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By sequencing autozygous human populations, we identified a healthy adult woman with lifelong complete knockout of HAO1 (expected ~1 in 30 million outbred people). HAO1 (glycolate oxidase) silencing is the mechanism of lumasiran, an investigational RNA interference therapeutic for primary hyperoxaluria type 1. Her plasma glycolate levels were 12 times, and urinary glycolate 6 times, the upper limit of normal observed in healthy reference individuals (n = 67). Plasma metabolomics and lipidomics (1871 biochemicals) revealed 18 markedly elevated biochemicals (>5 sd outliers versus n = 25 controls) suggesting additional HAO1 effects. Comparison with lumasiran preclinical and clinical trial data suggested she has <2% residual glycolate oxidase activity. Cell line p.Leu333SerfsTer4 expression showed markedly reduced HAO1 protein levels and cellular protein mis-localisation. In this woman, lifelong HAO1 knockout is safe and without clinical phenotype, de-risking a therapeutic approach and informing therapeutic mechanisms. Unlocking evidence from the diversity of human genetic variation can facilitate drug development.

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 369 nominally genome-wide significant loci ( P < 5 × 10 −8 ) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 360 loci for which replication data were available, 241 loci influencing surface area and 66 influencing thickness remained significant after replication, with 237 loci passing multiple testing correction ( P < 8.3 × 10 −10 ; 187 influencing surface area and 50 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation ( r G = −0.32, SE = 0.05, P = 6.5 × 10 −12 ), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 46 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function. Identifying genetic influences on human cortical structure. ( A ) Measurement of cortical surface area and thickness from MRI. ( B ) Genomic locations of common genetic variants that influence global and regional cortical structure. ( C ) Our results support the radial unit hypothesis that the expansion of cortical surface area is driven by proliferating neural progenitor cells. ( D ) Cortical surface area shows genetic correlation with psychiatric and cognitive traits. Error bars indicate SE. IMAGE CREDITS: (A) K. COURTNEY; (C) M. R. GLASS

e17538 Background: Adherence to guideline-consistent chemotherapy-induced nausea and vomiting (CINV) prophylaxis is suboptimal. The primary aim of this study was to evaluate the magnitude of compliance to institutional guideline-directed antiemetic prophylaxis using a computerized physician order entry system at a single tertiary care institution. A nurse survey was also performed to evaluate how oncology practices, within a cooperative group, manage clinician orders for the prevention of CINV. Methods: The electronic medical records of 100 consecutive patients were evaluated. The primary endpoint was the incidence of compliance to provide all aspects of institutional guideline-directed antiemetic prophylaxis for acute (Day 1) and delayed (Days 2-4) CINV for patients receiving high, moderate, low, and minimally-emetogenic chemotherapy (HEC/MEC/LEC/MinEC). Noncompliance was declared if a recommended antiemetic was not prescribed per the guidelines or if additional antiemetics were prescribed. Descriptive analyses were performed on the convenience sample. Logistic regression was applied to determine the association of potential factors with noncompliance. Results: The incidence of compliance on Days 1-4 was 94%. Half of the noncompliant events occurred on Day 1 alone and involved the omission of pre-chemotherapy prochlorperazine in patients receiving LEC (3 of 6, 50%). There was a high-degree of compliance to institutional guidelines for delayed CINV (97%). Patients receiving doxorubicin/cyclophosphamide were numerically less likely to receive institutional guideline-directed antiemetic prophylaxis, compared to patients receiving other chemotherapy regimens (OR: 0.24 (0.04, 1.36), p-value: 0.05). No other factors were significantly predictive for compliance. The nurse survey demonstrated significant variability amongst the involved institutions, with regards to antiemetic prescribing practices. Conclusions: Computerized physician order entry is associated with impressive adherence to clinician prescribing practices, according to institutional guideline-directed antiemetic prophylaxis, for preventing acute and delayed CINV.

