Maciag, Paulo

AbstractVenetoclax (Ven) is a selective small‐molecule inhibitor of BCL‐2 that exhibits antitumoral activity against MM cells with t(11;14) translocation. We evaluated the safety and efficacy of Ven and dexamethasone (VenDex) combination in patients with t(11;14) positive relapsed/refractory (R/R) multiple myeloma (MM). This open‐label, multicenter study had two distinct phases (phase one [P1], phase two [P2]). Patients in both phases received VenDex (oral Ven 800 mg/day + oral Dex 40 mg [20 mg for patients ≥75 years] on days 1, 8, and 15, per 21–day cycle). The primary objective of the P1 VenDex cohort was to assess safety and pharmacokinetics. Phase two further evaluated efficacy with objective response rate (ORR) and very good partial response or better. Correlative studies explored baseline BCL2 (BCL‐2) and BCL2L1 (BCL‐XL) gene expression, cytogenetics, and recurrent somatic mutations in MM. Twenty and 31 patients in P1 and P2 with t(11;14) positive translocation received VenDex. P1/P2 patients had received a median of 3/5 lines of prior therapy, and 20%/87% were refractory to daratumumab. Predominant grade 3/4 hematological adverse events (AEs) with ≥10% occurrence included lymphopenia (20%/19%), neutropenia (15%/7%), thrombocytopenia (10%/10%), and anemia (5%/16%). At a median follow‐up of 12.3/9.2 months, ORR was 60%/48%. The duration of response estimate at 12 months was 50%/61%, and the median time to progression was 12.4/10.8 months. In biomarker evaluable patients, response to VenDex was independent of concurrent del(17p) or gain(1q) and mutations in key oncogenic signaling pathways, including MAPK and NF‐kB. VenDex demonstrated efficacy and manageable safety in heavily‐pre‐treated patients with t(11;14) R/R MM.

TPS8554 Background: BCL-2 is an anti-apoptotic protein important for myeloma cell survival. Venetoclax (Ven) is a highly selective, potent, oral BCL-2 inhibitor, that has shown promise in clinical studies as monotherapy or in combination with other agents in patients with t(11;14)-positive relapsed/refractory multiple myeloma (RRMM; Kumar et al. Blood. 2017; Costa et al. ASH 2018. Abstr. #303; Harrison et al. ASH 2019. Abstr. #142; Bahlis et al. ASH 2019. Abstr. #925; Kaufman et al. ASH 2019. Abstr. #926). Notably, t(11;14)-positive MM is more dependent on BCL-2 for cell survival, which, together with these clinical data, suggests that Ven combined with dexamethasone (Dex) may provide greater clinical benefit versus standard therapies, like pomalidomide (Pom), in this biomarker-defined patient population. This ongoing Phase 3 study (CANOVA; NCT03539744) aims to evaluate the safety and efficacy of VenDex vs PomDex in t(11;14)-positive RRMM. Methods: Eligible patients (≥18 years) must have t(11;14)-positive RRMM per central lab, an ECOG performance status ≤2, received ≥2 prior lines of therapy, previously received a proteasome inhibitor, and must be refractory to lenalidomide and last line of therapy. Patients cannot have history of treatment with Ven, Pom, or other BCL-2 inhibitors. Patients will be randomized 1:1 to Ven (800 mg orally, once-daily) or Pom (4 mg orally, once-daily on days 1-21 of 28-day cycles). Patients in both groups will receive 40 mg Dex (20 mg for patients ≥75 years) once weekly. Treatment will continue until disease progression, unacceptable toxicity, or withdrawal from study. Patients will be stratified based on age at randomization ( < 65 vs ≥65 years), prior lines of therapy (2 to 3 vs ≥4), and International Staging System stage at screening (I vs II vs III). The primary endpoint is progression-free survival (PFS) per independent review committee (IRC) assessment based on International Myeloma Working Group criteria. The final PFS analysis will be performed when approximately 147 PFS events per IRC are observed. Secondary endpoints are response rate, patient-reported outcomes, overall survival, duration of response, times to response and progression, minimal residual disease negativity rate, safety, and Ven pharmacokinetics. Approximately 244 patients will be enrolled; as of January 21, 2020, 28 patients have been randomized (from 19 sites in 12 countries) and enrollment is ongoing. Clinical trial information: NCT03539744 .

