ALBERT

Description: Introduction: Venetoclax (VEN) based therapy has become a standard of care in front line and relapsed-refractory (R/R) CLL based on favorable efficacy and toxicity. Whereas prospective data regarding activity of therapies following ibrutinib (IBR) or idelalisib (IDE) are available in the settings of progression (VEN, non-covalent BTKi) and intolerance (acalabrutinib), how best to manage patients (pts) who discontinue (dc) VEN remains a key unanswered question. With the increased use of VEN in early lines of therapy (LOT; CLL 14, MURANO), the activity of BTK inhibitors (BTKi) and cellular therapies following VEN becomes a critical issue. No prospective study has addressed this question, and currently reported VEN clinical trials have limited information about subsequent treatments. While recent data describe VEN resistance mechanisms (Guieze 2018, Blombery 2019), the impact of VEN resistance on efficacy of post VEN therapies is unknown. To address this gap, we conducted an international study to identify a large cohort of pts who dc VEN and have been subsequently treated. Methods: We conducted an IRB approved multicenter (31 US, EU, South American sites, in partnership with UK CLL Forum and CORE registry), retrospective cohort study of CLL pts who dc VEN for any reason. We examined demographics, dc reasons, responses, survival, adverse events (AEs) and activity of post VEN therapies. Primary endpoints were overall response rate (ORR) and progression free survival (PFS) for the post VEN treatments stratified by treatment type (BTKi, PI3Ki and cellular therapy: CAR-T or alloHSCT). ORR was defined by iwCLL criteria and PFS was defined from VEN dc to disease progression (PD), death, or last follow up for next treatment. Pts were further stratified by BTKi (resistant / intolerant) and PI3Ki exposure prior to VEN. PFS-2 was defined as time from VEN start to tumor progression on IBR or death from any cause. Results: 326 CLL pts who dc VEN in the front line (4%) and R/R settings (96%) were identified. The cohort was 69% male, 87% white, median (med) age 66 (38-91) at VEN start, 27% treated with VEN based combinations (n=88, med 6 cycles anti-CD20 abs). Pre VEN prognostic features: 82% IGHV unmutated (n tested=166), 47% del17p (n=306), 45% TP53 mut (n=217), 39% complex karyotype (n=273), 23% BTK mut (n=79), 18% NOTCH1 mut (n=103), 10% PLCγ2 mut (n=74). Pts received med 3 therapies (0-11) prior to VEN; 40% were BTKi naïve (n=130), 60% were BTKi exposed (196) and 81% were IDE naïve (n=263). Most common reasons for VEN dc were PD (38%), AE (20%), Richter's transformation (RT, 14%), 8% pt preference, and HSCT 5%. Of 326 pts who dc VEN, 188 (58%) were treated with a subsequent LOT, 61 are alive and untreated and 77 died prior to a subsequent LOT. Post VEN sequencing analyses focused on BTKi, PI3Ki and cellular therapy (CAR-T or alloHSCT) activities following VEN dc (Table1). ORR to BTKi was 84% (n=44) vs. 54% (n=30, p

Description: Introduction: Venetoclax (Ven) is approved for relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL) as monotherapy (Ven mono) or in combination (Ven paired) with rituximab based on clinical trials with selected patients (pts) and limited ibrutinib exposure. Whether Ven paired is superior to Ven mono, patterns of care, and outcomes following Ven discontinuation are unknown. Further, better delineation of adverse events (AEs) when Ven is used outside of clinical trials is needed. To address these gaps, we conducted a multicenter, international study in partnership with CLL Collaborative Study of Real World Evidence (CORE) and UK CLL Study Forum examining the clinical experience of 348 Ven treated CLL pts, representing the largest series of Ven treated pts reported to date. Methods: We conducted a retrospective cohort analysis of CLL pts treated with Ven across 24 US and 42 UK academic and community centers. We examined demographics, baseline disease characteristics, dosing, AEs, TLS risk and outcomes, response rates, outcomes (overall survival (OS) and progression free survival (PFS)), and tx sequencing. TLS events were defined by Howard criteria. PFS and OS were estimated by the Kaplan Meier method. Comparisons of outcomes used the Log Rank test. Univariate and multivariate analyses were performed with COX regression. All other comparisons were descriptive. Results: Of these 348 CLL pts, 94% were R/R, median age 67 years (range:37-91), 69% male, 85% white, and 73% Rai stage ≥2. 19% received Ven on clinical trial. 