary objective of assessing the safety profile and selecting a recommended Phase 2 dose (RP2D). Pharmacokinetics (PK) was monitored on Days 1 and 15. Initially, CB-839 was given three times daily (TID) without food, but based on PK and safety data generated across three Ph1 studies in patients with solid and heme malignancies, the drug is now being given twice daily (BID) with meals. Results: Safety data are available for a total of 14 patients (9 MM, 4 follicular lymphoma, 1 diffuse large B cell lymphoma) that have enrolled to date during the dose escalation (100-400 mg TID and 600 mg BID). The patients have received a median of 7 prior lines of systemic therapy. CB-839 has been well tolerated with only three subjects experiencing a Gr3/4 AEs considered possibly related to study drug and there have been no discontinuations due to AEs. A similar tolerability profile has been observed across three Ph1 studies for CB-839. With a total of 119 pts treated with CB-839 across the three studies, Gr3/4 drug-related AEs have occurred in 16 subjects (13%) and 4.3% of discontinuations were due to AEs. Reversible, asymptomatic elevations in transaminases have been the primary Gr3 AEs, occurring primarily on the TID schedule in 6/59 (10.2%) pts; only one occurred among 60 pts (1.7%) receiving the BID regimen. BID dosing with 600 mg was determined to be the RP2D and combination studies with pomalidomide and dexamethasone have been initiated. The half-life of CB-839 is ~4 hr, exposure increases with dose, and trough concentrations generally remain above the target threshold of 200 ng/mL for patients receiving the RP2D. Six of 8 MM pts that received ≥ 400 mg TID achieved steady state (D15) trough concentrations above the PK target threshold while 0 of 5 pts that received ≤ 250 mg TID achieved the PK threshold. Pharmacodynamic assessment of GLS activity in MM patients was consistent with a broader PK/PD assessment (across all 3 Ph1 studies), which established clear exposure-dependent inhibition of the target in peripheral blood platelets 4 hr after the first dose of CB-839, with >90% inhibition being maintained for most patients at the RP2D. Preliminary efficacy data include confirmed stable disease in 4 of 9 evaluable MM patients. Updated efficacy data and correlative studies on clinical samples will also be presented. The first pt treated with the combination of CB-839 and pomalidomide/dexamethasone (Pd) during dose escalation received 400 mg CB-839 BID, pomalidomide at 4 mg/day (D1-21) and dexamethasone at 40 mg on Days 1, 8, 15 and 22 of each 28-day cycle. This pt had a 71% decreased in urine M-protein and an 83% reduction in serum free light chain after the first 2 cycles of treatment. This pt had 11 prior lines of therapy but not pomalidomide and had two stem cell transplants and was progressing rapidly prior to study entry. The pt has tolerated the combination well and is continuing on study. Conclusions: CB-839 has been well tolerated at and above doses that produced robust inhibition of GLS in blood platelets and in tumors. Dosing BID with food has improved the PK profile and mitigated the frequency and severity of LFT elevations, which was the primary safety signal using TID dosing. Strong preclinical combination data, an excellent clinical safety profile, and initial data with CB-839 combined with Pd provide a strong rationale for continued development of CB-839 this combination in pts with relapsed/refractory multiple myeloma. Disclosures Vogl: Constellation Pharmaceuticals: Research Funding; Calithera Biosciences: Research Funding; Celgene Corporation: Consultancy; Acetylon Pharmaceuticals, Inc.: Research Funding; Millennium Pharmaceuticals: Research Funding; GSK: Research Funding. Younes:Celgene: Honoraria; Curis: Research Funding; Sanofi-Aventis: Honoraria; Seattle Genetics: Honoraria, Research Funding; Novartis: Research Funding; Janssen: Honoraria; Takeda Millenium: Honoraria; Bristol Meyer Squibb: Honoraria; Bayer: Honoraria; Incyte: Honoraria; Johnson and Johnson: Research Funding. Orford:Calithera Biosciences: Employment, Equity Ownership. Bennett:Calithera Biosciences: Employment, Equity Ownership. Siegel:Celgene Corporation: Consultancy, Speakers Bureau; Amgen: Speakers Bureau; Takeda: Speakers Bureau; Novartis: Speakers Bureau; Merck: Speakers Bureau. Berdeja:Curis: Research Funding; Acetylon: Research Funding; Novartis: Research Funding; Janssen: Research Funding; Takeda: Research Funding; BMS: Research Funding; Array: Research Funding; MEI: Research Funding; Abbvie: Research Funding; Celgene: Research Funding; Onyx: Research Funding.

