Stewart, A. Keith

Abstract Abstract 2834 Poster Board II-810 Background: Monoclonal gammopathy of undetermined significance (MGUS) results arises from a clonal proliferation of differentiated plasma cells and is a necessary precursor to development of multiple myeloma and some other B cell malignancies. Despite a high incidence in the general population (1-2% of adults in the 6th and 7th decades) and increased relative risk for later malignancy, there are few reports about the clinical course and prognosis of MGUS in long-term immunosuppressed patients. We aimed to evaluate the significance of MGUS in patients undergoing solid transplants in terms of clinical outcomes and rate of transformation to secondary B cell malignancy. Material and methods: We reviewed the medical records of 1493 patients on which kidney (living donor related, living donor-unrelated and deceased donor), liver and pancreatic transplants were performed at Mayo Clinic Arizona, between January 1, 1999 and July 31, 2009 to determine the incidence of MGUS and to further evaluate long-term follow up. At MCA patients are routinely screened using SPEP and for those where an M-spike is detected or suspected immunofixation is required for confirmation. MGUS was defined as previously reported. Patients who had anemia unrelated to their PCD were included. Statistical Methods: Patients were observed until death or, for those still alive, until July 2009. The major goal of the study was to assess the impact of MGUS on transplant outcomes and progression to active myeloma or related disorders. Patients who did not experience progression were censored at the time of last follow-up. Nominal variables were compared using Fisher's exact test. A two-tailed P value less than .05 was considered significant. Results In this series, SPEP was performed in 1199 out of 1593 cases (75%) before transplantation. The most common abnormalities detected by SPEP included a normal pattern (70%), polyclonal pattern (16.8%), hypoalbuminemia (8%), hypogammaglobulinemia (2.4%) and the presence of M spike (2.8%). Immunofixation revealed the presence of a monoclonal immunoglobulin in 34 patients: IgG 30 cases (88%), IgM in 2 (6%) and biclonal disease in 2 (6%). The median age at diagnosis of MGUS was 60 years (range, 46 to 84 years), and included 63.7% of males. Clinical characteristics of the MGUS cases are seen in Table 1. Two MGUS patients were diagnosed only after the transplant was performed (338 and 1082 days respectively). There was no association between post-transplant lymphoproliferative (PTLPD) and MGUS and even when some MGUS patients died (7/34, 20%) death was not associated with progression of the monoclonal clone or development of a PTLPD or other malignancy. MGUS does not impact transplant outcomes. PTLPD disorders developed in 6 cases and none was associated with a MGUS. After a median of 88 months no MGUS patient developed transformation to active myeloma or a related disorder. Overall survival after transplantation was not significantly different among MGUS and Non- MGUS cases (6.48 vs 8.36 years p>0.05). Discussion Despite the frequency of MGUS in the general population there are few studies which have assessed MGUS in solid organ transplant patients. An increased incidence of monoclonal gammopathy in patients with autoimmune disease and in older non-transplant populations suggests that impaired immunity might lead to development of MGUS and later monoclonal B-cell malignancies. Interestingly, we identified two cases where MGUS appeared after transplant. In this series, we report on the incidence and follow/up of MGUS in patients screened before transplantation. The primary outcome for transplant recipients is unaffected by the presence of MGUS and incidence is in accordance with the expected frequency (2.8%). Patients with MGUS do not appear to be at risk for progression due to chronic immunosuppression. Testing for MGUS before transplantation is not cost-efficient and therefore would not be recommended. To our knowledge this is the largest series of MGUS and transplant outcome yet reported. Disclosures: Stewart: Takeda-Millenium, Celgene, Novartis, Amgen: Consultancy; Takeda, Millenium: Research Funding; Genzyme, Celgene, Millenium, Proteolix: Honoraria.