79% had Ven mono; Ven was paired most commonly with anti-CD20 (n=51) and ibrutinib (n=10). Pts received a median of 3 tx (range 0-15) before Ven; 78% received ibrutinib, 29% received PI3Ki, 20% had ≥2 prior kinase inhibitors, and 68% had chemoimmunotherapy. Median time from most recent tx to Ven start was 1.1 months (range 0-62). Pre-Ven prognostic markers included 43% del17p, 34% TP53 mutated, 24% del11q, 38% complex karyotype (≥ 3 abnormalities), and 84% IGHV unmutated (Table 1). TLS risk was low in 38%, intermediate in 34% and high in 28%. During ramp up, TLS was observed in 10% (22 lab, 9 clinical TLS events, 3 missing data). Following dose escalation, 70% achieved a stable Ven dose of 400 mg, 33% required ≥ 1 dose interruption and 27% required ≥ 1 dose reduction. AEs included grade 3 neutropenia 39%, grade 3 thrombocytopenia 29%, infections 25%, grade ≥ 2 diarrhea 7.8%, and neutropenic fever 7.7%. AEs were similar whether treated on or off clinical trial. The ORR to Ven mono, Ven paired was 81% (34% CR), 86% (29% CR). With a median follow-up of 14.2 months, median PFS and OS were not reached (12 month PFS 74%, OS 82%). Figure 1 depicts PFS stratified by Ven mono vs. paired, clinical trial vs. clinical practice, del17p status, and complex karyotype. Pts who discontinued Ven due to AEs had better OS compared with those who discontinued due to progression or Richter Transformation (RT) (Median OS 47 vs. 15.1 vs. 8.6 months, respectively). In multivariate analyses, complex karyotype was the only independent predictor of PFS (HR 2.8, p

Description: Background: Carfilzomib (Cfz), lenalidomide, and dexamethasone synergize to provide an impressive overall response rate (ORR) in upfront treatment of multiple myeloma (MM) (Jakubowiak et al 2012). The ORR to Cfz+dexamethasone (Cfz-Dex) as first-line therapy is unknown. We hypothesized that sequential treatment with Cfz-dex and BiRD would improve provide similar ORR and improve tolerability. A protocol of Cfz-Dex, consolidation with BiRd (Clarithromycin(Biaxin¨), Lenalidomide/(Revlimid¨), dexamethasone), and lenalidomide maintenance (Len) was conducted to evaluate ORR and safety as induction therapy for MM. Methods: Forty patients (pts) with symptomatic untreated MM were enrolled in a phase 2 study of Car-BiRd. Car-BiRd therapy is: Cfz IV over 30 min on Days 1, 2, 8, 9, 15, 16 of a 28-day cycle at a dose of 20mg/m2 on days 1, 2 of the 1st cycle only and 45mg/m2 for each dose thereafter and dex 40mg on D1, 8, 15, 22. After the first 26 pts were enrolled, the protocol was amended to increase the Cfz from 45 to 56mg/m2. Echocardiography and spirometry were performed prior to study entry and serum brain natriuretic peptide (BNP) was followed monthly to evaluate for heart or lung toxicity. Cfz-dex was continued until plateau in disease response, defined as unchanged M-protein for 2 cycles. Elective stem cell collection was then performed in transplant eligible pts and consolidation with BiRd initiated. Transplant ineligible pts proceeded directly to BiRd. BiRd is: Clarithromycin 500mg BID, lenalidomide 25mg daily on D1-21, and dex 40mg on D1, 8, 15, 22 of 28-day cycle. BiRd was continued until a 2nd response plateau after which lenalidomide maintenance (Len) at 10mg daily D1-21 of 28 day cycle was continued until disease progression or intolerability. Results: 36 pts completed at least 1 cycle and were evaluable for response. 58% of pts were ISS II/III. High-risk cytogenetics and unfavorable MyPRS score were found in 62% and 21% of pts, respectively. Median study follow-up was 66.2 weeks (range 3.7-114.7). Maximum response to the Cfz-dex, BiRd, and Len is shown in Table 1. Median time to PR was 1 cycle. Median time to maximum response with Cfz-dex, BiRD, and Len was 2, 2, and 4 cycles respectively. At last audit, 8 (22%) pts remain on Cfz-Dex; 21 (58%) reached plateau and received BiRd. Of the pts that received BiRd, 9 (43%) improved categorical response and 19 (90.5%) received Len. Two (11%) pts deepened response to CR while on Len. 97.5% of pts are alive and 82.5% without progression at last follow-up. One pt died after coming off study (withdrew consent) from sepsis during elective autologous stem cell transplant. Pts with high risk cytogenetics had a trend towards a shorter progression free survival (PFS), with median 71.7 weeks vs not reached (NR) (P = 0.058). Similar results were seen with unfavorable MyPRS score with a shorter median PFS at 71.7 weeks vs NR (P = 0.094). 17 pts had stem cell harvest following Cfz-dex. All collected stem cells to support at least two transplants, with median 14.5 x 10^6 (range 7.06-27) CD34/kg in a median of 1 (range 1-2) apheresis session. 