ALBERT

Description: Abstract 990 Introduction: This study aimed to determine activity and safety of weekly bortezomib (Takeda Inc) and temsirolimus (Pfizer Inc) in patients with relapsed/refractory Multiple Myeloma (MM). Methods: Eligibility criteria included: 1) patients with relapsed or relapsed/refractory MM with any prior lines of therapy including bortezomib, 2) no chemotherapy within 3 weeks, or biological/novel therapy within 2 weeks. Primary endpoint was the percent of patients with at least a minimal response (MR). Results: Twenty patients were enrolled on the phase I study and 43 on the phase II study. The MTD was determined at 1.6 mg/m2 bortezomib Days 1, 8, 15, and 22 every 35 days in combination with 25 mg IV temsirolimus Days 1, 8, 15, 22, and 29 every 35 days. Twenty % were stage III by ISS staging system in the phase I, and 21% in the phase II. The overall response rate of MR or better in the Phase II study was 20/43 (47%, 95%CI: 33,60), with 5% CR, 9% VGPR, 19% PR and 14% MR. Progression without any response occurred in just 1 patient (3%). One patient had an unconfirmed PR, but was included in the stable disease category. An additional 3 (6%) patients were unevaluable in the phase II trial because they did not complete their first cycle of therapy and had no follow up laboratory results for response. If these patients are excluded, the ORR including MR improves to 50% (95% CI: 36,64). The overall response rate in the phase I study was 20% with responses occurring in all the stages of the dose escalation. If three patients who were unevaluable in the phase I trial are excluded, then the response rate of evaluable phase I patients is 24% (95% CI: 9,46). Response was also evaluated by whether patients were bortezomib-refractory or not. These were defined as progressing while on therapy or progressing within 60 days of completing bortezomib therapy. Fifty-one patients had received bortezomib as part of prior treatment. Of these patients, 32 were refractory to bortezomib therapy immediately prior to study entry, and an additional 2 pts were refractory at prior time points. Responses observed among the 32 patients refractory to their most recent bortezomib therapy include 3 PR and 3 MR (ORR: 19%, 95% CI: 9,34). Another 21 patients had SD, 2 PD and 3 patients were unevaluable. Of the evaluable patients, the ORR was 6/29 (21%). Responses observed among the 19 patients who were not refractory to their last bortezomib treatment include 2 VGPR, 5 PR and 3 MR with 6 patients with SD, 0 PD and 3 unevaluable. The ORR among the evaluable patients who received bortezomib but were not refractory was 62%. Median time to response of MR or better (min, max) among all patients was 1.7 months (0.5,14.2) and among phase II patients 1.3 months (0.5,8.0). Median duration of MR or better (min, max) among all patients is 5.2 months (0.5,15.8) and among phase II patients is 4.6 months (0.5,10.8). Median duration of PR or better response (min, max) among all patients is 6.0 months (1.8,15.8) and among phase II patients is 5.2 months (1.8,10.8). The median time to progression for all patients in the phase I and II studies was 7.3 months (95% CI: 5.7 –17.2) and the median progression free survival was 6.4 months (95% CI: 4.8–7.4). The median overall survival in all phase I and II patients was 11.4 months (95%CI: 8.6-undetermined). Three deaths occurred during therapy in the phase I and II studies, 1 of septic shock, 1 with H1N1 infection, and 1 with cardiac amyloid and ventricular arrhythmia. The most common G1-4 toxicities that occurred in 〉 25% of patients included cytopenias, hypertrigyceridemia and diarrhea. Grade 3 and 4 thrombocytopenia occurred in 48% of patients in the phase I and II studies, G3 and 4 neutropenia occurred in 36%, and anemia in 26% of phase I and II patients. G3 and 4 hypertriglyceridemia occurred in 5% and diarrhea in 9%. Peripheral neuropathy (PN) was rare with no G3 or 4 neuropathy reported. Overall, there was 34% grade 1 and 2 PN seen. Conclusions: The combination of weekly bortezomib and temsirolimus showed an encouraging response rate in heavily pretreated patients with relapsed or refractory MM, with an overall response rate in evaluable patients as part of the phase II portion of the trial of 50%, and a 21% ORR including MR or better in evaluable bortezomib refractory patients. Cytopenias were the most common toxicities, specifically thrombocytopenia, as well as GI toxicity, with side effects proving manageable. Significant PN was rare in this study. Disclosures: Ghobrial: Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Vij:Novartis: Honoraria; Eisai: Speakers Bureau. Munshi:Millennium Pharmaceuticals: Honoraria, Speakers Bureau. 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. Anderson:Millennium Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Richardson:Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees.