Abstract Introduction Gene Expression Profiling studies have resulted in signatures capable of providing robust prognosis for Multiple Myeloma (MM) patients, such as the EMC92 [SKY92, Kuiper et al. Leukemia 2012]. Recently, data from 4720 MM patients from the HOVON-65/GMMG-HD4, UAMS-TT2, UAMS-TT3, MRC-IX, APEX and IFM trials were employed to assessed the majority of currently identified prognostic markers and their combinations (GEP, FISH, and biochemistry data, [Kuiper et al ASH 2014]). The "SKY92 + ISS" was identified and validated as the statistically most optimal (i.e. most significant and robust) prognostic marker combination for MM patients. The combination of the EMC92 (=SKY92) and ISS prognostic features proves to be a very powerful, unprecedented and straightforward prognostic system. It identifies four prognostic risk classes: low risk (ISS I-SKY92 standard risk (SR)), intermediate-low (ISS II-SKY92 SR), intermediate-high (ISS III-SKY92 SR) and high risk (ISS I-III, SKY92 high risk). Previously, the SKY92 has been validated on the 91 MM cases in the MMGI cohort [Van Beers et al. ASH 2013]. Here we present an extension of that validation with the SKY92 + ISS combination on the 78 MM cases for whom both GEP and ISS is available, by both assessing as the "4 risk group" model defined above, but also a "3 risk group" model (the two intermediate groups combined) as this may be more relevant and useful for clinical application. Materials and Methods A public untreated MM dataset (Multiple Myeloma Genomics Initiative, MMGI) had n=78 cases for which OS, GEP, and ISS were available for analysis. The prognostic markers SKY92 and ISS were applied as proposed [Kuiper et al ASH 2014] to classify cases into the risk categories. Results The risks for the 4 group classification model are shown in Table 1 and Figure 1, and the 3 risk group model is shown in Table 2 and Figure 1. In the 4 group model, the intermediate-low group (SKY92 standard + ISS II) was a small and not significantly different (p=0.79) from the low risk. The intermediate-high group (SKY92 standard + ISS III) was also a small group, with significantly worse outcome compared with the low risk group (p=0.012). Although stratification into four groups was statistically superior in the training and validation data [Kuiper et al ASH 2014] the interpretability benefits from aggregation of the middle two groups [Fig 1 right]. Table 1. Classification results for the four risk groups (Fig 1 left) Risk group n % Median OS HR vs low risk SKY92 High Risk regardless of ISS 19 24 28.4 m 10.8 SKY92 standard risk + ISS-III 10 13 63.0 m 4.1 SKY92 standard risk + ISS-II 16 21 NR (0.8) SKY92 standard risk + ISS-I (low risk) 33 42 NR NA NR= Not Reached at 96 months, HR= hazard ratio Table 2. Classification results for the three risk groups (Fig 1 right) Risk group n % Median OS HR vs low risk SKY92 High Risk regardless of ISS 19 24 28.4 m 10.1 SKY92 standard risk + ISS-II/III 26 34 78.5 m (1.8) SKY92 standard risk + ISS-I 33 42 NR NA NR= Not Reached at 96 months, HR= hazard ratio, () not significant Conclusions By applying the SKY92 + ISS risk stratification model in an independent validation cohort of newly diagnosed Multiple Myeloma patients, besides a high risk group of 19 patients (24%), a group of 33 patients (42%) with superior prognosis could be predicted (SKY92 standard risk and ISS I) that translated into 62% OS at 96 months. The 19 high risk (SKY92 high risk) cases