Citations

Introduction: Genetic studies of early-onset disease have been an effective strategy to identify novel pathways and drug targets generalizable also to later-onset disease. Few studies have investigated the sex-specific genetic associations with early-onset ischemic stroke even though several features of ischemic stroke differ between males and females. We hypothesized that stratifying the GWAS by sex would reveal novel stroke loci. Methods: We performed a transethnic ischemic stroke GWAS of 3,056 female cases and 4,462 male cases < 60 years-old and 16,192 and 16,048 sex-matched controls, respectively, from the Early Onset Stroke Genetics Consortium. Results: We identified a significant association in women with a locus in close proximity to TMX1 , a transmembrane platelet protein that inhibits platelet function. Additionally, we identified 2 other suggestive (P < 5 x 10 -6 ) loci in females (see Table), i.e., at APOH , which encodes beta2-glycoprotein I, an established GWAS locus for lipoprotein(a), and LRFN2 which has been previously reported to associate with obesity-related measures and type II diabetes. We observed suggestive evidence for association in males with MMP3/MMP12 , a known stroke susceptibility locus. Conclusions: Despite a very modest sample size, sex-specific analyses identified suggestive associations at biologically important novel loci in females and a known stroke locus in males. Further studies of sex-specific associations in both early- and later-onset ischemic stroke are needed.

PURPOSE This guideline updates recommendations of the ASCO guideline on chemotherapy and targeted therapy for patients with human epidermal growth factor receptor 2–negative metastatic breast cancer (MBC) that is either endocrine-pretreated or hormone receptor (HR)–negative. METHODS An Expert Panel conducted a targeted systematic literature review guided by a signals approach to identify new, potentially practice-changing data that might translate into revised guideline recommendations. RESULTS The Expert Panel reviewed abstracts from the literature review and retained 14 articles. RECOMMENDATIONS Patients with triple-negative, programmed cell death ligand-1–positive MBC may be offered the addition of immune checkpoint inhibitor to chemotherapy as first-line therapy. Patients with triple-negative, programmed cell death ligand-1–negative MBC should be offered single-agent chemotherapy rather than combination chemotherapy as first-line treatment, although combination regimens may be offered for life-threatening disease. Patients with triple-negative MBC who have received at least two prior therapies for MBC should be offered treatment with sacituzumab govitecan. Patients with triple-negative MBC with germline BRCA mutations previously treated with chemotherapy may be offered a poly (ADP-ribose) polymerase inhibitor rather than chemotherapy. Patients with HR-positive human epidermal growth factor receptor 2–negative MBC for whom chemotherapy is being considered should be offered single–agent chemotherapy rather than combination chemotherapy, although combination regimens may be offered for highly symptomatic or life-threatening disease. Patients with HR-positive MBC with disease progression on an endocrine agent may be offered treatment with either endocrine therapy with or without targeted therapy or single-agent chemotherapy. Patients with HR-positive MBC with germline BRCA mutations no longer benefiting from endocrine therapy may be offered a poly (ADP-ribose) polymerase inhibitor rather than chemotherapy. No recommendation regarding when a patient's care should be transitioned to hospice or best supportive care alone is possible. Additional information is available at www.asco.org/breast-cancer-guidelines .

Introduction: Genetic studies of early-onset disease have been an effective strategy to identify novel pathways and drug targets relevant to later-onset disease. Few studies have investigated the role of common genetic variation in the etiology of early-onset ischemic stroke (IS). Methods: We performed a GWAS meta-analysis of 38 studies from 10 countries, comprised of 5,847 IS cases of European ancestry under age 60 and 32,533 controls. Results: We identified two genome-wide significant (p< 5 x 10 -8 ) loci (see Figure). The ABO locus has previously been associated with venous thrombosis and ischemic stroke in predominantly older adults, but the effect size of our top SNP (OR 1.18; p = 9.1 x 10 -12 ) is larger than the effect size for this same SNP in MEGASTROKE (OR: 1.05; p = 6.5 x 10 -5 ). The lead SNP at the BCL7A/MLXIP locus is a novel GWAS finding for stroke (OR 1.14, 95% CI 1.08-1.19; p = 1.7 x 10 -8 ) and is noteworthy because of prior reports linking SNPs in these genes to BMI and blood pressure. Conclusions: We identified a novel locus that is near variants associated with BMI and blood pressure. Further studies are needed to confirm this locus, examine subtype specificity, and determine its function. The larger effect size observed at the ABO in this early-onset IS sample compared to older-onset IS samples is consistent with a larger role for prothrombotic mechanisms in early-onset IS.