18 pts (46.2%) have come off study, 6 (15%) for disease progression (2 during CfzDex , 1 during BiRD, 3 during Len) and 5 pts (12.5%) due to toxicity: 3 pts for renal failure [2 Grade 2, I grade 3, all with renal recovery after discontinuation, all attributable to Cfz]; 1 pt due to Grade III CHF [attributable to Cfz with recovery]; 1 pt with Grade III Thromboembolic [attributable Len]. There was no correlation between pre-study cardiac and lung function, or serial BNP, with toxicities. Seven (17.9%) pts came off study for noncompliance, lost to follow up, investigator discretion, or withdrew consent (Cfz-dex: 4, BiRD: 1, Len: 2). Discussion: This is the first prospective study evaluating induction response to Cfz/Dex in MM. Cfz/Dex is safe and active, with ORR of 91.7% and rate of 〉=VGPR of 55.6%, despite the majority with a high-risk cytogenetics. Cfz-dex did not hinder stem cell harvest. ORR improved with lenalidomide-based consolidation and maintenance, with CR rate 〉 50%. Baseline heart/lung function or serial BNP change did not predict emerging toxicities. Table 1: Maximum Response For Car-BiRD Phase: Response Category Car-Dex BiRD Lenalidomide N = 36 N = 21 N = 19 PD 0 1 (4.8) 0 SD 3 (8.3) 0 0 PR 13 (36.1) 1 (4.8) 1 (5.3) VGPR 17 (47.2) 12 (57.1) 8 (42.1) CR 1 (2.8) 0 0 SCR 1 (2.8) 5 (23.8) 8 (42.1) ICR 1 (2.8) 2 (9.5) 2 (10.5) 〉=PR 91.7 95.2 100 〉=VGPR 55.6 90.4 94.7 〉=CR 8.4 33.3 52.6 Disclosures Mark: Onyx: Research Funding, Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Off Label Use: Carfilzomib is not approved for first-line treatment of myeloma. . Rossi:Celgene: Speakers Bureau. Pekle:Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Perry:Celgene: Speakers Bureau. Coleman:Onyx: Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Niesvizky:Onyx: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Description: Background Carfilzomib (Cfz) synergizes with lenalidomide and dexamethasone (Len-dex) to provide impressive response rates as upfront treatment of multiple myeloma (MM) (Jakubowiak et al 2012). The addition of clarithromycin to Len-dex has shown superior time to progression compared to Len-dex alone (Gay et al 2010). We hypothesized that sequential treatment with Cfz-dex and BiRD would lead to enhanced efficacy, response duration, and tolerability. We thus tested a sequential approach of upfront carfilzomib / dexamethasone, consolidation with BiRd, and lenalidomide maintenance to evaluate overall response and safety as first line therapy for MM. Methods Twenty-four patients (pts) with symptomatic untreated MM were enrolled in a single institution study to evaluate the efficacy and tolerability of Car-BiRd. Car-BiRd therapy is: Cfz IV over 30 minutes on Days 1, 2, 8, 9, 15, 16 of a 28-day cycle at a dose of 20mg/m2 on days 1, 2 of the 1st cycle only and 45mg/m2 for each successive dose thereafter and dex 40mg on D1, 8, 15, 22. Cfz-dex was continued until plateau in disease response defined as unchanged M-protein for 2 cycles. Elective autologous stem cell collection was then performed per physician and patient discretion and consolidation with BiRd initiated. Transplant ineligible pts proceeded directly to BiRd. BiRd is: Clarithromycin 500mg BID, lenalidomide 25mg daily on D1-21, and dex 40mg daily D1, 8, 15, 22 of 28-day cycle. Therapy was continued until a 2nd plateau in disease response after which lenalidomide maintenance at a dose of 10mg daily D1-21 of 28 day cycle was continued until disease progression or intolerability. Results 24 pts have currently been enrolled; 23 have completed at least 1 cycle of therapy and were evaluable for response. Sixteen pts (67%) harbored high-risk cytogenetics, as defined by the presence of one or more of the following on iFISH: del 17p, gain 1q, del 1p, t(4;14), t(14;16), or complex karyotypic abnormalities. Median study follow-up was 30.8 weeks (range 4.5-62.2). Response to the Car-BiRD regimen was: overall response rate (ORR) 87%, stringent complete response (sCR) 13%, very good partial response (VGPR) 48%, partial response (PR) 26%, stable disease (SD) 13%. Maximum response to the Cfz-dex induction was: ORR 87%, sCR 9%, VGPR 39%, PR 35%, SD 13%. Median time to PR and maximum response with Cfz-dex was 2 cycles (range 1-2) and 4 cycles (range 1-5) respectively. Median M-spike percentage decrease with Cfz-dex was 92% (range 13-100%). Twelve pts thereafter received BiRD consolidation with 5 pts (41%) further decreasing the M-spike by a median of 8% (range 1-45%). A median of 3 cycles (range 2-7) of BiRD was given until a 2nd response plateau was achieved. Seven pts subsequently received lenalidomide and all have maintained their response after a median of 5 cycles (range 1-8) of follow-up. Seven pts (30%) have come off study, 2 (8%) secondary to disease progression (1 during Car-Dex and 1 during BiRD) and 5 pts (22%) due to toxicity (2 pts due to Grade III renal failure, both attributable to Cfz, and 2 pts due to Grade III CHF during Cfz-Dex, 1 attributable to Cfz; 1 pt with Grade III Thromboembolic event during BiRD, attributable to Len-dex). Discussion This is the first prospective study evaluating the response to induction Cfz/Dex in treatment-naïve MM. Cfz/Dex therapy appears safe and effective in newly diagnosed myeloma patients. Responses deepen with subsequent IMiD(R)-based consolidation and