A randomized double-blind phase II study of the Seneca Valley virus (NTX-010) versus placebo for patients with extensive stage SCLC (ES-SCLC) who were stable or responding after at least four cycles of platinum-based chemotherapy: Alliance (NCCTG) N0923 st
7509 Background: NTX-010 is a naturally occurring replication-competent picornavirus with potent and selective tropism for SCLC tumor cells expressing neuroendocrine markers. A phase I study of NTX-010 showed evidence of antitumor activity in patients with SCLC. Methods: ES-SCLC patients (pts) with SD, PR or CR after at least 4 cycles of platinum-based chemotherapy were pre-registered to confirm diagnosis of SCLC with > 1 neuroendocrine marker by a central pathology review. Eligible pts were.randomized 1:1 to placebo (B) or NTX-010 (A). NTX-010 or placebo was administered intravenously as a 1-hour infusion in 100 mL normal saline as a single dose of 1 x1011vp/kg. Viral studies to determine distribution, clearance of the virus and the presence of neutralizing antibodies were done. The primary goal of this trial was to compare the progression-free survival (PFS) of arm A to B based on a sample size of 45 patients per arm to detect an improvement in median PFS from 3 to 5 months (m). A pre-planned interim futility analysis was done after 40 PFS events, and reported here. Results: The trial is permanently closed to accrual. One-hundred and twenty pts were pre-registered, of whom 58 were randomized. Baseline age, gender, ECOG performance status, and histology were balanced between arms. Median age was 63 (range: 44 - 82). 31% of pts had a PS of 0 and 69% of 1. Grade 4 adverse events were seen in 3 (12.5%) patients in arm A and none in arm B. Based on the interim futility analysis, PFS was 1.7 m (95% CI: 1.3-3.1) for arm A and 1.7 m (95% CI: 1.4-4.3) for arm B. Pts with viral RNA at 7 (7 pts) and 14 (6 pts) days had worse PFS compared to those with no detectable levels within arm A (1.0 vs 1.6 m, p=0.02; 0.9 vs. 1.2 m, p=0.06). Median follow-up in pts is 6.1 m. The 3-month OS estimates are 83% (95% CI: 69%-100%) and 85% (70%-100%) for arms A and B respectively. Conclusions: This phase II study showed no benefit in PFS for ES-SCLC patients receiving NTX-010. Pts with detectable virus at 7 and 14 days had worse PFS. Clinical trial information: NCT01017601.
A Randomized Phase IIb Trial of
myo
-Inositol in Smokers with Bronchial Dysplasia
Abstract Background: In patients with Barrett's esophagus, chronic reflux injury and inflammation are associated with esophageal adenocarcinoma, one of the most rapidly increasing lethal cancers. Epidemiological and preclinical studies support decreased risk of esophageal adenocarcinoma with NSAID use. Gastroesophageal refluxate contents can promote carcinogenesis in Barrett's metaplasia by activating AKT, which up regulates COX-2 expression and prostaglandin biosynthesis. We recently noted that neoplastic transformation in Barrett's esophagus is associated with increased AKT expression, particularly isoform AKT1. The AIM of this study is to investigate the effect of NSAID (Aspirin) use in patients with Barrett's esophagus on AKT1 expression using frozen tissue from the randomized, phase II trial of aspirin and esomeprazole for esophageal cancer chemoprevention in Barrett's esophagus patients and to assess the functional consequences of AKT1 expression in-vitro. Methods and Results: In a subset of patients (12 of 120 patients) with Barrett's esophagus who were randomized to placebo, lower dose (81 mg) or higher dose (325 mg) Aspirin for 4 weeks, both PCR and Western blot revealed marked reduction in AKT1 expression in patients who received 325 mg of Aspirin daily compared to patients who received placebo. Our in-vitro experiments support that AKT1 expression is functionally relevant to the process of carcinogenesis in Barrett's epithelial cells. Using adenovirus to induce AKT1 expression, we show that increased AKT1 expression increases Barrett's epithelial cell growth, facilitates RAS-mediated transformation of pre-neoplastic epithelial cells and promotes colony formation. Since AKT1 is known as Warburg kinase and regulates cellular glucose uptake to support aerobic glycolysis during growth de-regulation and neoplasia, we examined the uptake of fluorescent deoxyglucose analog (2-NBDG) in Barrett's epithelial cells transduced with AKT1 adenovirus. At 48 hrs, compared to control, AKT1 overexpression resulted in increased glucose uptake both by metaplastic and neoplastic Barrett's epithelial cells. Transcriptional repression of AKT1 abrogated the 2-NBDG uptake by these cells. Finally, we did pathway specific qPCRs and noted that use of Aspirin is associated with altered expression of chromatin remodelers that could down-regulate AKT1 expression. Conclusion: Collectively, our results demonstrate that Aspirin mediated down-regulation of Warburg kinase AKT1 in patients with Barrett?s esophagus is a novel mechanism for the regulation of Barrett?s epithelial cell growth. The in-depth characterization of molecular mechanisms is currently underway. This abstract is also presented as Poster A82. Citation Format: Navtej S. Buttar, Gary W. Falk, Cathrine J. DeMars, Sonia Chowdhury, Ahmed Elebiary, Anamay Sharma, Sidhartha Chaudhry, Nathan R. Foster, Katie L. Allen Ziegler, Yvonne Romero, Norman E. Marcon, Thomas Schnell, Douglas A. Corley, Prateek Sharma, Marcia R. Cruz-Correa, Chin Hur, David E. Fleischer, Amitabh Chak, Kenneth R. DeVault, David S. Weinberg, Gary Della’Zanna, Ellen Richmond, Thomas C. Smyrk, Sumithra Mandrekar, Paul J. Limburg. Aspirin mediated downregulation of Warburg kinase AKT1 in patients with Barrett's esophagus: Implications in neoplastic transformation. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr PR-03.
