Mıkhael, Joseph

Abstract Abstract 3963 Background: Pomalidomide at doses of 2 or 4 mg/d has demonstrated excellent activity in patients with relapsed multiple myeloma (MM). Between November 2007 and November 2010, we opened 5 sequential phase 2 trials using the pomalidomide at differing doses with weekly dexamethasone (Pom/dex) regimen to study the efficacy of this regimen. Methods: The five cohorts consisted of: Cohort 1 (N=60): relapsed MM with 1–3 prior regimens, 2 mg dose; Cohort 2 (N=34): lenalidomide refractory, 2 mg dose; Cohort 3 (N=35): bortezomib/lenalidomide refractory, 2 mg dose; Cohort 4 (N=35): bortezomib/lenalidomide refractory, 4 mg dose; and Cohort 5 (N=60) lenalidomide refractory, 1–3 prior regimens, 4 mg dose. Pomalidomide was given orally 2 mg daily or 4mg daily on days 1–28 of a 28-day cycle with oral dexamethasone given 40 mg daily on days 1, 8, 15 and 22. Response was assessed by the International Myeloma Working Group Uniform Response criteria. All patients received aspirin 325 mg daily for DVT prophylaxis or full dose anticoagulation. Results: A total of 225 patients were enrolled across all 5 cohorts. One patient was ineligible and excluded from analysis. The median age was 63 years (32.0–88.0). The median time since diagnosis was 53 months. Forty percent had high-risk molecular markers. Eighty-nine percent had received previous IMIDs including thalidomide (53%) and lenalidomide (81%). Sixty-two percent had previous bortezomib and 73% had prior transplant. The median follow-up is 12.6 months, but varies from 9.4 months for the most recent cohort to 30 months for the first cohort. Sixty-nine percent are alive and 30% remain progression free. Toxicities ≥ grade 3 are shown in table 1 and patient outcomes are shown in Table 2. Conclusions: Pom/dex is remarkably active and well tolerated even in heavily pretreated patients. Responses are durable. Response rates and toxicity are similar between the 2 mg and 4 mg doses. Disclosures: Lacy: Celgene: Research Funding. Fonseca:Consulting:Genzyme, Medtronic, BMS, Amgen, Otsuka, Celgene, Intellikine, Lilly Research Support: Cylene, Onyz, Celgene: Consultancy, Research Funding.

Abstract Abstract 987 Background: IMiD® compounds are effective in immunoglobulin light-chain amyloidosis (AL), a systemic plasma cell disorder related to multiple myeloma (MM). Pomalidomide is a new IMiD® compound. Methods: Persons with symptomatic, biopsy-proved, previously-treated AL were eligible for treatment with pomalidomide if they had measurable hematologic disease, ECOG PS≥2, adequate hematologic reserve and creatinine ≤2.5 mg/dL. Pomalidomide, 2 mg/d, and dexamethasone, 40 mg/w, were given orally along with low-dose aspirin. Dose-escalation to 4 mg/d was allowed for non-responders. Exclusion-criteria were uncontrolled infection, cancer, NYHA classification >II, serum troponin-T >0.1 ng/mL, ≥grade-3 neuropathy, thrombosis or other AL therapy within 2 weeks of enrollment. 31 subjects enrolled, but only 29 are evaluble for toxicity and response due to recent enrollment. Results: Median age was 66 y (range, 52 82 y); 19 were male. Median time from diagnosis to study-entry was 36 mo (range, 0.9–104.1 mo). 24 had cardiac involvement, 10, renal involvement and 8, nerve involvement. Cardiac biomarker staging was: I, N=3, II, 21, and III, N=7. Subjects were extensively pretreated: 28 received an alkylator (including an autotransplant in 13), 15, prior lenalidomide or thalidomide and 12, prior bortezomib. 193 cycles of pomalidomide were given to 29 subjects. 11 subjects had protocol-specified dose-increases (no response) and 16, dose-reductions (AEs). 20 subjects had dexamethasone dose-reductions. ≥Grade-3 AE's ≥possibly attributed to therapy occurred in 21 subjects. 7 of these subjects had only hematologic AE's. Neutropenia was the most common severe AE (N=10); severe thrombocytopenia occurred in 2 subjects. Other grade-3/-4 AEs included infection/fever (N=3); fatigue (N=4), and pleural effusion, ascites/edema, and edema each in one patient. 1 subject each had dyspnea, increased creatinine, thrombosis, muscle weakness, atrial tachycardia, and diarrhea. There were 2 episodes of syncope attributed to AL rather than therapy. A subject died 5 d after beginning therapy presumably from cardiac AL. As of 7/27/010, median time on-study is 8.4 mo (range, 0.2–16.2 mo). 18 subjects discontinued therapy for: progression/death (N=9); consent withdrawal (N=4), AE (N=3) and physician choice (N=2). Overall hematologic response rate (N=29) is 38% (95% CI, 20–58%) There were 8 PRs and 3 VGPRs including 4 PRs and 2 VGPRs among 14 subjects failing prior lenalidomide and/or thalidomide. 3 subjects had confirmed organ responses (2 heart and 1 kidney) and 4 unconfirmed organ responses. 