maintenance. Toxicities due to each component of the regimen were manageable. The ORR of 87% and rate of VGPR or better of 61% in group with a high percentage of unfavorable cytogenetics compares favorably to similar studies using 1st generation proteasome inhibitor combinations, and may continue to improve with longer study follow-up. Disclosures: Mark: Onyx: Research Funding, Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Off Label Use: Carfilzomib is not approved for front line use in myeloma. Rossi:Celgene: Speakers Bureau. Zafar:Onyx: Speakers Bureau; Millennium: Speakers Bureau; Celgene: Speakers Bureau. Pekle:Millennium: Speakers Bureau; Celgene: Speakers Bureau. Niesvizky:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Onyx: Consultancy, Honoraria, Research Funding, Speakers Bureau; Millennium: The Takeda Oncology Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Description: Introduction REGN1979 is an anti-CD20 x anti-CD3 bispecific IgG4 antibody (Ab) modified to reduce Fc binding. Engaging both targets results in CD20-specific, local T-cell activation and cytotoxicity, a mechanism of action distinct from standard anti-CD20 Abs. We report updated promising efficacy results of a Phase 1 trial of REGN1979 in patients (pts) with relapsed/refactory (R/R) B-NHL previously treated with anti-CD20 Abs. Methods The primary objectives of the study are to determine safety, tolerability, and occurrence of dose limiting toxicities (DLTs). Other objectives include assessment of preliminary antitumor activity, pharmacokinetics (PK), and pharmacodynamics. Eligible pts with R/R NHL must have received at least 1 prior CD20-directed therapy. Treatment consists of 12 weekly doses of REGN1979 followed by every 2 week dosing for 12 doses for a total of 36 weeks. Guidelines are provided for management of cytokine release syndrome (CRS) and include steroids and/or tocilizumab at investigator discretion. Results As of June 1, 2018, 54 pts with B-NHL were treated with REGN1979 monotherapy: DLBCL (pt number [n]=30), FL (n=16), MCL (n=5), MZL (n=2), and WM (n=1). The median number of prior regimens was 3 (range, 1-11); 41 pts were refractory to their last prior systemic therapy, 18 had bulky disease, and 6 had prior HSCT. Pts were treated with REGN1979 0.03-27 mg and received a median of 7 (range, 1-24) doses. Eight pts remain on treatment, 13 completed treatment, and 33 discontinued therapy prior to the planned 36 wks (majority [n=22] due to progressive disease [PD]). There have been no DLTs to date. The most common treatment-related treatment-emergent adverse events (TR-TEAEs) included infusion-related reactions (IRR) or CRS; 26 pts experienced CRS (Grade 1-2, n=23; Grade 3, n=3) with a median duration of CRS of 2 (range 1-15) days. Six pts received tocilizumab. The severity of CRS symptoms declined through optimized pre-medication even with REGN1979 dose escalation. Other common Grade ≥3 TR-TEAEs were lymphocytopenia/ decreased lymphocyte count (n=8); neutropenia/ decreased neutrophil count (n=7); and thrombocytopenia/ decreased platelet count, hypotension, hypophosphatemia, and anemia (each n=3). Seventeen pts experienced a nervous system event including headache, dizziness, paraesthesia, dysgeusia, and peripheral neuropathy with no Grade ≥3 events; no neurologic event required termination of study drug. Seven pts died on study: PD (n=5), gastric perforation (n=1), and cardiac arrest (n=1). TEAEs leading to premature discontinuation of REGN1979 were Grade 3 fatigue (n=1), Grade 3 hemolysis (n=1), and Grade 2 pyrexia/Grade 2 tachycardia (n=1). Among 27 pts treated with REGN1979 ≥5 mg (dose associated with tumor killing in pre-clinical data), the overall response rate (ORR) was 55.6% (5 complete response [CR] and 10 partial response [PR]; Table/Figure). Responses were seen in 7/7 FL Grade 1-3a pts (5 CR, 2 PR), 6/15 DLBCL pts (all PR), 2/2 MCL pts (all PR). At 18 mg and 27 mg of REGN1979, 4 of 4 pts with DLBCL had best response of PR. Post data cut-off, 1 pt with a DLBCL best response of PR converted to CR. PK and pharmacodynamic assessments suggest that for pts treated with REGN1979 5-18 mg, best exposures in the first 3 weeks appear to linearly increase with dose. In pts treated with up to REGN1979 18 mg, a maximum mean Ctrough of 1.6 mcg/mL was observed in the first 3 weeks of weekly dosing. Studies of peripheral blood biomarkers demonstrated depletion of peripheral B lymphocytes, transient margination of circulating T-cells, and elevated circulating cytokines following REGN1979 dosing. Increased peak cytokine levels (IL-6, IL-10, and TNF-alpha) were observed in pts with CRS. Immunohistological analysis of malignant lymph node tissue demonstrated a decrease of CD20 expression in responding pts; among the responders, subsequent relapse was associated with either maintenance of CD20 expression