8547 Background: Venetoclax (Ven) is a selective, potent BCL-2 inhibitor that has synergistic activity with bortezomib (B) and dexamethasone (d). In the Phase 3 BELLINI trial, addition of Ven to Bd significantly improved median progression-free survival (PFS) and response rates, including minimal residual disease (MRD) negativity, but resulted in increased mortality vs placebo (Pbo). Here, we determine whether MRD negativity was associated with longer PFS and OS in relapsed/refractory multiple myeloma (RRMM) patients treated with Ven+Bd in the BELLINI dataset. Methods: In BELLINI (NCT02755597), RRMM patients (pts) sensitive or naïve to proteasome inhibitors with 1-3 prior lines of therapy were randomized 2:1 to Ven (800 mg) or Pbo plus B (1.3 mg/m2) and d (20 mg). Next-gen sequencing MRD assessments were done on bone marrow aspirates at the time of suspected CR/sCR, and 6- and 12-months post confirmation of CR/sCR. Patients with a missing or indeterminate assessment were considered MRD positive. Evaluation of MRD in biomarker-defined subgroups (cytogenetics and BCL2 expression) was also performed and will be presented. Results: In total, 291 pts were randomized; 194 to Ven, 97 to Pbo. As of 13 Sep 2019, the median follow-up was 29 months. Ven + Bd demonstrated significantly higher MRD negativity rates ( < 10−5), including a higher proportion of pts achieving sustained MRD negativity (Table). In the Ven arm, the median (m)PFS was not reached for MRD negative pts vs 16.2 months for MRD positive pts (HR = 0.23, 95% CI: 0.10-0.54, p < 0.001). While the mOS was not reached in the Ven arm, OS was significantly longer for MRD negative vs MRD positive pts (HR = 0.25, 95% CI: 0.08-0.80, p = 0.0194). Conclusions: The addition of Ven to Bd resulted in deep and durable responses, including higher rates of MRD negativity. MRD negativity in the context of Ven was associated with prolonged survival in patients with RRMM, consistent with the broader MRD body of evidence with other therapies in MM. Clinical trial information: NCT02755597 . [Table: see text]

8509 Background: Venetoclax (Ven) is a selective, potent, oral BCL-2 inhibitor. In the Phase 3 BELLINI trial, addition of Ven to bortezomib (B) + dexamethasone (d) significantly improved response rates and progression-free survival (PFS) vs placebo (Pbo) and showed significant efficacy in patients (pts) with either t(11;14) or BCL2high gene expression. Here we present updated safety and efficacy data from the prespecified second interim overall survival (OS) analysis. Methods: In this multicenter, randomized, double-blind study (NCT02755597), pts with relapsed/refractory multiple myeloma (RRMM) with 1-3 prior lines of therapy were randomized 2:1 to Ven (800 mg) or Pbo in combination with B (1.3 mg/m2) and d (20 mg). The primary endpoint was PFS; key secondary endpoints included overall response and overall survival (OS). Results: 291 pts were randomized; 194 to Ven, 97 to Pbo. Pt characteristics were well balanced among arms. In the Ven arm, median age was 66, 17% had high-risk cytogenetics, 11% had t(11;14), and 34% had BCL2high gene expression. As of 13 Sept 2019, 59 pts were still on study, 45 (23%) Ven vs 14 (14%) Pbo. At a median follow-up of 28.6 months, there were 64 (33%) deaths in the Ven arm vs 24 (25%) in Pbo. At the initial data cutoff (26 Nov 2018), PFS HR was 0.63 (0.44,0.90) and OS HR was 2.03 (1.04,3.95). Table shows updated PFS and OS. Most common treatment-emergent adverse events (TEAEs) with Ven were diarrhea (59%), nausea (37%), and constipation (35%). Most common grade 3/4 AEs (Ven/Pbo) were neutropenia (21%/8%), thrombocytopenia (15%/30%), anemia (16%/15%), diarrhea (15%/12%), and pneumonia (18%/13%). Serious AEs occurred in 54% Ven and 52% Pbo pts. 24% discontinued Ven due to AEs vs 12% Pbo. There were 14 treatment-emergent deaths in the Ven arm and 1 in Pbo. Conclusions: The addition of Ven to Bd significantly improves PFS but resulted in increased mortality vs Pbo in the total population. Greatest PFS improvement with Ven was observed in pts with t(11;14) or BCL2high gene expression, where Ven shows a favorable benefit-risk profile. The study continues for final OS analysis. Clinical trial information: NCT02755597 . [Table: see text]

Background Venetoclax (Ven) is a selective, small molecule inhibitor of anti-apoptosis protein Bcl-2 that has antitumoral activity against multiple myeloma (MM), notably those with translocation t(11;14). Dexamethasone (d) has shown to enhance the expression of BCL-2 and pro-apoptotic protein Bim, shifting its binding towards Bcl-2 and sensitizing MM cells to Ven. This Phase 1/2 open-label trial is evaluating the safety and efficacy of the combination of Ven+d as a therapeutic approach to improve clinical outcomes in patients with t(11;14) Relapsed/Refractory (R/R) MM. Methods This ongoing study (NCT01794520) has 2 distinct phases. Phase 1 (P1) consisted of separate dose escalation, safety expansion, and Ven+d combination cohorts. The phase 2 (P2) portion is an expansion cohort of Ven+d to further evaluate its efficacy. The safety and efficacy of the Ven+d cohorts from P1 and P2 are