1 y survival and PFS are 77% (95% CI, 60–98) and 56% (95% CI, 36–85). Conclusion: These data suggest that pomalidomide could provide a safe and effective therapy in previously-treated persons with AL including those failing lenalidomide and/or thalidomide. Disclosures: Dispenzieri: Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Off Label Use: Non-FDA approved indication. Gertz:Celgene: Honoraria. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Fonseca:Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy, Research Funding; Genzyme: Consultancy; Onyx: Research Funding; Otsuka: Consultancy; Medtronic: Consultancy. Bergsagel:Celgene: Consultancy; Centocor: Consultancy; Genentech: Consultancy; Amgen: Consultancy; Novartis: Consultancy. Stewart:Millennium: Consultancy; Celgene: Honoraria. Lacy:Celgene: Research Funding.

Abstract Abstract 1749 BACKGROUND: We have previously reported that transformation of a myeloproliferative neoplasm (MPN) to acute leukemia or blast phase (MPN-BP) is accompanied by a median survival of 2.6 months (range 0–24.2 months) (Mesa et. al. Blood 2005) despite treatment. Allogeneic stem cell transplantation (ASCT) offers a potential for cure. We reviewed 13 patients with MPN – BP who were candidates for ASCT, and 8 of those patients received ASCT after induction chemotherapy. METHODS: Retrospective analysis of individuals who had a clear antecedent myeloproliferative neoplasm (essential thrombocythemia (ET), polycythemia vera (PV), or myelofibrosis (MF) (either primary (PMF) or post ET/PV)), transformed to MPN-BP, and were candidates for ASCT. Clinical characteristics at each phase of illness, therapy at each phase of illness, and outcome of ASCT were assessed. RESULTS: Patients (MPN details): Thirteen patients (8 male, 5 female, median age at diagnosis of MPN 42 years in those who underwent ASCT and 64 years in those who did not receive ASCT (combined median 53 years, range 26–70)) were identified who met the inclusion criteria, of whom 2 had ET, 4 PV, 2 Post-ET MF, 1 Post-PV MF and 4 PMF. Jak2-V617F mutation was present in 7 of 8 patients tested. Treatments used during the MPN phase included hydroxyurea in 9 (+ busulfan in 1 and + anagrelide in 1), and thalidomide/prednisone in 2 (two patients received no treatment prior to MPN-BP). Patients (MPN-BP details): Transformation of an MPN to blast phase (from diagnosis of MPN) occurred after a median of 11 years in those who underwent ASCT and 8 years in non-ASCT (range 3 months to 30 years). At the time of MPN-BP diagnosis, 9 patients had an abnormal karyotype, 3 with complex karyotypes, 3 with trisomy 8 (sole abnormality), 1 with del(7q), 1 with del(13q). Leukemic induction consisted of standard anthracycline/cytarabine combination therapy (+/− etoposide), except for one patient received a study medication voreloxin. One patient who did not receive ASCT had remission after induction, but later expired from relapse, two expired soon after leukemic transformation, and two were too ill to receive induction. In the ASCT group (N=8), 5 patients achieved complete remission (CR) of their leukemia/return to MPN chronic phase (one of the five patients required a second induction to achieve CR), while 3 patients were considered primary induction failures due to persistence of > 5% blasts in the blood (2) or marrow (1) at the time of pre-transplant response assessment. The median time from diagnosis of MPN-BP to ASCT was 128 days. ASCT Details and Outcomes: Patients (median age of 55 years at time of ASCT; range 44–73) underwent ASCT (all HLA identical, 3 matched unrelated donors, 5 matched sibling donors) with either reduced intensity conditioning (n=6) or fully myeloablative conditioning (n=2). After a median follow-up of 488 days (range 127 – 1206), 6 of 8 patients are alive and free of disease. MPN-BP recurred in two patients at day 69 and 77 post-transplant; both patients eventually died of progressive leukemia, one after a second transplant. Acute GVHD occurred in 3 patients (1 grade III, 2 grade II), and chronic GVHD in 4 (2 mild, 2 moderate). All five patients who achieved CR (marrow and PB blasts < 5%) after induction therapy remain in continuous CR, while 2 of the 3 patients with evidence of persistent leukemia relapsed and died of MPN-BP. No patient died of transplant-related causes and all patients engrafted promptly. CONCLUSION: Rapid induction followed by ASCT can offer a curative path for individuals with MPN-BP. Although limited by small numbers, our data suggest that leukemic clearance (marrow blast percentage < 5%) prior to ASCT is associated with improved outcome. Disclosures: Mesa: Incyte: Research Funding; Lilly: Research Funding; SBio: Research Funding; Astra Zeneca: Research Funding; NS Pharma: Research Funding; Celgene: Research Funding.

