Citations

479 Background: Recent long-term clinical trial follow-up suggests that adding Ox to a fluoropyrimidine (FP) may provide less benefit in adjuvant CC than originally believed (Tournigand JCO 2012). In addition, emerging data on tissue biomarkers such as microsatellite mismatch repair (MMR) and the 12-gene Recurrence Score (RS) suggest these assays may be helpful in better defining treatment benefit, and a new report provides evidence that RS may specifically predict the value of Ox. (O’Connell ASCO 2012) In view of these developments we sought to document current use of adjuvant chemotherapy and physician perceptions about these decisions. Methods: US-based oncologists were recruited to complete a survey and contribute treatment data for their last 3 patients (pts) with stage II disease and last pt with a stage III tumor. Results: 25 gastrointestinal cancer clinical investigators and 77 practicing oncologists participated, providing data from a total of 408 cases (92% treated since 2011). Findings from the 2 groups are similar and are presented in aggregate. A median of 9 and 15 pts annually were evaluated with stage II and III tumors, respectively. Clinicians stated that they require a median of a 5% absolute reduction in relapse rate to use a FP alone and an additional 5% reduction to add Ox. Ox/FP was administered to 95 of 102 pts with stage III tumors (93%) and 85 of 306 pts with stage II disease (28%), particularly to those under age 70 or with T4 tumors (Table). MMR was evaluated in 127 pts (42%) with stage II and 20 pts (20%) with stage III disease. RS was obtained for 46 pts (15%) with stage II tumors, but only 2 pts (2%) with stage III. Conclusions: Adjuvant Ox is employed extensively in spite of the fact that it may provide less benefit than many oncologists report requiring to initiate its use. However, several recent research developments may be laying the groundwork for a change in this treatment practice. [Table: see text]

LBA7008 Background: Treatment options for CLL/ SLL patients (pts) who fail chemoimmunotherapy are limited. We report interim results from a phase III randomized study of ibrutinib (ibr), a first in class covalent BTK inhibitor, vs ofatumumab (ofa) in R/R CLL/SLL. The Data Monitoring Committee recommended this analysis be considered final, based on meeting the primary and a key secondary endpoint. Methods: R/R CLL/SLL pts who failed ≥1 therapy received 420 mg oral ibr daily until progression or IV ofa 300/2000mg for 12 doses. Primary endpoint was progression-free survival (PFS) assessed by an independent review committee (IRC). Secondary endpoints included overall survival (OS), IRC assessed overall response rate (ORR) and safety. Results: Of 391 pts enrolled (median age 67 years; 40% ≥70 years; 57% Rai stage III/IV disease; 30% del 17p), 195 were randomized to ibr and 196 to ofa. Ibr pts had median 3 prior therapies vs 2 for ofa. Median follow-up was 9.4 months (m). Ibr significantly lengthened PFS (median not reached vs 8.1 m; HR 0.215, CI 0.146–0.317, p<0.0001; 78.5% risk reduction), and significantly improved OS (median not reached; HR 0.434, CI 0.238–0.789, p=0.0049) compared with ofa. ORR was 42.6 vs 4.1% (p<0.0001) and ORR+PR with lymphocytosis was 62.6 vs 4.1% for ibr vs ofa. Similar effects were seen in del17p and purine analog refractory subsets. In each arm 2 pts had confirmed Richter’s transformation. Most frequent adverse events (AE) for ibr vs ofa were diarrhea (47.7 vs 17.8%) fatigue (27.7 vs 29.8%), and nausea (26.2 vs 18.3%). Atrial fibrillation was more frequent with ibr (5.1 vs 0.5%). Major hemorrhages were reported in 1.0 vs 1.6% for ibr vs ofa. Drug discontinuation due to AE was 4.1 vs 3.6% for ibr vs ofa. 86% of ibr pts were continuing treatment. 57 pts randomized to ofa with confirmed PD had initiated ibr at cross-over. Conclusions: Compared with ofa, ibr significantly improved PFS, OS and ORR in pts with R/R CLL/SLL. The safety profile was comparable with that previously reported (Byrd NEJM 2013). These results support ibr as a beneficial therapy for R/R CLL patients irrespective of del 17p or purine analog refractory disease. Clinical trial information: NCT01578707.