reported here. Eligible patients (pts) were adults with t(11;14) R/R MM ≥18 years of age. Key eligibility criteria for the Ven+d cohort in P1 included prior treatment with a proteasome inhibitor (PI) and an immunomodulatory drug (IMID), and an ECOG score ≤1. In P2, eligibility included an ECOG score ≤2, disease progression on or within 60 days from the last dose on previous treatment and having received at least two lines of therapy with a PI, IMID, daratumumab, and glucocorticoids. Additional inclusion criteria for both phases included measurable disease and adequate bone marrow function in all pts, and the presence of t(11;14) determined by fluorescence in-situ hybridization. In both phases, pts received oral Ven 800 mg/day + oral d 40 mg (20 mg for pts ≥75 years of age) on days 1, 8, and 15 of each 21-day cycle. In P1, preliminary efficacy was assessed as the overall response rate (ORR), time to progression (TTP), progression free survival (PFS), and duration of response (DOR) of Ven+d based on the 2011 International Uniform Response Criteria for MM. Efficacy in P2 further evaluated ORR, very good partial response (VGPR) or better, PFS, DOR, TTP, and overall survival (OS) using 2016 IMWG response criteria. Results In P1, as of 15thApril, 2019, 20 pts were enrolled (17 [85%] male; median age, 63 years [range, 46-77]). The median number of prior therapies received was 2.5 (range: 1-7). Nineteen pts (95%) discontinued the study (18 due to progressive disease and 1 underwent transplant). The treatment-emergent adverse events (TEAEs) are summarized in the Table. Most frequent TEAEs were insomnia (45%), hypophosphatemia (40%), hyperglycemia (35%), diarrhea (35%), and thrombocytopenia (30%). Predominant Grade 3 or 4 TEAEs included neutropenia (21%), lymphopenia (29%), and hypophosphatemia (20%). The most common serious TEAE was tumor lysis syndrome (TLS) (10%). No deaths were reported in the treatment-emergent period. ORR was achieved by 13 (65%) and ≥VGPR was achieved by 6 (30%) pts respectively. Partial response (PR) was observed in 7 (35%) pts and stable disease (SD) in 4 (20%) pts. Median time to first response was 1.4 mos (95% CI: 0.7, 2.8). The DOR was 13.1 mos (95% CI: 10.9, 21.9). Median PFS and TTP were both 12.4 mos (95% CI 3.6, 20.9). In P2, as of March 18, 2019, 31 pts were enrolled (18 [58%] male; median age, 65 years [range, 48-80]). The median number of prior therapies received were 5 (range: 1-9). Eight (26%) pts discontinued the study (6 deaths, 1 withdrew consent, 1 due to physician's decision). The most frequent TEAEs reported were diarrhea (32%), nausea (26%) and lymphopenia (32%). The most frequent Grade 3 or 4 TEAEs were lymphopenia (32%), thrombocytopenia (11%), and hypertension (10%). Most common serious TEAE was sepsis (10%). Six (19%) deaths were reported (5 due to progressive disease and 1 due to adverse event). In the intention to treat population, the median TTR was 0.7 mos (range: 0.6-1.5). ORR was achieved by 14 (45%) and &gt;VGPR was observed in 8 (26%) pts. PR was observed in 6 (13%) pts and SD in 8 (26%) pts. Median PFS, DOR, and OS were not reached at the time of data analysis. The 9-mo estimates for PFS, DOR, and OS were 57% (95% CI: 19% 82%), 66% (95% CI: 16%, 91%), and 71% (95% CI: 44%, 87%) respectively. Conclusion In both phases of this study, Ven+d was efficacious and demonstrated tolerable safety in pts with t(11;14) R/R MM. These results support further investigation of Ven combinations in this pt population. This combination is also being investigated in the ongoing Phase 3 trial M13-494 (CANOVA) in t(11;14) positive R/R MM. Disclosures Kaufman: Takeda: Consultancy; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Bristol-Myers Squibb: Consultancy; Incyte: Consultancy; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; AbbVie: Consultancy; Winship Cancer Institute of Emory University: Employment; Amgen: Consultancy; TG Therapeutics: Consultancy. Gasparetto:Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Schjesvold:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; MSD: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; SkyliteDX: Honoraria. Moreau:Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Facon:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees. Boise:Genentech Inc.: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria, Research Funding. Alzate:AbbVie Inc: Employment, Other: Stock/stock options. Macartney:AbbVie Inc: Employment, Other: Stock/stock options. Pesko:AbbVie: Employment, Other: Stock/stock options. Salem:AbbVie: Employment, Other: Stock/stock options. Ross:AbbVie: Employment, Other: Stock/stock options. Hong:Genentech Inc.: Employment, Equity Ownership; Roche: Equity Ownership. Maciag:AbbVie: Employment, Other: Stock/stock options. Pauff:AbbVie Inc: Employment, Other: may own stock or stock options. Kumar:Takeda: Research Funding; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding. OffLabel Disclosure: Venetoclax is a BCL-2 inhibitor that is FDA-approved in some indications. This presentation will focus on venetoclax for treatment in multiple myeloma, which is not an approved indication.