Abstract Abstract 1977 Introduction: Transplant options are limited for adult patients (pts) who lack a fully matched related or unrelated donor. We hypothesized that in-vivo T-cell depletion with r-ATG would allow safe allo-SCT from mismatched, unrelated donors, thus expanding the potential donor pool for pts with hematologic malignancies who require allo-SCT. Patients and Methods: Thirty seven adult pts (age 20 – 70, median 45) underwent a first unrelated, mismatched, allo-SCT between 1/1/2006 and 6/30/2011 at Mayo Clinic Arizona for hematologic malignancy (35 PBSC, 2 marrow). All pts had at least a one allele or one antigen mismatch (MM) at HLA-A, -B, -C, or -DRB1, and all except one pt received r-ATG as part of the GVHD prophylaxis strategy (dose range 2.5 – 10 mg/kg in daily dose of 2.5 mg/kg depending on degree of mismatch, with the last dose generally given on day −1). One pt received Campath after experiencing anaphylaxis to r-ATG. Pts were transplanted for acute myeloid leukemia (n = 19; 10 CR1, 6 CR2, 3 other), acute lymphoblastic leukemia (n = 8; 4 CR1, 4 CR>/= 2), chronic myeloid leukemia (n = 1), myelodysplastic syndrome (n = 5), or non-Hodgkin lymphoma (n = 4). Conditioning was myeloablative in 20, reduced intensity in 16, and non-myeloablative in 1. Mismatches were as follows: 1-allele MM (n = 7); 1 antigen MM (n = 15); 2 allele MM (n = 4); 1 antigen, 1 allele MM (n = 7); and 2 antigen MM (n = 4). Additional GVHD prophylaxis included tacrolimus plus either methotrexate (n =21), mycophenolate mofetil (n = 14), or other (n = 2). Results: The median follow-up for surviving pts is 12 months. As of 6/30/11, 31 pts were alive, and 6 had died of the following causes: multiorgan failure (n = 1), relapse (n = 3), and veno-occlusive disease (n = 2). To date, there have been no deaths related to acute or chronic GVHD. The 1- and 2-year estimated rates of overall survival are 84.5%/78.8% (Fig. 1); of progression-free survival 79.7%/72.0%. The estimated rate of relapse at 1 and 2 years is 11.8%/18.7%, and of non-relapse mortality 8.1%/10.5%. Four pts (10.8%) have developed severe (grades III-IV) acute GVHD by day 100 (days 19, 27, 30, 43; one pt after withdrawal of prograf due to transplant-associated microangiopathy). No late onset severe acute GVHD has been seen. Moderate to severe NIH-defined chronic GVHD occurred in a single pt at risk (cumulative incidence estimate 2.4% at 1 year, 4.7% at 2 years; Fig. 2). Four pts have reactivated EBV, with one developing PTLD (all have been treated with Rituximab). CMV reactivation was seen in 24 pts (65%), CMV disease in 4, with no deaths directly related to CMV. Conclusions: In vivo T-cell depletion with r-ATG abrogates severe acute and chronic GVHD, and allows use of mismatched unrelated donors for allo-SCT in adult pts with otherwise incurable hematologic malignancies. Long-term survivors are generally free of severe chronic GVHD, with good quality of life. There does not appear to be an increased incidence of disease relapse, and non-relapse mortality is low. This approach is safe, effective, and considerably expands the donor pool for adult pts who require allo-SCT. Disclosures: Reeder: Celgene: Research Funding; Millennium Pharmaceuticals Inc.: Research Funding; Novartis: Research Funding. Mesa:Incyte: Research Funding; Lilly: Research Funding; SBio: Research Funding; Astra Zeneca: Research Funding; NS Pharma: Research Funding; Celgene: Research Funding.

