Citations

Abstract We evaluated the joint associations between a new 313-variant PRS (PRS313) and questionnaire-based breast cancer risk factors for women of European ancestry, using 72 284 cases and 80 354 controls from the Breast Cancer Association Consortium. Interactions were evaluated using standard logistic regression and a newly developed case-only method for breast cancer risk overall and by estrogen receptor status. After accounting for multiple testing, we did not find evidence that per-standard deviation PRS313 odds ratio differed across strata defined by individual risk factors. Goodness-of-fit tests did not reject the assumption of a multiplicative model between PRS313 and each risk factor. Variation in projected absolute lifetime risk of breast cancer associated with classical risk factors was greater for women with higher genetic risk (PRS313 and family history) and, on average, 17.5% higher in the highest vs lowest deciles of genetic risk. These findings have implications for risk prevention for women at increased risk of breast cancer.

TPS7574 Background: Pts with LBCL who have persistent disease assessed by dynamic PET after rituximab-based induction therapy have an increased risk of death (Casasnovas, et al. Blood. 2017). Axi-cel is an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy approved for the treatment of pts with relapsed/refractory LBCL with ≥ 2 prior systemic therapies. In ZUMA-1, the registrational study of axi-cel in pts with refractory LBCL, the objective response rate (ORR) was 91% (70% complete response [CR] rate) in pts with double-expressor or high-grade LBCL with ongoing responses in 48% after a median follow-up of 27.1 mos (Locke FL, et al. Lancet Oncol 2019). Furthermore, pts with fewer prior lines of therapy and lower tumor burden had higher rates of ongoing responses and manageable safety (Locke et al. ASCO 2018. 3039). ZUMA-12 will investigate the efficacy and safety of axi-cel as a first-line therapy in newly diagnosed pts with high-risk LBCL who have PET-positive disease after 2 cycles of induction therapy. Methods: This Phase 2 study has a planned enrollment of ≈40 pts aged ≥ 18 y with high-risk LBCL, defined by the presence of MYC and BCL2 and/or BCL6 translocations by FISH or an IPI score ≥ 3 any time before enrollment, and an ECOG performance status of 0 – 1. Before enrollment, pts must have a Deauville score of 4 – 5 (Barrington SF et al. J Clin Oncol. 2014) after 2 cycles of chemoimmunotherapy that includes an anti-CD20 monoclonal antibody and anthracycline. After leukapheresis, pts with bulky or rapidly progressing disease may receive optional non-chemotherapy bridging therapy. Following conditioning therapy with cyclophosphamide (500 mg/m2) and fludarabine (30 mg/m2) for 3 days, pts will receive a single infusion of axi-cel at a target dose of 2 × 106 CAR T cells/kg. The primary endpoint is investigator-assessed CR rate per the Lugano classification (Cheson et al. J Clin Oncol. 2014). Key secondary endpoints include ORR, duration of response, event-free survival, progression-free survival, overall response, safety, relapse with CNS disease and levels of blood CAR T cells and serum cytokines over time. Accrual is ongoing. Clinical trial information: NCT03761056.

7520 Background: We report results of a phase 2, open-label study of durvalumab (durva) in combination with R-CHOP or R2-CHOP (R-CHOP + lenalidomide) in previously untreated, high-risk diffuse large B-cell lymphoma (DLBCL). Methods: Subjects (≥18 y; ECOG 0–2) with previously untreated, high/high-intermediate risk DLBCL (IPI ≥3/NCCN-IPI ≥4) were stratified to durva + R-CHOP (Arm A, GCB DLBCL) or R2-CHOP for 6–8 cycles (Arm B, ABC DLBCL) based on cell of origin identified by gene expression followed by durva consolidation up to month 12 from start of induction. After FDA placed clinical holds on trials including combination therapy with checkpoint inhibitors and immunomodulatory agents, the study was revised to include both ABC and GCB in Arm A (durva + R-CHOP). The primary endpoint was complete response rate (CRR) at end of induction; secondary endpoints were rate of subjects continuing to consolidation, safety, and response in biological. Results: A total of 46 subjects were treated (safety; A/B, n=43/3); median age, 62/66 y; male, 61%/67%; ECOG 2, 19%/33%; Ann Arbor stage IV, 79%/33%; bulky disease: 49%/67%; double/triple-hit lymphoma, 30%/33%. As of Aug 2, 2018, 30/3 (A/B) had completed induction therapy, and 19 subjects (A) were ongoing. CRR (95% confidence interval) at end of induction was (A) 54% (37%-71%) and (B) 67% (9%-99%); 68%/67% (A/B) continued to consolidation therapy and were progression free at month 12. Safety profile was as expected for the components of the combination regimen with no new safety signal identified. Frequent treatment-emergent adverse events (TEAEs; ≥25%; A+B) included fatigue (61%), neutropenia (52%), peripheral sensory neuropathy (50%), nausea (46%), diarrhea (28%); constipation, decreased appetite, insomnia, pyrexia (24% each); and alopecia, dizziness, dyspnea, headache, stomatitis (22% each). Grade 3/4 TEAEs occurred in 84%/100% of subjects (A/B), and 3 subjects (2/1) died with no death related to study treatment. Follow-up for efficacy and safety is ongoing. Conclusions: Durva + R-CHOP combination therapy is safe and demonstrates encouraging response rates in subjects with high-risk DLBCL including double-hit lymphoma. Clinical trial information: NCT03003520.