Background: Overexpression of the anti-apoptotic BCL-2 protein promotes multiple myeloma (MM) cell survival. Venetoclax (Ven) is a highly selective, potent, oral BCL-2 inhibitor that induces apoptosis and has shown synergistic activity with bortezomib (B) and dexamethasone (d). Phase 1 studies in relapsed/refractory (RR) MM demonstrated encouraging clinical efficacy of Ven + d in t(11;14) MM and in a broader patient (pt) population in combination with Bd. Recent results from the Phase 3 BELLINI study of Ven vs placebo (Pbo) + Bd in pts with RRMM demonstrated that pts treated with Ven + Bd had improved clinical response rates and progression-free survival (PFS) vs Pbo, although the overall survival (OS) result was in favor of Pbo. Subgroup analyses showed different efficacy and survival outcomes based on tumor cytogenetics and BCL-2 expression. Results of pre-specified subgroup analyses and additional retrospective correlative biomarker analyses in the Phase 3 BELLINI study are described herein. Methods: BELLINI (NCT02755597) was a randomized, double-blind, multicenter Phase 3 study of Ven or Pbo + Bd in pts with RRMM who received 1-3 prior therapies and were either sensitive or naïve to PIs. Pts were randomized 2:1 to receive Ven 800 mg/day or Pbo + Bd. The following biomarker analyses were performed by central laboratory assessments of pre-treatment tumor samples: BCL-2 protein expression by immunohistochemistry (IHC) analysis of bone marrow (BM) core biopsies; BCL2 gene expression by quantitative PCR (qPCR) and cytogenetic abnormalities by interphase fluorescence in situ hybridization (FISH) analysis of CD138-enriched BM mononuclear cells. Correlation between BCL-2 (protein and gene) expression, cytogenetics, and outcomes were examined by Kruskal-Wallis tests and by hazard ratio (HR) using the Cox proportional hazard model. Results: As of the data cut-off of 18 Mar 2019, 291 pts were randomized, 194 to the Ven arm and 97 to the Pbo arm. Out of the 291 pts randomized, 177 pts (61%) were evaluable by IHC, 257 pts (88%) by qPCR, and 262 pts (90%) by FISH. A broad range of BCL2 gene expression was observed (median 2-DCt: 0.212 [range: 0-5.21]), which strongly correlated with protein expression (median 2-DCt 0.115 in BCL-2 IHC Low vs 0.277 in BCL-2 IHC High, p=0.0021). t(11;14) MM had the highest levels of BCL-2 expression (23/23 BCL-2 High by IHC; median 2-DCt 0.406 vs 0.212 in t(11;14) negative, p=0.0132), however high BCL-2 expression was not limited to the t(11;14) subgroup. Univariate analyses showed higher BCL2 expression in pt tumor samples with del(13q) (median 2-DCt 0.333 vs 0.159 in pts without del(13q), p=0.0008) and gain(1q) (median 2-DCt 0. 295 vs 0.180 in pts without gain(1q), p=0.0059). Bootstrapping and aggregating thresholds from trees (BATTing) was used retrospectively to identify an estimated threshold value for BCL2 expression (2-DCt ≥0.323) that could provide optimum selection of pts with maximum improvement in PFS when treated with Ven+Bd. Biomarker subgroups with the greatest PFS improvement were t(11;14) (HR=0.10; 95% CI: 0.02-0.46, p=0.003) and High BCL2 by qPCR (HR=0.26; 95% CI: 0.13-0.51, p&lt;0.001; Table 1). Since the t(11;14) and High BCL2 patient populations do not completely overlap (20% of High BCL2 pts were t(11;14) and 54% of t(11;14) were High BCL2), a combined subgroup analysis was performed. For pts with t(11;14) or High BCL2, the median PFS was not reached in the Ven arm vs 9.9 mo in Pbo (HR=0.26, 95% CI: 0.14-0.48, p&lt;0.001; Table 1). Higher overall response (ORR, 88% vs 70%), very good partial response or better (≥VGPR, 73% vs 33%), and complete response or better (≥CR, 42% vs 3%) rates were observed in the Ven vs Pbo arm (Table 2). Minimal residual disease negativity (MRD-, 10-5) rate was also higher for t(11;14) or High BCL2 pts in the Ven vs Pbo arm (19% vs 0%). Median overall survival (OS) was not reached in either arm but was similar between treatment arms for the combined group with t(11;14) or High BCL2 pts (HR=0.92, 95% CI=0.39-2.16, p=0.85). In contrast, in the t(11;14) negative and Low BCL2 pts, OS favored Pbo (HR=3.13, 95% CI=1.2-8.13, p=0.019; Table 1). Conclusions: Adding Ven to Bd demonstrates significant efficacy in pts with RRMM harboring either t(11;14) or tumor cells expressing high levels of BCL2. The benefit-risk profile appears to be favorable in these subsets of pts and additional studies to gain further safety and efficacy information are warranted. Disclosures Harrison: GSK: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: investigator on studies, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Cavo:celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; novartis: Honoraria; takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; bms: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. De La Rubia:AMGEN: Consultancy; Takeda: Consultancy; AbbVie: Consultancy; Janssen: Consultancy; Celgene Corporation: Consultancy. Popat:Celgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses; Janssen: Honoraria, Other: travel support to meetings; GSK: Consultancy, Honoraria; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Other: travel, accommodations, expenses. Gasparetto:Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Hungria:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Salwender:Amgen: Honoraria, Other: Travel or accommodations; Bristol-Myers Squibb: Honoraria, Other: Travel or accommodations; Janssen Cilag: Honoraria, Other: Travel or accommodations; Sanofi: Honoraria, Other: Travel or accommodations; Celgene: Honoraria, Other: Travel or accommodations; AbbVie: Honoraria; Takeda: Honoraria, Other: Travel or accommodations. Suzuki:Ono: Research Funding; BMS: Honoraria, Research Funding; Takeda: Honoraria; Janssen: Honoraria; Celgene: Honoraria. Moreau:Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria. Spencer:AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Secura Bio: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Specialised Therapeutics Australia: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Haemalogix: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen Oncology: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. O'Dwyer:Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy; GlycoMimetics Inc: Research Funding; BMS: Research Funding; Onkimmune: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding. Garg:Janssen: Honoraria; Novartis, Janssen: Research Funding; Janssen, Takeda, Novartis: Other: Travel expenses. Punnoose:Roche: Other: Stock/stock options; Genentech, Inc.: Employment. Jalaluddin:AbbVie: Employment, Other: Stock/stock options. Jia:AbbVie: Employment, Other: Stock/stock options. Yang:AbbVie: Employment, Other: Stock/stock options. Sun:AbbVie: Employment, Other: Stock/stock options. Ward:AbbVie: Employment, Other: Stock/stock options. Maciag:AbbVie: Employment, Other: Stock/stock options. Ross:AbbVie: Employment, Other: Stock/stock options. Kumar:Takeda: Research Funding; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding. OffLabel Disclosure: Venetoclax is a BCL-2 inhibitor that is FDA-approved in some indications. This presentation will focus on venetoclax for treatment of multiple myeloma, which is not an approved indication.

Background: Venetoclax (Ven) is a highly selective, potent, oral BCL-2 inhibitor that induces apoptosis in multiple myeloma (MM) cells and has shown synergistic activity with the proteasome inhibitor (PI) bortezomib (B) and dexamethasone (d). Ven ± d had encouraging clinical efficacy in both t(11;14) MM and in pts irrespective of genetic background when administered with B, with a tolerable safety profile in Phase 1 studies. Here, we provide updated efficacy and safety of Ven vs placebo (Pbo) + Bd in pts with relapsed/refractory (RR) MM, including subgroup analyses, in the BELLINI study. Methods: BELLINI (NCT02755597) was a Phase 3, randomized, double-blind, multicenter study of Ven or Pbo + Bd in pts with RRMM who received 1 - 3 prior therapies and were either sensitive or naïve to PIs. Pts were randomized 2:1 to receive Ven 800 mg/day or Pbo + Bd. Cycles 1-8 were 21-day with B 1.3 mg/m2 on Days 1, 4, 8, 11 + d 20 mg on Days 1, 2, 4, 5, 8, 9, 11, 12. Cycles 9+ were 35-day with B 1.3 mg/m2 on Days 1, 8, 15, 22 + d 20 mg Day 1, 2, 8, 9, 15, 16, 22, 23. The primary endpoint was progression-free survival (PFS) by independent review committee (IRC). Results: A total of 291 pts were randomized, 194 to the Ven arm and 97 to the Pbo arm. Median age was 66 (range, 36 - 87); 53% had ISS II/III disease; 54% received 2 or 3 prior lines of therapy; 59% had prior stem cell transplant; 70% had prior PI, 68% had prior immunomodulatory drug, 41% had both. Among pts with evaluable results, 18% had high-risk cytogenetics, 13% had MM positive for t(11;14), and 79% had high levels of BCL-2 protein by immunohistochemistry (IHC). In the primary endpoint analysis per IRC, the median PFS was 22.4 months (m) in Ven vs 11.5 m in Pbo (HR=0.630, p=0.01), with a median follow-up of 18.7 m (as of 26 Nov 2018). As of updated analysis based on a data cut-off of 18 March 2019, the median PFS (per investigator [INV]) was 22.9 m in Ven vs 11.4 m in Pbo (HR=0.587, p=0.001; Table 1), with a median follow-up of 22.7 m. Per INV, higher overall response (ORR, 84% vs 70%, p=0.009) and very good partial or better response (≥VGPR, 61% vs 40%, p<0.001; Table 2) rates were observed in Ven vs Pbo. Minimal residual disease negativity rate (by next-generation sequencing) was