Abstract Background: Ixazomib is an experimental, orally bioavailable, proteasome inhibitor that has demonstrated anti-tumor activity in relapsed multiple myeloma (MM). In the dose escalation studies, ixazomib was tolerated up to a dose of 5.5 mg given every week as a single agent, while a dose of 4 mg was utilized in the combination studies with lenalidomide. We undertook this study to examine the efficacy and tolerability of the two doses of ixazomib in combination with dexamethasone in patients with relapsed MM. Patients and methods: This was a randomized phase 2 study of two doses of ixazomib (4mg; Arm A or 5.5 mg; Arm B) given weekly for three weeks with a week off along with weekly dexamethasone (40 mg) in patients with relapsed MM, who are proteasome inhibitor na•ve (including bortezomib) or have received less than 6 cycles of therapy with bortezomib and had a PR or better with no progression at the time of discontinuation. The primary objective was to determine the confirmed overall response rate (>=PR); secondary objectives included progression free and overall survival. A total of 71 patients were accrued from February 2013 to April 2015; one patient was ineligible. Results: Baseline characteristics were similar in the two arms; median age across the study was 70 years (46-84); 53% were male. Median number of prior therapies was 4 (range 2-6); 90% of the patients had prior IMiDs, 70% had prior transplant and 29% had prior bortezomib. At a median follow up of 10 months, 17 (49%) and 19 (54%) of patients had disease progression in arms A and B respectively with 12 (34%) patients in each arm still continuing on treatment. All patients in each arm were evaluable for response; the overall response rates were 31% in arm A (95%CI: 17-49) and 51% (95%CI: 34-69) in Arm B. The depth of response, event free survival and overall survival are outlined in Table 1. Among the patients with no prior bortezomib exposure the response rates were 38% for Arm A and 52% for Arm B. The treatment was well tolerated with 2 patients in each arm discontinuing treatment for adverse events; there were no on study deaths. A grade 3 or higher AE that was at least possibly related to treatment was seen in 21% and 54% in Arms A and B respectively; with 15% and 37% hematologic and 6% and 29% non-hematologic AEs. The most common attributable toxicities encountered included fatigue, thrombocytopenia, diarrhea and nausea with more grade 3 toxicities among Arm B. Peripheral neuropathy, possibly related to ixazomib, was seen in 55% (only grade 1 or 2) in arm A and 43% (2 patients with grade 3) in Arm B. Toxicities led to dose reduction of ixazomib in 17% and 43% of patients in Arm A and B respectively; the median number of cycles administered were 5 (1-24) and 5 (1-22) respectively. Conclusions: Ixazomib in combination with dexamethasone was well tolerated with significant anti-myeloma activity in this group of patients with relapsed MM. Deep responses including stringent CR were observed. The higher dose of ixazomib appears to be associated with a higher response rate but with higher rate of adverse events requiring dose reductions. Table 1. Treatment outcome in all patients Arm B (4 mg) (N=35) Arm C (5.5 mg) (N=35) Response Rate 31% (95%CI: 17-49) 51% (95%CI: 34-69) No. of Responders 11 18 sCR 0 1 CR 1 0 VGPR 7 8 PR 3 9 MR 5 1 Median Overall Survival1 NA NA 6 Months 100% 100% Median Event Free Survival1,2 8.4 mos (95%CI: 4.3-13.2) 8.2 mos (95%CI: 3.8-16.3) %Event Free at 6 Months 60% (95%CI: 45-81) 60% (95%CI: 45-81) Median Duration of Response1 16.7 mos (95%CI: 9.3-22.0) 16.3 mos (95%CI: 7.0-20.1) Median Time to Response 1.1 mos (range: 0.8-3.6) 1.0 mos (range: 0.8-7.5) CI: confidence interval; mo: month; NA: not attained 1Kaplan Meier 2Event-free survival time is defined as the time from registration to the first of disease progression, death due to any cause, or subsequent treatment for multiple myeloma. Disclosures Kumar: Celgene: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; Skyline: Consultancy, Honoraria; Onyx: Consultancy, Research Funding; Novartis: Research Funding; Janssen: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; BMS: Consultancy.