TPS595 Background: Patients (pts) with HER2+ early breast cancer (EBC) and invasive residual disease (RD) after neoadjuvant therapy (NAT) have a higher risk of relapse than pts with a pathologic complete response (pCR). Post neoadjuvant T-DM1 has improved invasive disease-free survival (iDFS), but pts with estrogen receptor (ER)-negative or nodal RD have suboptimal outcomes and recurrences in the central nervous system are a problem. More effective treatment strategies are needed. The CompassHER2 trials, EA1181 and A011801, leverage pCR to tailor post neoadjuvant therapy in HER2+ EBC. EA1181 is a NAT de-escalation trial of a taxane, trastuzumab and pertuzumab (THP) in clinical stage II-III HER2+ EBC; pts with a pCR complete HP +/- adjuvant radiation (RT) +/- endocrine therapy (ET). A011801 is an escalation trial for pts with high risk HER2+ RD after NAT, examining addition of the HER2 selective tyrosine kinase inhibitor (TKI) tucatinib to adjuvant T-DM1. Methods: Eligibility and Intervention: Pts. with high-risk HER2+ RD (e.g. ER-,node-positive, or both) after a predefined course of neoadjuvant HER2-directed treatment are randomized 1:1 to adjuvant T-DM1+ placebo (pb), vs. T-DM1 and tucatinib with adjuvant RT +/- ET. Eligibility criteria include completion of ≥ 6 cycles of NAT, including ≥ 9 weeks of T and H +/- P. All chemotherapy (CT) must be completed preoperatively unless participating in EA1181 (̃15-30% enrollees); these pts must receive postoperative CT to complete ≥ 6 cycles prior to enrollment on A011801. Pts who received prior HER2-targeted TKIs or antibody-drug conjugates are ineligible. Objectives: The primary objective is to determine if iDFS is higher with addition of T-DM1 to tucatinib in pts with HER2+ EBC with RD after NAT; secondary endpoints include overall survival, breast cancer free survival, distant recurrence-free survival, brain metastases-free survival and disease-free survival. Correlative objectives include the association of i) tumor infiltrating lymphocyte (TILs) levels in the primary tumor and RD with iDFS, ii) TILs with tucatinib benefit, iii) iDFS and circulating tumor cells (CTC) at serial timepoints and iv) the magnitude of benefit of tucatinib (iDFS) in pts with/without detectable pretreatment CTCs. Quality of life and pharmacokinetic endpoints will also be evaluated. Statistics: A011801 is a prospective, double-blind, randomized, phase III superiority trial; stratified by i) receipt of postoperative CT (Y/N), ii) hormone receptor-status (+/-),and iii) pathologic lymph node status (+/-). The study targets an absolute difference of 5% in iDFS (control vs. experimental arm 82% & 87%, HR = 0.7), with a two-sided alpha of 0.05 and power of 80%. The sample size is 981; target accrual = 1031 pts; activation and completion dates are 01/6/21 and ̃ 01/2028. Support: U10CA180821, U10CA180882; Seagen Inc; ClinicalTrials.gov Identifier: NCT04457596 Clinical trial information: NCT04457596.

Abstract Traditional Hardy–Weinberg equilibrium (HWE) tests (the χ2 test and the exact test) have long been used as a metric for evaluating genotype quality, as technical artifacts leading to incorrect genotype calls often can be identified as deviations from HWE. However, in data sets composed of individuals from diverse ancestries, HWE can be violated even without genotyping error, complicating the use of HWE testing to assess genotype data quality. In this manuscript, we present the Robust Unified Test for HWE (RUTH) to test for HWE while accounting for population structure and genotype uncertainty, and to evaluate the impact of population heterogeneity and genotype uncertainty on the standard HWE tests and alternative methods using simulated and real sequence data sets. Our results demonstrate that ignoring population structure or genotype uncertainty in HWE tests can inflate false-positive rates by many orders of magnitude. Our evaluations demonstrate different tradeoffs between false positives and statistical power across the methods, with RUTH consistently among the best across all evaluations. RUTH is implemented as a practical and scalable software tool to rapidly perform HWE tests across millions of markers and hundreds of thousands of individuals while supporting standard VCF/BCF formats. RUTH is publicly available at https://www.github.com/statgen/ruth.

