Spencer, Andrew

Abstract Abstract 750 Background: DKK1 is a negative regulator of the Wnt signaling pathway in bone that is overexpressed in a subset of newly-diagnosed MM patients with osteolytic lesions as well as in refractory and relapsed patients. Expression also correlates with the number of osteolytic lesions in untreated MM patients. BHQ880 is a novel anti-DKK1 human monoclonal antibody. Alleviation of DKK1 inhibition by BHQ880 results in activation of the Wnt signaling pathway, leading to increased bone mass mediated via upregulation of osteoblasts in mice and monkeys. In murine models of MM bone disease; this anabolic activity of BHQ880 increased trabecular and cortical bone density. Lytic bone disease in MM is caused by osteoclast activation and osteoblast inhibition. Current approved therapies for the treatment of MM bone disease are focused on osteoclast inhibition (e.g., bisphosphonates) and BHQ880 therapy may be able to reverse the effects of DKK1-induced osteoblast inhibition. Therefore, dual therapy with zoledronic acid to decrease bone resorption and BHQ880 to increase new bone formation may provide an effective treatment strategy for MM bone disease. Methods: In the phase I portion of this phase I/II study, patients with relapsed or refractory MM with prior skeletal-related event (SRE) were treated with BHQ880 as an IV infusion Q28 days. Patients also received Zol (4 mg) and approved MM Tx (bortezomib not allowed). Bone markers and total DKK1 levels along with bone mineral density are being measured. Full PK profiles were collected during the first and second cycle, after which predose (trough) samples were collected to assess accumulation. Results: Ten pts (6:M, 4:F), median age: 66.5 yrs (range 41- 70), performance status-0(5 pts), 1(4 pts), 2 (1 pts) have been enrolled in the following dose levels (mg/kg) 3 (2 pts), 10 (starting dose level -4 pts), 20 (4 pts) and have been on treatment for 1 day to 5 28-day cycles. No BHQ880-related AE's have been observed to date. Bone mineral density (BMD) data from the first two patients treated at 10 mg show the following: a.) Pt 1 (hip +5.8%, spine N/A due to surgery, wrist -1.8%); b.) Pt 2 (hip -0.2%, spine +6.1%, wrist not done). The biomarker data from these patients show: a.) Pt 1 shows a maximal +98% change over baseline in PINP at day 15 post-treatment, while osteocalcin (OC) changes +17% at day 15, reaching a +56% change over baseline at cycle 4 day 1; uNTx/Cr changes – 43 % at cycle 2 day 15. b) Partial data from Pt 2 suggests a -44 % change in PINP and –73 % change in OC and a +73% change in uNTx/Cr. Baseline total DKK1 levels on 3 patients ranged from 8.8 to 21.5 ng/mL. Preliminary PK analysis is available in 1 out of 3 patients treated at 10mg/kg. The Cmax achieved after the first infusion was 165 ug/mL and 201 ug/mL after the second infusion. Calculated t1/2 was 188 hours after the first infusion and 254 hours after the second infusion. Regarding overall exposure, AUC0-672 hours after first infusion was 36081 hr*ng/mL and 48533 hr*ng/mL after the second infusion. Conclusion: BHQ880 given IV Q28 days appears to be well tolerated in combination with Zol and chosen MM Tx. Once safety of 40 mg/kg BHQ880 or the MTD dose has been determined, pts will be enrolled in the phase II portion to assess activity on a SRE endpoint. Updated safety, efficacy, bone density and biomarker data will be presented on all patients at the upcoming ASH meeting. Disclosures: Padmanabhan: Genentech: Consultancy, Honoraria; GSK: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau. Off Label Use: BHQ880, a novel osteoblast activating, anti-DKK1 antibody. Dzik-Jurasz:Novartis: Employment, Equity Ownership. Gangolli:Novartis: Employment, Equity Ownership. Ettenberg:Novartis: Employment, Equity Ownership. Miner:Novartis: Employment, Equity Ownership. Bilic:Novartis: Employment, Equity Ownership. Whyte:Novartis: Employment, Equity Ownership. Mehdi:Novartis: Employment, Equity Ownership. Chiang:Novartis: Employment, Equity Ownership. Rae:Novartis: Employment, Equity Ownership. Shah:Novartis: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Millenium: Research Funding, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Elan: Consultancy. Giles:Novartis: Consultancy, Research Funding; BMS: Research Funding; Merck: Research Funding; Clavis: Research Funding. Stewart:Novartis: Consultancy; Amgen: Consultancy; Millenium: Consultancy, Research Funding; Proteolix: Consultancy; Celgene: Honoraria.