Abstract Background: Dexamethasone (dex) is an integral part of various anti-myeloma regimens both in the frontline and relapsed/refractory (RR) setting. Several clinical trials have shown that dex adds to the efficacy of novel therapeutic agents for multiple myeloma (MM). Yet, a substantial number of patients are intolerant to even the standard of care low-dose dex (40 mg weekly), especially in heavily pre-treated RRMM, possibly due to cumulative steroid toxicities and thus, require dex dose adjustments. There is a concern of compromising the efficacy of anti-MM regimens by adjusting the dex dose lower. We describe the frequency of dex dose adjustment, characteristics of patients who required it and its effect on patient outcomes in a large prospective clinical trial of pomalidomide (pom) and dex in RRMM (MC0789). Methods: We utilized data from the Pom-dex trial (MC0789), which treated RRMM patients in different cohorts of pom (2 vs. 4 mg; 21 vs 28 days cycle) with fixed dose dex (40 mg orally weekly). Patients were divided into 2 subgroups, with any dose adjustment/elimination of dex vs. not. Continuous and categorical variables were compared between the two groups using two-sample t-test/Wilcoxon rank sum test or Chi-squared test, respectively. Logistic regression and Cox regression models were used to find the univariate and stepwise multivariate predictors of response to treatment and overall mortality, respectively. Kaplan-Meier method was used to estimate overall survival (OS) at 1, 3, and 5 years. All statistical tests were two-sided with the alpha level set at 0.05 for statistical significance. Results: Results from the MC0789 clinical trial have been reported previously. Almost half of all treated patients in this trial had dex dose adjusted (n=175/343; 51%). The median number of cycles for the first dose adjustment in this group was 3 (range 1-62), with 46.5% of patients (n=82) having multiple dose adjustments and majority (58.3%, n=102) within the first 3 cycles of treatment. Patients in the dose adjustment group were significantly older (mean 65 vs 60 years; p=0.0001). Males, Whites and patients diagnosed before 2006 or with normal cytogenetics also had a higher incidence of dex dose adjustment, though this was not statistically significant. Patients with dex dose adjustment had a longer duration of treatment (mean 339 days) as compared to the non-adjusted cohort (mean 123.65 days) (95% CI 160.13, 270.58; p <0.0001). Dex dose adjustment was associated with a higher probability of responding in the clinical trial after a univariate (p<0.001) as well as multivariate (p<0.001) analysis. Patients with dex dose adjustment also had a significantly better OS at 1, 3 and 5 years by univariate (p<0.001) and multivariate (p<0.001) analysis. (Figure 1) The only other significant factor was lesser number of prior regimens (3 or less), associated with a higher probability of response (p=0.002) and survival (p<0.001). Conclusion: Our analysis established that in these heavily pre-treated RRMM patients, appropriate dose adjustment of dex did not compromise their response rates; patients remained on treatment significantly longer and had an improved survival. Majority of patients (58.3%) requiring dex dose adjustment had it instituted early during treatment (<3 cycles), suggesting that early disease progression was less likely to determine dex dose continuation or adjustment. Appropriate dex adjustments should be judiciously employed as they may ensure longer treatment duration with novel anti-MM therapeutic agents, conferring superior response and survival in this difficult to treat MM subgroup. This also paves the path to further optimize dex dose in various anti-MM regimens, especially in these patients who are more likely to be intolerant to it. Disclosures Kumar: Skyline, Noxxon: Honoraria; Celgene, Millennium, Onyx, Janssen, Noxxon, Sanofi, BMS, Skyline: Consultancy; Celgene, Millennium, Onyx, Novartis, Janssen, Sanofi: Research Funding.

Abstract Abstract 1965 Background: Pomalidomide is an immunomodulatory compound to be used for heavily pre-treated patients with relapse and refractory multiple myeloma and has shown considerable efficacy in recent clinical trials. It is not clear how patients may respond to other therapies, once the disease becomes refractory to pomalidomide. We examined this question among a cohort of patients receiving pomalidomide therapy in phase 2 clinical trials. Methods: Patients enrolled in an ongoing phase 2 clinical trial of pomalidomide (2-4 mg daily) along with dexamethasone (40 mg weekly), in relapsed myeloma, form the study population. Several cohorts of patients (>= 3 prior therapies not specified, lenalidomide refractory, and lenalidomide and bortezomib refractory patients were enrolled sequentially in this trial (Lacy, M.Q., et al., J Clin Oncol, 2009. 