had very poor prognosis (median survival of 28 months). The combination of SKY92 Standard Risk and ISS II and III seems useful for definition of "intermediate risk" although sample size currently is insufficient for significance compared to low risk. The intention is to also perform this validation on the relapsed samples from the MMGI cohort, once OS data has been collected. This validated risk model could play a role in the design of future treatment strategies for high and low risk MM patients. Figure 1. Kaplan Meier curves on the 78 MMGI cases, split into four (left) or three (right) risk groups based on the combination of SKY92 + ISS. Hazard Ratios (HR) are from a Cox proportional Hazards model comparing a particular group to the low risk group. Figure 1. Kaplan Meier curves on the 78 MMGI cases, split into four (left) or three (right) risk groups based on the combination of SKY92 + ISS. Hazard Ratios (HR) are from a Cox proportional Hazards model comparing a particular group to the low risk group. Disclosures van Beers: SkylineDx: Employment. van Vliet:SkylineDx: Employment. de Best:SkylineDx: Employment. Chari:Novartis: Consultancy, Research Funding; Millennium/Takeda: Consultancy, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Biotest: Other: Institutional Research Funding; Array Biopharma: Consultancy, Other: Institutional Research Funding, Research Funding; Onyx: Consultancy, Research Funding. Jagganath:Millennium: Honoraria; Celgene: Honoraria. Jakubowiak:Sanofi-Aventis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: institutional funding for support of clinical trial conduct, Speakers Bureau; SkylineDx: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SkylineDx: 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, Research Funding, Speakers Bureau; Sanofi-Aventis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Kumar:Celgene, Millenium, Sanofi, Skyline, BMS, Onyx, Noxxon,: Other: Consultant, no compensation,; Janssen: Research Funding; AbbVie: Research Funding; Sanofi: Research Funding; Millenium/Takeda: Research Funding; Celgene: Research Funding; Onyx: Research Funding; Skyline, Noxxon: Honoraria. Lebovic:Onyx: Speakers Bureau; Celgene: Speakers Bureau. Lonial:Millennium: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Celgene: Consultancy, Research Funding. Reece:Onyx: Honoraria; Novartis: Honoraria; Millennium: Research Funding; Merck: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; BMS: Research Funding. Richardson:Millennium Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gentium S.p.A.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees. Siegel:Celgene Corporation: Consultancy, Speakers Bureau; Amgen: Speakers Bureau; Takeda: Speakers Bureau; Novartis: Speakers Bureau; Merck: Speakers Bureau. Stewart:SkylineDx: Membership on an entity's Board of Directors or advisory committees. Vij:Onyx: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Millennium: Honoraria, Speakers Bureau; BMS: Consultancy; Takeda: Consultancy, Research Funding; Novartis: Consultancy; Sanofi: Consultancy; Janssen: Consultancy; Merck: Consultancy. Zimmerman:Celgene: Honoraria, Speakers Bureau; Millennium: Honoraria, Speakers Bureau; Onyx: Honoraria; Amgen: Honoraria, Speakers Bureau. Fonseca:Onyx/Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Binding Site: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Applied Biosciences: Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding.