Abstract Abstract 1876 Poster Board I-901 Background: Multiple Myeloma (MM) remains incurable in spite of new effective agents and combination regimens. SRC family kinases (SFK) are potential targets for therapy in MM: Hck, Fyn and Lyn are implicated in IL6-induced proliferation. Dasatinib is a potent inhibitor of not only BCR-ABL, but also SFK, c-KIT, PDGFRb, and EPHA. In myeloma and endothelial cells (ECs) isolated from MM patients (pts), dasatinib blocked proliferation, survival, adhesion, migration, and angiogenic potential, through a combined targeting of PDGFRβ as well as VEGF-triggered phosphorylation of SRC. Lenalidomide has clinical efficacy in the treatment of multiple myeloma (MM) as a single agent and in combination with dexamethasone. The combination of dasatinib, lenalidomide and dexamethasone exhibits synergistic inhibition of MMIS cells. Methods: The primary objective of this Phase I, multicenter, open-label, non-randomized study was to determine the maximum tolerated dose (MTD) of the combination of dasatinib, with lenalidomide and dexamethasone in pts with relapsed or refractory (RR) MM. Secondary objectives were to assess the tolerability of the combination, to establish the dose for future clinical investigations, and to assess the efficacy by International Uniform Response and EBMT Criteria. Pts ≥18 years with confirmed RR MM, measurable disease (at least 1 g/dL for IgG or 0.5 g/dL for IgA in serum or urinary excretion of 200 mg monoclonal light chain/24 hours), and at least one prior treatment were enrolled sequentially into increasing dose cohorts (using a 3+3 design). Pts received oral dasatinib daily on a continuous schedule, oral lenalidomide daily for 21 days, and oral dexamethasone 40 mg/day (Days 1, 8, 15, and 22). Cycles were repeated every 28 days. Dose-limiting toxicities (DLTs) were assessed in the first cycle. If there was no DLT, dose escalation continued to MTD, followed by an expansion phase of the established dose. Results: Enrollment is ongoing. 16 pts (6 M, 10 F; median age 70.5 years, range 51–80) were treated in cohorts 1, 2, 3 and 4; MTD has not been established (as by July 2009). The median number of prior lines of therapy was 3 (range 1–6). Seven pts had prior autologous stem cell transplantation; 8 pts had prior thalidomide, 4 prior lenalidomide and 3 pts both. Baseline β2 microglobulin levels of >3.5mg/L were reported in 4 pts. The most common (310%) treatment related adverse events (AEs) diarrhea 6 (38%); nausea 4 (25%); constipation 2 (13%); stomatitis 2 (13%); asthenia 3 (19%); weight decrease 5 (31%); dyspnea 2 (13%); rash 2 (13%); vertigo 2 (13%); insomnia 2 (13%). The most common grade 3 / 4 hematologic AEs included neutropenia 6 (38%), anemia 4 (25%) and thrombocytopenia 3 (19%). Two DLTs were identified in cohorts 1 and 4: 1 pt had 2 point decline in ECOG Performance Status and other pt had a drug interruption > 15 days due to nausea and vomiting, respectively. Six out of 16 pts discontinued treatment: 1 due to death in first cycle (D19); 3 for AEs (2 study drug related and 1 unrelated), 1 withdrawal of consent, 1 following maximal clinical benefit (minor response) after 12+ cycles. As of July 2009, 10 pts remain on treatment, with a median duration of treatment of 4.2 months (range 0.6–12). Responses were observed in 13 pts: 8 partial responses (PR), and 5 minor responses (MR). 1 pt had stable disease (SD) and 2 pts were not evaluable (1 pts died before completion of cycle 1 and other pt was too early for assessment). Conclusion: Dasatinib in combination with lenalidomide and dexamethasone is well tolerated and preliminary activity has been observed. Disclosures: Facon: Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen Cilag: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees. Stewart:Takeda-Millenium, Celgene, Novartis, Amgen: Consultancy; Takeda, Millenium: Research Funding; Genzyme, Celgene, Millenium, Proteolix: Honoraria. Garzon:BMS: Employment. Bleickardt:BMS: Employment. Gialelis:BMS: Employment. Tuozzoli:BMS: Employment. Derreumaux:BMS: Employment. Sonneveld:Janssen-Cilag: Honoraria.