27(30): p.5008–14). Only those patients who have gone off study for disease progression were included in the current analysis. Details of subsequent therapies and survival data were obtained from the medical records. Results: Forty-seven patients from among 142 patients enrolled on the clinical trial between November, 2007 and April, 2010 were included in the study. The median (range) duration of pomalidomide therapy was 4 (0.6-16) months. 15 (32%) patients were lenalidomide refractory and 11 (23%) were refractory to both lenalidomide and bortezomib at the time of study entry. The best confirmed response to pomalidomide was MR (Minimal Response) or better in 23 patients (52%). Various regimens were employed following relapse on pomalidomide. The response to the first regimen following relapse in the 34 patients where salvage therapy was initiated is as shown in Table 1. Overall, 81 regimens were employed across 34 patients; median (range) number of regimens per patients was 1 (0-8). The response rates to the different regimens were as shown in the Table 1. The median overall survival (OS) from the time of progression on pomalidomide was 14.7 months (95% CI; 4, NR). The OS was similar between those patients who had a response to pomalidomide (MR or better) and those who did not. However the OS was shorter for patients who were refractory to lenalidomide and bortezomib (2.1 months) compared to those who were lenalidomide refractory only (6.5 months), and the non-refractory group (NR), P=0.06. Conclusions: This study confirms poor outcome of the patients relapsing after all available therapies. It also gives interesting insights into the activity of different regimens among patients who have relapsed after pomalidomide. The findings once again highlight the incurable nature of the disease and warrant further investigation to develop newer effective treatment regimens for this group of patients who presently do not have effective therapeutic options especially in the relapsed setting. Regimens: ASCT: Autologous Stem Cell Transplantation, Bz: Bortezomib, Mel=Melphalan, Dex: Dexamethasone, CRD: Cyclophosphamide, Revlimid (Lenalidomide), Dexamethasone, CTX; Cyclophosphamide, Len; Lenalidomide, Sor: Sorafenib, VDT-PACE: Velcade (Bortezomib), Dexamethasone, Thalidomide, Cisplatin, Adriamycin, Cyclophosphamide, Etoposide. Response: SD; Stable Disease; Prog; Progression MR: Minimal Response; PR: Partial Response. Disclosures: Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Mikhael:Celgene: Research Funding; Onyx: Research Funding; Novartis: Research Funding. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria.

Abstract Background: The anti-apoptotic protein BCL-2 has been implicated in mediating the survival of multiple myeloma (MM) cells. Venetoclax is a potent, selective, orally bioavailable small-molecule BCL-2 inhibitor. Venetoclax induces cell death in MM cell lines in vitro and primary MM samples ex vivo. Certain genetic subtypes of MM cells are particularly sensitive to venetoclax, including t(11;14) cells, which express a high ratio of BCL2 to MCL1 (venetoclax resistance factor). The current Phase 1 study evaluates safety, efficacy, and pharmacokinetics (PK) in patients (pts) with relapsed/refractory MM. Methods: Primary objectives are to evaluate safety, PK, and recommended phase two dose; other objectives include assessing preliminary efficacy and the impact of chromosomal abnormalities. In dose-escalation (DE) cohorts, venetoclax was given orally daily at 300, 600, 900, or 1200 mg after a 2-week dose ramp-up (3+3 design). Patients in the safety expansion (SE) cohort received 1200 mg daily after ramp-up. All patients were monitored for tumor lysis syndrome (TLS). Results: As of June 17, 2015, 37 patients were enrolled in the study: 30 from DE cohorts and 7 from the SE. Median (range) age was 66 years; 19 (51%) were female. Fourteen were ISS stage I, 13 stage II, 8 stage III, 2 unknown. The median (range) number of prior lines of therapy was 6 (1-19). Thirty-two had prior bortezomib (20 refractory), 35 lenalidomide (18 refractory), and 26 had prior stem cell transplant. Fourteen patients had t(11;14), 4 had t(4;14), 5 had del 17p, and 17 had del 13q. Adverse events (AEs) in ≥20% of patients were nausea (49%), diarrhea (38%), vomiting (30%), anemia (27%), fatigue (24%). Grade 3/4 AEs (≥10%): thrombocytopenia (22%), anemia (19%), neutropenia (11 %). Serious AEs (≥2 patients): pyrexia (n=3), cough, malignant neoplasm progression, and sepsis (2 each); 2 (upper abdominal pain and anemia) were