or further CD20 loss, suggesting antigen-dependent and independent disease escape mechanisms. Conclusions REGN1979 displays efficacy and an acceptable safety profile in pts with R/R B-NHL. Most TR-TEAEs were IRR/CRS and have been well managed with supportive care. No significant neurological toxicity has been observed. At doses of 5-27 mg of REGN1979, the preliminary ORR was 100% in pts with FL Grade 1-3a and 40.0% in pts with DLBCL. This promising efficacy warrants further clinical investigation. Disclosures Bannerji: Regeneron Pharmaceuticals, Inc.: Consultancy; AbbVie, Inc.: Consultancy. Arnason:Regeneron Pharmaceuticals, Inc.: Consultancy. Advani:Bayer Healthcare Pharmaceuticals: Other: Consultancy/Advisory Role; Janssen Pharmaceutical: Other: Institutional Research Support; Bristol Myers Squibb: Other: Consultancy/Advisory role and Institutional Research Support; Pharmacyclics: Other: Institutional Research Support; Takeda: Other: Consultancy/Advisory Role; Millenium: Other: Institutional Research Support; Gilead/Kite: Other: Consultancy/Advisory Role; Infinity: Other: Institutional Research Support; Merck: Other: Institutional Research Support; Forty Seven, Inc: Other: Institutional Research Support; Cell Medica: Other: Consultancy/Advisory Role; Agensys: Other: Institutional Research Support; Celgene: Other: Institutional Research Support; Seattle Genetics: Other: Consultancy/Advisory role, Institutional Research Support; Kura: Other: Institutional Research Support; Roche/Genentech: Other: Consultancy/Advisory Role, Institutional Research Support; Kyowa: Other: Consulting/Advisory Role; Regeneron Pharmaceuticals, Inc.: Other: Institutional Research Support; Autolus: Other: Consultancy/Advisory Role; AstraZeneca: Other: Consultancy/Advisory Role. Brown:Acerta / Astra-Zeneca: Membership on an entity's Board of Directors or advisory committees; Verastem: Consultancy, Research Funding; Pharmacyclics: Consultancy; Celgene: Consultancy; Genentech: Consultancy; TG Therapeutics: Consultancy; Morphosys: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Abbvie: Consultancy; Gilead: Consultancy, Research Funding; Sun Pharmaceutical Industries: Research Funding; Sunesis: Consultancy; Loxo: Consultancy; Beigene: Membership on an entity's Board of Directors or advisory committees; Invectys: Membership on an entity's Board of Directors or advisory committees; Roche/Genentech: Consultancy; Boehringer: Consultancy. Allan:Genentech: Membership on an entity's Board of Directors or advisory committees; Verastem: Membership on an entity's Board of Directors or advisory committees; Sunesis: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees; Acerta: Consultancy. Ansell:Bristol-Myers Squibb: Research Funding; Affimed: Research Funding; Regeneron: Research Funding; Merck & Co: Research Funding; LAM Therapeutics: Research Funding; Seattle Genetics: Research Funding; Trillium: Research Funding; Celldex: Research Funding; Takeda: Research Funding; Pfizer: Research Funding. O'Brien:Kite Pharma: Research Funding; Aptose Biosciences Inc.: Consultancy; Pharmacyclics: Consultancy, Research Funding; GlaxoSmithKline: Consultancy; Astellas: Consultancy; Sunesis: Consultancy, Research Funding; Alexion: Consultancy; Amgen: Consultancy; TG Therapeutics: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Vaniam Group LLC: Consultancy; Regeneron: Research Funding; Janssen: Consultancy; Celgene: Consultancy; Abbvie: Consultancy; Acerta: Research Funding; Gilead: Consultancy, Research Funding. Chavez:Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Research Funding; Kite: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Humanigen: Consultancy. Lowy:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Charnas:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Sternberg:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Ambati:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Adriaens:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Ufkin:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Yan:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Li:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Navarro:Regeneron Pharmaceuticals, Inc.: Employment. Gasparini:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Jankovic:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Fiaschi:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Zhang:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Hamon:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Thurston:Regeneron Pharmaceuticals, Inc.: Employment, Equity Ownership. Topp:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; F. Hoffmann-La Roche Ltd: Membership on an entity's Board of Directors or advisory committees, Research Funding; Boehringer Ingelheim: Research Funding; Regeneron Pharmaceuticals, Inc.: Honoraria, Research Funding.