Abstract Abstract 1942 Background: The impact of cytogenetic abnormalities on the response to therapies and survival in patients (pts) with multiple myeloma (MM) has been well established in the literature. Bortezomib (BTZ), either alone or in combination with other agents, has been shown to overcome the adverse impact of several common unfavorable cytogenetic features. In addition, responses with lenalidomide (LEN)/dexamethasone and pomalidomide have also been reported in patients with unfavorable cytogenetic profiles. Carfilzomib (CFZ) is a novel and highly selective epoxyketone proteasome inhibitor which produces durable single-agent activity in pts with R/R MM. The objective of this analysis was to evaluate the influence of cytogenetics in a large Ph 2b study (PX-171-003-A1), with single-agent CFZ in pts with R/R MM. Methods: Of the 266 pts enrolled in the 003-A1 study, 229 pts (86%) were response evaluable and had available metaphase cytogenetics and/or fluorescence in situ hybridization (FISH) analyses for hypodiploidy, chromosome 13 deletions, del 17p13, t(4:14), and t(14;16) chromosomal abnormalities. Metaphase cytogenetic analyses were available for 200 pts (75%) and FISH results were available for 205 pts (77%). All pts received CFZ at 20 mg/m2 IV on days 1, 2, 8, 9, 15, and 16 in a 28-day cycle (C) in C1 followed by 27 mg/m2 in each C thereafter for up to 12 C. Pts who completed 12 C of therapy were eligible to continue CFZ on an extension study. For the analysis, overall response rate was defined as ≥PR by International Myeloma Working Group (IMWG) criteria. Clinical benefit response (CBR; ORR + MR as defined by EBMT criteria) was also assessed. All responses were assessed and confirmed by an Independent Response Review Committee (IRC). Results: The median age in this subpopulation was 64 yrs. Pts must have had disease that was relapsed after ≥2 regimens including BTZ and either thalidomide (THAL) or LEN, and must have been refractory to their most recent regimen. In this heavily pre-treated pt population, pts had received median of 13 prior anti-myeloma drugs and a median of 5 prior regimens. 99.6% of pts had previously received treatment with BTZ, 74% received prior thalidomide, 94% prior lenalidomide, and 74% prior stem cell transplantation. The ORR (≥PR) for the pts with available metaphase cytogenetics and/or FISH analyses was 25% and the CBR (≥MR) was 38%. 71 of 229 pts (31%) had at least one cytogenetic abnormality. Of these, 27/71 (38%) pts had abnormalities detected via metaphase cytogenetics, 24 (34%) pts were detected by FISH and 20 (28%) pts had abnormalities by both methods. The presence of deletion 13 or hypodiploidy by cytogenetics or del17p13, t(4;14), or t(14;16) by FISH did not significantly impact the ORR. Specifically, 30% of pts with ≥1 abnormality responded compared to 23% with none. The CBR was also unaffected at 34% vs. 39% for pts with ≥1 and no abnormalities, respectively. For all pts in this analysis, the median duration of response (DOR) was 8 months (95% CI 6–10). For pts with ≥1 abnormality, the DOR was 7 months (95% CI 4–10) and did not differ significantly from the DOR of 8 months (95% CI 6–not reached) in pts with no abnormalities. A complete breakdown of response categories and time-to-progression (TTP) will also be presented. Conclusions: CFZ demonstrated durable and comparable activity in pts with R/R MM in both the absence or presence of one or more cytogenetic abnormalities including hypodiploidy, chromosome 13 deletions, del 17p13, t(4:14), or t(14;16). Notably, these results are consistent with data obtained in another Ph2 study with CFZ in pts with relapsed MM following 1–3 prior therapies and who had abnormal cytogenetics (PX-171-004). The results of the present study suggest that durable responses to CFZ can be achieved in heavily pretreated patients and responses are not impacted by poor prognostic cytogenetic features. Disclosures: Jakubowiak: Millennium Pharmaceuticals, Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria; Centocor Ortho Biotech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Exelixis: 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. Martin:Celgene: Honoraria; Onyx: Consultancy. Singhal:Celgene: Speakers Bureau; Takeda/Millenium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx : Research Funding. Wang:Celgene: Research Funding; Onyx: Research Funding; Millenium: Research Funding; Novartis: Research Funding. Vij:Onyx: Honoraria. Jagannath:Millenium, OrthoBiotec, Celgene, Merck, Onyx: Honoraria; Imedex, Medicom World Wide, Optum Health Education, PER Group: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Lonial:Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Onyx: Consultancy, Research Funding. Kukreti:Celgene: Honoraria; Roche: Honoraria; Ortho Biotech: Honoraria. Bray:Onyx Pharmaceuticals: Employment. Vallone:Onyx Pharmaceuticals: Employment. Kauffman:Onyx Pharmaceuticals: Employment. Siegel:Millenium: Consultancy, Honoraria; Celgene: Consultancy, Honoraria.