Abstract Abstract 302 Background: Carfilzomib (CFZ) is a proteasome inhibitor with unique target selectivity and an irreversible binding mechanism that results in sustained proteasome inhibition. In preclinical studies, CFZ lacks non-proteasome off-target activities associated with bortezomib (BTZ) (Kapur et al, Blood 2008). This may account for observed differences in tolerability with CFZ (e.g. minimal neuropathy and myelosuppression), permitting consecutive day dosing and treatment over an extended period of time. We previously observed higher response rates in multiple myeloma (MM) patients without prior BTZ exposure (BTZ-naïve) compared to those with relapsed disease following BTZ therapy (BTZ-treated). Here we present updated data on the BTZ-naïve cohort from PX-171-004, an ongoing Phase 2 study of single-agent CFZ in MM patients with relapsed or refractory disease following 1–3 prior therapies. Methods: Patients with relapsed or refractory (e.g, < 25% response or disease progression during last treatment) MM were enrolled and stratified into two cohorts: BTZ-naïve and BTZ-treated. 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 [≥ Partial Response (PR)] per International Uniform Response Criteria for Multiple Myeloma. Secondary endpoints included Clinical Benefit Response [CBR = ORR + Minor Reponse (MR)] and safety. Results: Fifty-seven BTZ-naive patients have been enrolled and 56 subjects have received at least one dose of CFZ. Prior therapies included alkylators (81%), stem cell transplant (SCT) (77%), thalidomide (THAL) (67%), lenalidomide (LEN) (42%), and anthracyclines (23%). Ten (18%) patients had received both LEN and THAL and 18 (32%) patients were refractory to their most recent regimen prior to study entry. At baseline, 30 (53%) patients had an ECOG score ≥ 1, 21 (37%) had neuropathy Grade ≥ 1, 12 (21%) had impaired renal function (CrCl < 60 mL/min) and 10 (18%) had diabetes. The mean time from diagnosis was 4 years (range 0.7–24). To date, the mean number of CFZ doses administered was 29.2 (∼5 four-week cycles; range 2–72 doses, 1–12 cycles). Fifty-one patients initiated therapy and were evaluable for response per protocol. The ORR was 45% (23/51 patients) and included 1 CR, 4 VGPR and 18 PR. An additional 9 (18%) patients had MR and 10 (20%) had stable disease (SD) for ≥ 6 weeks. The most common (>25%) adverse events (AEs) were fatigue (59%), nausea (41%), dyspnea (36%), and anemia (29%), and were primarily ≤ Grade 2. Grade 3/4 AEs occurring in ≥ 5% of patients were thrombocytopenia (9%), fatigue (9%), neutropenia (7%), lymphopenia (7%), anemia (5%), pneumonia (5%) and hyperglycemia (5%). One (1.7%) patient had febrile neutropenia. Dose modifications were rarely required. Peripheral neuropathy (PN) of any grade was infrequent (7 patients, 12%) with a single case of Grade 3 PN (2%) in a pt with a history of THAL-induced PN that lasted 41 days. The CFZ dose was reduced and the event resolved to Grade 1 while on CFZ and prior to study discontinuation. Of the12 patients with impaired renal function at baseline, none required dose modifications due to renal AE. Overall, 5 patients have completed the full 12-cycle protocol and another 5 (9%) have completed ≥ 9 cycles; 17 patients (30%) are continuing on study. Conclusions: The 45% ORR (CBR 63%) is noteworthy for a single-agent regimen in patients with tumor progression despite therapy with novel combinations. CFZ can be safely administered to patients with significant comorbidities (e.g. peripheral neuropathy, leukopenia, renal dysfunction, diabetes) when other anti-myeloma agents may not be well tolerated. Enrollment to PX-171-004 is continuing and, based on the safety profile, subjects are now permitted to dose escalate to 27 mg/m2. Disclosures: Wang: Proteolix: Honoraria, Research Funding. Off Label Use: testing testing. 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. 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. Kukreti:Celgene: Honoraria. Bahlis:Celgene: Honoraria, Speakers Bureau; Ortho Biotech: Honoraria, Speakers Bureau. McDonagh:Proteolix: Research Funding. Belch:Ortho Biotech: Honoraria, Research Funding. Le:Proteolix, Inc.: Employment. Bennett:Proteolix: Employment. Kunkel:Proteolix: Consultancy, Employment. Kauffman:Proteolix, Inc.: Employment. Vij:Proteolix, Inc.: Consultancy, Research Funding.

Abstract Abstract 2877 Poster Board II-853 Background and Objective: In newly diagnosed multiple myeloma (MM) patients, treatment with lenalidomide plus high-dose dexamethasone (RD) was superior to high-dose dexamethasone in terms of both response rates and 1-year progression-free survival (PFS) (Zonder JA et al, Blood 2007;110:77). Preliminary results suggest that the combination lenalidomide plus low-dose dexamethasone (Rd) compared to the RD regimen yields significantly better 2-year overall survival (OS) (Rajkumar SV et al, J Clin Oncol 2008;26:8504). The combination of melphalan, prednisone, and lenalidomide (MPR) has been investigated in a phase I/II study showing promising results (Palumbo A et al, J Clin Oncol 2007; 25:4459-4465). The goal of this case –control study was to compare the efficacy and the toxicity of the lenalidomide/dexamethasone (len/dex) combination vs MPR as primary therapy for newly diagnosed elderly MM patients, to determine the additive value of melphalan compared to a regimen of