Description: Introduction: Heparin-induced thrombocytopenia (HIT) is an immune mediated, adverse effect related to both unfractionated heparin (UFH) and low-molecular weight heparin (LMWH). HIT may result in significant morbidity and mortality. The serotonin release assay (SRA) is utilized in conjunction with clinical information to diagnosis HIT. Employment of the pretest clinical scoring system, known as the “4Ts”, classifies patients as having a low, intermediate or high probability for developing HIT. Previous investigators have reported clinically diagnosed HIT in patients with a negative SRA. However, there is no systematic study evaluating such a group of patients. We determined the frequency of thromboses in SRA negative patients and determined the correlation between the 4T score in patients with and without thromboses. Methods: We report a descriptive, single institution, retrospective study of 181 consecutive samples over the course of one year sent to the Coagulation Laboratory of St. Louis University for the work up of suspected HIT. A total of 142 patients were eligible. Patients with SRA negative samples were evaluated for evidence of thrombosis. Diagnosis of a thrombotic event was made by computed tomography (CT), venous Doppler ultrasonography (US), and ventilation-perfusion scanning (V/Q). Defined patient study groups were: all evalulable patients (PALL), patients with thromboses (TPOS) and patients without thromboses (TNEG). Analyses, between each patient group, the 4T score, mean platelet count prior to heparin therapy, and mean platelet nadirs were performed. Results: The overall incidence of proven thromboses in evaluable SRA negative patients was 14.8% (n=21). Of the 21 thromboses, 17(81.0%) were deep venous thromboses (DVT), 3(14.3%) were DVT and pulmonary embolus (PE), and 1(0.7%) was an isolated PE. A significant difference in 4T score was observed between TPOS vs PALL (p

Description: Background Pomalidomide and Carfilzomib (Cfz) are two recently approved agents for the treatment of multiple myeloma (MM) that has relapsed after prior therapy including an IMiD and bortezomib. The sequencing of these agents to achieve maximum tumor reduction is thus far not known. We have previously reported response data from the combination clarithromycin, pomalidomide, dexamethasone (ClaPD) for relapsed or refractory MM. (Mark et al, ASH 2012). We examined the subset of these patients that had received a Cfz-based regimen prior to ClaPD as well as the subset of patients that received a Cfz-based regimen after ClaPD to determine whether the sequence of agents had any impact on response. Methods One hundred nineteen patients with heavily pretreated RRMM were enrolled into a single-institution study to investigate the effectiveness and tolerability of ClaPD. Eligible subjects had at least 3 prior lines of therapy, one line of which must have included lenalidomide. ClaPD is clarithromycin 500mg twice daily; pomalidomide 4mg for days 1-21, and dexamethasone 40mg on days 1,8,15,22 of a 28-day cycle. Two subsets of patients were compared: 1) Subjects that had received treatment with a Cfz-based prior to ClaPD (CP) and 2) Subjects that had received a Cfz-based therapy after progression on ClaPD (PC). Disease response evaluation was performed monthly with immunoelectrophoresis and free light chain analysis; bone marrow biopsy with skeletal imaging was used to confirm MM progression or complete response (CR). Results Fourteen patients comprised CP and 20 in PC. Patients in the CP group were more heavily pre-treated with a median of 6 (range 3-15) lines of therapy, as compared to 5 lines (range 3-10) for PC. Responses are shown in Table 1. Median cycles of ClaPD and Cfz received in PC was 6.5 (range 2-16) and 5 (1-14), respectively. Median cycles of Cfz and ClaPD in the CP group was 8 (1-19) and 5 (1-23), respectively. CR complete response; VGPR: very good partial response; PR: partial response; SD: stable disease; PD: progressive disease; ORR: overall response rate Conclusions ClaPD and a Cfz-based regimen appear to have equally effective response regardless of sequence in salvage chemotherapy. Somewhat deeper responses are seen with ClaPD after Cfz as compared to Cfz after ClaPD, which is intriguing given that the CP group had more prior lines of treatment than PC. Longer follow-up to analyze duration of the response is needed prior to concluding which sequence (PC vs CP) is more effective. This data supports the use of pomalidomide after carfilzomib failure and vice-versa as potent salvage therapeutic options. Disclosures: Mark: Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millennium: Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Onyx: Research Funding, Speakers Bureau. Rossi:Celgene: Speakers Bureau. Zafar:Celgene: Speakers Bureau; Millennium: Speakers Bureau; Onyx: Speakers Bureau. Pekle:Celgene: Speakers Bureau; Millennium: Speakers Bureau. Niesvizky:Millennium: The Takeda Oncology Company: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Onyx: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Description: BACKGROUND: Tumor cell survival critically depends on heterotypic communications with non-malignant cells in the microenvironment. Most of these signals converge on the activation of the transcription factor NF-κB that regulates complex cellular functions, including apoptosis, cell survival and proliferation. Even if NF-kB is constitutively active in most malignancies, including chronic lymphocytic leukemia (CLL), and plays a major role in tumorigenesis, there are no currently approved drugs to target it. IT901 has been recently reported as a novel NF-kB inhibitor, showing efficacy in a non-tumor context1. AIM OF THE WORK: The aim of this work is to test the efficacy of IT901 in CLL and in its more aggressive transformation, Richter syndrome (RS), which represents an unmet therapeutic need. The molecular mechanisms of action of IT901 in leukemic cells are studied, alongside