possibly related to venetoclax. Thirty (81%) patients have discontinued venetoclax: 24 due to PD, 3 for AEs (worsening shortness of breath, hypokalemia, and nausea), 2 withdrew consent, 1 due to death (brain hemorrhage following injury). Four deaths occurred (2 due to PD, 1 due to brain hemorrhage, 1 due to pneumopathy). Two of the 6 patients in the 600 mg cohort experienced DLTs of upper abdominal pain and nausea with abdominal pain. No patients met the criteria for laboratory or clinical TLS. Based on preliminary PK (n=21), the mean Cmax and AUC24 were ~dose-proportional at all studied doses (300, 600, 1200 mg) except 900 mg, and dose-normalized venetoclax exposure in MM was similar to that in CLL and NHL pts. Thirty-two of the 37 patients were evaluable for preliminary efficacy (Table). Two patients, both t(11;14), achieved a complete response (1 at 600 mg and 1 at 900 mg). Responses were first achieved at 1.8 and 1.1 months and were maintained for 9.7 and 9.0 months, respectively (900 mg pt remains in CR). Among the 16 patients receiving 1200 mg in the DE or SE cohort, 6 of whom had t(11;14), 5 achieved SD, 6 experienced PD, and 5 are not yet evaluable. Conclusions: Venetoclax monotherapy had a tolerable safety profile in heavily-pretreated relapsed/refractory MM, and no new safety signals were observed compared to other venetoclax studies. The study continues to enroll in the SE cohort at 1200 mg. Responses (including CR) and longer time on venetoclax were observed in t(11;14) patients. These early results suggest that venetoclax has single agent activity, most prominently in t(11;14) patients. Figure 1. Figure 1. Disclosures Kumar: Celgene: Research Funding; Millenium/Takeda: Research Funding; Onyx: Research Funding; AbbVie: Research Funding; Janssen: Research Funding; Sanofi: Research Funding; Celgene, Millenium, Sanofi, Skyline, BMS, Onyx, Noxxon,: Other: Consultant, no compensation,; Skyline, Noxxon: Honoraria. Off Label Use: Venetoclax is an investigational drug that is not yet approved in this indication.. Vij:Takeda, Onyx: Research Funding; Celgene, Onyx, Takeda, Novartis, BMS, Sanofi, Janssen, Merck: Consultancy. Kaufman:Janssen: Consultancy; Spectrum: Consultancy; Merck: Research Funding; Celgene: Consultancy; Onyx: Consultancy; Novartis: Consultancy; Novartis: Research Funding; Onyx: Research Funding. Mikhael:Sanofi: Research Funding; AbbVie: Research Funding; Celgene: Research Funding; Onyx: Research Funding. Moreau:Takeda: Other: Adboard; Janssen: Other: Adboard; Celgene: Other: Adboard; Novartis: Other: Adboard; Amgen: Other: Adboard. Alzate:AbbVie: Employment, Equity Ownership. Morris:AbbVie: Employment, Equity Ownership. Ross:AbbVie: Employment, Equity Ownership. Dunbar:AbbVie: Employment, Equity Ownership. Zhu:AbbVie: Employment, Equity Ownership. Maciag:AbbVie: Employment, Equity Ownership. Agarwal:AbbVie: Employment, Equity Ownership. Leverson:AbbVie: Employment, Equity Ownership. Enschede:AbbVie: Employment, Equity Ownership. Humerickhouse:AbbVie: Employment, Equity Ownership. Touzeau:AbbVie: Research Funding.

Abstract Abstract 3055 Lenalidomide (Revlimid®) and dexamethasone is an effective regimen for relapsed/refractory (rel/ref) multiple myeloma (MM) patients (pts) with an overall response rate of 60% and median time to progression of 13.4 months (Dimopoulos ME, et al. Leukemia 2009; 23: 2147-52). We combined lenalidomide with the alkylating agent combination of cyclophosphamide and prednisone—an older regimen with minimal cumulative myelosuppression and good activity as second or third line therapy (Trieu Y, et al, Mayo Clin Proc 2005; 80: 1582). The CPR regimen consisted of cyclophosphamide (CY) on days 1, 8, and 15, lenalidomide on days 1–21 and prednisone 100 mg q 2 days in a 28-day cycle. ASA 81 mg/day was given as DVT prophylaxis. Three dose levels were evaluated using a 3 × 3 dose escalation design. Thirty-two pts were entered between 11/2007-06/2009; median age was 64 (42-80) yrs, 60% were male, and immunoglobulin isotype was IgG in 19 (62%), IgA in 8 (25%) and light chain in 4 (13%) pts. Median β2-microglobulin level was 257 (92-767) nm/L, albumin 39 (34-48) g/L, creatinine 83 (50-126) μmol/L, platelet count 355 (75-479) × 109/L and ANC 2.5 (1.1-6.1) × 109/L. The median number of prior regimens was 2 (1-5). Prior therapy included: ASCT (single in 91%; double in 19%), thalidomide (28%) and bortezomib (50%). FISH cytogenetics were available in 13 pts; 1 had del 13q but none had t(4;14) or del p53. Table 1 summarizes protocol treatment delivered. Table 1. Dose level N Cyclophosphamide dose (mg/m2) Lenalidomide dose (mg) Prednisone dose (mg) Median # cycles given 1 3 150 15 100 12 (12–34+) 2 3 150 25 100 10 (9–23) 3 