lenalidomide plus corticosteroid. Patients and methods: Data from 51 newly diagnosed MM patients enrolled in Italy in a phase I/II dose-escalating trial, from January to October 2005, with MPR, were analyzed. For comparison of their outcome, 37 patients were identified among newly diagnosed patients seen at the Mayo Clinic from March 2005 to December 2008 who received len/dex as primary therapy and were enrolled in phase II or III trials. Patients treated with MPR received 9 monthly cycles of oral melphalan (doses ranging from 0.18 to 0.25 mg/kg on days 1-4), prednisone (2 mg/kg on days 1-4) and lenalidomide (doses ranging from 5 to 10 mg/day on days 1-21). After 9 cycles, patients started maintenance with lenalidomide alone (10 mg, days 1-21) until relapse or progression. Patients treated with len/dex received oral lenalidomide (25 mg/day, days 1-21) plus dexamethasone, either at low-dose (n=17) (40 mg orally days 1, 8, 15, 22) or at high-dose (n=21) (40 mg orally on days 1-4, 9-12, and 17-20). Treatment was continued until progression, relapse or unacceptable toxicity, or could be stopped at the physician's discretion. Patients (n=13) were allowed to receive transplant if they wished and were deemed eligible. Outcome was analyzed on an intention-to-treat basis. The Chi-square or the rank sum tests were used to compare variables. Time-to-event analysis was performed using the Kaplan-Meier method and comparisons were determined by the log-rank test and the Cox proportional hazards model. Results: On intention-to-treat analysis, 15.7% versus 23.7% patients, respectively in the MPR and in the len/dex group, (p=0.342) achieved a complete response, and 43.2% vs 47.4%, (p=0.691) achieved at least a very good partial response. Time-to-progression (TTP) (median: 24.7 vs 27.5 in MPR and len/dex groups, respectively; HR 1.04; 95% CI 0.55-1.98; p=0.903), PFS (median: 24.7 vs 27.5 in MPR and len/dex groups, respectively; HR 1.03; 95% CI 0.55-1.92; p=0.926) and OS (2-year OS: 86.2% in MPR group vs 89.1% in len/dex, HR 0.86; 95% CI 0.38-1.98; p=0.730) were not significantly different between the 2 groups. No significant differences in TTP, PFS and OS were reported when MPR patients were compared with the subgroup of patients treated with low-dose dexamethasone plus lenalidomide. Similar results were found when the analysis was restricted to MPR patients and len/dex pair mates receiving lenalidomide plus low/dose dexamethasone, matched according to age and sex, and who did not received transplant. The toxicity profile was different in the two groups. Hematologic grade 3-4 toxicities were more common with MPR compared with len/dex, in particular neutropenia (66.7% vs 21.1%, p < 0.001) and thrombocytopenia (31.4% vs 2.6%, p < 0.001), respectively. Grade 3-4 gastrointestinal events (13.2% vs 2.0%, p= 0.080), thrombotic events (13.2 vs 5.9, p= 0.279) and fatigue (10.5% vs 3.9%, p= 0.395) were more common with len/dex compared with MPR. Conclusion: Results of this case-control study show that both MPR and Rd are efficacious regimens for elderly MM patients. Data need however to be carefully evaluated and randomized control trials are needed to confirm these results. Disclosures: Off Label Use: research drug in combination to standard of care. Kumar:celgene: Research Funding; millenium: Research Funding; bayer: Research Funding; novartis: Research Funding; genzyme: Research Funding. Dispenzieri:celgene: Research Funding. Gertz:celgene: Honoraria; genzyme: Honoraria; millenium: Honoraria; amgen: Honoraria. Lacy:celgene: Research Funding. Musto:celgene: Honoraria. Fonseca:medtronic: Consultancy; genzyme: Consultancy; celgene: Consultancy; amgen: Consultancy; BMS: Consultancy; otsuka: Consultancy. Petrucci:celgene: Honoraria; Janssen Cilag: Honoraria. Greipp:celgene: Research Funding. Boccadoro:jansen Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; pharmion: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Palumbo:Janssen-Cilag: Honoraria; Celgene: Honoraria.

Abstract Abstract 2865 Poster Board II-841 BACKGROUND: The ubiquitin-proteasome pathway, which has been shown to be an essential cellular degradative system in myeloma cells, can also regulate bone formation through its effects on osteoblast differentiation. Retrospective analysis of variation of ALP during treatment with bortezomib indicates a close correlation between myeloma response and serum ALP levels which multiple studies have shown to be of bone origin. To determine if this effect is a class effect of proteasome inhibitors (PIs), this retrospective study analyzed variation of ALP in relationship to myeloma response during treatment with carfilzomib, the first in a new class of selective epoxyketone PIs that has demonstrated