7517 Background: Axi-cel, an anti-CD19 CART cell therapy, achieved 83% ORR, 58% CR rate, with 39% PFS at 2 years in patients (pts) with relapsed refractory large B-cell lymphoma (LBCL) on the ZUMA-1 study (Locke, Lancet Oncology 2018). Data from a 17-center consortium showed response rates were similar in 274 pts treated with commercial axi-cel (Nastoupil, ASH 2018). Here, we performed retrospective analysis of outcomes in pts with progressive disease (PD) after axi-cel. Methods: Response status was determined by Cheson 2014 and reported as date of radiologic relapse. 274 pts were infused by December 26, 2018 with maximum follow-up of 14 months; 116 pts had PD as of Feb 1, 2019. Twelve sites provided additional data, detailing 85% of PD pts (n=99) with a median time to relapse of 54 days (IQR 16-120). Results: Pre axi-cel pt characteristics: median lines of therapy were 4 (range 2-11), 86% were Stage III/IV and 22% were ECOG >1. Following relapse, 60% (n=61) were biopsied and 70% (43/61) had CD19 expression measured. Thirty percent (13/43) were CD19 negative by: IHC (3/13), flow (2/13) or both (8/13). Seventy percent (n=71) received salvage therapy for PD. Median lines of salvage therapy was 1 (range 0-4). The most common therapies were Lenalidomide-based (30%), checkpoint inhibitors (30%), chemotherapy (20%) and radiation (10%). First salvage therapy ORR by regimen: checkpoint inhibitors = 24%, lenalidomide regimens = 20% and chemotherapy = 11%. One patient received allogeneic transplant. Twelve pts enrolled on clinical trial, with one receiving 2nd CAR-T. Median OS following relapse was 108 days (95% LCL 71). Nineteen pts relapsed <3 months after axi-cel and did not receive therapy with median OS 17 days (95% CI 7-49); 33 pts relapsed <3 months and received therapy with 114 day median OS (95% LCL 82). In contrast, 30 pts who relapsed >3 months post axi-cel and received therapy had estimated median OS >220 days (95% LCL 81). Conclusions: Patients with LBCL relapsing less than 3 months following axi-cel have extremely poor outcomes supporting the development of novel therapies. Therapy for relapse >3 months appears promising. JYS and SD contributed equally; APR, DBM and BTH contributed equally.

TPS1136 Background: Hsp90 is a molecular chaperone protein required for the stabilization and activation of many proteins, referred to as Hsp90 ‘clients’, including those commonly implicated in breast tumorigenesis such as HER2, EGFR, ER, PI3K, AKT, P53 and VEGFR. Ganetespib is a novel triazolone inhibitor of Hsp90 being studied in over 20 clinical trials, with over 700 patients treated to date. Ganetespib is ~50x more potent than 1st-generation Hsp90 inhibitors, and has been well tolerated in clinical trials with a favorable safety profile. Mild to moderate, transient diarrhea is the most common adverse event associated with ganetespib infusion and is manageable with appropriate supportive care. Ganetespib has shown activity in preclinical models of HER2+, ER+/PR+ and triple negative breast cancer (TNBC). In a phase I trial, ganetespib demonstrated single-agent clinical activity in HER2+ disease with an objective response rate (ORR) of 15% and a disease stabilization rate of 46% in heavily pretreated patients. This efficacy-screening study is designed to provide further evidence of ganetespib activity and identify potentially predictive biomarkers in metastatic breast cancer. Methods: The ENCHANT-1 trial is an international, first-line Phase II study in two cohorts of breast cancer patients: Cohort A, HER2 amplified (n=35), and Cohort B, TNBC (n=35). HER2+ patients must have received prior anti-HER2 therapy in the adjuvant setting. Patients are treated with ganetespib at 150 mg/m2 twice weekly on a three out of four-week regimen. Primary endpoint: ORR assessed using RECIST1.1 criteria. Key secondary endpoints include metabolic effects as assessed by PET/CT at week 3. Tumor genetic signature and proteomic profiling are performed on patient’s tumors in an effort to develop biomarkers of response. At the time of submission 6 patients have been enrolled into this study. Clinical trial information: NCT01677455.