6587 Background: Recently the Patient-Reported Outcomes version of the CTCAE was developed to augment clinically graded adverse events with information reported directly by patients on clinical trials (Basch, 2009). The validation and potential application of PRO-CTCAE in phase I clinical trials are of great interest as toxicity is the primary endpoint. Methods: Selected PRO-CTCAE items (21 items measuring 12 symptomatic adverse events) corresponding to the major adverse events required to be graded clinically were collected in an ongoing phase I clinical trial of weekly cilengitide and paclitaxel in patients with advanced solid malignancies (NCT01276496). PRO-CTCAE was administered in a paper booklet by a clinical research associate prior to treatment on days 1, 8 and 15 of their regular visits. These PRO-CTCAE items were summarized descriptively in comparison to clinician-assessed CTCAE ver 4.0 (NCI, 2009) during the first cycle. As a pilot study to assess feasibility of PRO-CTCAE in phase I trials, PRO-CTCAE was not intended for determination of dose-limiting toxicity. Results: Twelve patients were accrued to two separate doses of cilengitide and paclitaxel. The median age was 56 (range 36—67) and half of patients were female. All patients had an ECOG performance score <= 1. Over 90% of patients had received prior surgery and chemotherapy. All but one patient completed weekly PRO-CTCAE during the first cycle, the only patient refused to complete weeks 2 and 3 did not give a reason. PRO-CTCAE captured most of the symptomatic adverse events reflected in clinician-assessed CTCAE. Some symptomatic adverse events were not reported clinically by CTCAE but were reported by patients by PRO-CTCAE. Overall, PRO-CTCAE items indicated slightly more severe degree of symptoms experienced by patients than those reported in CTCAE. Conclusions: This is the first study that PRO-CTCAE items were integrated within regular study visits in a phase I trial. The administration of PRO-CTCAE has been proved feasible and fruitful, providing consistent and enhanced symptomatic toxicity from the patient point of view. The addition of PRO-CTCAE did not significantly increase patient burden. Clinical trial information: NCT01276496.

4032 Background: PNET has long had few effective therapies other than chemotherapy. Placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co primary endpoints were RR and 6-month PFS. Planned enrollment was 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: 55 pts were eligible for response assessment. Confirmed PR was documented in 20 of 55 patients (37%). 44 of 55 (80%) patients were progression-free at 6 months. Of 49 pts evaluable for this endpoint, 12 month PFS is 49%. 15 patients remain on therapy. For evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (18%), hyperglycemia (13%), fatigue (11%). leukopenia (9%), headache (9%), proteinuria (7%), and hypokalemia (7%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 37%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 80% in a population of patients with RECIST criteria progression within 7 months of study entry. Phase III trials of combined VEGF/mTOR inhibition in PNET should be pursued. Clinical trial information: NCT01010126.

3501 Background: Cumulative neurotoxicity commonly leads to early discontinuation of oxaliplatin-based therapy. In a relatively small, prematurely-discontinued, randomized study, IV CaMg was associated with reduced oxaliplatin-induced sNT (Grothey, JCO, 2011). N08CB was designed to definitively test whether IV CaMg significantly decreases cumulative oxaliplatin-related sNT. Methods: 353 pts with colon cancer undergoing adjuvant therapy with FOLFOX were randomized to 3 arms: IV CaMg (1g calcium gluconate, 1g magnesium sulfate) before and after oxaliplatin vs PL before and after vs CaMg before and PL after. The primary endpoint was cumulative sNT repeatedly measured by the sensory subscale of the EORTC QLQ-CIPN20. Secondary endpoints, using CTCAE 4.0 and an oxaliplatin specific neurotoxicity scale, were also assessed. Acute neuropathy data were also collected for 5 days following each oxaliplatin dose. The area under the curve (AUC) of the sensory subscale during the treatment cycles was used as summary measures for comparison. The Wilcoxon rank-sum tests were conducted for each treatment versus placebo arm, at 2.5%, adjusting for multiplicity using Bonferroni’s approach. Results: CaMg did not reduce cumulative sNT. Primary and secondary analyses data are summarized in the Table. In addition, there were no significant differences between arms regarding oxaliplatin administered doses or chemotherapy discontinuation rates. Also, there were no substantial differences in acute neuropathy scores or side-effects between study arms. Conclusions: This study does not demonstrate any activity of IV CaMg as a neuroprotectant against oxaliplatin-induced neurotoxicity. Clinical trial information: NCT01099449. [Table: see text]