encouraging safety and efficacy in two phase 2 studies of relapsed or refractory myeloma patients. METHODS: Retrospective analysis of serum ALP was performed on relapsed or refractory myeloma patients enrolled on two phase 2 studies (PX-171-003 and PX- 171-004) evaluating the safety and efficacy of single agent carfilzomib. We analyzed data from 38 patients in the first cohort of the PX-171-003 study, a relapsed and refractory myeloma trial for patients who have received ≥ 3 prior therapies including bortezomib and an IMiD and 29 patients in PX-171-004, a relapsed or refractory myeloma trial that included bortezomib naïve patients. All patients received 20 mg/m2 of carfilzomib on Days 1, 2, 8, 9, 15, and 16 of a 28-day cycle. RESULTS: Seventy-seven patients were enrolled. The median age was 63 years with a median time since diagnosis of 4.6 years, 52% were male, 84.% had relapsed after autologous transplants, 82.% were previously exposed to bortezomib, and 92% were previously exposed to an IMiD. Sixty seven patients with ALP data were evaluable for response. In PX-171-003 the ORR (≥PR) was 18% and the clinical benefit response (CBR; ≥MR) was 26%, while in PX-171-004 the ORR was 35.5% overall and 57% in bortezomib naive patients. ALP increment from baseline, which was most evident during the second cycle of treatment, was statistically different in patients who achieved ≥VGPR compared to all others on Days 1 (P=0.0049) and 8 (P=0.006) of Cycle 2. In all patients achieving a VGPR or better, ALP increased more than 15 units per liter at Cycle 2 Day 1 over baseline An ALP increase over the same period of time was seen in 26 %, 13%, and 11% of patients achieving PR, MR, and SD, respectively. None of the patients with progressive disease exhibited a similar increase. Our study indicates that response first assessed on Day 15 of Cycle 1 parallels the ALP elevation which returned to baseline levels at the end of Cycle 3. CONCLUSIONS: This retrospective analysis on a subset of patients in these ongoing phase 2 studies of single agent carfilzomib in relapsed or refractory multiple myeloma suggests that elevation in ALP may be associated with best response. Taken with previous publications describing bortezomib treatment, these results suggest that this specific anabolic bone phenomenon could be a class effect of proteasome inhibitors. These phase 2 studies are ongoing with a higher dose of carfilzomib (27 mg/m2) being evaluated. The data from this small subset analysis suggests that further exploration of this relationship is warranted. Disclosures: Zangari: Milllennium: Honoraria, Research Funding; Novartis: Research Funding; Celgene: Honoraria; OrthoBiotech: Honoraria; Optum Health: Honoraria; Educational Concepts Group, LLC: Membership on an entity's Board of Directors or advisory committees. Vij:Proteolix: Consultancy, Research Funding. Jagannath:Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria; Merck: Honoraria. 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. Stewart:Millennium: Consultancy, Research Funding; Proteolix: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Honoraria. Wang:Proteolix: Honoraria, Research Funding. Belch:Ortho Biotech: Honoraria, Research Funding. 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. Trudel:Celgene: Honoraria, Speakers Bureau; Ortho Biotech: Honoraria. Bahlis:Celgene: Honoraria, Speakers Bureau; Ortho Biotech: Honoraria, Speakers Bureau. Lonial:Celgene: Consultancy; Millennium: Consultancy, Research Funding; BMS: Consultancy; Novartis: Consultancy; Gloucester: Research Funding. Singhal:Celgene: Speakers Bureau; Millennium: Speakers Bureau.

Abstract Abstract 2868 Poster Board II-844 Background and Objective: In newly diagnosed multiple myeloma (MM), the combination of lenalidomide plus high-dose dexamethasone (RD) is superior to high-dose dexamethasone (Zonder JA et al, Blood 2007;110:77). Preliminary results show that lenalidomide plus low-dose dexamethasone (Rd) has better 2-year overall survival (OS) compared with RD (Rajkumar SV et al, J Clin Oncol 2008;26:8504). The addition of clarithromycin (Biaxin) to lenalidomide and low-dose dexamethasone (BiRd) has been investigated in a phase II study, demonstrating a high response rate and 2-year OS (Niesvizky R at al, Blood 2008;111:1101-1109). However, the additive value of clarithromycin is not known. No randomized trials have compared Rd versus BiRd, none are planned. The objective of this case–matched study was to compare the efficacy and the toxicity of BiRd vs Rd as initial therapy for newly diagnosed MM. Patients and methods: Data from 72 newly diagnosed MM patients treated at the New York Presbyterian Hospital–Cornell Medical Center, from December 2004 to December 2006, with