ALBERT

Description: Background: Survival of patients (pts) with multiple myeloma (MM) decreases with increased age (Pulte, Oncologist, 2011). In addition, MM pts with advanced disease who have exhausted treatment (Tx) with novel agents have a poor prognosis (Kumar, Leukemia, 2012). Pomalidomide (POM) is a new oral agent with antimyeloma, stromal cell inhibitory, and immune modulatory effects (Quach, Leukemia, 2010; Mark, Leuk Res, 2014). In the pivotal MM-003 trial, POM in combination with low-dose dexamethasone (LoDEX) demonstrated significant progression-free survival (PFS) and overall survival (OS) benefits vs. high-dose dexamethasone, with a tolerable safety profile in refractory or relapsed and refractory MM (RRMM; Dimopoulos, Blood, 2013). In MM-003, significant PFS and OS benefits with POM + LoDEX Tx were seen in different age groups; tolerability and dose intensity were not affected by age (Weisel, Blood, 2013). STRATUS is a multicenter, single-arm, open-label, European, phase 3b trial to further evaluate safety and efficacy of POM + LoDEX in a large pt population. This analysis examines outcomes by age (≤ 65 vs. 〉 65 yrs, and ≤ 70 vs. 〉 70 yrs). Methods: Eligible pts had refractory or relapsed and refractory disease (progressive disease [PD] during or within 60 days of last line of Tx), having previous BORT and LEN failure and adequate prior alkylator therapy as defined in study protocol. Pts must have been refractory to the last prior Tx line. Pts with Eastern Cooperative Oncology Group performance status 〉 2 were excluded. Pts received 28-day cycles of POM 4 mg D1-21 + DEX 40 mg (20 mg for pts aged 〉 75 yrs) once weekly. All pts received thromboprophylaxis with low-dose aspirin, low-molecular-weight heparin, or equivalent based on clinical recommendations. Tx continued until PD or unacceptable toxicity. The primary endpoint was safety; the secondary endpoints included POM exposure, overall response rate (ORR; ≥ partial response), duration of response (DOR), PFS, and OS. Outcomes were analyzed by pt age at baseline (≤ 65 vs. 〉 65 yrs, and ≤ 70 vs. 〉 70 yrs). Results: As of March 17th, 2014, a total of 456 pts have been enrolled, and 452 had received POM + LoDEX; 48% were aged ≤ 65 yrs, 52% were 〉 65 yrs, 71% were ≤ 70 yrs, and 29% were 〉 70 yrs. Pts were heavily pretreated (median 4-5 prior Tx depending on age subgroup). Median follow-up was 6.8 mos. Younger pts (≤ 65 yrs) were more likely to have better renal function (creatinine clearance ≥ 60 mL/min; 80%) than those aged 〉 65 (49%). Median relative dose intensity was similar independent of age (range, 0.95-0.97 mg/day). The most common grade (Gr) 3-4 treatment-emergent adverse events (TEAEs) across age groups were neutropenia, anemia, thrombocytopenia, and pneumonia (Table). Gr 3-4 deep vein thrombosis (DVT) with prophylaxis was 1% in each subgroup. Discontinuations of POM due to TEAEs were low in pts aged ≤ 65 (0.9%), 〉 65 (3.0%), ≤ 70 (1.3%), and 〉 70 (3.8%) yrs. Outcomes by age are summarized in the Table. ORR was consistent for pts aged ≤ 65 (38%), 〉 65 (32%), ≤ 70 (35%), and 〉 70 (34%) yrs; DORs were 5.1, 6.8, and 5.8 mos and not estimable (NE) in these pt populations, respectively. Median PFS and median OS were similar across all age groups (PFS range, 4.0-4.9 mos, OS range, 10.6-11.5 mos). Conclusions: The data reported here further demonstrate the tolerability and efficacy of POM + LoDEX in pts with RRMM in the age subgroups analyzed (≤ 65 vs. 〉 65 yrs and ≤ 70 vs. 〉 70 yrs). Safety profiles were consistent, while dose intensity was similar across age groups. PFS, OS, and response rates were comparable with those previously reported in trials of POM + LoDEX in pts with RRMM and reinforce 4 mg POM as an appropriate starting dose irrespective of age. These data support POM + LoDEX as a standard Tx option for pts with refractory or RRMM regardless of age. Table 1. Age ≤ 65 yrs (n = 215) Age 〉 65 yrs (n = 237) Age ≤ 70 yrs (n = 319) Age 〉 70 yrs (n = 133) Grade 3-4 TEAEs, % Neutropenia Anemia Thrombocytopenia Pneumonia 38 30 22 13 41 24 16 10 38 29 21 11 44 23 15 11 Grade 3-4 EOI, % DVT/PE PN 1