Description: PURPOSE: This study aimed to determine activity and safety of the CXCR4 inhibitor plerixafor in combination with bortezomib and dexamethasone in patients with relapsed or refractory Multiple Myeloma (MM). This was based on our preclinical studies showing that plerixafor (Mozobil, Sanofi Corporation) induces de-adhesion of MM cells and sensitization to bortezomib in preclinical animal models. PATIENTS AND METHODS: Theprimary endpoint of the phase I study was the maximum tolerated dose (MTD) and for the phase II study, the safety and response rate of the combination. Eligibility criteria included patients with relapsed or relapsed/refractory MM with 1-5 prior lines of therapy including bortezomib (unless patients were refractory to bortezomib). The phase I included 8 cohorts with different doses and two treatment schedules. In cohorts 1-5, patients received plerixafor at the recommended dose sq on days 1-6 of each cycle and bortezomib at the recommended dose twice a week on days 3, 6, 10, and 13 every 21 days. In cohort 5b-6, plerixafor was given at the recommended dose sq on days 1, 3, 6, 10, and 13 and bortezomib was given at the recommended dose twice a week on days 3, 6, 10, and 13 every 21 days. For the phase II portion patients received plerixafor at the MTD established in phase I of trial, 320 mcg/kg sq on days 1, 2, 3, 6, 10, and 13. Bortezomib was given 1.3 mg/m2 IV or sq twice a week on days 3, 6, 10, 13, every 21 days. Dexamethasone was given at 40mg on days of Bortezomib. RESULTS: A total of 58 patients were enrolled on this study from June 2009 to March 2015, with 25 on the phase I and 33 on the phase II study. In the phase I study, the median age was 60 years (range, 43-85), the median number of prior therapies was 2 (range, 1-4), with all but 3 patients receiving prior bortezomib. The median number of cycles on therapy was 4 (1-12). Dose limiting toxicities including insomnia, restlessness, and psychosis were observed in two patients at dose level 6 (plerixafor 0.40 mg/kg and bortezomib 1.3 mg/m2). Therefore, 3 additional patients were enrolled at dose level 5b (plerixafor 0.32 mg/kg and bortezomib 1.3 mg/m2). There were no grade 4 toxicities. Grade 3 toxicities included lymphopenia (40%), hypophosphatemia (20%), anemia (10%), hyponatremia (10%), hypercalcemia (10%), and bone fracture due to myeloma bone disease (10%). Twenty-three patients were evaluable for response, including 1 (4%) complete response (CR), 1 (4%) very good partial response (VGPR), 1 partial remission (PR) and 2 (9%) MR, and 15 (65%) having stable disease with only 3 (13%) progressive disease (PD). In the phase II study, the median age was 63 (46-83). The median number of prior therapies was 2 (1-5), with 22 (66%) who have received prior bortezomib. The median number of cycles on therapy is 5 (1-24). The response rate included 5 VGPR (16%), 11 PR (35%) with an overall response rate of 51% and another 11 (35%) stable disease. Grade 3/4 toxicities included thrombocytopenia (68%), lymphopenia (6%), hypophosphatemia (2%), anemia (4%), infections (4%), hyponatremia (2%), hypercalcemia (2%) and neurological toxicity (2%). We also examined in vivo mobilization of plasma cells, CD34+ hematopoietic stem cells and other accessory bone marrow cells. Analysis of these samples showed rapid mobilization of plasma cells at 2 hours post-plerixafor with a rapid return to normal levels at 4 and 24 hours post plerixafor. CONCLUSIONS: The combination of plerixafor and bortezomib is generally well tolerated with minimal neuropathy or other toxicities seen to date. The responses observed are strongly encouraging with 51% ORR in this relapsed and refractory population. This study was supported by R01CA133799-01, and by Sanofi and Takeda Corporations. Disclosures Off Label Use: Plerixafor in myeloma. Azab:Verastem: Research Funding; Selexys: Research Funding; Karyopharm: Research Funding; Cell Works: Research Funding; Targeted Therapeutics LLC: Other: Founder and owner . Schlossman:Millennium: Consultancy. Richardson:Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; 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; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium Takeda: Membership on an entity's Board of Directors or advisory committees.