Abstract Abstract 4055 Introduction: Approximately 15% of patients (pts) with multiple myeloma (MM) exhibit a t(4;14) translocation that results in constitutive activation of the receptor tyrosine kinase (RTK) fibroblast growth factor receptor 3 (FGFR3) in the absence of ligand. This translocation has been strongly linked with a poor prognosis and short survival compared with pts without this translocation. Dovitinib (TKI258) is an RTK inhibitor that has demonstrated in vitro inhibitory activity against FGFR (including FGFR3), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR), with IC50values of approximately 10 nM. Tumor growth inhibition was observed in xenograft tumor models of MM treated with dovitinib. This study was designed to evaluate the efficacy and safety of dovitinib in pts with relapsed or refractory MM that is either t(4;14) positive or negative. Patients and Methods: Adult pts who had received at least 2 prior antimyeloma regimens and who had relapsed or were refractory to their last treatment regimen were enrolled in this multicenter, open-label, 2-stage, phase 2 trial. Pts were evaluated for t(4;14) status at the baseline visit and classified according to the result into either a t(4;14)-positive or a t(4;14)-negative group. Dovitinib was administered at a dose of 500 mg/day on a 5-days-on/2-days-off schedule. Response was characterized as per the International Myeloma Working Group (IMWG) criteria. The primary endpoint was extended overall response rate as defined by the rate of pts with best overall response of complete response, very good partial response, partial response, or minor response. Secondary endpoints included safety, overall response rate, progression-free survival, and pharmacokinetics. After disease progression, pts had the option to continue treatment with the addition of low-dose dexamethasone (40 mg every 7 days) with M-protein levels at the time of progression considered as the new baseline. Results: A total of 43 pts were enrolled in this study; 26 pts were t(4;14) negative, 13 were t(4;14) positive, and 4 pts had unknown/indeterminate t(4;14) status. Median age was 63 years. Most pts (86%; n = 37) had received ≥ 3 prior lines of therapy. No objective responses were observed in either group of pts. Due to the apparent lack of efficacy, the study did not proceed to stage 2. The following observations are based on the preliminary data. In the t(4;14)-negative group, median duration of exposure to the study drug was 4.0 weeks, and 9 of the 26 pts (35%) had stable disease, 13 (50.0%) had progressive disease, and 4 (15%) were not evaluable. Due to slow enrollment and lack of efficacy among the earlier enrolled t(4;14)-positive pts, enrollment for the t(4;14)-positive group was closed prematurely. Among the 13 enrolled t(4;14)-positive pts, median duration of exposure to the study drug was 8.7 weeks. Best responses were stable disease for 8 pts (62%), disease progression for 3 pts (23%), and unknown for 2 pts (15%). Among both groups, the most common adverse events of any grade, regardless of study drug, were nausea (67%), diarrhea (58%), vomiting (51%), fatigue (47%), thrombocytopenia (33%), and anemia (28%). Most of the nonhematologic events were mild. The most common grade 3/4 adverse events were thrombocytopenia (26%) and anemia (23%). The principal reasons for discontinuation of dovitinib monotherapy were disease progression (72%) and adverse events (19%). Six pts continued on the dovitinib plus dexamethasone regimen; 1 pt is ongoing, and 5 pts discontinued due to disease progression (n = 4) and adverse events (n = 1). Conclusion: Dovitinib was found to have no or minimal single-agent activity in relapsed/refractory myeloma irrespective of t(4;14) status. Although the patient numbers are small, the rate of patients with stable disease during study treatment who may have had a clinical benefit was higher in the t(4;14)-positive group, suggesting that this subgroup may be a candidate to explore combination treatment of dovitinib with other agents, such as proteasome inhibitors. Gastrointestinal toxicity, while mostly mild, remains a challenge, and timely monitoring and supportive care during dovitinib treatment may alleviate these symptoms. Dovitinib may be a promising agent for combination therapies to improve prognosis of patients with t(4;14)-positive MM. Disclosures: Scheid: Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Reece:Millennium Pharmaceuticals: Research Funding; Otsuka: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Spencer:Celgene: Honoraria; Janssen: Honoraria, Speakers Bureau; Novartis: Honoraria. Callander:Millennium Pharmaceuticals: Research Funding. Sonneveld:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Honoraria, Research Funding. Kalimi:Novartis Pharmaceuticals: Employment. Cai:Novartis: Employment. Shi:Novartis: Employment, Equity Ownership. Scott:Novartis: Employment. Stewart:Millennium Pharmaceuticals: Consultancy, Honoraria, Research Funding; Onyx: Consultancy; Celgene: Consultancy.

Background:Patients (pts) with multiple myeloma associated with high cytogenetic risk abnormalities have poor outcomes. In CASTOR, D‐Vd prolonged progression‐free survival (PFS) vs bortezomib and dexamethasone (Vd) alone, and exhibited a manageable safety profile in pts with RRMM. We conducted a subgroup analysis of D‐Vd vs Vd in CASTOR, based on cytogenetic risk.Aims:The purpose of this analysis was to determine the efficacy and safety of D‐Vd in CASTOR based on cytogenetic risk status.Methods:Eligible pts received ≥1 prior line of therapy. Cytogenetic risk was based on a combined analysis of next‐generation sequencing (NGS) and fluorescence in situ hybridization (FISH)/karyotype testing. High‐risk pts had t(4;14), t(14;16), or del17p abnormalities. Standard (std)‐risk pts were confirmed negative for all 3 abnormalities. Minimal residual disease (MRD; 10–5) was assessed via NGS using clonoSEQ® assay V2.0.Results:In CASTOR (D‐Vd, n = 251; Vd, n = 247), high‐risk was confirmed in 26.7% and 25.9% of pts in the D‐Vd and Vd groups, respectively. At a median follow up of 40.0 months (mo), D‐Vd prolonged PFS vs Vd in pts with high‐ (median 13.4 vs 7.2 mo; HR, 0.40 [95% CI, 0.24–0.65]; P = 0.0002) or std‐risk (median 18.4 vs 6.8 mo; HR, 0.28 [95% CI, 0.20–0.37]; P <0.0001). Higher ORR was seen with D‐Vd vs Vd (high risk: 84.8% vs 60.0%; P = 0.0226; std risk: 85.4% vs 65.0%; P <0.0001), including deep responses of ≥CR (high risk: 33.3% vs 8.3%; std risk: 29.9% vs 10.2%) and ≥VGPR (high risk: 65.2% vs 35.0%; P = 0.0049; std risk: 64.3% vs 28.0%; P <0.0001). Higher rates of MRD negativity (high risk: 17.9% vs 0%; P = 0.0003; std risk: 13.3% vs 2.4%; P = 0.0003), and sustained MRD negativity for ≥6 mo (high risk: 16.4% vs 0%; P = 0.0006; std risk: 6.1% vs 1.8%; P = 0.0859) and ≥12 mo (high risk: 7.5% vs 0%; P = 0.0581; std risk: 1.8% vs 0%; P = 0.2477) were seen with D‐Vd vs Vd. D‐Vd significantly prolonged PFS vs Vd in pts with one prior line of therapy only (high risk: median 20.1 vs 8.4 mo; HR, 0.30 [95% CI, 0.14–0.64]; P = 0.0012; std risk: median 32.6 vs 7.9 mo; HR, 0.18 [95% CI, 0.11–0.29]; P <0.0001; Figure). Additionally, D‐Vd significantly prolonged PFS2 (high risk: median 27.9 vs 18.6 mo; HR, 0.59 [95% CI, 0.37–0.94]; P = 0.0258; std risk: median 40.1 vs 21.6 mo; HR, 0.43 [95% CI, 0.32–0.59]; P <0.0001) regardless of cytogenetic risk status.Additional data including safety analyses will be presented.Summary/Conclusion:Adding daratumumab to Vd demonstrates significant efficacy in pts with high‐risk RRMM including PFS2. Among high‐risk RRMM pts, MRD negativity was only achieved with D‐Vd. These findings support use of D‐Vd for high‐risk RRMM. NCT02136134image