Description: Cell adhesion in the multiple myeloma (MM) microenvironment is a mechanism by which MM plasma cells escape the effects of therapy and survive. To improve clinical strategies and overcome drug resistance, approaches directed to both MMPCs and bone marrow microenvironment are under investigation. Here, we examined the cell membrane protein Junctional adhesion molecule-A (JAM-A) as a clinical biomarker and novel therapeutic target for MM. We evaluated JAM-A expression by real time PCR (RT-PCR), flow cytometry and immunofluorescence microscopy in 132 MM patients at different stages and various MM cell lines. Next, we measured the concentrations of soluble JAM-A from MM and healthy subjects sera by enzyme linked immune assay (ELISA). We investigated JAM-A functionally in vitro and in vivo by transient gene silencing (siRNA) and with blocking antibodies. Patient-derived plasma cells (MMPCs) expressed increased JAM-A expression levels when compared to control PC from healthy individuals. Elevated JAM-A expression correlated with poor prognosis (Figure 1A,B). Furthermore, soluble JAM-A was significantly increased in MM patient sera when compared to healthy subjects. Additionally, MM cell lines showed high expression of both membrane and cytoplasmic JAM-A. Consequently, inhibition of JAM-A using specific siRNA treatment resulted in diminished tumorigenic potential, including decreased colony formation, chemotaxis and migration. Importantly, treatment of luciferase+RPMI-8226 MM bearing NSG with a JAM-A blocking monoclonal antibody reduced significantly MM progression and dissemination in vivo when compared to MM bearing mice that received an non-specific isotype control antibody (Figure 1C). Conclusively, our data suggest that JAM-A can serve as a biomarker of malignancy in MM patients. Soluble plasma JAM-A could contribute to serum-based clinical stratification. Furthermore, therapeutic targeting of JAM-A appears attractive for clinical translation. Figure 1 Figure 1. Disclosures Einsele: Celgene: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria.

Description: Vascular endothelial growth factor165 (VEGF165) and semaphorin3A (SEMA3A) elicit pro- and antiangiogenic signals respectively in endothelial cells (ECs) by binding to their receptors VEGFR-2, neuropilin-1 (NRP1), and plexin-A1. Here we show that the VEGF165-driven angiogenic potential of multiple myeloma (MM) ECs is significantly higher than that of monoclonal gammopathy of undetermined significance (MGUS) ECs (MGECs) and human umbilical vein (HUV) ECs. This is probably due to a constitutive imbalance of endogenous VEGF165/SEMA3A ratio, which leans on VEGF165 in MMECs but on SEMA3A in MGECs and HUVECs. Exogenous VEGF165 induces SEMA3A expression in MGECs and HUVECs, but not in MMECs. Moreover, by counteracting VEGF165 activity as efficiently as an anti-VEGFR-2 antibody, exogenous SEMA3A restrains the over-angiogenic potential of MMECs. Our data indicate that loss of endothelial SEMA3A in favor of VEGF165 could be responsible for the angiogenic switch from MGUS to MM.