BiRD, were analyzed. For comparison, an equal number of pair mates were selected among newly diagnosed patients seen at the Mayo Clinic who received Rd, from March 2005 to December 2008. Case matching was performed with respect to age, gender, and transplant status. Patients treated with BiRd received oral lenalidomide (25 mg/day, days 3-21 of cycle 1; days 1-21 of subsequent cycles); dexamethasone (40 mg days 1, 2, 3, 8, 15, 22 of cycle 1; days 1, 8, 15, and 22 of each subsequent cycle); clarithromycin (500 mg twice daily, from day 2 of cycle 1). Patients treated with Rd received oral lenalidomide (25 mg/day, days 1-21) plus low-dose dexamethasone (40 mg days 1, 8, 15, 22). In both groups patients were allowed to discontinue treatment to pursue transplant, but treatment until progression, relapse or unacceptable toxicity was permitted at the physician's discretion. Outcome was analyzed on an intention-to-treat basis. The Chi-square or the rank sum tests were used to compare variables. Time-to-event analysis was performed using the Kaplan-Meier method; comparisons were determined by the log-rank test and the Cox proportional hazards model. Results: Median duration of treatment was 11.8 months in the BiRd group vs 6 months in the Rd group. On intention-to-treat analysis, complete response was significantly higher with BiRd compared to Rd (45.8% vs 13.9%, respectively, p<0.001); similarly very good partial response (VGPR) or better was higher with BiRd (73.6% vs 33.3%, p<0.001). Rates of VGPR or better, after 6 months and 1 year of therapy, were significantly higher in BiRd patients. Both time-to-progression (TTP) (median 48.3 months vs 27.5 months; HR 0.51; 95% CI 0.25-1.06; p=0.071) and PFS (median 48.3 months vs 27.5 months, HR 0.50; 95% CI 0.25-0.98; p=0.044) were higher with BiRd. Median time to next treatment (TTNT) was not reached in BiRd group compared to 29.9 months in Rd patients (HR 0.37 95% CI 0.20-0.66, p<0.001). There was a trend toward better OS with BiRd, (3-year OS: 89.7% vs 73.0%), but the difference was not statistically significant (HR 0.48; 95% CI 0.17-1.37; p=0.170). Thirty-two patients in each group received transplant; median time to transplant was longer in BiRd group (13.5 vs 5.9 months). Results of survival, for patients who received transplant and patients who did not, were similar to those of the total population. On subset analysis, among patients presenting with International Staging System (ISS) stage I/II at diagnosis, TTP, PFS and TTNT were significantly longer in BiRd patients; no significant differences were found among patients with ISS stage III. Main grade 3-4 toxicities of BiRd were hematological, in particular thrombocytopenia (23.6% vs 8.3%, p=0.012); rate of neutropenia was similar between the 2 groups (19.4% vs 16.7%, p=0.665). Infections (16.7% vs 9.7%, p=0.218) and dermatological toxicity (12.5% vs 4.2%, p=0.129) were higher in patients who received Rd. Rate of venous thromboembolism was similar in the 2 groups (9.7% vs 12.5%, respectively in Rd and BiRd patients, p=0.596). Conclusion: Results of this case-control analysis suggest superiority of BiRd in terms of response rate and survival, compared with Rd, and suggest that there may be a significant additive value when clarithromycin is added to Rd. These data indicate the need for randomized prospective phase III studies to evaluate BiRd versus Rd in the treatment of MM. Disclosures: Off Label Use: research drug in combination to standard of care. Kumar:celgene: Research Funding; millenium: Research Funding; bayer: Research Funding; novartis: Research Funding; genzyme: Research Funding. Mark:celgene: Research Funding. Dispenzieri:celgene: Research Funding. Gertz:celgene: Honoraria; genzime: Honoraria; millenium: Honoraria; amgen: Honoraria. Leonard:celgene: Consultancy. Lacy:celgene: Research Funding. Witzig:celgene: Research Funding. Fonseca:medtronic: Consultancy; genzyme: Consultancy; celgene: Consultancy; amgen: Consultancy; BMS: Consultancy; otsuka: Consultancy. Greipp:celgene: Research Funding. Niesvizky:celgene: Research Funding, Speakers Bureau; Millenium: Research Funding, Speakers Bureau; Proteolix: Research Funding, data monitoring committee.