23 Background: Perineural invasion (PNI) on prostate cancer (PC) biopsies has been associated with disease upgrading among those undergoing radical prostatectomy. However, the clinical significance of PNI in men on active surveillance (AS) has been evaluated by a limited number of studies. Thus, we sought to evaluate the association of PNI with time to clinical and pathological progression in men with PC on AS. Methods: Retrospective analysis of 289 men 48 to 82 years old on AS for low-risk PC (T1c-T2a), Gleason ≤6, ≤3 positive cores, ≤50% of any core involved, prostate-specific antigen (PSA) ≤11ng/ml, life expectancy >5 years and follow-up data in the REduction by Dutasteride of clinical progression Events in Expectant Management study. Progression was divided in pathological (>3 positive cores, >50% core involvement or Gleason >6 in a repeat biopsy) or therapeutic (any treatment for PC) or both. Time to progression was analyzed with Kaplan-Meier plots, log-rank tests and Cox model adjusting for age, PSA density, percent cores involved, maximum core involvement and treatment. Results: A total of 11 (4%) patients had PNI on baseline biopsy. PNI was associated with higher tumor length and maximum core involvement (all P<0.05). PNI was not associated with patient’s age, race, PSA levels or density, percent or number of positive cores. After a median follow-up of 37 months, 125 (43%) patients developed progression. Of these, 95 (76%) patients had pathological and 30 (24%) had therapeutic progression. In univariable analysis, patients with baseline PNI had a shorter time to overall and pathological progression (HR=2.62, 95%CI=1.31-5.23, P=0.006 and HR=2.42, 95%CI=1.03-5.66, P=0.041, respectively). Similar results were obtained in multivariable analysis for overall and pathological progression (HR=2.26, 95%CI=1.10-4.68, P=0.028 and HR=2.13, 95%CI=0.88-5.13, P=0.092, respectively). Conclusions: Among patients with PC on AS, PNI is independently associated with shorter time to progression. Thus, PNI may be used to help select patients for AS and stratify them according to the risk of disease progression.

569 Background: BBI-608 is an oral first-in-class cancer stemness inhibitor that blocks STAT3-mediated transcription of cancer stemness genes. Potent anti-CSC activity was observed in vitro and in vivo,in mono and combination therapy. In phase I studies, BBI-608 was generally well tolerated with encouraging signs of anti-tumor activity. Methods: A phase Ib open label, multi-center study in pts with advanced CRC was undertaken to confirm the RP2D of BBI-608 in combination with FOLFIRI with or without BEV. BBI-608 was administered at 240 mg BID in combination with FOLFIRI (5-FU 400 mg/m2 bolus with 2400 mg/m2, irinotecan 180 mg/m2, and leucovorin 400 mg/m2infusion) with or without BEV 5 mg/kg, administered bi-weekly until progression of disease, unacceptable toxicity, or other discontinuation criterion was met. Results: 18 heavily pretreated pts with an average of > 3 prior lines of therapy of which 10 pts (56%) previously progressed on FOLFIRI were enrolled. Of the 17 pts evaluable for response, 8 pts received FOLFIRI and 9 pts received FOLFIRI with BEV in combination with BBI-608. Most common adverse events included grade 1 and 2 diarrhea, abdominal pain, nausea, vomiting and anorexia. No dose limiting toxicity or new adverse events were seen, and the safety profile was similar to that of each regimen as monotherapy. Grade 3 events related to protocol therapy included diarrhea occurring in 3 pts, fatigue in 2 pts and dehydration in 1 pt. All events resolved after dose reduction and/or start of anti-diarrheal medications. No significant pharmacokinetic interactions were observed. Disease control (PR+SD) was observed in 16 of 17 evaluable pts (94%) with 2 PR (per RECIST 1.1 criteria: 44% and 33% regression) and 14 SD (of which 13 (93%) had tumor regression < 25%). In the evaluable pts, median progression free survival was 5.54 months. Of 17 pts, 7 (41%) had prolonged SD of > 6 months. Conclusions: This phase Ib study confirmed that BBI-608 at 240 mg bid can be safely combined with FOLFIRI with and without BEV, and shows encouraging anti-tumor activity in heavily pretreated CRC pts, even in pts with prior progression on FOLFIRI-based therapy. Clinical trial information: NCT02024607.