Description: Multiple myeloma (MM) plasma cell (MMPC) interactions with the microenvironment control MMPC growth, survival, drug-resistance and intra- and extramedullary dissemination. Dissemination of MMPCs through bone marrow niches and in extra-medullary sites is an active process of invasion involving bone marrow endothelial cells, multiple adhesion molecules and chemokine receptors. Since enhanced angiogenesis characterizes MM, we investigated whether junctional adhesion molecule-A (JAM-A) mediated interactions between MM bone marrow endothelial cells (MMECs) and MMPCs impact disease progression. To this end, we analyzed JAM-A expression levels in MMECs of 312 MM patients in two independent cohorts with flow cytometry, namely 111 newly diagnosed (NDMM) and 201 relapsed/refractory (RRMM) and compared them to 36 monoclonal gammopathy of undetermined significance (MGUS) and healthy subjects. To corroborate our data and investigate at a gene-expression level the prognostic value of deregulated genes (FDR

Description: Background: Treatment (Tx) with novel agents, including lenalidomide (LEN) and bortezomib (BORT), has extended survival of patients (pts) with multiple myeloma (MM); however, pts who have relapsed on or become refractory to Tx have significantly shortened overall survival (OS) and poorer outcomes (Kumar, Leukemia, 2012). Renal impairment (RI) occurs frequently, in approximately 20% to 40% of MM pts (Kastritis, Haematologica, 2007), and is a leading cause of death in this pt population (Korbet, J Am Soc Nephrol, 2006). In the phase 3 MM-003 trial, pomalidomide plus low-dose dexamethasone (POM + LoDEX) significantly extended progression-free survival (PFS) and OS vs. high-dose dexamethasone in pts in whom BORT and LEN Tx failed, including those with moderate RI (creatinine clearance [CrCl] 〈 60 mL/min; Weisel, Blood, 2013). STRATUS is a multicenter, single-arm, open-label, European, phase 3b trial to further evaluate safety and efficacy of POM + LoDEX in pts with refractory or relapsed and refractory MM (N = 456), including those with moderate RI. Methods: Pts must have had refractory or relapsed and refractory disease (progressive disease [PD] during or within 60 days of last line of Tx), at least 2 prior therapies, BORT and LEN failure after ≥ 2 cycles of each (alone or in combination), and adequate prior alkylator therapy as defined in study protocol. Pts must have been refractory to their last line of Tx; pts with CrCl 〈 45 mL/min were excluded. POM was administered 4 mg D1-21/28-day cycle and LoDEX 40 mg/day (20 mg for pts aged 〉 75 yrs) on D1, 8, 15, and 22 until PD or unacceptable toxicity. All pts received thromboprophylaxis with low-dose aspirin, low-molecular-weight heparin, or equivalent based on clinical recommendations. The primary endpoint was safety, and secondary endpoints included POM exposure, overall response rate (ORR; ≥ partial response), duration of response (DOR), PFS, and OS. For this analysis, pts were retrospectively grouped by baseline CrCl (〈 60 mL/min vs. ≥ 60 mL/min). Results: A total of 456 pts have been enrolled, of whom 452 received POM + LoDEX and 165 (36%) had moderate RI (CrCl 〈 60 mL/min). After a median follow-up of 6.8 mos, the most frequently reported grade (Gr) 3-4 treatment-emergent adverse events (TEAEs) in pts with moderate RI vs. without moderate RI (CrCl ≥ 60 mL/min) were neutropenia (39% vs. 40%), anemia (33% vs. 24%), and thrombocytopenia (19% vs. 19%); the most common Gr 3-4 nonhematologic TEAEs were pneumonia (12% vs. 11%), fatigue (6% vs. 4%), and hypercalcemia (4% vs. 4%), respectively. Only 2% of pts in each respective renal subgroup discontinued POM due to Tx-related TEAEs. Gr 3-4 renal toxicities were similar in both subgroups: acute renal failure occurred in 3% of pts with moderate RI and 2% of pts without moderate RI; blood creatinine increased in 2% and 1% of pts, respectively. Overall, Gr 3-4 deep vein thrombosis (DVT), pulmonary embolism (PE), and peripheral neuropathy (PN) were infrequent independent of renal status (Table). Median relative POM dose intensity was similar between subgroups (0.95 in pts with moderate RI vs. 0.96 in pts without moderate RI). In pts with moderate RI vs. without moderate RI, ORR was 35% vs. 34%, median DOR was 5.8 mos vs. 6.5 mos, median PFS was 3.7 vs. 4.6 mos, and median OS was 9.3 vs. not reached, respectively (Table). The 1-yr OS was 33% for pts with moderate RI vs. 53% for pts without moderate RI. Conclusions: POM + LoDEX has acceptable safety and efficacy profiles comparable to those observed in the pivotal MM-003 trial. Tolerability was consistent across renal function subgroups, with few discontinuations due to adverse events. In