Description: Abstract 1943 Introduction: Plerixafor (Mozobil®), a potent CXCR4 inhibitor, is approved in combination with G-CSF to mobilize hematopoietic stem cells (HSCs) for autologous transplantation in multiple myeloma (MM) and non Hodgkin's lymphoma (NHL). Another area of investigation consists of exploring whether disruption of the CXCR4 pathway by plerixafor could potentiate the effect of chemotherapy in active disease. This study aimed to establish the maximum tolerated dose (MTD) of plerixafor in combination with bortezomib in patients who have active relapse/refractory MM. This was informed by preclinical studies showing that plerixafor induces de-adhesion of MM cells with sensitization to combination therapy with bortezomib in pre-clinical animal models. Methods: Eligibility criteria include: 1) patients with relapsed or relapsed/refractory MM with any prior lines of therapy including bortezomib, 2) measurable disease, 3) not receiving chemotherapy〉 3weeks, or biological/novel therapy for MM 〉 2 weeks. Patients with active disease received plerixafor at the recommended dose sc on days 1–6 of every cycle. Dose levels include 0.16, 0.24, 0.32, 0.40, and 0.48 mg/kg. Bortezomib was given at the recommended dose twice a week on days 3, 6, 10, and 13 every 21 days. Dose levels include 1.0 and 1.3 mg/m2. Bortezomib was given 60–90 minutes after plerixafor. Patients were assessed after every cycle. Patients who had response or stable disease went on to receive a total of 8 cycles without planned maintenance therapy. 4 dose levels were initially planned at a maximum of 0.24 mg/kg plerixafor. The protocol was then modified to include 3 higher doses of plerixafor, to further evaluate the hypothesis that higher doses may induce better chemosensitization. To examine the in vivo effect of plerixafor and bortezomib on de-adhesion of MM cells and other accessory cells of bone marrow, blood samples were obtained from patients at 0, 2, 4 and 24 hours post-plerixafor injection on days 1 and 3, and time points 0, 2, and 4 hours on days 6, 10 and 13 of cycle 1 and examined for the presence of plasma cells or CD34+ cells using flow cytometry. Results: Thirteen patients have been treated to date, three in each cohort with cohort 5 currently enrolling. The median age is 60, the median lines of prior therapy is 2. All of the patients received prior bortezomib. Three patients were assessed by light chain, two patients had extramedullary disease. The median number of cycles on therapy was 5 (1-8). None of the patients came off study due to toxicity. To date, there have been no dose-limiting toxicities. Overall, the combination is very well tolerated. Grade 3 possibly related toxicities include lymphopenia (30%), hypophosphatemia (15%), anemia (8%), and hyponatremia (8%). No grade 2 or higher neuropathy has been noted in these patients. Twelve patients are evaluable for response, including 1 (8%) complete remission (CR) and 1 (8%) minimal response (MR), with an overall response rate including MR of 2 (16%) in this relapsed/refractory population. In addition, 8 (66%) patients had stable disease (SD), and 2 (18%) had progressive disease (PD). We also examined the number of plasma cells, CD34+ HSCs, and other accessory bone marrow cells (including endothelial progenitor cells and plasmacytoid dendritic cells) in the peripheral blood. Analysis of these samples is ongoing, but preliminary data indicate de-adhesion of plasma cells. Conclusions: : The combination of plerixafor and bortezomib is very well tolerated with minimal neuropathy or other toxicities. The responses observed are encouraging in this relapsed/refractory population. The ability to demonstrate transient de-adhesion of MM cells and accessory cells in vivo indicates that these cells can be separated from their protective stromal environment which may make them more sensitive to chemotherapy. This study was supported by R01CA133799-01, and by Genzyme. Disclosures: Ghobrial: Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Munshi:Millennium Pharmaceuticals: Honoraria, Speakers Bureau. Anderson:Millennium Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Richardson:Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees.