26 300 25 100 17 (5–28+) 1–3 (All) 32 150–300 15–25 100 19 (5–34+) Dose limiting toxicity was not observed during cycle 1 at any dose level. Grade 3–4 toxicities during the trial included: thrombocytopenia in 7 (22%) and neutropenia in 9 (29%), managed with dose reduction and/or growth factors; five episodes of febrile neutropenia occurred, all at dose level 3. In cohort 3, other grade 3–4 non-hematologic toxicities included 1 episode each of abdominal pain/bacteremia, hypokalemia, fatigue, sick sinus syndrome, cardiac amyloidosis, perforated diverticulum and 2 episodes of DVT. Two heavily pretreated pts developed 2° MDS, including 1 previously treated for lymphoma, 43 and 190 mos after the diagnosis of MM. The best response using modified EBMT criteria was documented at a median of 7 (1-26) cycles and included the following: dose level 1 (1 CR, 2 PR); dose level 2 (1 VGPR, 2 PR); dose level 3 (4 CR, 14 VGPR, 11 PR, 1 MR and 1 stable disease). At a median F/U of 16 (5-34) months, 13 pts remain on study and 18 have progressed at a median of 10 (2-23) mos; 1 was lost to F/U and 9 have died of progressive MM. The 1-year actuarial OS and PFS rates are 93% (95% CI 76–98%) and 78% (95% CI 60–89%), respectively. We conclude: 1) the combination of full doses of the agents in CPR can be given in a 28 day cycle with an acceptable safety profile; 2) the objective response rate (CR + PR + MR) in all 32 pts to date is 94%; 3) the 1-year OS of 93% and PFS of 78% compare favorably with other 3-drug combinations in rel/ref MM pts; 4) further evaluation of this regimen in newly diagnosed pts would be of interest. Disclosures: Reece: Celgene: Honoraria, Research Funding. Off Label Use: Combination of lenalidomide and cyclophosphamide and prednisone in relapsed and refractory myeloma patients. Chen:Celgene Corporation: Consultancy, Honoraria, Research Funding. Kukreti:Celgene: Honoraria.

Abstract Abstract 3063 Background: The combination of Cyclophosphamide, Bortezomib, and Dexamethasone (CYBOR-D) is proven to be highly active and effective in multiple myeloma. (Reeder, Leukemia 2009) We aim to evaluate the safety and efficacy of this regimen in a separate plasma cell neoplasm, AL Amyloidosis. The primary endpoint of this study is hematologic response. Complete hematologic response is defined as normalization of the free light chain ratio with no evidence of a monoclonal protein by immunofixation. Partial hematologic response is defined as a 50% reduction in M-spike or absolute light chain level (Gertz Am J Heme 2006). Methods: We report a series of patients with symptomatic AL Amyloidosis who received treatment with a combination of Bortezomib (1.3mg/m2 on days 1, 4, 8, and 11 every 28 days or 1.5 mg/m2 weekly), Cyclophosphamide (300 mg/m2 orally weekly) and Dexamethasone (40 mg weekly). We include patients in this study regardless of autologous bone marrow transplant candidacy or previous treatment history. Results: Fifteen patients with AL amyloidosis received two to six cycles of CYBOR-D. The treatment history, bone marrow transplant candidacy prior to treatment, hematological response, and status of transplant after therapy are shown in table 1. Of note, 8 (53%) had symptomatic cardiac involvement all of whom had elevated levels of both cardiac biomarkers (Troponin T and B-natriuretic peptide). Complete hematological response occurred in 11 patients (73.3%) with partial hematological response in 3 patients (20.0%). One patient (6.6%) did not achieve a partial response but did receive autologous bone marrow transplant after treatment with CYBOR-D. Median time to response was 2 months. Six patients (40%) had objective evidence of kidney response to therapy with a greater than 50% decrease in proteinuria. Conclusions: CYBOR-D produces a rapid and complete hematological response in the majority of patients with AL amyloidosis regardless of previous treatment history or bone marrow transplant candidacy. Overall, it is well tolerated with few side effects that included peripheral neuropathy and infectious complications. Two patients originally determined to be not eligible for transplant improved sufficiently on CYBOR-D to become eligible and then went on to receive autologous bone marrow transplant. The retrospective nature and small sample size limit this study, and prospective, randomized studies are needed to further elucidate the role of this regimen in AL amyloidosis. Disclosures: Stewart: Millennium Pharmaceuticals, Inc.: Honoraria, Research Funding; Celgene: Honoraria. Fonseca:Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Celgene: Consultancy, Research Funding; Genzyme: Consultancy; Onyx: Research Funding; Otsuka: Consultancy; Medtronic: Consultancy.