LBA3 Background: Irinotecan/5-FU/leucovorin (FOLFIRI) or oxaliplatin/5-FU/leucovorin (mFOLFOX6), combined with bevacizumab (BV) or cetuximab (CET), are first-line treatments for metastatic adenocarcinoma of the colon or rectum (MCRC). The optimal antibody combination is unknown. Methods: Patients (pts) with KRAS wild-type (wt)(codons 12 and 13) MCRC and performance status 0-1 received FOLFIRI or mFOLFOX6 (MD/pt choice at enrollment) and randomized to either CET 400 mg/m2 X 1, then 250 mg/m2 qw or BV 5 mg/kg q2w. The original study included unselected MCRC pts receiving FOLFIRI or mFOLFOX6 and randomized to CET, BV, or both. After 1,420 pts accrued the study amended as follows: only pts with KRAS wt tumors (codon 12 and 13) were included and the combination CET + BV arm was deleted. Rx continued until progression, death, unacceptable toxicity, curative surgery; treatment holidays of 4 wks permitted. Subsequent Rx not mandated. Accrual goal was 1,142 pts. One° endpoint was overall survival (OS). Results: Between November 2005 and March 2012, 3,058 unselected pts enrolled, 2,334 KRAS wt pts randomized; final N =1137 (333 pre-amend eligible retrospective KRAS test, 804 post-amend), median f/u = 24 mos; Median age – 59 y; 61% male. Chemo/BV – 559; chemo/CET – 578. FOLFIRI = 26.6%, mFOLFOX6 = 73.4%. OS analysis planned at 849 events; efficacy futility boundary crossed at 10th interim analysis on 1/29/14. OS - chemo/BV v. chemo/CET = 29.04 (25.66 - 31.21) v. 29.93 (27.56 - 31.21) mos; HR = 0.92 (0.78, 1.09) (p value = 0.34). PFS (by investigator): chemo/BV v. chemo/CET: 10.84 (9.86 - 11.4) v. 10.45 (9.66 - 11.33) mos. There were 94 pts free of disease following surgery, median f/u 40 mos (range 8.0 - 86.0). Outcomes similar by gender. On-study toxicity and deaths as expected. Analyses underway: Expanded RAS, FOLFOX v. FOLFIRI, subsequent therapies, long-term survivors, correlates. Conclusions: Chemo/CET and chemo/BV equivalent in OS in pts KRAS wt (codons 12 + 13) MCRC; either is appropriate in first line. Overall OS of 29 + mos and 8% long-term survivors confirms progress in MCRC. The preference for FOLFOX limits chemotherapy comparison. Expanded RAS and other molecular and clinical analyses may identify subsets of pts who get more or less benefit from specific regimens. Clinical trial information: NCT00265850.