Description: Abstract 2727 Poster Board II-703 INTRODUCTION: This study aimed to determine activity and safety of weekly bortezomib and rituximab in patients with relapsed/refractory Waldenstrom's Macroglobulinemia (WM). METHODS: Patients who had at least one previous therapy were eligible. All patients received bortezomib IV weekly at 1.6 mg/m2 on days 1, 8, 15, q 28 days x 6 cycles, and rituximab 375 mg/m2 weekly on cycles 1 and 4. Primary endpoint was the percent of patients with at least a minor response. RESULTS: Thirty-seven patients were treated. Majority of patients (78%) completed treatment per protocol. At least minimal response (MR) or better was observed in 81% (95% CI: [65,92]) with 2 patients (5%) in complete remission (CR)/near CR, 17 (46%) in partial response (PR), and 11(30%) in MR. The median time to progression was 16.4 months (95% CI, 11.4–21.1). Death occurred in 1 patient due to viral pneumonia. The most common grade 3 and 4 therapy related adverse events included reversible neutropenia in 16%, anemia in 11%, and thrombocytopenia in 14%. Grade-3 peripheral neuropathy occurred in only 2 patients (5%). The median event-free survival (EFS) is 12 months (95% CI, 11–20) with estimated 12 month and 18 month EFS of 49% (95% CI: [31, 67%]) and 38% (95% CI: [20, 56%]). The median overall survival has not been reached. CONCLUSIONS: The combination of weekly bortezomib and rituximab showed significant activity and minimal neurological toxicity in patients with relapsed WM. Disclosures: Ghobrial: Millennium: Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau. Anderson:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Richardson:Millennium Pharmaceuticals, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Johnson and Johnson: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keryx: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Treon:Millennium: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding, Speakers Bureau; Genentech: Honoraria, Research Funding, Speakers Bureau. Matous:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Cephalon: Membership on an entity's Board of Directors or advisory committees.

Description: Abstract 2705 INTRODUCTION: This study aimed to determine the safety and maximum tolerated dose of the combination of everolimus and rituximab, or everolimus, bortezomib, and rituximab in relapsed and/or relapsed/refractory Waldenstrom Macroglobulinemia. This trial was based on our preclinical studies that demonstrated synergistic activity of everolimus and bortezomib with rituximab in WM cell lines, and based on our favorable clinical experience with everolimus as single agent in the treatment of WM. METHODS: Eligibility criteria include: 1) patients with relapsed or relapsed/refractory WM with any number of prior lines of therapy, including everolimus and bortezomib 2) not completely refractory to rituximab 3) measurable disease by monoclonal IgM protein in the serum and lymphoplasmacytic cells in the bone marrow, 4) Not receiving chemotherapy 〉 3 weeks, or biological/novel therapy for WM 〉 2 weeks. A cycle is 28 days and a total of 6 cycles are given, followed by everolimus maintenance for 2 years. Two stages with a total of four dose levels were planned. In stage A, patients received everolimus at the recommended dose orally daily for 28 days and rituximab at the recommended dose IV on days 1, 8, 15, and 22 every 28 days at cycle 1 and 4 only. In stage B, patients received everolimus at the recommended dose orally daily for 28 days, bortezomib at the recommended dose IV on days 1, 8, 15 every 28 days, and rituximab at the recommended dose IV on days 1, 8, 15, and 22 every 28 days at cycle 1 and 4 only. Patients were assessed for response after every cycle. Subjects who had a response continued on therapy for a total of 6 cycles, and then continued on to maintenance therapy with everolimus alone until progression (or for a maximum of 24 months). Because of the potential of an IgM flare after rituximab, patients who showed an increase in IgM after rituximab in the first 3 months were not deemed as having progressive disease unless they showed evidence of clinical progression. To examine the in vivo effect of everolimus, bortezomib, and rituximab, peripheral blood samples were obtained from patients on days 1, 8, 15, and 22 at cycle 1; and on day 1 only at all subsequent cycles. RESULTS: Twenty-three patients were enrolled in this phase I clinical trial from April 2009 to July 2011. The median age is 61 (range, 52–73) yrs and the median lines of prior therapy is 2 (range, 1–8) with all patients receiving prior rituximab and 12 (52%) receiving prior bortezomib. The median number of cycles on therapy was 3.5 (range, 0–15). Overall, this combination therapy is very well tolerated. Grade 4 toxicities included: neutropenia (8.7%), leukopenia (4.3%), thrombocytopenia (17.4%), lymphopenia (4.3%) and hypertriglyceridemia (4.3%). Grade 3 toxicities included: neutropenia (21.7%), leukopenia (26.1%), anemia (13%), lymphopenia (17.4%), pneumonitis (4.3%), SGPT (4.3%), neuropathy (4.3%), Herpes zoster reactivation (4.3%), hyperglycemia (4.3%) and hypernatremia (4.3%). 