addition, responses to POM + LoDEX were similar between pts, irrespective of renal function. POM is currently being prospectively evaluated in pts with severe RI in the MM-008 (US) and MM-013 (EU) trials. Table.With Moderate RICrCl 〈 60 mL/min (n = 162)Without Moderate RICrCl ≥ 60 mL/min(n = 290)Grade 3-4 TEAEs, %Neutropenia Anemia Thrombocytopenia Pneumonia39 33 19 1240 24 19 11Grade 3-4 EOI, %DVT/PE PN2 20 1Efficacy(n = 165)(n = 291)ORR (≥ PR), % (95% CI) Median DOR (95% CI), mos Median PFS (95% CI), mos Median OS (95% CI), mos35 (27.9-43.0) 5.8 (3.7-NE) 3.7 (2.9-5.2) 9.3 (6.3-11.5)34 (28.9-40.1) 6.5 (4.7-7.9) 4.6 (3.7-5.6) NR (10.9-NR) EOI, events of interest; NE, not estimable, NR, not reached. Disclosures Weisel: Celgene Corporation: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Onyx: Consultancy, Honoraria; BMS: Consultancy; Noxxon: Consultancy. Dimopoulos:Celgene: Consultancy, Honoraria. Cavo:Celgene: Consultancy, Honoraria, Speakers Bureau. Ocio:Celgene Corporation: Honoraria, Research Funding. Palumbo:Bristol-Myers Squibb: Consultancy, Honoraria; Genmab A/S: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Janssen-Cilag: Consultancy, Honoraria; Millennium Pharmaceuticals, Inc.: Consultancy, Honoraria; Onyx Pharmaceuticals: Consultancy, Honoraria; Array BioPharma: Honoraria; Amgen: Consultancy, Honoraria; Sanofi: Honoraria. Delforge:Celgene Corp: Honoraria; Janssen: Honoraria. Oriol:Celgene Corporation: Consultancy. Goldschmidt:Celgene Corp: Consultancy, Honoraria, Speakers Bureau. Miller:Celgene Corporation: Employment, Equity Ownership. Peluso:Celgene: Employment. Sternas:Celgene Corp: Employment, Equity Ownership. Zaki:Celgene : Employment, Equity Ownership. Moreau:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Description: To assess whether the progression of plasma cell tumors is accompanied by angiogenesis and secretion of matrix-degrading enzymes, bone marrow biopsy specimens from 20 patients with monoclonal gammopathy of undetermined significance (MGUS), 18 patients with nonactive multiple myeloma (MM), and 26 patients with active MM were evaluated for their angiogenic potential and matrix-metalloproteinase (MMP) production. A fivefold increase of the factor VIII+microvessel area was measured by a planimetric method of point counting in the bone marrow of patients with active MM as compared with nonactive MM and MGUS patients (P 〈 .01). When serum-free conditioned media (CM) of plasma cells isolated from the bone marrow of each patient were tested in vivo for their angiogenic activity in the chick embryo chorioallantoic membrane (CAM) assay, the incidence of angiogenic samples was significantly higher (P〈 .01) in the active MM group (76%) compared with nonactive MM (33%) and MGUS (20%) groups. Moreover, a linear correlation (P 〈 .01) was found between the extent of vascularization of the bone marrow of a given patient and the angiogenic activity exerted in the CAM assay by the plasma cells isolated from the same bone marrow. In vitro, a significantly higher fraction of the plasma cell CM samples from the active MM group stimulated human umbilical vein endothelial cell (HUVEC) proliferation (53%, P 〈 .01), migration (42%, P 〈 .05), and/or monocyte chemotaxis (38%,P 〈 .05) when compared with nonactive MM and MGUS groups (ranging between 5% and 15% of the samples). Also, immunoassay of plasma cell extracts showed significantly higher (P 〈 .01) levels of the angiogenic basic fibroblast growth factor (FGF)-2 in the active MM patients than in nonactive MM and MGUS patients (153 ± 59, 23 ± 17, and 31 ± 18 pg FGF-2/100 μg of protein, respectively). Accordingly, neutralizing anti–FGF-2 antibody caused a significant inhibition (ranging from 54% to 68%) of the biological activity exerted on cultured endothelial cells and in the CAM assay by plasma cell CM samples from active MM patients. Finally, in situ hybridization of bone marrow plasma cells and gelatin-zymography of their CM showed that active MM patients express significantly higher (P 〈 .01) levels of MMP-2 mRNA and protein when compared with nonactive MM and MGUS patients, whereas MMP-9 expression was similar in all groups. Taken together, these findings indicate that the progression of plasma cell tumors is accompanied by an increase of bone marrow neovascularization. This is paralleled by an increased angiogenic and invasive potential of bone marrow plasma cells, which is dependent, at least in part, by FGF-2 and MMP-2 production. Induction of angiogenesis and secretion of MMPs by plasma cells in active disease may play a role in their medullary and extramedullary dissemination, raising the hypothesis that angiostatic/anti-MMP agents may be used for therapy of MM.