TPS1608 Background: Metformin may have growth inhibitory effects on many cancer types including breast cancer. NCIC MA.32 is a randomized placebo-controlled trial examining the effects of 5 years of metformin in women with breast cancer ( http://clinicaltrials.gov/show/NCT01101438 ). This trial offers us the opportunity to explore the effects of metformin on breast cancer biomarkers to gain an understanding of the potential chemo preventive effects of this drug. The primary aim of this companion to MA.32 (Alliance trial # A211201) is to examine the effects of 1 year of metformin vs placebo on breast density for women with Estrogen Receptor negative (ER-) breast cancer. Secondary aims of this study include: evaluation of breast density following 2 years of metformin use, and correlation of density with fasting insulin, glucose and Homeostasis Model Assessment (HOMA). Exploratory aims include examination of the effects of metformin on second cancer rates. Methods: Eligible women must have been enrolled on MA.32 (North America accrual completed January 23, 2013), have hormone receptor-negative breast cancer, and breast composition on mammography >25% glandular density, have a digital mammogram within 12 months of registration on MA.32 and have an intact, unaffected contralateral breast. Women enrolled on this study must provide menstrual cycle data (if premenopausal) and digital mammograms. All other study related information is gathered through participation in MA.32. Mammographic density will be calculated using Cumulus software (the Boyd method). Our accrual goal is 458 patients (229 per arm) and with an assumption of 20% drop out due to drug intolerance and another 20% due to ineligibility. Therefore, with a sample size of 274 (137 per arm) we will have at least 85% power to detect a 4% difference between study arms, i.e., 5% change from baseline to one year of treatment for metformin vs. 1% for placebo, using the two-sided two-sample t-test at a significance level of 5%. This study was activated in the United States on 8/22/2012 and 15 patients have been accrued to date. This study is sponsored by the NCI and the Alliance for clinical trials. Clinical trial information: NCT01666171.

10003 Background: Preclinical studies demonstrate synergistic anti-tumor activity by inhibiting mTOR and IGF-1R. This study evaluated the safety and efficacy of A12 and TEM in 3 chemo-refractory cohorts: IGF-1R (+) STS (Arm A), IGF-1R (+) bone (Arm B), and IGF-1R (-) bone and STS (Arm C). Methods: An optimal Simon 2 stage design was used for each arm. The primary end-point was progression free survival (PFS) at 12 weeks. Based on historical data, a 40% PFS rate was considered promising and a 20% PFS non-promising (type I/ II error, 0.05/0.10). ≥5 PFSs at 12 weeks were required in the first 19 and ≥16 PFSs were required in a total of 54 pts to consider each arm positive. Key eligibility: measurable disease (RECIST 1.1), age ≥18, 1- 4 priors, ECOG status 0-1. A12 (6 mg/kg) and TEM (25 mg) were administered IV weekly. Pre and post treatment tumor biopsies and plasma for IGF-1 and IGFBP3 were obtained. 20 Sarcoma Centers participated. Results: Starting in 02/2010, 383 pts were tested for IGF-1R by immunohistochemistry (IHC; 54% +) and 171 were treated: mean age 47 (range: 18-80), mean # priors 2.2 (range: 1-4). Grade 3/4 toxicities ≥10%: lymphopenia (12%), mucositis (10%). By intent to treat (ITT) analysis, each arm of the study achieved its primary 12 week PFS end-point (≥16 PFSs): Arm A: 18/56 (32%), Arm B: 19/50 (38%) (4 too early), Arm C: 27/63 (43%). The one-sided 95% CI for 12-week PFS is (0.22, 1), (0.27, 1), and (0.32, 1), respectively. By ITT the median PFS (95% CI) in weeks for each arm is 6.3 (5.9, 12.0), 11.0 (8.0, 18.0) and 11.6 (9.0, 17.9), respectively, and for chondro (n=18), Ewing’s (n=24), and osteo (n=23) only it is 22.6 (5.7, 40.9), 10.4 (5.7, 17.9) and 6.0 (6.0, 18.0), respectively. Westerns on 32 matched pair tumor biopsies indicate inhibition of IGF-1R, pAKT and pS6. Of biopsies on 7 IGF-1R (-) IHC pts (Arm C), 5 were IGF-1R (+) by western. Plasma biomarkers did not correlate with PFS. Conclusions: A12 and TEM met its primary end-point of improved PFS in pts with metastatic sarcoma. This effect was independent of IGF-1R status by IHC. These results support further clinical development of this combination in bone and STS.

4047 Background: PNET has long had few effective therapies other than chemotherapy. Recent placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/ PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co-primary endpoints were RR and 6-month PFS. Planned enrollment is 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: Confirmed PR was documented in 13 of the first 25 (52%) evaluable patients. 21 of 25 (84%) patients were progression-free at 6 months. Both endpoints exceeded the protocol-defined criteria to continue enrollment. For 36 evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (14%), leukopenia (11%), lymphopenia (11%), hyperglycemia (11%), mucositis (8%), hypokalemia (8%), and fatigue (8%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 52%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 84% in a population of patients with RECIST criteria progression within 7 months of study entry. Accrual is ongoing.