1052 Background: TIG, an agonistic anti-DR5 monoclonal antibody, triggers apoptosis in DR5+ human tumor cells without the aid of crosslinking. TIG has shown strong in vitro and in vivo activity against basal-like breast cancer cells that is enhanced by chemotherapy like paclitaxel. Methods: Randomized 2:1 phase II trial of nab-PAC with/without TIG in TNBC patients. Patients stratified by prior exposure to chemotherapy in the metastatic setting. Patients received nab-PAC weekly x 3 and TIG every other week, every 28 days. Primary endpoint was overall response rate (ORR). Secondary objectives were safety, progression free survival (PFS), TIG immunogenicity, and PK. Biopsies and circulating tumor cells were collected. The trial was not powered to compare arms but allowed early stopping for futility and was sized to estimate ORR with 95% CI. Results: 64 patients enrolled, 60 treated; 39 in the combination arm and 21 in the nab-PAC arm. Of the 39 in the combination arm, there were 2 CR, 9 PR (1 near CR, 96% tumor reduction), 11 SD and 17 PD; ORR 28% (95% CI 14%-42%). Of the 21 in the single agent arm, there were no CR, 8 PR, 4 SD and 9 PD; ORR 38% (95% CI 17%-59%). Higher ORRs were seen in the chemotherapy naïve patients (58% vs. 15% combination and 42% vs. 35% single agent). 2 patients with CR, 1 near CR, and 1 PR in the combination arm are still on therapy (602+, 531+, 466+, 460+ days). PFS was similar in both groups (3.6 months); higher in chemotherapy naïve patients. Combination was well tolerated (most toxicities grade 1/2); the most common AEs were fatigue, alopecia, peripheral sensory neuropathy, anemia, neutropenia, nausea, thrombocytopenia, anorexia, diarrhea, and vomiting. No grade 4 or 5 toxicity. No apparent added toxicity with TIG was seen. Conclusions: Combination therapy with nab-PAC + TIG was well tolerated, without apparent improvement in ORR relative to nab-PAC alone; however, 4 subjects treated as first-line had prolonged clinical benefit with the combination, and correlative studies will investigate markers that might predict clinical outcome (Next-Gen genomic analysis). Clinical trial information: F101004001.

INTRODUCTION: African-Americans (blacks) have higher risk of stroke and coronary heart disease (CHD) - collectively referred to here as cardiovascular disease (CVD), than Caucasian-Americans (whites). Though partly explained by traditional cardiovascular risk factors, half of the excess risk in blacks is not explained by known risk factors. Recent data suggest increased risk of CVD and mortality in individuals with clonal hematopoiesis, which often presents as cytopenia. Using peripheral blood cytopenia as a marker of clonal hematopoiesis, we examined the association between cytopenia and risk of CVD and mortality in blacks and whites. METHODS: The REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort study enrolled 30,239 US black and white adults between 2003 and 2007 (41% black). Socio-demographics and medical history were obtained by telephone interview, and laboratory studies (including complete blood count [CBC]) and physical exam from an in-home visit at baseline. Participants or their proxies were contacted every 6 months to ascertain CVD events, hospitalizations or deaths, and medical records were reviewed to confirm these events. Cytopenia was defined using thresholds in Table 1 as presence of 2 or more of the following: i) hemoglobin in age-, sex-, and race-specific lowest 5th percentile; ii) white cell count in race-specific lowest 5th percentile; iii) platelet count in lowest 5th percentile, and iv) macrocytosis (MCV >98fL). Participants with pre-baseline history of stroke (for analyses including stroke or CVD mortality) or CHD (for analyses including CHD or CVD mortality) and those with missing CBC were excluded. Cox proportional hazards models were used to calculate hazard ratios (HRs) of incident CVD and mortality associated with cytopenia. Models adjusted for socio-demographics (Model 1), Framingham stroke or CHD risk factors (Model 2), and estimated glomerular filtration rate and C-reactive protein (Model 3) were used. Differences in the association of cytopenia with outcomes by race were tested using cross-product interaction terms, using a p of <0.1 for interaction. RESULTS: The study included 19,544 participants who were followed for a median of ~9 years. There were 798 (4.3% of those at risk) incident stroke cases and 727 (4.3%) incident CHD cases; 1033 (5.3%) died of CVD, and 3933 (20.1%) died of all-causes. Cytopenia was present in 378 (1.9%) participants, ranging from 0.9% to 3.5% in blacks, 1.4 to 3.9% in whites, 1.6 to 3.9% in men, and 0.9 to 1.8% in women, with increasing prevalence by age. There was no association between cytopenia and stroke or CHD risk in any model. However, cytopenia was associated with increased risk of all-cause mortality (HR=1.73, 95%CI: 1.34-2.22), and CVD mortality (HR=1.56, 95% CI: 1.11-2.19) in the extended risk factor Model 3 and also in CVD risk factor adjusted model (Model 2), with little evidence of confounding (Table 2). While the race by cytopenia interaction term was not significant in any model for incident CHD or mortality, the interaction for cytopenia by race for stroke was statistically significant (p-interaction=0.08) in Model 2. The HR of stroke for cytopenia in blacks was 0.86 (95%CI: 0.46-1.61), and for whites was 1.96 (95%CI: 1.0-3.82). CONCLUSION: In this large biracial cohort, cytopenia was associated with increased all-cause and CVD mortality. Cytopenia was a race-specific risk factor for stroke affecting white Americans but not black Americans. With growing knowledge on the role of clonal hematopoiesis in CVD risk and mortality, further work is needed to determine if our phenotype of cytopenia is accurate in classifying clonal hematopoiesis and for determining the mortality risk. Given these findings, assessing clonal hematopoiesis and outcomes related to clonal hematopoiesis in diverse populations is critical to understanding the interactions between somatic mutations in hematopoietic cells and CVD/mortality risk. Disclosures Safford: Amgen: Research Funding.