261 Background: Mapatumumab is a fully human agonist monoclonal antibody to the tumor necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1). Sorafenib targets Mcl-1, a key TRAIL resistance protein, and accordingly could enhance mapatumumab's pro-apoptotic activity. Based on this and on preclinical data on mapatumumab in HCC cell lines, the current dose-escalation study is evaluating mapatumumab in combination with sorafenib in patients with advanced HCC. Methods: Eligible patients had advanced HCC, Child-Pugh A or Model for End-Stage Liver Disease score < 15, and were positive for hepatitis B surface antigen or hepatitis C antibody. Intravenous mapatumumab was administered at 3, 10 or 30 mg/kg every 21 days with sorafenib (400 mg twice daily) until disease progression or unacceptable toxicity. Dose-limiting toxicities (DLTs) included events considered at least possibly related to mapatumumab and/or its interaction with sorafenib. Tumor measurements were performed every 2 cycles. Dose escalation required at least 3 patients in a cohort to receive >= 50% of full-dose sorafenib in the first 2 cycles. Results: To date, 19 patients have been enrolled in the 3 mg/kg (n=6), 10 mg/kg (n=9) and 30 mg/kg (n=4) cohorts and have received a median of 4 cycles (range 1 to 24 cycles); 4 patients have received >= 11 cycles. The maximum tolerated dose has not been reached. DLTs that prompted expansion of the 3 mg/kg and 10 mg/kg cohorts were elevations of amylase and/or lipase (1 at 3 mg/kg, 1 at 10 mg/kg). Other Grade 3-4 events considered at least possibly related to mapatumumab and/or its interaction with sorafenib included hepatic pain (1/17), thrombocytopenia (1/17), increased aspartate aminotransferase (1/17), increased lipase (1/17), and increased gamma-glutamyltransferase (1/17). Two patients have had a partial response and 4 patients have had stable disease lasting > 12 weeks, based on investigator assessment. Conclusions: Mapatumumab was well-tolerated at doses up to 30 mg/kg in combination with sorafenib in patients with HCC and viral hepatitis. A randomized phase II study of this combination in patients with advanced HCC is planned. [Table: see text]

ObjectiveTo determine the sensitivity and specificity of ocular and cervical vestibular evoked myogenic potentials (VEMPs) in the diagnosis of superior semicircular canal dehiscence (SCD) and to describe the VEMP response characteristics that are most sensitive to SCD and compare the findings to previous reports.Study DesignCase series with chart review.SettingTwo tertiary neurotologic referral centers.Subjects and MethodsCervical and ocular VEMP peak‐to‐peak amplitudes and thresholds from 39 adult patients older than 18 years with surgically confirmed SCD were compared with 84 age‐matched controls.ResultsUsing receiver operating characteristic (ROC) curves, cervical VEMP (cVEMP) amplitudes, cVEMP thresholds, and ocular VEMP (oVEMP) amplitudes had areas under the curve of 0.731, 0.912, and 0.856, respectively, all of which were statistically significant (P <. 0001). For cVEMP thresholds, at the clinical equivalent ≤85‐dB normalized hearing level (nHL) threshold, the sensitivity and specificity were 97.3% and 31.3%, respectively. At the ≤70‐dB nHL threshold, the sensitivity and specificity were 73.0% and 94.0%, respectively. For oVEMP amplitudes >12.0 µV, the sensitivity and specificity were 78.6% and 81.7%, respectively.ConclusionData from this multicenter study suggest that both cVEMP thresholds and oVEMP amplitudes remain good diagnostic tests for identifying SCD, with each test dependent on a number of factors. The sensitivity and specificity of these individual tests may vary slightly between centers depending on testing parameters used.

Abstract Introduction Genetic loci for Alzheimer's disease (AD) have been identified in whites of European ancestry, but the genetic architecture of AD among other populations is less understood. Methods We conducted a transethnic genome‐wide association study (GWAS) for late‐onset AD in Stage 1 sample including whites of European Ancestry, African‐Americans, Japanese, and Israeli‐Arabs assembled by the Alzheimer's Disease Genetics Consortium. Suggestive results from Stage 1 from novel loci were followed up using summarized results in the International Genomics Alzheimer's Project GWAS dataset. Results Genome‐wide significant (GWS) associations in single‐nucleotide polymorphism (SNP)–based tests ( P < 5 × 10 −8 ) were identified for SNPs in PFDN1/HBEGF , USP6NL/ECHDC3 , and BZRAP1‐AS1 and for the interaction of the (apolipoprotein E) APOE ε4 allele with NFIC SNP. We also obtained GWS evidence ( P < 2.7 × 10 −6 ) for gene‐based association in the total sample with a novel locus, TPBG ( P = 1.8 × 10 −6 ). Discussion Our findings highlight the value of transethnic studies for identifying novel AD susceptibility loci.