Abstract Btz (VELCADE®) is approved for patients (pts) with relapsed MM. This study characterized PK/PD of btz at 2 doses (1.0, 1.3mg/m2) after single- and multiple-dose administration, and evaluated their relationship. 24 pts with relapsed MM and creatinine clearance ≥50mL/min were randomized to btz 1.0 (n=12) or 1.3mg/m2 (n=12) on D 1, 4, 8 and 11 of a 21-D cycle (C). Pts could continue therapy for ≥8 Cs if beneficial. PK/PD samples were drawn at multiple time points on D1 and D11 of C1 and C3 over 48h. Plasma concentrations of btz were similar following administration of 1.0 and 1.3mg/m2; differences in mean plasma Cmax and AUC values were within the degree of intersubject variability (Table). There was a decrease in clearance and an increase in terminal half-life of btz on D11 vs D1 of C1.The volume of distribution of btz suggests extensive peripheral tissue distribution. After single or repeat administration, mean maximum percent inhibition of 20S proteasome activity (vs baseline) in whole blood was 70–84% and 73–83% for the 1.0 and 1.3mg/m2 doses, respectively. The percentage of pts who had >90% inhibition was greater in subsequent doses vs first dose. Reversibility of 20S proteasome inhibition in whole blood was demonstrated. PK/PD modeling revealed an exposure-response relationship, with Emax and EC50 values consistent across study days. These results confirm btz is a potent inhibitor of the 20S proteasome. The efficacy of single-agent btz has been explored and validated in the pivotal phase 2 SUMMIT and phase 3 APEX trials at 1.3mg/m2, and explored in the phase 2 CREST trial at 1.0mg/m2. Complete safety and efficacy data by dose will be presented. Mean±SD PK parameters of btz in plasma 1.0mg/m2 1.3mg/m2 1.0mg/m2 1.3mg/m2 D1/C1 (n=11) D11/C1 (n=12) an=5;bn=11;cn=10;dn=7;en=11;fn=9 Tmax (h) 0.13±0.13 0.11±0.06 0.07±0.03 0.20±0.29 Cmax (ng/mL) 56.7±36.3 112±122 106.2±46.7 88.6±47.6 AUC48h(ng·h/mL) 26.5±12.4 34.6±19.8 82.8±35.9b 82.4±28.6b AUClast (ng·h/mL) 22.6±12.6 31.5±18.6 137±106 122.2±67.4 CL (L/h) 102.1±48.1 111.6±73.6 23.2±17.8 28.0±19.8 Vβ (L) 1976±2498a 2015±2974d 1659±752c 2415±1711 t1/2λz(h) 30.7±44.8a 11.5±12.7d 78.9±50.9c 75.6±49.9 D1/C3 (n=12) D11/C3 (n=12) Tmax (h) 0.12±0.12 0.10±0.05 0.16±0.17 0.10±0.05 Cmax (ng/mL) 66.5±42.6 120.3±70.7 83.9±69.3 114.9±98.3 AUC48h(ng·h/mL) 66.4±24.1 79.4±24.5b 101.6±58.2b 85.2±18.7f AUClast (ng·h/mL) 74.8±35.8 86.0±27.6 227±181 160.7±67.1 CL (L/h) 32.2±19.0 32.1±15.4 15.1±13.9 18.2±9.2 Vβ (L) 1852±951d 2059±1231 3294±2993e 2505±1641 t1/2λz (h) 39.9±14.4d 49.1±34.6 193±169e 108.6±64.8

Abstract Abstract 1217 Poster Board I-239 Background Single autologous stem cell transplant (ASCT) is considered the standard of care after induction therapy for younger multiple myeloma (MM) patients (pts). However, it is not curative and virtually all patients will ultimately relapse. As more options are available to treat relapsed disease, the role of a second ASCT as salvage therapy is unclear. Method Retrospective review of all MM pts who received a 2nd ASCT as salvage therapy at Princess Margaret Hospital. Results Between February 1997 and July 2009, 79 MM pts received a second ASCT for relapsed MM at our institution. Median age was 60 yrs (range 39-72) at second transplant. 48 pts (61%) were male. Immunoglobulin subtype included IgG (42), IgA (21), light chain (11), nonsecretory (3), IgM(1) and IgD (1). Transplant conditioning regimen for first transplant was high dose melphalan (MEL) 140-200 mg/m2 in 67, busulphan and cyclophosphamide in 1, and combinations of MEL with etoposide (E) or TBI in the rest. 2nd ASCT conditioning consisted of MEL alone in 76, the remaining 3 had MEL with either TBI or E. The median time to relapse after the first transplant was 2.72 years (0.81-8.26), with a median interval between transplants of 3.61 years (1.63-9.59). Response to first transplant in 78 evaluable patients was 13 CR/nCR (17%), 56 PR/VGPR (72%), 9 MR/SD (12%). Nineteen pts received maintenance therapy between transplants. Two transplant-related deaths occurred following 2nd ASCT. In 73 evaluable patients, response to second transplant was 11 CR/nCR (15%), 57 PR (78%), 6 MR/SD (8%). After 2nd ASCT, with median follow up 5.92 years (71 months), median progression-free survival (PFS) was 18.5 months and median overall survival (OS) was 4.4 years. Long term progression-free status based on the progression-free interval after 1st ASCT is summarized Table 1. PFS based on progression free interval after 1st ASCT is outlined in Figure 1. Conclusions 2nd ASCT is a feasible and safe salvage therapy in relapsed MM patients. It is effective in providing a median progression free survival of 18.5 months and median overall survival of 4.4 years (52.8 months) after 2nd ASCT. This is comparable if not better than modern salvage chemotherapies. The longer the disease free interval after 1st ASCT the more effective 2nd ASCT is at extending both progression free survival and overall survival. It is reasonable, therefore, to consider a 2nd ASCT if the time to progression is greater than 2 years after first ASCT. Disclosures Chen: Celgene: Honoraria, Research Funding; Ortho Biotech: Honoraria. Trudel:Celgene: Honoraria, Speakers Bureau; Ortho Biotech: Honoraria. Kukreti:Celgene: Honoraria.