SummaryThere is a need for efficacious, convenient treatments with long‐term tolerability for patients with relapsed/refractory multiple myeloma (RRMM). This phase 2 study evaluated the all‐oral combination of ixazomib, cyclophosphamide and dexamethasone (ICd). Patients with RRMM received ixazomib 4 mg and cyclophosphamide 300 mg/m2 on days 1, 8 and 15, and dexamethasone 40 mg on days 1, 8, 15 and 22 in 28‐day cycles. The primary endpoint was overall response rate (ORR). Seventy‐eight patients were enrolled (median age 63·5 years). At data cut‐off, patients had received a median of 12 treatment cycles; 31% remained on treatment. ORR was 48% [16% very good partial response or better (≥VGPR)]. ORR was 64% and 32% in patients aged ≥65 and <65 years (25% and 16% ≥VGPR), respectively. At a median follow‐up of 15·2 months, median progression‐free survival (PFS) was 14·2 months, with a trend towards better PFS in patients aged ≥65 years vs. <65 years (median 18·7 months vs. 12·0 months; hazard ratio 0·62, P = 0·14). ICd was well tolerated. The most common treatment‐emergent adverse events were diarrhoea (33%), nausea (24%), upper respiratory tract infection (24%), and thrombocytopenia (22%); 10 patients (13%) had peripheral neuropathy (one grade 3). This study is registered at ClinicalTrials.gov (NCT02046070).

LBA4 Background: Daratumumab (D), a human anti-CD38 IgGκ mAb, induces deep and durable responses with a favorable safety profile in RRMM pts. We report a pre-specified interim analysis of the first randomized controlled study of D (CASTOR; NCT02136134). Methods: Pts with ≥1 prior line of therapy were randomized (1:1) to 8 cycles (q3w) of bortezomib (V)/dexamethasone (d) (V: 1.3 mg/m2sc on Days 1, 4, 8, 11; d: 20 mg po on Days 1, 2, 4, 5, 8, 9, 11, 12) ± D (16 mg/kg iv qw in Cycles 1-3, Day 1 of Cycles 4-8, then q4w until progression). Primary endpoint was PFS. Results: 498 pts (DVd, 251; Vd, 247) were randomized. Baseline demographics and disease characteristics were well balanced. Pts received a median of 2 prior lines of therapy (range 1-10). 66% received prior V; 76% received prior IMiD; 48% received prior PI and IMiD; 33% were IMiD-refractory; 32% were refractory to last line of prior therapy. With median follow-up of 7.4 months, D significantly improved median PFS (61% reduction in risk of progression) and TTP for DVd vs Vd (Table). D significantly increased ORR (83% vs 63%, P <0.0001), and doubled rates of ≥VGPR (59% vs 29%, P <0.0001), and ≥CR (19% vs 9%, P= 0.0012) for DVd vs Vd, respectively; median duration of response was NR vs 7.9 months, respectively. Most common (>25%) AEs (DVd/Vd) were thrombocytopenia (59%/44%), peripheral sensory neuropathy (47%/ 38%), diarrhea (32%/22%) and anemia (26%/31%). Most common grade 3/4 AEs (>10%) were thrombocytopenia (45%/33%), anemia (14%/16%), neutropenia (13%/4%). 7%/9% of pts discontinued due to a TEAE. D-associated infusion-related reactions (45% of pts) mostly occurred during the first infusion; most were grade 1/2 (grade 3/4, 9%/0%). Conclusions: D significantly improved PFS, TTP, and ORR in combination with Vd vs Vd alone. DVd doubled both VGPR and sCR/CR rates vs Vd alone. Safety of DVd is consistent with the known safety profile of D and Vd. The addition of D to Vd should be considered a new standard of care for RRMM pts currently receiving Vd alone. Clinical trial information: NCT02136134. [Table: see text]