1055^ Background: Key properties of QoL instruments in a clinical trial setting are reliability, the ability to detect a change, and content validity. Using data from the Study 301 phase III breast cancer trial, we report here content validity and ability to detect a change for the EORTC QLQ-C30 and breast cancer-specific QLQ-BR23 questionnaires. Methods: Patients with locally advanced or metastatic breast cancer were randomized to 21-day cycles of either eribulin mesylate 1.4 mg/m2 given on Days 1 and 8, or capecitabine 1.25 g/m2BID orally on Days 1-14. QoL questionnaires were completed at baseline and at 6 weeks, 3, 6, 12, 18, and 24 months. Objective tumor response was evaluated (complete response [CR]; partial response [PR]; stable disease [SD]; progressive disease [PD]). Univariate and multivariate longitudinal analyses using weighted generalized estimating equations were employed to assess the responsiveness of the QoL scales to objective tumor response. Results: 1,102 patients were randomized (554 eribulin, 548 capecitabine). Global health status (GHS)/QoL scores were low at baseline (55). GHS/QoL scores were highest for patients with CR (70.8), followed by those patients with PR (63.5), SD (60.5), and PD (58.1). Physical functioning followed the same pattern: CR (98.3); PR (79.1); SD (72.8); PD (71.0). Role and social functioning scores were also responsive. Pain increased, while fatigue and body image worsened, with poorer tumor responses. Using the weighted generalized estimating equations, there were improvements in physical (34.78; p<0.01), cognitive (27.29; p<0.01), and social (22.04; p<0.01) functioning, and future perspective 11.47 (p<0.01), in patients who responded (CR and PR) to treatment compared with non-responders. Pain decreased significantly by 28.62 (p<0.01) on a 0-100 scale. Patients who responded also gained appetite and had fewer breast symptoms. Conclusions: These results suggest content validity of the EORTC QLQ-30 and QLQ-BR23 questionnaires as they correlate with changes in objective tumor assessments. Clinical trial information: NCT00337103.

TPS1140^ Background: NKTR-102 is a topoisomerase I inhibitor-polymer conjugate that hydrolyzes to provide continuous exposure to SN-38. A phase 2 trial of single-agent NKTR-102 was conducted in pts with 3rd-line MBC; 2 schedules (q14d; q21d) investigated a dose of 145 mg/m2. ORR was 29% (including 3% CR) with the prior ATC subset demonstrating an ORR of 31%. Dosing q21d was better tolerated; in this arm, median PFS and OS equaled 5.3m and 13.1m, respectively. Trial Design: Pts will be randomized 1:1 to receive single-agent NKTR-102 or TPC in an open-label, randomized, multicenter phase 3 study in pts with advanced breast cancer. Key Entry Criteria: Adult females, with ECOG 0 or 1 with adequate liver, kidney and marrow function. All pts must have received prior therapy with ATC (these drugs can be administered in the neo/adjuvant or locally advanced/metastatic setting). Prior A is not mandated if contraindicated. Prior toxicities must have resolved to ≤ Grade 1 (except sensory neuropathy ≤ Grade 2; complete resolution of prior diarrhea). Pts with brain metastases may be eligible, if lesions are stable for prior 3 weeks without steroids. Methods: Primary efficacy endpoint is OS. Secondary endpoints include: ORR by RECIST v1.1, clinical benefit rate (ORR+SD > 6 months), PFS and QoL. NKTR-102 is given IV at 145 mg/m2 over 90-min every 21 days without premedications. Pts randomized to TPC receive 1 of the following: eribulin, ixabepilone, vinorelbine, gemcitabine, paclitaxel, docetaxel or nab-paclitaxel (the agent must be available at the treating institution). Pts are stratified by region, prior eribulin and receptor status (TNBC, Her2+ or Other). Target Accrual: ~840 pts will be required for sufficient events to occur in the planned follow-up time; OS will be compared using a two-sided log-rank test; 1 interim analysis will occur when 50% of the deaths are reported. PK sampling is performed in a subset of pts. CTCs (isolated by Apocell ApoStream technology) are serially assessed for potential predictive markers of response and toxicity. Enrollment is expected to remain open until late 2013.

