Citations

Abstract PURPOSE: Ovarian cancer remains the most lethal gynecological malignancy in the United States even though there are a number of treatment options. For the newly diagnosed ovarian cancer patient, treatment is standard with the majority of patients receiving first-line platinum/taxol treatment following surgical debulking or as part of a neo-adjuvant treatment regimen. Standard response assessment to this chemotherapy combination depends on lengthy clinical follow-up of at least 6 months following the conclusion of the chemotherapy. This course is initially effective in 70-80% of patients, but 20-30% will relapse within the 6 months post-chemotherapy or not respond at all. Additionally, most of the initial responders will also relapse. Early prediction of the patients whose cancers do not respond could lead to earlier intervention with more effective therapy. RESULTS: To perform this prediction, we developed a test utilizing live tumor tissue and 3D cell culture to predict the response of ovarian cancer patients to standard platinum and taxol chemotherapy along with the standard agents used for relapse patients. To validate the assay, we performed a prospective trial involving 86 women with newly diagnosed ovarian cancer from whom live tumor tissue was recovered at surgical resection prior to chemotherapy. Of the 79 patients whose tissues yielded a successful assay result, 27 had sufficient clinical follow-up to determine the accuracy of the response predictions made by the assay. Assay response predictions were made within 7 days following surgery while clinical response was not determined until 6 months or more following the conclusion of first-line chemotherapy. Assay results predicted first-line chemotherapy response in 100% of clinical responders (19 of 19) and first-line chemotherapy non-response in 62.5% of clinical non-responders (5 of 8) as defined by CA-125 and radiographic surveillance. This response prediction was statistically significant by Fisher's Exact test, p < 0.001. The sensitivity of the assay was 86% while the specificity was 100%. When the assay results were examined in terms of progression free survival, 19 of 19 patients identified as responders by the assay remained progression free at least 6 months post-chemotherapy with 14 remaining progression free 10 or more months post-chemotherapy. In contrast, of the 8 assay non-responders, 3 were refractory with progression within 3 months of chemotherapy conclusion and 2 progressed less than 6 months post-chemotherapy with a mean progression free survival of 4.5 months. CONCLUSIONS: Our rapid, ex vivo, 3D cellular assay is capable of accurate patient specific response prediction of first-line combination therapy in newly diagnosed ovarian cancer patients and can serve as a prognostic indicator of progression free survival. This preliminary clinical validation shows the significant potential of this assay as a future tool in personalized cancer care for ovarian cancer patients. Citation Format: Stephen Shuford, Jeffrey Elder, Larry Puls, John Weroha, Xiaonan Hou, Valentina Zanfagnin, Alpa Nick, Michael P. Stany, Larry Maxwell, Thomas Conrads, Chris Corless, Anil K. Sood, Matthew Gevaert, Howland E. Crosswell, and Teresa M. DesRochers. PROSPECTIVE CLINICAL VALIDATION OF EX VIVO, PATIENT-SPECIFIC RESPONSE PREDICTION TO FIRST-LINE CHEMOTHERAPY [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr TMIM-069.

Abstract Background There is a critical need to identify patient characteristics associated with long-term ovarian cancer survival. Methods Quality of life (QOL), measured by the Functional Assessment of Cancer Therapy-Ovarian-Trial Outcome Index (FACT-O-TOI), including physical, functional, and ovarian-specific subscales, was compared between long-term survivors (LTS) (8+ years) and short-term survivors (STS) (<5 years) of GOG 218 at baseline; before cycles 4, 7, 13, 21; and 6 months post-treatment using linear and longitudinal mixed models adjusted for covariates. Adverse events (AEs) were compared between survivor groups at each assessment using generalized linear models. All P values are 2-sided. Results QOL differed statistically significantly between STS (N = 1115) and LTS (N = 260) (P < .001). Baseline FACT-O-TOI and FACT-O-TOI change were independently associated with long-term survival (odds ratio = 1.05, 95% confidence interval = 1.03 to 1.06 and odds ratio = 1.06, 95% confidence interval = 1.05 to 1.07, respectively). A 7-point increase in baseline QOL was associated with a 38.0% increase in probability of LTS, and a 9-point increase in QOL change was associated with a 67.0% increase in odds for LTS. QOL decreased statistically significantly with increasing AE quartiles (cycle 4 quartiles: 0-5 vs 6-8 vs 9-11 vs ≥12 AEs, P = .01; cycle 21 quartiles: 0-2 vs 3 vs 4-5 vs ≥6 AEs, P = .001). Further, LTS reported statistically significantly better QOL compared with STS (P = .03 and P = .01, cycles 4 and 21, respectively), with similar findings across higher AE grades. Conclusions Baseline and longitudinal QOL change scores distinguished LTS vs STS and are robust prognosticators for long-term survival. Results have trial design and supportive care implications, providing meaningful prognostic value in this understudied population.