SummaryThe oral proteasome inhibitor ixazomib is approved in the United States, European Union and other countries, in combination with oral lenalidomide and dexamethasone (Rd), for the treatment of patients with multiple myeloma who have received at least one prior therapy. Approval was based on the global, randomised, double‐blind, placebo‐controlled Phase III TOURMALINE‐MM1 study of ixazomib‐Rd (IRd) versus placebo‐Rd in patients with relapsed/refractory multiple myeloma. IRd resulted in a significant improvement in progression‐free survival versus placebo‐Rd (median: 20·6 vs. 14·7 months; hazard ratio 0·74). Common toxicities observed more commonly with IRd versus placebo‐Rd were thrombocytopenia, nausea, vomiting, diarrhoea, constipation, rash, peripheral neuropathy, peripheral oedema and back pain; these were generally grade 1/2 in severity except for thrombocytopenia (19% vs. 9% grade 3/4), which appeared manageable and reversible, with no differences between arms in significant bleeding or dose discontinuations. No cumulative toxicities were observed, indicating the potential feasibility of long‐term IRd treatment. Safety data from TOURMALINE‐MM1 are reviewed and guidance for managing clinically relevant adverse events associated with IRd is provided. Most toxicities were manageable with supportive care and dose delays or reductions as needed. Clinicians should be aware of and understand these potential side effects to optimise and prolong patient benefit.

BACKGROUNDNVP‐AUY922 (AUY; Luminespib) with or without bortezomib showed preclinical activity against multiple myeloma (MM) cells. This phase 1/1B study assessed NVP‐AUY922 alone and with bortezomib in patients with relapsed or refractory MM.METHODSDose escalation was guided by an adaptive Bayesian logistic regression model. In phase 1, patients who progressed after 2 to 4 prior therapies received NVP‐AUY922 intravenously once weekly. In phase 1B, patients who progressed after 2 or fewer prior therapies received NVP‐AUY922 plus bortezomib. The primary objective was to determine the maximum tolerated dose (MTD) of NVP‐AUY922.RESULTSTwenty‐four patients received NVP‐AUY922 monotherapy at doses of 8 to 70 mg/m2. One dose‐limiting toxicity (DLT) was observed (grade 3 blurred vision at 70 mg/m2); no MTD was reached. The recommended phase 2 dose was 70 mg/m2. The most frequent drug‐related adverse events (AEs) were diarrhea, nausea, and ocular toxicities. Grade 3/4 AEs were uncommon (<10%). Eight patients discontinued treatment because of AEs; 5 had ocular toxicities (≥45 mg/m2). The best response was stable disease in 66.7% of the patients. There were no partial or complete responses. Five patients received NVP‐AUY922 (which was started at 50 mg/m2) plus bortezomib (1.3 mg/m2). Three of these patients experienced DLT. No further dose escalation was performed; the MTD for NVP‐AUY922 plus bortezomib was not established.CONCLUSIONSThis study showed disease stabilization with NVP‐AUY922 in patients with relapsed or refractory MM. The MTD for NVP‐AUY922 was not reached, but reversible ocular toxicity has been reported at high dose levels. Bortezomib at the standard recommended dose plus NVP‐AUY922 was not tolerated. Cancer 2015;121:2185–2192. © 2015 American Cancer Society.