its effects on cells belonging to CLL microenvironment. RESULTS: IT901 induces apoptosis in primary leukemic cells in a dose- and time-dependent manner, showing significant efficacy after 24h of treatment. The apoptotic response is independent of the prognostic subgroup. Conversely, IT901 has minimal impact upon normal B cells. Treatment of CLL cells with IT901 interferes with NF-kB transcriptional activity, resulting in a diminished binding of both p50 and p65 to DNA. Moreover, biochemical analyses indicate a diminished expression of these subunits in the nucleus, as well as of the whole NF-kB complex in the cytoplasm. At the molecular level, compromised expression of NF-kB triggers activation of the Caspase-3 apoptotic pathway, with increased expression of pro-apoptotic proteins (e.g., Bim), paralleled by a diminished expression of the anti-apoptotic ones (e.g., XIAP). Concomitantly, a prominent increase in mitochondrial ROS is evident, providing a link between IT901 effects and induction of apoptosis. Recent data reported the involvement of NF-kB as a transcriptional controller of metabolic pathways promoting oxidative phosphorylation in cancer cells. In line with NF-kB constitutive activation in CLL, dynamic measurement of the energetic profile, indicates a reliance on oxidative phosphorylation, with limited glycolytic capacity. After IT901 treatment, there is a dramatic drop in mitochondrial respiration, with compromised ATP production and a net increase in proton leak, suggesting that primary CLL cells are trying to compensate impaired respiration by shifting to glycolysis. This metabolic response is mediated at the transcriptional levels, as IT901 induces a down-modulation of the genes involved in mitochondrial respiration (e.g., ATP5A1) and a concomitant up-modulation of the ones involved in glucose uptake and lactate transport (e.g., GLUT1). The CLL microenvironment is critical for disease progression and for providing protection from drug-induced apoptosis. Therefore it is important to consider the effects of novel drugs also on non-neoplastic bystander elements. Nurse-like cells (NLC) are a population of monocyte-derived activated macrophages that nurtures CLL cells via soluble and cell contact dependent mechanisms. These interactions are known to activate NF-kB signaling in both partners. Consistently, IT901 inhibited nuclear localization of the p65 subunit in NLC and shifted their polarization towards an M1-phenotype. These results are confirmed using a xenograft model. The Mec-1 cell line was injected into NSG mice and left to engraft for 2 weeks before beginning treatment. Animals treated with IT901 are characterized by decreased tumor growth and leukemic cells diffusion compared to controls, as shown by a diminished number of leukemic cells in kidneys, liver and spleen. Finally, IT901 shows promising effects in a small cohort of leukemic cells obtained from RS patients, inducing significant apoptosis by interfering with the expression and nuclear localization of NF-kB. CONCLUSIONS: Altogether, these results indicate that IT901 blocks NF-kB transcriptional activity. This effect is followed by rapid and marked decrease in genes supporting oxidative phosphorylation, causing mitochondrial damage, ROS release and induction of intrinsic apoptosis. Moreover, IT901 interrupts the support that CLL obtains from the microenvironment. Thus, targeting NF-kB by means of IT901 may be effective for CLL, and possibly even RS patients. 1. Y. Shono et al., Cancer Res76, 377 (Jan 15, 2016). Disclosures Furman: Genentech: Consultancy; Janssen: Consultancy; Abbvie: Consultancy, Honoraria; Gilead Sciences: Consultancy; Pharmacyclics: Consultancy, Speakers Bureau.

Description: Background- Currently combination regimens for induction therapy based around a proteasome inhibitor (PI), an immunomodulatory agent (IMiD) or both are standard for the treatment of newly diagnosed multiple myeloma (NDMM). In phase II studies the combination of Carfilzomib, Lenalidomide and Dexamethasone (Dex) has led to very high rates of overall and deep responses as induction therapy (Jakubowiak Blood 2012). According to the Norton-Simon hypothesis, the sequential, dose-dense use of agents that are not cross-resistant and have minimal overlapping toxicity may eliminate the emergence of residual inherently resistant sub-clones which are responsible for relapse. A sequential approach may also allow for medications to be administered at higher doses and the incorporation of more active agents into an initial therapeutic platform than can be tolerated in a single combinatorial induction approach. To date limited research has been done which evaluates a planned sequential therapeutic protocol built around the successive administration of a highly active PI and IMiD for NDMM. We conducted a phase II study evaluating high dose Carfilzomib and Dex induction (Kd) followed by Lenalidomide, clarithromycin and Dex (BiRD) consolidation and Lenalidomide maintenance in NDMM to evaluate safety and efficacy of this approach Methods Between 2012 and 2015, 72 patients were enrolled in a phase II trial of the CarBiRD regimen for initial treatment of symptomatic NDMM. Patients received Carfilzomib intravenously over 30 minutes on days 1, 2, 8, 9, 15, 16 of a 28 day cycle with Dex 20mg orally on days of Carfilzomib therapy. Carfilzomib was administered at a dose of 20mg/m2 on days 1 and 2 of cycle one of therapy before escalation to target dosing on all subsequent treatment days. The initial protocol was designed with a target Carfilzomib dosing of 45mg/m2, following the enrollment of the first 26 patients on protocol the dosing was increased to 56mg/m2. After maximum response was achieved with Kd, defined as complete response or stable m-protein for 2 consecutive cycles, patients who were eligible for autologous stem cell transplant underwent stem cell collection. Patients then initiated consolidation with Lenalidomide, clarithromycin and Dex (BiRD). BiRD consisted of Lenalidomide 25mg daily on days 1-21 of 28 day cycles, with clarithromycin 500mg twice daily and Dex 40mg on days 1, 8, 15 and 22. BiRD was also continued until achievement of maximum response and patients subsequently initiated maintenance Lenalidomide (Len) at a dose of 10mg on 21 of 28 day cycles. Results 70 out off 72 patients completed at least one cycle of Kd and were evaluated for response. 