OBJECTIVE Given temporal changes in diabetes prevalence and stroke incidence, this study investigated age, race, and sex differences in the diabetes–stroke association in a contemporary prospective cohort, the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study. RESEARCH DESIGN AND METHODS We included 23,002 non-Hispanic black and white U.S. adults aged ≥45 years without prevalent stroke at baseline (2003–2007). Diabetes was defined as fasting glucose ≥126 mg/dL, random glucose ≥200 mg/dL, or use of glucose-lowering medication. Incident stroke events were expert adjudicated and available through September 2017. RESULTS The prevalence of diabetes was 19.1% at baseline. During follow-up, 1,018 stroke events occurred. Among adults aged &lt;65 years, comparing those with diabetes to those without diabetes, the risk of stroke was increased for white women (hazard ratio [HR] 3.72 [95% CI 2.10–6.57]), black women (HR 1.88 [95% CI 1.22–2.90]), and white men (HR 2.01 [95% CI 1.27–3.27]) but not black men (HR 1.27 [95% CI 0.77–2.10]) after multivariable adjustment. Among those aged ≥65 years, diabetes increased the risk of stroke for white women and black men, but not black women (HR 1.05 [95% CI 0.74–1.48]) or white men (HR 0.86 [95% CI 0.62–1.21]). CONCLUSIONS In this contemporary cohort, the diabetes–stroke association varied by age, race, and sex together, with a more pronounced effect observed among adults aged &lt;65 years. With the recent increase in the burden of diabetes complications at younger ages in the U.S., additional efforts are needed earlier in life for stroke prevention among adults with diabetes.

Selection of antihypertensive treatment according to self-defined ethnicity is recommended by some guidelines but might be better guided by individual genotype rather than ethnicity or race. We compared the extent to which variation in blood pressure response across different ethnicities may be explained by genetic factors: genetically defined ancestry and gene variants at loci known to be associated with blood pressure. We analyzed data from 5 trials in which genotyping had been performed (n=4696) and in which treatment responses to β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blocker, thiazide or thiazide-like diuretic and calcium channel blocker were available. Genetically defined ancestry for proportion of African ancestry was computed using the 1000 genomes population database as a reference. Differences in response to the thiazide diuretic hydrochlorothiazide, the β-blockers atenolol and metoprolol, the angiotensin-converting enzyme inhibitor lisinopril, and the angiotensin receptor blocker candesartan were more closely associated to genetically defined ancestry than self-defined ethnicity in admixed subjects. A relatively small number of gene variants related to loci associated with drug-signaling pathways ( KCNK3, SULT1C3, AMH, PDE3A, PLCE1, PRKAG2 ) with large effect size (−3.5 to +3.5 mm Hg difference in response per allele) and differing allele frequencies in black versus white individuals explained a large proportion of the difference in response to candesartan and hydrochlorothiazide between these groups. These findings suggest that a genomic precision medicine approach can be used to individualize antihypertensive treatment within and across populations without recourse to surrogates of genetic structure such as self-defined ethnicity.