1 patient discontinued therapy due to grade 3 anemia. Nineteen patients are currently evaluable for response, including 1 (5%) very good partial response (VGPR) and 9 (47%) minimal response (MR), for an overall response rate including MR of 10/19 (53%) in this relapsed/refractory population. Furthermore, overall response including MR in stage A (everolimus/rituximab) was 2/6 (33%) and 8/13 (62%) in stage B (everolimus/bortezomib/rituximab). Additionally, 9 (39%) patients achieved stable disease, and 4 (17%) are early on therapy and not been yet assessed. CONCLUSIONS: The combination of everolimus, bortezomib, and rituximab is generally well tolerated, and importantly no grade 3/4 neuropathy was seen. Moreover, no dose limiting toxicities were observed even at the maximum dose evaluated. The responses observed to date in this relapsed/refractory population are encouraging. Based on the safety of this phase I study, the phase II study of two arms, everolimus/rituximab for low risk patients and everolimus/bortezomib/rituximab for intermediate and high risk patients is underway. Disclosures: Ghobrial: Bristol-Myers Squibb: Research Funding; Millennium: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Noxxon: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: Bortezomib and everolimus in WM. Anderson:Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees; Onyx: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Acetylon: Membership on an entity's Board of Directors or advisory committees. Richardson:Millennium: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees. Treon:Millennium: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees.

Description: Abstract 3952 Introduction: This study aimed to determine the safety and activity of panobinostat (LBH589) in patients with relapsed or relapsed/refractory Waldenstrom Macroglobulinemia (WM). This was based on our preclinical studies showing that panobinostat induces significant activity in cell lines and patient samples. Methods: Eligibility criteria include: 1) patients with relapsed or relapsed/refractory WM with any prior lines of therapy, 2) measurable disease and symptomatic disease, 3) off prior chemotherapy〉 3 weeks, or biological/novel therapy for WM 〉 2 weeks. Patients received panobinostat at 30 mg three times a week (Mondays, Wed and Fridays). Patients were assessed after every cycle for the first 6 cycles and then every 3 months thereafter. Subjects who had response or stable disease were allowed to continue on therapy until disease progression or unacceptable toxicity. A planned restaging was performed at the end of cycle 6 including CT scans and bone marrow biopsies. Results: Twenty-seven patients have been enrolled to date. The median age is 62 years (47-80), the median lines of prior therapy is 3 (range, 1–7). All of the patients received prior rituximab. The median hemoglobin at screening is 10.3 g/dL (range 8.2–14.3), the median IgM M-spike by protein electropheresis at study entry is 1.9 g/dL (range, 0.63–5.1), and median serum IgM at baseline is 3610 mg/dL (range, 804- 10, 300). The median bone marrow involvement at enrollment was high for patients with WM, 50%, range (5-95%), with more than 10 patients having 70% or higher bone marrow involvement at baseline. The median number of cycles on therapy is 4 (range 1 – 12). 4 of the patients came off due to toxicity. Minimal response (MR) or better has been achieved in 15 (60%) of patients, with 6 (24%) PR, 9 (36%) MR. In addition, 9 (36%) patients achieved stable disease and 1 (4%) showed progression. The median decrease in IgM is 1020 mg/dL (0- 3970 decrease in IgM) with a median % decrease of 37.13%. Responses were prompt. The median time to first response was 2 cycles (range, 2–4). Bone marrow biopsies at the end of study (or at 6 months follow up) are available on 7 patients, of which 3 showed a significant decrease in bone marrow involvement and 4 showed stable involvement. The 4 patients who had stable bone marrow disease showed 1 PR and 3 MR responses by paraprotein level. Grade 3 and 4 toxicities include 4 (15%) cases of anemia including 1 case of hemolytic anemia, 1 (3%) case of grade 4 leucopenia (but the patient had grade 3 leucopenia at baseline), 7 (26%) of neutropenia, 14 (52%) of thrombocytopenia, 1 (4%) grade 3 GI bleed due to thrombocytopenia, 1 (3%) Grade 4 hyperglycemia and 1 (3%) grade 3 syncope and 3 (27%) grade 3 fatigue. The most common grade 2 toxicities were thrombocytopenia, anemia, and fatigue. There were 5 (20%) cases of asymptomatic pulmonary infiltrates of ground glass opacity observed on routine CT scans in follow up. Of these, 3 came off study for other reasons not related to the pulmonary infiltrates, 1 received a course of corticosteroids and had improvement of infiltrates, and 1 had dose reduction of therapy. All patients except for 2 have been dose reduced due to thrombocytopenia, fatigue, diarrhea, or anemia. Dose reductions include 25 mg three times a week, 20 mg three times a week and 20 mg three times every other week. The protocol was amended to allow a starting dose of 25 mg three times a week, which is better tolerated than 30 mg in this patient population. Conclusions: Panobinostat is an active therapeutic agent in patients with relapsed or refractory WM, with an overall response rate of 60% in patients with relapsed or refractory WM. The dose schedule of 25 mg three times a week is better tolerated in this patient population. Further studies to include this agent in combination with rituximab or bortezomib are being evaluated. Disclosures: Ghobrial: Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Anderson:Millennium Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Richardson:Keryx Biopharmaceuticals: Honoraria. Treon:Millennium Pharmaceuticals, Genentech BiOncology, Biogen IDEC, Celgene, Novartis, Cephalon: Consultancy, Honoraria, Research Funding; Celgene Corporation: Research Funding; Novartis Corporation: Research Funding; Genentech: Consultancy, Research Funding.