Abstract Abstract 308 Introduction: The Eastern Cooperative Oncology Group (ECOG) has previously reported the superior 1 and 2 year survival of Ld versus LD as initial therapy in newly diagnosed symptomatic multiple myeloma (MM) (Rajkumar et al Lancet Oncol 2010; 11: 29–37). The 1 year and 2 year OS for Ld vs LD were 96% and 85% vs 88% and 78%, (p < 0.01), respectively. This despite higher ORR in LD vs Ld (79% vs 68%; p = 0.008). The difference in OS was predominantly due to early death in the LD group (5% vs 0.5%; p = 0.003). As a result of this analysis, Ld is now considered the standard of care. However, it should be noted that the majority of these deaths occurred in pts > 65. In this analysis, we evaluated the impact of age on dexamethasone dose intensity and OS. Methods: 445 pts were randomly assigned: 223 to LD and 222 to Ld. Pts were analyzed on an intent-to-treat basis for OS. The pts were analyzed by age in 2 groups: < 65 and > 65 (the age corresponding to transplant eligibility outside the US). The pts > 65 were then further subdivided into >70 and > 75 yrs. Results are expressed as OS probability at 1 and 2 years post randomization. In addition, to eliminate the early death ‘penalty’ in the LD group in the original analysis, a landmark analysis was performed at 4 months. Results: Overall Survival Probability: Intent-to Treat Analysis Overall Survival Probability: 4 month Landmark Analysis Conclusions: As previously reported, OS in the trial at 1 and 2 years was superior with Ld. OS was not superior with LD compared with Ld in any age group despite a higher response rate. This was true even when using a landmark analysis to eliminate the 5% early deaths seen in the first 4 months of treatment. We conclude the following: 1) LD is not definitively superior to Ld in any age group; 2) Given the higher toxicity in the absence of a clear survival benefit with LD, Ld remains the best choice for all ages. This analysis confirms the original opinion that low-dose dexamethasone is the standard of care for all newly diagnosed MM pts, regardless of age. Disclosures: Vesole: Millennium Pharmaceuticals: Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Centorcor-Ortho-Biotech: Speakers Bureau. Off Label Use: Lenalidomide for front-line therapy in multiple myeloma. Abonour:Celgene: Speakers Bureau; Millennium Pharmaceuticals: Speakers Bureau. Callander:Millennium Pharmaceuticals: Research Funding. Fonseca:Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy, Research Funding; Genzyme: Consultancy; Onyx: Research Funding; Otsuka: Consultancy; Medtronic: Consultancy; Intellikine: Consultancy. Siegel:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Membership on an entity's Board of Directors or advisory committees.

Abstract Abstract 1954 Background: Carfilzomib (CFZ) is a novel, highly selective epoxyketone proteasome inhibitor that produces potent and sustained proteasome inhibition both in vitro and in vivo. CFZ appears to lack many of the off-target activities frequently associated with bortezomib (BTZ). This lack of off-target activity may account for observed differences in tolerability seen with CFZ including lack of significant neuropathy and minimal neutropenia and diarrhea. To date, single agent CFZ has been evaluated in Ph 1 and 2 studies in >600 patients, and the vast majority of patients treated had relapsed and/or refractory (R/R) MM. In these settings, CFZ has demonstrated durable single-agent activity and was well-tolerated in patients with advanced stage disease with co-morbidities including baseline neuropathy or renal insufficiency. Here we present the results of parallel safety analyses of patients from four Ph 1 and 2 