15 patients came off trial during Carfilzomib therapy: 7 for toxicity, 2 for progression of disease and 6 for either withdrawal of consent, insurance issues or non-compliance. 3 patients came off trial during BiRD consolidation: 1 each for toxicity, progression of disease and withdrawal of consent. The remaining 57 patients initiated BiRD and 54 Len maintenance respectively. Responses are summarized in table 1. The overall response rate was 94% with 84% of patient's achieving a VGPR or better and 37% achieving CR or stringent CR. The rate of CR/sCR increased from 13% (9 of 70 patients) with Kd induction to 28% (16 of 57) with BiRD consolidation and 48% (26 of 54) with Len maintenance. 30% of patients (17 of 57) experience an increased depth of response by at least 1 IMWG response category during BiRD consolidation from their maximum response to Kd. 19% (10 of 54) had an increased depth of response category during Len maintenance. The large majority of adverse events were grade 1 or 2. The most common toxicities across protocol were low-grade gastrointestinal events. The most common grade 3 or higher toxicities were infectious with 17% of patients (12 of 72) experiencing at least one grade 3 or higher infection. Peripheral neuropathy developed in 31% of patients with no grade 3 or higher neuropathy emerging during treatment. The rate of emergent hematologic toxicities was very low across protocol. Discussion CarBiRD is an effective and well-tolerated treatment regimen for patients with NDMM. Using a sequential treatment approach with a highly effective PI and IMiD as the back bones of successive therapies led to high rates of overall response, VGPR or better and complete response in a deferred transplant and transplant ineligible setting. Disclosures Rossi: Takeda: Speakers Bureau; Onyx: Research Funding, Speakers Bureau; Janssen: Speakers Bureau; Celgene: Consultancy, Speakers Bureau. Perry:Celgene: Speakers Bureau. Pekle:Millenium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Coleman:Immunomedies: Equity Ownership, Other: Leadership; AbbVie: Equity Ownership; Gilead: Consultancy, Research Funding, Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau; Pharmacyclics, LLC, an AbbVie Company: Research Funding, Speakers Bureau; Pfizer: Research Funding; GSK: Research Funding; Karyoharm: Research Funding. Allan:Pharmacyclics: Speakers Bureau; Genentech: Speakers Bureau; Abbvie: Speakers Bureau. Niesvizky:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Onyx: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Mark:Onyx: Research Funding, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Description: Introduction: Venetoclax (Ven), an oral BCL2 inhibitor, is approved for the treatment (tx) of relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). Ven is generally well tolerated, and side effects observed in clinical trials have been consistent with other CLL tx. Clinical trials using the approved dose escalation schedule report negligible rates of clinical tumor lysis syndrome (TLS). We aimed to understand rates of select adverse events (AEs) including cytopenias, infections, and TLS in CLL patients (pts) treated with Ven in community and academic settings. To do so, we examined 297 pts with CLL who received Ven, either alone or paired, in this multicenter, international study. Methods: We conducted a retrospective cohort study of Ven treated pts with CLL across at 15 academic (n=169) and 51 community (n=128) centers outside of the clinical trial setting. This study represents a collaboration between US centers, CLL Collaborative Study of Real World Evidence (CORE), and UK CLL Forum. Demographics, baseline disease characteristics, Ven dosing, TLS risk (per FDA Ven label) and prophylaxis, and AEs were collected. Lab vs. clinical TLS was defined by Howard criteria. PFS was estimated by Kaplan Meier methodology. All comparisons were descriptive. Results: Of the 297 pts examined, median age at Ven initiation was 67 (range 37-91). The group was 69% male, 96% had R/R CLL, and 45% had del17p. Baseline characteristics stratified by practice setting are included in Table 1. 80% received Ven as monotherapy while 20% received it paired with another agent (anti-CD20 mAb (75%), ibrutinib (8.5%), other (16.5%)). All pts were treated outside of clinical trials. During dose escalation, 81% achieved a 400 mg dose and 65% maintained 400 mg following escalation (cyp3A4 use unknown). TLS risk was low in 40%, intermediate (int) in 32%, and high risk in 28%. CT scan prior to Ven initiation was performed in 62%. At least one hospitalization occurred for 56% of low, 80% of int, and 88% of high risk pts (63% of the total cohort). Table 1 describes the distribution of TLS risk and frequency of hospitalizations in academic, community centers. TLS prophylactic measures were available for a subset of pts. Allopurinol was used for 91% (n=68/75) of low, 93% (n=52/56) of int, and 94% (n=29/31) of pts at high risk for TLS. Rasburicase was used for 27% (n=28/102) of low, 42% (n=34/81) of int, and 72% (n=57/79) of high risk pts. Normal saline was used in 85% (n=62/73) of low, 88% (n=49/56) of int, and 97% (n=30/31) of high risk pts. TLS occurred in 8.4% of pts (n=25/297). Three lab and 2 clinical events occurred in low risk pts, 7 lab and 3 clinical events in int risk pts, and 7 lab and 3 clinical events in high risk pts. Of pts with TLS, 1 has discontinued Ven. Of pts with clinical TLS, all were hospitalized, received allopurinol and normal saline, and 28% received rasburicase. 72% with TLS had creatinine clearance