Description: Background: CXCR4 is a chemokine receptor overexpressed in more than 20 tumor types, including malignant plasma cells. The CXCR4/CXCL12 (SDF-1) axis has been known for many years as a critical regulator of tumor proliferation, cell, as well as migration into and out of the bone marrow. Ulocuplumab (BMS- 936564) is a first in class, fully human IgG4 monoclonal anti-CXCR4 antibody which inhibits the binding of CXCR4 to CXCL12. This study aimed to determine the safety, tolerability, pharmacokinetics, pharmacodynamics, and clinical activity of Ulocuplumab alone and in combination with lenalidomide plus dexamethasone (Len-Dex), or in combination with bortezomib plus dexamethasone (Bor-Dex) in subjects with relapsed/refractory multiple myeloma. Patients / Methods: Patients were eligible for this trial if they were 18 years of age or older with relapsed or relapsed/refractory multiple myeloma after having received at least 2 prior lines of treatment. Patients in whom who both lenalidomide and bortezomib had failed were not excluded from re-treatment with the same regimen. Patients were enrolled at four cancer centers in the U.S. from October 2011 to March 2014. Ulocuplumab (1, 3 and 10 mg/kg) was dose escalated with a 3-plus-3 design with doses of Len-Dex or Bor-Dex to identify maximum tolerated dose (MTD). Ulocuplumab was given weekly in combination with either 25mg lenalidomide on days 1-21 and 40mg oral dexamethasone on days 1, 8, 15, and 22 of the 28-day cycles on Arm A or 1.3 mg/m2 bortezomib on days 1, 4, 8, and 11 and 20mg oral dexamethasone on days 1, 2, 4, 5, 8, 9, 11, and 12 of the 21-day cycles on Arm B since cycle 2. The primary endpoints for this study were dose-limiting toxicities. Other key safety endpoints included incidence of adverse events (AE), AEs leading to discontinuation, SAEs, deaths, and laboratory abnormalities. The efficacy endpoints included overall responses, duration of response, and time to response. Responses were assessed using the IMWG criteria. Results: Forty-six patients were enrolled (median age, 60 years; range, 53-67). The median number of prior therapies was 3 (range, 1-11), with 70.0% of patients having received ≥ 3 lines of treatment. Ulocuplumab was escalated to a maximum of 10 mg/kg without reaching MTD. The most common treatment-related adverse events of any grade were neutropenia (13 patients, 43.3%), diarrhea (10 patients, 33.3%), thrombocytopenia (10 patients, 33.3%), and fatigue (7 patients, 23.3%) in Arm A; and thrombocytopenia (6 patients, 37.5%), fatigue (4 patients, 25.0%) and anemia (4 patients, 25.0%) in Arm B. The overall response rate (≥ partial response) for all subjects in escalation and expansion was 44.4% (20/45). The median time to response was 1.5 months (range 0.4-7.8 months) for Arm A and 1.0 month (range 0.5-3.7 months) for Arm B, respectively. Of note, the combination of Ulocuplumab with Len-Dex showed a high response rate of 55.2% and a clinical benefit rate ( ≥ minimal response) of 72.4%, including patients who have been previously treated with lenalidomide. Conclusion: This study shows that the blockade of the CXCR4-CXCL12 axis by Ulocuplumab is safe and has an encouraging response rate of over 50% in the Len-Dex arm of patients with relapsed/refractory myeloma. The distinct mechanisms of action of this antibody, as well as its non- cross resistance with currently approved approaches, make it a new class of anti-myeloma drug that warrants further exploration and evaluation in future clinical trials. Disclosures Ghobrial: Takeda: Consultancy; Celgene: Consultancy; BMS: Consultancy; Janssen: Consultancy. Richardson:Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; BMS: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: 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; Amgen: Membership on an entity's Board of Directors or advisory committees. Anderson:Celgene: Consultancy; Takeda Millennium: Consultancy; Bristol Myers Squibb: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; Oncopep: Equity Ownership; C4 Therapeutics: Equity Ownership. Becker:GlycoMimetics: Research Funding.