also higher in the Ven arm vs Pbo (MRD- [10-5], 13% vs 1%). Median duration of response was 23.4 m for Ven and 12.8 m for Pbo. In the overall population, median overall survival (OS) was not reached in either arm but continued to favor Pbo (HR 1.474, 95% CI=0.870-2.498). A total of 70 deaths have been reported, 51 (26%) in the Ven arm and 19 (20%) in the Pbo arm. In the safety population (N=289), the most common treatment-emergent adverse events (TEAEs; Ven/Pbo) were diarrhea (59%/48%), nausea (37%/22%), constipation (35%/31%), and fatigue (31%/32%). The most common Grade 3/4 TEAEs were neutropenia (18%/8%), pneumonia (17%/12%), anemia (16%/15%), thrombocytopenia (15%/30%), and diarrhea (15%/12%); 23%/12% discontinued Ven due to a TEAE. The rates of serious AEs (51%/51%) and serious infections (30%/28%) were comparable between arms. There were 69 deaths in the safety population: in the Ven arm, 14 were treatment-emergent (TE; treatment start to 30 days after discontinuation) and 36 were non-TE (>30 days after treatment discontinuation); in the Pbo arm, 1 was TE and 18 were non-TE. In the t(11;14) subgroup, median PFS has not been reached for pts receiving Ven, but was 9.3 m for Pbo (HR=0.095; per INV). In the t(11;14)-negative (neg) subgroup, median PFS was 22.4 m and 10.7 m for Ven and Pbo, respectively (HR=0.627; per INV). Median OS has not been reached in either arm for the t(11;14) and t(11;14)-neg subgroups, although the HR favored Ven in t(11;14) pts, and Pbo in t(11;14)-neg pts. Analyses indicate that low BCL-2 expression by IHC and high-risk cytogenetics (defined as t(4;14, t(14;16), or del(17p)) were associated with decreased PFS and OS in the Ven arm (Table 1). In the high-risk cytogenetics pts, median PFS was 11.4 m in both arms (HR=0.99), and median OS has not been reached in either arm but favors Pbo (HR=10.6). In the subgroup with low BCL-2 expression by IHC, median PFS was 11.7 m and 17.0 m for Ven and Pbo, respectively (HR=1.42), and median OS was 21.3 m in the Ven arm and not reached in Pbo (HR=4.58). Conclusions: Updated analysis of BELLINI continue to reflect a favorable benefit-risk profile in t(11;14) pts, with meaningful clinical responses and improvement in PFS, as well as a positive trend in OS in this subgroup when treated with Ven + Bd. Disclosures Moreau: Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria. Harrison:Janssen Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Consultancy, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: investigator on studies, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Cavo:sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations, Speakers Bureau; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; bms: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; novartis: Honoraria. De La Rubia:Janssen: Consultancy; Takeda: Consultancy; Celgene Corporation: Consultancy; AMGEN: Consultancy; AbbVie: Consultancy. Popat:Celgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses; Janssen: Honoraria, Other: travel support to meetings; Takeda: Honoraria, Other: travel, accommodations, expenses; GSK: Consultancy, Honoraria; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees. Gasparetto:Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Hungria:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Salwender:Amgen: Honoraria, Other: Travel or accommodations; Takeda: Honoraria, Other: Travel or accommodations; Bristol-Myers Squibb: Honoraria, Other: Travel or accommodations; Sanofi: Honoraria, Other: Travel or accommodations; Celgene: Honoraria, Other: Travel or accommodations; AbbVie: Honoraria; Janssen Cilag: Honoraria, Other: Travel or accommodations. Suzuki:Ono: Research Funding; BMS: Honoraria, Research Funding; Takeda: Honoraria; Janssen: Honoraria; Celgene: Honoraria. Gay:Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees. Mikala:Takeda: Honoraria; Roche: Honoraria; Novartis: Honoraria; Janssen: Honoraria; Celgene: Honoraria, Research Funding; Amgen: Honoraria; AbbVie: Honoraria, Research Funding. Punnoose:Genentech, Inc.: Employment; Roche: Other: Stock/stock options. Hong:Genentech Inc.: Employment, Equity Ownership; Roche: Equity Ownership. Sood:AbbVie: Employment, Other: Stock/stock options. Jalaluddin:AbbVie: Employment, Other: Stock/stock options. Ross:AbbVie: Employment, Other: Stock/stock options. Ward:AbbVie: Employment, Other: Stock/stock options. Maciag:AbbVie: Employment, Other: Stock/stock options. Kumar:Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Takeda: Research Funding. OffLabel Disclosure: Venetoclax is a BCL-2 inhibitor that is FDA-approved in some indications. This presentation will focus on venetoclax for treatment of multiple myeloma, which is not an approved indication.