1087 Background: EP is a unique topoisomerase 1 inhibitor that provides continuous exposure to SN38. EP demonstrated a 29% overall response rate in patients with mBC, leading to a phase III global BEACON study in patients with mBC. CTCs in patient blood samples provide a minimally invasive approach to detect PD markers of drug activity. We developed quantitative multiplex immunofluorescent assays to measure target-specific PD biomarkers for EP in CTCs isolated pre- and post-treatment. Methods: Assays for Top1, Top2, g-H2Ax, Rad51, ABCG2, and Ki-67 were developed using control (0.1% DMSO) and drug-treated (SN38, 10 uM) tumor cell lines (HCT116, MCF7, A549, SKBr3) and PBMCs from healthy donors. The optimal antibody for each biomarker was then multiplexed in a panel with antibodies against cytokeratin, CD45 and DAPI for phenotypic identification of CTCs. For analysis of BEACON pts, serial 7.5 mL whole blood samples were drawn and shipped ambient to Apocell (Houston, TX) for further processing. PBMCs were separated and CTCs were isolated using ApoStream technology. CTCs were stained for PD markers and analyzed using an iCys laser scanning cytometer equipped with image analysis software. Results: Antibodies bound to tumor cells showed staining confined to the nucleus (Top1, Top2, g-H2AX, Ki-67) or membrane (ABCG2), exhibited defined peak separation from their isotype controls, and signal strength correlated with cellular expression of high and low levels of markers. To date, ~ 80% of BEACON pts consent to participate in the CTC sub-study. As of 30 Oct 2012, data from 167 pre-dose blood samples from BEACON pts were available. 99% of blood samples were successfully processed. 93% had detectable CTCs, yielding a median of 216 CTCs (range: 7.5-14816). Staining was positive for Top1, Top2, g-H2Ax, Rad51, ABCG2, and Ki-67 in 82%, 89%, 16%, 53%, 31%, 52% of samples, respectively. Conclusions: EP target-specific pharmacodynamic biomarkers can be reliably measured in CTCs isolated from patients participating in BEACON. Sample collection and analysis of pre- and post-treatment samples is ongoing. Clinical trial information: NCT01492101.

1050^ Background: In a phase III trial comparing eribulin (E) vs. capecitabine (C) in pts with locally advanced or MBC, a trend for improved OS was observed but a statistically significant superiority was not demonstrated with E vs. C for OS or PFS. The AE profiles were consistent with known side effects. We now report QoL results from this trial. Methods: Pts received eribulin mesylate 1.4 mg/m2 on Days 1 and 8, or C 1.25 g/m2 BID orally on Days 1-14, of a 21-day cycle. Eligible pts had received prior therapy including an anthracycline and taxane, and were receiving study drug as 1st-, 2nd-, or 3rd-line therapy for advanced disease. QoL, a secondary objective, was assessed using EORTC QLQ-C30 and QLQ-BR23 questionnaires at baseline, 6 weeks, 3, 6, 12, 18, and 24 months after starting treatment (or until progressive disease or treatment change), and at unscheduled visits. Longitudinal analyses were carried out using weighted generalized estimating equations adjusted for non-random attrition due to death within 12 months. Model covariates were time (visit), region, and baseline QoL. The primary endpoint was change from baseline for Global Health Status (GHS)/overall QoL; exploratory endpoints were change from baseline for each functional domain, and signs/symptoms. Results: 1,102 pts were randomized (E 554; C 548). GHS/QoL scores were low at baseline for E (56.3) and C (54.7) on a scale of 0 (worse) to 100 (best). GHS/QoL and cognitive functioning improved significantly more in pts receiving E vs. C, (6.5 [p=0.048] and 15.3 [p<0.001], respectively). Emotional functioning improved significantly for pts receiving C vs. E (3.3; p=0.033). Pain was comparable at baseline, and was lower at subsequent visits with both treatments. Patient-reported signs/symptoms in favor of E included nausea and vomiting (E1.9; p=0.043) and diarrhea (-3.7; p=0.001); systemic side effects (5.2; p<0.001) and upset by hair loss (9.3; p=0.023) favored C. Conclusions: GHS/QoL scores improved more in pts receiving E than C. E showed advantages in terms of gastrointestinal effects while C had advantages in relation to hair loss. Clinical trial information: NCT00337103.