Description: Key Points Carfilzomib, rituximab, and dexamethasone (CaRD) produce overall and CR/VGPR responses in 87% and 36% of frontline WM patients, respectively. CaRD activity was not impacted by MYD88 and CXCR4 mutations and represents a neuropathy-sparing option for treating WM patients.

Description: Introduction This study aimed to determine the safety and activity of plerixafor (CXCR4 inhibitor) in combination with bortezomib as a chemosensitization strategy in multiple myeloma (MM). The phase I portion of this study was to determine the maximum tolerated dose (MTD). The phase II portion was designed to assess the toxicity profile and the proportion of overall confirmed response (CR + PR). This was based on preclinical studies demonstrating that plerixafor (Mozobil, Sanofi Corporation, MA) induces de-adhesion of MM cells and sensitization to bortezomib in preclinical animal models. Methods Eligibility criteria included: 1) patients with relapsed or relapsed/refractory MM with 1–5 prior lines of therapy including bortezomib (unless patients were refractory to bortezomib), 2) measurable disease, 3) not receiving chemotherapy 〉 3 weeks, or biological therapy for MM 〉 2 weeks prior to study treatment. Phase I included eight cohorts with different doses and two treatment schedules. In cohorts 1–5, patients received plerixafor at the recommended dose subcutaneously (sq) on days 1–6 of each cycle and bortezomib at the recommended dose twice a week on days 3, 6, 10, and 13 every 21 days. Cohort 5b–7 plerixafor was given at the recommended dose sq on days 1, 3, 6, 10, and 13 and bortezomib was given at the recommended dose twice a week on days 3, 6, 10, and 13 every 21 days. For the phase II portion patients received plerixafor at the MTD, 320 mcg/kg sq on days 1, 2, 3, 6, 10, and 13. Bortezomib was given 1.3 mg/m2 sq twice a week on days 3, 6, 10, 13, every 21 days. Dexamethasone was given at 40mg on days of Bortezomib. Patients in both cohorts were assessed after every cycle by IMWG criteria. Patients who had a response or stable disease went on to receive a total of 8 cycles with maintenance therapy for patients with at least a minimal response (MR). Peripheral blood samples were obtained from the patients in the phase I portion of trial at 0, 1, 2, 3, 4 and 24 hours post-dose on days 1 and 3, and time points 0, 2, and 4 hours post-dose on days 6, 10 and 13 of cycle 1. Results Twenty-five patients were enrolled in the phase I portion of trial from June 2009 to May 2011. Median age was 60 years (range, 44–85) and median lines of prior therapy were 2 (range, 1–4) with all but 3 patients receiving prior bortezomib. The median number of cycles on therapy was 3 (1–11). Dose limiting toxicities including insomnia, restlessness, and psychosis were observed in two patients at dose level 6 (plerixafor 0.40 mg/kg and bortezomib 1.3 mg/m2). To further explore the safety of maximum tolerated dose, three additional patients were enrolled at dose level 5b (plerixafor 0.32 mg/kg and bortezomib 1.3 mg/m2). There were no grade 4 toxicities. Grade 3 toxicities included lymphopenia (40%), hypophosphatemia (20%), anemia (10%), hyponatremia (10%), hypercalcemia (10%), and bone fracture due to myeloma bone disease (10%). In the phase II portion, eleven patients have been treated to date. The median age is 65 (56-80), the median lines of prior therapy were 2 (1-4). The median number of cycles on therapy was 4 (1-8). Grade 4 toxicities include lymphopenia (10%) and thrombocytopenia (20%). Grade 3 toxicities include anemia (10%), thrombocytopenia (10%), lymphopenia (20%), hyperglycemia (10%), and hypophosphatemia (10%). Ten patients are evaluable for response, including 1(10%) very good partial response (VGPR) and 3 (30%) partial response (PR), with an overall response rate (VGPR + PR) of 4 (40%) in this relapsed/refractory population. In addition, 4 (40%) patients had stable disease (SD), and 2 (20%) had progressive disease (PD). We also examined in vivo mobilization of plasma cells, CD34+ hematopoietic stem cells and other accessory bone marrow cells. Analysis of these samples showed rapid mobilization of plasma cells at 2 hours post-plerixafor with a rapid return to normal levels at 4 and 24 hours post plerixafor. Similar results were observed on days 1 and 3. Conclusions The combination of plerixafor and bortezomib was generally well tolerated in this study, with minimal neuropathy or other toxicities seen to date. The responses observed are encouraging with 40% PR or better in this relapsed and refractory population including prior bortezomib therapy. This study was supported by R01CA133799-01, and by Sanofi and Millennium/Takeda Corporations. Disclosures: Ghobrial: Onyx: Membership on an entity’s Board of Directors or advisory committees; BMS: Membership on an entity’s Board of Directors or advisory committees; BMS: Research Funding; Sanofi: Research Funding; Novartis: Membership on an entity’s Board of Directors or advisory committees. Munshi:Celgene: Consultancy; Novartis: Consultancy; Millennium: Consultancy. Anderson:celgene: Consultancy; onyx: Consultancy; gilead: Consultancy; sanofi aventis: Consultancy; oncopep: Equity Ownership; acetylon: Equity Ownership. Richardson:Millenium: Consultancy; Celgene: Consultancy; Johnson & Johnson: Consultancy; Bristol-Myers Squibb: Consultancy; Novartis: Consultancy.

Description: Abstract 3752 Poster Board III-688 INTRODUCTION This study aimed to determine activity and safety of weekly bortezomib and rituximab in patients with untreated Waldenstrom's Macroglobulinemia (WM). Prior studies using twice a week bortezomib in this population showed high responses, but significant neuropathy. METHODS Patients who had symptomatic WM and were not previously treated were eligible. All patients received bortezomib IV weekly at 1.6 mg/m2 on days 1, 8, 15, q 28 days x 6 cycles, and rituximab 375 mg/m2 weekly on cycles 1 and 4. Dexamethasone was not added. Primary endpoint was the percent of patients with at least a minor response. Patients were encouraged to receive herpes zoster prophylaxis but it was not mandated. RESULTS Twenty-six patients were treated. At least minimal response or better was observed, assessed using serum protein electropheresis, in 24/26 cases (92%) with 2 patients (8%) in complete remission (CR)/near CR, 15 (54%) in partial response (PR), and 7(27%) in minimal response (MR). Two patients (8%) had stable disease. By using IgM by nephlometry, all 26 patients (100%) had at least a minor response, with 2 (8%) CR, 15 (58%) in PR and 9 (35%) with minor response. The median time of follow up is 11.2 months (range, 3-18.6). To date, six (23%) patients have developed progressive disease or required a new therapy. A single patient has died due to disease progression. The median progression-free survival and overall survival have not been reached. The most common grade 3 and 4 therapy related adverse events included anemia in 3 patients, lymphopenia in 2 patients; neutropenia, leucopenia, thrombocytopenia, pneumonia, fatigue, allergic reaction and nausea and vomiting in 1 patient for each. Five patients developed grade 2 peripheral neuropathy including 4 did who did not have neuropathy at baseline. It required dose reductions in cycles 4 and 5 and these neuropathies resolved to grade 1 or less with follow up. One case developed grade 1 herpes zoster reactivation in cycle 1. CONCLUSIONS The combination of weekly bortezomib and rituximab showed significant activity and minimal neurological toxicity in patients with untreated WM. Disclosures: Ghobrial: Millennium: Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau. Anderson:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Richardson:Keryx Biopharmaceuticals: Honoraria. Treon:Millennium: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding, Speakers Bureau; Genentech: Honoraria, Research Funding, Speakers Bureau. Matous:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Cephalon: Membership on an entity's Board of Directors or advisory committees.