studies with CFZ. Materials and Methods: The present safety analyses were based on data accumulated from patients enrolled in the following trials: PX-171-003 A0 (R/R MM), PX-171-003 A1 (R/R MM), PX-171-004 (relapsed MM), and PX-171-005 (R/R MM with varying degrees of renal function). In all studies, the treatment schedule was based on a 28-day cycle, dosing CFZ QDx2 each week for 3 weeks (Days 1, 2, 8, 9, 15, 16) with 12 days of rest. Doses of CFZ ranged from 15–20 mg/m2 in cycle 1 (005 [15 mg/m2], 003 A0 and A1, 004 [20 mg/m2]). In three studies CFZ was escalated to 27 mg/m2 after the first cycle, as tolerated (003- A1, 004-BTZ naïve subset and 005). In PX-171-005, low-dose dexamethasone was added in the majority of patients. Results: CFZ was well-tolerated by patients across the 4 studies analyzed. The most common treatment-emergent adverse events (AEs) included fatigue, anemia, nausea, dyspnea, and thrombocytopenia. Detailed descriptions of the incidence of treatment-related AEs (all Grades (G) in ≥25% of pts; ≥G3 in ≥5% of pts) across studies are presented in the table. Peripheral neuropathy (PN) occurred infrequently across all 4 studies (N= 517), with only 20 patients (3.9%) experiencing PN of any G and only 2 patients (0.4%) with G3 PN. Febrile neutropenia was likewise uncommon, occurring in only 3 patients (0.6%). Serious treatment emergent AEs (SAEs) occurring in ≥1% of patients and considered possibly/probably related to study drug across all 4 studies included: pneumonia (3.5%), congestive cardiac failure (2.5%), acute renal failure (1.7%), pyrexia (1.2%), and dyspnea (1%). Conclusions: Despite a substantial disease burden present in the patient populations described here, CFZ was well-tolerated by patients with MM across all studies examined. The excellent safety/tolerability profile of CFZ has permitted prolonged administration (in some cases over 24 mos of continuous therapy including extension study) with minimal dose modifications or discontinuations due to toxicity. The low levels of neuropathy seen with CFZ make this agent a potentially important treatment option for patients with pre-existing neuropathy from either underlying disease or prior neuropathic anti-myeloma therapy. Disclosures: Singhal: Celgene: Speakers Bureau; Takeda/Millenium: Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Onyx: Research Funding. Siegel:Millenium: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Martin:Celgene: Honoraria; Onyx: Consultancy. Vij:Onyx: Honoraria. Wang:Celgene: Research Funding; Onyx: Research Funding; Millenium: Research Funding; Novartis: Research Funding. Jakubowiak:Millennium Pharmaceuticals, Inc.: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Celgene: Consultancy, Honoraria; Centocor Ortho Biotec: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Exelixis: 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. Lonial:Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Onyx: Consultancy, Research Funding. Kukreti:Celgene: Honoraria; Roche: Honoraria; Ortho Biotech: Honoraria. Zonder:Millenium: Consultancy, Honoraria, Research Funding; Cephalon: Research Funding; Celgene: Honoraria. Wong:Onyx Pharmaceuticals: Employment. McCulloch:Onyx Pharmaceuticals: Employment. Kauffman:Onyx Pharmaceuticals: Employment. Niesvizky:Celgene: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millenium: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Onyx: Consultancy, Research Funding. Stewart:Millennium: Consultancy; Celgene: Honoraria. Jagannath:Millenium, OrthoBiotec, Celgene, Merck, Onyx: Honoraria; Imedex, Medicom World Wide, Optum Health Education, PER Group: Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau.