Population Pharmacokinetic Model for Cancer Chemoprevention With Sulindac in Healthy Subjects
AbstractSulindac is a prescription‐based non‐steroidal anti‐inflammatory drug (NSAID) that continues to be actively investigated as a candidate cancer chemoprevention agent. To further current understanding of sulindac bioavailability, metabolism, and disposition, we developed a population pharmacokinetic model for the parent compound and its active metabolites, sulindac sulfide, and exisulind. This analysis was based on data from 24 healthy subjects who participated in a bioequivalence study comparing two formulations of sulindac. The complex disposition of sulindac and its metabolites was described by a seven‐compartment model featuring enterohepatic recirculation and is the first reported population pharmacokinetic model for sulindac. The derived model was used to explore effects of clinical variables on sulindac pharmacokinetics and revealed that body weight, creatinine clearance, and gender were significantly correlated with pharmacokinetic parameters. Moreover, the model quantifies the relative bioavailability of the sulindac formulations and illustrates the utility of population pharmacokinetics in bioequivalence assessment. This novel population pharmacokinetic model provides new insights regarding the factors that may affect the pharmacokinetics of sulindac and the exisulind and sulindac sulfide metabolites in generally healthy subjects, which have implications for future chemoprevention trial design for this widely available agent.
Phase 0 Clinical Chemoprevention Trial of the Akt Inhibitor SR13668
Purpose To evaluate the efficacy and toxicity of pemetrexed combined with bevacizumab as second-line therapy for patients with advanced non–small-cell lung cancer (NSCLC) and to correlate allelic variants in pemetrexed-metabolizing genes with clinical outcome. Patients and Methods Patients with previously treated NSCLC received pemetrexed (500 mg/m2 intravenous) combined with bevacizumab (15 mg/kg intravenous) every 3 weeks. The primary end point, evaluated using a one-stage Fleming design for detecting a true success rate of at least 70%, was the proportion of patients who were progression free and on treatment at 3 months. Polymorphisms in genes responsible for pemetrexed transport (reduced folate carrier [SLC19A1]) and metabolism (folylpolyglutamate synthase [FPGS] and gamma-glutamyl hydrolase [GGH]) evaluated in germline DNA (blood) were correlated with treatment outcome. Results Forty-eight evaluable patients (14 females and 34 males) received a median of four cycles (range, one to 20 cycles). The most common grade 3 or 4 nonhematologic adverse events (AEs) were fatigue (13%), dyspnea (10%), and thrombosis (10%). Grade 3 or 4 hematologic AEs were neutropenia (19%) and lymphopenia (13%). Twenty-four (57%; 95% CI, 41% to 72%) of the first 42 patients met the success criteria. Median overall survival (OS) and progression-free survival (PFS) times were 8.6 and 4.0 months, respectively. The exon 6 (2522)C→T polymorphism in SLC19A1 correlated with 3-month progression-free status (P = .01) and with PFS (P = .05). The IVS1(1307)C→T polymorphism in GGH correlated with OS (P = .04). Conclusion The study did not meet its primary end point. However, the median PFS time of 4 months is promising. Pharmacogenetic studies in larger cohorts are needed to definitively identify polymorphisms that predict for survival and toxicity of pemetrexed.