Abstract Background: The anti-apoptotic proteins BCL-2 and MCL-1 promote multiple myeloma (MM) cell survival. Bortezomib (BTZ) can inhibit MCL-1 activity by stabilizing the MCL-1 antagonist, NOXA. Venetoclax is an orally bioavailable, highly selective BCL-2 inhibitor, which enhances BTZ efficacy in MM xenograft models. This Phase 1 study evaluates venetoclax with BTZ and dexamethasone (Dex) in patients (pts) with relapsed/refractory MM. Methods: Objectives include safety, pharmacokinetics, preliminary efficacy and maximum therapeutic dose of venetoclax with BTZ and Dex. A fixed dose of venetoclax ranging from 50 to 800 mg PO daily, according to dose cohort assignment, was given in combination in cycles (C) 1-11 and alone in C12 and beyond. Dose escalation decisions were made using the continual reassessment method. Pts received BTZ (1.3 mg/m2 SC, days [D] 1, 4, 8, 11) and Dex (20 mg PO, D1, 2, 4, 5, 8, 9, 11, 12) in cycles (C)1-8 (21D), then BTZ + Dex (D1, 8, 15, 22) in C9-11 (35D). Results: Forty-one pts were enrolled as of June 15, 2015 (pts in each cohort: 50 mg, n=3; 100 mg, n=5; 200 mg, n=6; 300 mg, n=7; 400 mg, n=6; 500 mg, n=7; 600 mg, n=5; 800 mg, n=2). Median age was 65 (38-79); 15/26 F/M. 14 were ISS stage I, 11 stage II, 11 stage III, 5 missing. Median (range) number of prior lines of therapy was 5 (1-15). Thirty-five pts had received prior BTZ (10 refractory), 34 prior lenalidomide (22 refractory); 29 had undergone stem cell transplantation. Based on FISH analysis, 5 pts had MM with t(11;14); 3 with t(4;14), 20 with del 17p, and 10 with del 13q. Treatment-emergent AEs occurring in ≥20% of pts were constipation (37%), diarrhea (37%), thrombocytopenia (32%), asthenia (29%), insomnia (29%), anemia (27%), peripheral neuropathy (27%), dyspnea (24%), peripheral edema (22%), and nausea (20%). Grade 3/4 AEs in ≥10% of pts were thrombocytopenia (20%), and anemia (17%). SAEs occurred in 18 pts; SAEs in ≥2 pts were cardiac failure, embolism, pyrexia, respiratory failure, sepsis, thrombocytopenia (n=2 each, no SAEs were venetoclax-related). Twenty-nine pts have discontinued treatment: 23 due to PD, 2 due to AEs [adenocarcinoma; cardiac and respiratory decompensation attributed to Dex (DLT at 300 mg)], and 4 withdrew consent. Three deaths occurred (all due to PD). No TLS occurred. In preliminary PK analyses (n=41), dose-normalized venetoclax exposure when given with BTZ+Dex was similar when compared to venetoclax monotherapy in MM as well as CLL and NHL pts. Forty of 41 pts were evaluable for efficacy. All responses occurred in BTZ sensitive or naïve pts. Median (range) duration or response was 5.9 (0-14.1) months in all pts, 8.5 (2.3-11.4) months in BTZ naïve pts, and 4.7 (0-14.1) months in BTZ-sensitive pts. Conclusions: Venetoclax with BTZ and Dex has an acceptable safety profile in heavily pretreated MM pts; no new safety signals were identified compared to other venetoclax studies. These early data suggest the combination of proteasome and BCL-2 inhibition resulted in anti-tumor activity. Responses were observed only in pts naïve or sensitive to prior BTZ (ORR = 100% and 58%, respectively) and occurred in all dose cohorts. The study is currently enrolling pts in the 1000 mg dose escalation cohort. Figure 1. Figure 1. Disclosures Moreau: Celgene, Janssen, Takeda, Novartis, Amgen: Membership on an entity's Board of Directors or advisory committees. Off Label Use: Venetoclax is an investigational drug that is not yet approved in this indication. Roberts:AbbVie and Genentech: Research Funding; Walter and Eliza Hall Institute of Medical Research: Employment. Agarwal:Amgen, Millennium: Consultancy; Celgene, Onyx: Speakers Bureau; AbbVie: Research Funding. Facon:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees; Onyx: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Pierre Fabre: Membership on an entity's Board of Directors or advisory committees. Kumar:Skyline, Noxxon: Honoraria; Celgene, Millennium, Onyx, Janssen, Noxxon, Sanofi, BMS, Skyline: Consultancy; Celgene, Millennium, Onyx, Novartis, Janssen, Sanofi: Research Funding. Touzeau:AbbVie: Research Funding. Darden:AbbVie: Employment, Equity Ownership. Morris:AbbVie: Employment, Equity Ownership. Ross:AbbVie: Employment, Equity Ownership. Salem:AbbVie: Employment, Equity Ownership. Munasinghe:AbbVie: Employment, Equity Ownership. Zhu:AbbVie: Employment, Equity Ownership. Leverson:AbbVie: Employment, Equity Ownership. Maciag:AbbVie: Employment, Equity Ownership. Enschede:AbbVie: Employment, Equity Ownership. Verdugo:AbbVie: Employment, Equity Ownership. Humerickhouse:AbbVie: Employment, Equity Ownership. Harrison:Celgene: Honoraria, Research Funding; Janssen: Research Funding, Speakers Bureau; AbbVie: Research Funding.