Abstract Abstract 303 Background: Carfilzomib (CFZ) is a novel proteasome inhibitor that binds its target selectively and irreversibly, resulting in greater and more sustained proteasomal inhibition compared to BTZ (Demo et al, Cancer Res 2007). CFZ overcomes BTZ-resistance in vitro (Kuhn et al, Blood 2007) and in a previous Phase 2 study (PX-171-003), single-agent CFZ achieved durable responses and maintained disease control [e.g. ≥ Stable Disease (SD)] in patients with progressive multiple myeloma (MM) despite treatment with essentially all available agents. PX-171-004 is an ongoing Phase 2 study of CFZ monotherapy in MM patients with relapsed or refractory disease following 1–3 prior therapies. Here we report updated data for the BTZ-treated cohort. Methods: Patients with relapsed or refractory (defined as < 25% response or disease progression during therapy) MM were enrolled and stratified based on prior BTZ exposure (e.g. BTZ-naïve and BTZ-treated). For the BTZ-treated cohort, tolerability and response to prior BTZ [≥ Minor Response (MR)] was not required. CFZ 20 mg/m2 IV was administered on Days 1, 2, 8, 9, 15 and 16 every 28 days, for up to 12 cycles. The primary endpoint was Overall Response Rate (ORR) [≥ Partial Response (PR)] by IMWG criteria. Secondary endpoints included Clinical Benefit Response (CBR = ORR + MR) and safety. Results: Thirty-five BTZ-treated patients were enrolled. Six (17%) patients had previously received BTZ exclusively as a single agent, 15 (43%) received BTZ as part of a chemotherapy combination and 10 (29%) received BTZ as part of a stem cell transplant (SCT) regimen. An additional 4 (11%) received BTZ in a chemotherapy combination as well as part of a separate transplant regimen. Other prior therapies included alkylators (89%), SCT (81%), thalidomide (69%), lenalidomide (37%), and anthracyclines (31%). Six (17%) patients had disease refractory to BTZ and 9 (26%) additional patients had discontinued BTZ due to toxicities. At baseline, 19 (54 %) patients had an ECOG score ≥ 1, 17 (49%) patients had neuropathy of Grade ≥ 1, 9 (26%) patients had impaired renal function (CrCl <60 mL/min) and 9 (26%) had diabetes. The median time since diagnosis was 3.6 years (range 1.2–13.2). To date, the mean number of CFZ doses administered was 29.3 (∼5 four-week cycles; range 4–72 doses, 0.7–12 cycles). Thirty-three patients who initiated therapy were evaluable for response per protocol. The ORR was 18% (6/33), including 1 CR and 5 PRs. An additional 4 (12%) patients had MR (CBR= 30%) and 13 (39%) had SD for ≥ 6 weeks. For evaluable patients who were either refractory or intolerant to their prior BTZ therapy, responses to CFZ included 1 PR and 1 MR and 8 SDs. The most common adverse events (AEs) (≥ 30% patients) were primarily Grades 1/2 and included fatigue (57%), nausea (54%), vomiting (37%), dyspnea (34%), diarrhea (34%), anemia (31%), increased creatinine (31%) and upper respiratory tract infection (31%). Grade 3/4 AEs occurring in ≥ 10% of patients were anemia (14.3%) and neutropenia (11.4%). There were no reports of febrile neutropenia. Dose modifications were rarely required. Peripheral neuropathy (PN) was uncommon (4 patients, 11%); only 1 patient had a Grade 3 event that lasted < 36 hours and did not result in missed doses or dose modification. None of the 9 patients with baseline renal impairment were discontinued for renal AEs. To date, 6 (17%) patients have completed the full 12-cycle protocol at the initial dose and schedule, 6 (17%) remain on study and 1 patient has received > 19 cycles on a recently initiated extended treatment protocol. Conclusions: In a BTZ-exposed population that includes BTZ treatment failures and significant comorbidities (e.g. diabetes, renal insufficiency, etc), the 18% ORR (CBR 30%) is notable for this steroid- and anthracycline-sparing regimen. Single-agent CFZ is well tolerated, even in patients with renal insufficiency, and both myelosuppression and PN are uncommon. These data support the continuing evaluation of CFZ as a safe and effective treatment option in MM. Disclosures: Siegel: 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. Wang:Proteolix, Inc.: Research Funding. Stewart:Genzyme, Celgene, Millenium, Proteolix: Honoraria; Takeda, Millenium: Research Funding; Takeda-Millenium, Celgene, Novartis, Amgen: Consultancy. Kukreti:Celgene: Honoraria. Jakubowiak:Millennium Pharmaceuticals, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Centocor Ortho Biotech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Exelixis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers-Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Jagannath:Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. McDonagh:Proteolix: Research Funding. Belch:Ortho Biotech: Honoraria, Research Funding. Bahlis:Celgene: Honoraria, Speakers Bureau; Ortho Biotech: Honoraria, Speakers Bureau. Le:Proteolix, Inc.: Employment. Kunkel:Proteolix: Consultancy, Employment. Bennett:Proteolix: Employment. Kauffman:Proteolix, Inc.: Employment. Vij:Proteolix, Inc.: Consultancy, Research Funding.