Abstract Guanylate cyclase C (GUCY2C) is a tumor-suppressing receptor silenced by loss of expression of its luminocrine hormones guanylin and uroguanylin early in colorectal carcinogenesis. This observation suggests oral replacement with a GUCY2C agonist may be an effective targeted chemoprevention agent. Linaclotide is an FDA-approved oral GUCY2C agonist formulated for gastric release, inducing fluid secretion into the small bowel to treat chronic idiopathic constipation. The ability of oral linaclotide to induce a pharmacodynamic response in epithelial cells of the colorectum in humans remains undefined. Here, we demonstrate that administration of 0.87 mg of oral linaclotide daily for 7 days to healthy volunteers, after oral colon preparation with polyethylene glycol solution (MoviPrep), activates GUCY2C, resulting in accumulation of its product cyclic (c)GMP in epithelial cells of the cecum, transverse colon, and distal rectum. GUCY2C activation by oral linaclotide was associated with homeostatic signaling, including phosphorylation of vasodilator-stimulated phosphoprotein and inhibition of proliferation quantified by reduced Ki67-positive epithelial cells. In the absence of the complete oral colonoscopy preparation, linaclotide did not alter cGMP production in epithelial cells of the colorectum, demonstrating that there was an effect related to the laxative preparation. These data show that the current FDA-approved formulation of oral linaclotide developed for small-bowel delivery to treat chronic idiopathic constipation is inadequate for reliably regulating GUCY2C in the colorectum to prevent tumorigenesis. The study results highlight the importance of developing a novel GUCY2C agonist formulated for release and activity targeted to the large intestine for colorectal cancer prevention. Cancer Prev Res; 10(6); 345–54. ©2017 AACR.

ABSTRACT Hepatitis C virus (HCV) protease inhibitors combined with pegylated alfa interferon-ribavirin have demonstrated improved efficacy compared with pegylated alfa interferon-ribavirin alone for the treatment of chronic hepatitis C. Asunaprevir (BMS-650032), a novel HCV NS3 protease inhibitor in clinical development, was evaluated for safety, antiviral activity, and resistance in four double-blind, placebo-controlled, sequential-panel, single- and multiple-ascending-dose (SAD and MAD) studies in healthy subjects or subjects with chronic HCV genotype 1 infection. In SAD studies, subjects (healthy or with chronic HCV infection) were randomized to receive asunaprevir in dose groups of 10 to 1,200 mg or a placebo. In MAD studies, healthy subjects were randomized to receive asunaprevir in dose groups of 10 to 600 mg twice daily or a placebo for 14 days; subjects with HCV infection received asunaprevir in dose groups of 200 to 600 mg twice daily, or a placebo, for 3 days. Across all four studies, headache and diarrhea were the most frequent adverse events in asunaprevir recipients. Asunaprevir at doses of 200 to 600 mg resulted in rapid HCV RNA decreases from the baseline; maximal mean changes in HCV RNA over time were 2.7 and 3.5 log 10 IU/ml in the SAD and MAD studies, respectively. No enrichment of signature asunaprevir-resistant viral variants was detected. In conclusion, the novel NS3 protease inhibitor asunaprevir, when administered at single or multiple doses of 200 to 600 mg twice daily, is generally well tolerated, achieving rapid and substantial decreases in HCV RNA levels in subjects chronically infected with genotype 1 HCV.