Abstract The oncogene c-maf is frequently over-expressed in multiple myeloma cell lines and patient samples and contributes to increased cellular proliferation in part by inducing cyclin D2 expression. Therefore, small molecules that inhibit c-maf and its targets could be useful chemical probes to better understand the role and regulation of this protein. We developed a high throughput chemical screen in NIH 3T3 cells stably over-expressing the promoter of the c-maf target cyclin D2 driving firefly luciferase. From a screen of 2400 off-patent drugs and chemicals, we identified 32 compounds that preferentially reduced cyclin D2 transactivation. Of these, 24 of the 32 hits belonged to the corticosteroid family of drugs. Indeed, the screen identified 24 of the 26 corticosteroids in the library. The most potent inhibitors were glucocorticoids such as dexamethasone. Mineralocorticoids such as fludrocortisone were weak hits, reflecting their weak glucocorticoid activity. The 24 glucocorticoids identified in this screen preferentially reduced cyclin D2 transactivation in the presence of c-maf. For example, the IC50 of dexamethasone was 11 ± 0.7 nM and >50 uM in NIH 3T3 cell with and without c-maf, respectively. Given the effects of glucocorticoids on c-maf in NIH 3T3 cells, we extended our investigation to multiple myeloma cell lines and demonstrated that nanomolar concentrations of the glucocorticoid dexamethasone reduced levels of c-maf protein and its target cyclin D2 within 6 hours of treatment. C-Maf was down regulated in isogenic MM1.S but not MM1.R cells respectively sensitive and resistant to dexamethasone. We also observed reductions in another c-maf target, beta integrin. Compared to cell lines RPMI 8226 and OCIMY5 that harbor the t(14;16) c-maf translocation, the concentration of dexamethasone required to reduce c-maf was approximately 50-fold lower in cell lines such as LP1 and OPM1 that lack the translocation but over-express c-maf. While dexamethasone reduced c-maf protein, no changes in levels of c-maf mRNA were detected. In both multiple myeloma and NIH3T3 cells, dexamethasone increased the ubiquitin-dependent destruction of c-maf. Finally, we linked glucocorticoids to c-maf ubiquitination by demonstrating that dexamethasone upregulated ubiquitin C mRNA at concentrations associated with the ubiquitination of c-maf. Moreover, ectopic expression of ubiquitin cDNA recapitulated the effects of dexamethasone and reduced levels of c-maf, suggesting that increased expression of ubiquitin C by dexamethasone is functionally important for dexamethasone’s effects on c-maf levels. Conclusion: a chemical biology screen identified glucocorticoids as c-maf dependent inhibitors of cyclin D2 transactivation. Glucocorticoids reduce c-maf by promoting its ubiquitination via the upregulation of ubiquitin C mRNA. This work provides new insights into the regulation of c-maf and has identified a novel mechanism by which glucocorticoids exert an anti-myeloma effect.

Abstract Background: Bortezomib (VELCADE®) is a first-in-class, reversible proteasome inhibitor with activity in multiple myeloma (MM) and other malignancies. Bortezomib showed significant activity in previous phase 2 and 3 studies in patients (pts) with previously treated MM. This international multicenter open-label phase 3b study allowed expanded access to bortezomib therapy in pts with relapsed/refractory MM treated with ≥ 2 previous lines of therapy. Methods: Pts with MM were eligible if they had received ≥ 2 prior lines of therapy and required treatment due to relapsed or progressive disease. Pts with grade ≥ 2 peripheral neuropathy (PN) were excluded. Pts received 1.3 mg/m2 IV bolus bortezomib on days 1, 4, 8, and 11 of each 3-week cycle for up to 8 cycles; dexamethasone (20 mg/d PO on the day of and day after bortezomib dose) could be added after cycle 2 for progressive disease or after cycle 4 for stable disease. Adverse events (AEs) were assessed beginning at the start of treatment and continuing until 30–42 days after treatment and were graded based on NCI-CTC version 2.0. Efficacy assessment was performed based on changes in disease burden as measured by monoclonal (M)-protein concentration in serum and urine every 2 cycles (6 weeks). Response was assessed using modified SWOG criteria: complete response (CR) was a 100% reduction in M-protein; very good partial response (VGPR), 75–99% reduction; partial response (PR), 50–74% reduction; minimal response (MR), 25–49% reduction; and stable disease, < 25% reduction. Increasing M-protein levels indicated progressive disease. Results: 624 pts in 93 centers from 21 countries received at least 1 dose of treatment and were evaluable for safety (55.3% male; median age 62.7 years). 68% of pts received 3–11 lines of previous therapy. Karnofsky performance status was ≤70 in 25.6% of pts; 141 pts (22.6%) were ≥ 70 years of age. Pts completed a median of 5 cycles of therapy (range 0–13); 39.3% of pts completed all 8 planned cycles. Grade 3/4 treatment-emergent (related and unrelated) AEs were reported in 430 pts (68.9%), with thrombocytopenia (29.2%), neutropenia (13.3%), and anemia (11.7%) the most common hematologic AEs. Grade 3/4 PN was reported in 8.2% of pts. Overall, 165 pts (26.4%) discontinued therapy due to treatment-related AEs. Best responses among evaluable pts (n = 593) included 12.0% CR, 23.1% VGPR, 19.1% PR, and 16.5% MR, for an overall response rate of 70.7%. Median time to first response was 42 days (range 7–125), and median time to best response was 63 days (range 7–235). Conclusions: Bortezomib 1.3 mg/m2 administered biweekly q3 weeks was well tolerated with manageable toxicities in pts with relapsed and/or refractory MM. Response rates with bortezomib were high, even in heavily pretreated pts, inducing > 25% CR/VGPR. This study confirms results from initial clinical trials in a broader population.