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 Background: Venetoclax (VEN) is a potent, selective, orally available small-molecule BCL-2 inhibitor that induces cell death in multiple myeloma (MM) cell lines and primary samples, particularly those with t(11;14), which mostly have a favorable high BCL-2, low BCL-XL, and low MCL-1 profile. Methods: In this Phase 1, open-label study, patients (pts) with relapsed/refractory (R/R) MM received VEN monotherapy. Objectives of the study were to assess safety, pharmacokinetics, maximum tolerated dose, recommended phase 2 dose, and efficacy (objective response rate [ORR], time to progression [TTP], and duration of response [DoR]) of VEN. After a 2-week lead in period with weekly dose escalation, VEN was given daily at final doses of 300, 600, 900, or 1200mg in dose escalation cohorts and 1200mg in the safety expansion. Pts who progressed during VEN monotherapy could receive VEN plus dexamethasone and continue in the study. Results: As of 01July2016, 66 pts were enrolled in the study (30 in dose escalation cohorts and 36 in safety expansion). Median age was 63 years and 39 (62%) pts were ISS stage II/III. The median number of prior therapies was 5 (range: 1-15), and 62 (94%) pts had received bortezomib (46 [70%] refractory), 62 (94%) received lenalidomide (51 [77%] refractory), and 50 (76%) had prior autologous stem cell transplant. Thirty (46%) pts had t(11;14) MM. Median time on VEN monotherapy for all pts was 2.5 months (.2-23); 17 (26%) elected to receive VEN and dexamethasone combination after disease progression for a median of 1.4 months (.1-11). Fifty-one (77%) pts discontinued the study for the following primary reasons: 39 related to disease progression, 5 due to AEs/toxicity, 2 withdrew consent, 1 was lost to follow up, and 4 for other reasons not specified. Common adverse events (AEs) in ≥20% of pts were nausea (48%), diarrhea (36%), neutropenia (32%), thrombocytopenia (32%), fatigue (27%), anemia (23%), back pain (21%), and vomiting (21%). Grade 3/4 AEs in ≥10% of pts were thrombocytopenia (26%), neutropenia (20%), lymphopenia (15%), anemia (14%), and decreased white blood cells (12%). Serious AEs in ≥2 pts were pneumonia (n=5), sepsis (3), pain, pyrexia, cough, and hypotension (2 each). Two pts experienced dose-limiting toxicities at 600mg of abdominal pain and nausea. Eight deaths were reported: 6 due to disease progression, 1 due to lung disorder, and 1 due to brain hemorrhage following injury; neither were considered by the investigator as related to VEN. Steady state VEN exposures were approximately dose proportional at all doses but 900mg. As of 20July2016, ORR for all pts on VEN monotherapy was 21% (14/66) and 10 (15%) achieved very good partial response (VGPR) or better (2 stringent complete response [sCR], 2 CR, 6 VGPR) (Figure); median DoR and TTP was 9.7 and 2.6 months, respectively. Most objective responses (12/14 [86%]) were reported in the subset of pts with t(11;14) MM. In this group, ORR was 40% (12/30) and 27% (8/30) achieved a response of ≥VGPR; median DoR for pts with t(11;14) was 9.7 months (95% CI: 6.3, -). Pts who achieved at least minimal response in the t(11;14) group (14/30) had a median of 4 prior therapies and were mostly refractory to bortezomib, lenalidomide, or double refractory (71% [10/14] each). For two pts with response in the non-t(11;14)/undetermined group, 1 had a translocation of chromosome 14 with an unidentified partner, and the other had no cytogenetics data available. DoR was 9.5 and 7.2 months in these pts and both are still ongoing. Median TTP for pts with or without/undetermined t(11;14) was 6.6 and 1.9 months, respectively. The median best percent change in primary M protein for pts with t(11;14) (n=23) was -53% vs +11% in the non-t(11;14)/undetermined group (n=23). Additional biomarker subgroup analyses (n=32) showed that efficacy was primarily observed in pts with myeloma cells expressing a favorable BCL-2 family expression profile (high BCL-2, low BCL-XL, low MCL-1) by immunohistochemistry, which was significantly enriched in the t(11;14) population. Indeed, although high BCL-2 expression was observed in a majority of bone marrow core biopsy samples (88%), the t(11;14) subgroup was enriched (81% vs 25%) for tumors expressing high BCL-2, low BCL-XL, and low MCL-1. Conclusions: VEN monotherapy has an acceptable safety profile and clear anti-myeloma activity in pts with R/R MM, primarily with t(11;14) having a high BCL-2, low BCL-XL and low MCL-1 expression levels. Figure Figure. Disclosures Kumar: Janssen: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Onyx: Consultancy, Research Funding; Glycomimetics: Consultancy; AbbVie: Research Funding; Array BioPharma: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Kesios: Consultancy; BMS: Consultancy. Kaufman:Novartis: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Pharmacyclics: Consultancy; Incyte: Consultancy. Mikhael:Abbvie: Research Funding; Celgene: Research Funding; Onyx: Research Funding; Sanofi: Research Funding. Facon:Amgen: Consultancy, Speakers Bureau; Novartis: Consultancy; Bristol: Consultancy; Millenium/Takeda: Consultancy; Janssen: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Karyopharm: Consultancy. Benboubker:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Moreau:Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Novartis: Honoraria; Amgen: Honoraria. Alzate:AbbVie: Employment. Ross:AbbVie: Employment, Equity Ownership. Dunbar:AbbVie Inc.: Employment, Other: may own stock. Xu:AbbVie: Employment. Agarwal:AbbVie: Employment. Leverson:AbbVie: Employment, Other: Shareholder in AbbVie. Maciag:AbbVie: Employment. Verdugo:AbbVie: Employment, Other: may own stock. Touzeau:AbbVie: Research Funding.