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Dive into the research topics where Claire E Parker is active.

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Featured researches published by Claire E Parker.


Alimentary Pharmacology & Therapeutics | 2017

Review article: dose optimisation of infliximab for acute severe ulcerative colitis

Pieter Hindryckx; Gregor Novak; N. Vande Casteele; Debby Laukens; Claire E Parker; Lisa M. Shackelton; Neeraj Narula; Reena Khanna; Parambir S. Dulai; Barrett G. Levesque; William J. Sandborn; Geert R. D'Haens; Brian G. Feagan; Vipul Jairath

Although optimal medical management of acute severe ulcerative colitis (UC) is ill‐defined, infliximab has become a standard of care. Accumulating evidence suggests an increased rate of infliximab clearance in patients with acute severe UC and a reduced colectomy rate with an intensified infliximab induction regimen.


Journal of Crohns & Colitis | 2016

Systematic Review and Meta-analysis: Placebo Rates in Induction and Maintenance Trials of Ulcerative Colitis

Vipul Jairath; Guangyong Zou; Claire E Parker; John K MacDonald; Mahmoud Mosli; Reena Khanna; Lisa M. Shackelton; Margaret K. Vandervoort; Turki AlAmeel; Mohammad Al Beshir; Majid A Almadi; Talal Al-Taweel; Nathan S. S. Atkinson; Sujata Biswas; Thomas P Chapman; Parambir S. Dulai; Mark A. Glaire; Daniël R. Hoekman; A Koutsoumpas; Elizabeth Minas; Mark A. Samaan; Simon Travis; Geert D’Haens; Barrett G. Levesque; William J. Sandborn; Brian G. Feagan

BACKGROUND AND AIMS Minimisation of the placebo responses in randomised controlled trials [RCTs] is essential for efficient evaluation of new interventions. Placebo rates have been high in ulcerative colitis [UC] clinical trials, and factors influencing this are poorly understood. We quantify placebo response and remission rates in UC RCTs and identify trial design factors influencing them. METHODS MEDLINE, EMBASE, and the Cochrane Library were searched from inception through April 2014 for placebo-controlled trials in adult patients with UC of a biological agent, corticosteroid, immunosuppressant, or aminosalicylate. Data were independently doubly extracted. Quality was assessed using the Cochrane risk of bias tool. RESULTS In all, 51 trials [48 induction and 10 maintenance phases] were identified. Placebo response and remission rates were pooled according to random-effects models, and mixed-effects meta-regression models were used to evaluate effects of study-level characteristics on these rates. Pooled estimates of placebo remission and response rates for induction trials were 10% (95% confidence interval [CI] 7-13%) and 33% [95% CI 29-37%], respectively. Corresponding values for maintenance trials were 19% [95% CI 11-30%] and 22% [95% CI 17-28%]. Trials enrolling patients with more active disease confirmed by endoscopy [endoscopy subscore ≥ 2] were associated with lower placebo rates. Conversely, placebo rates increased with increasing trial duration and number of study visits. CONCLUSIONS Objective assessment of greater disease activity at trial entry by endoscopy lowered placebo rates, whereas increasing trial duration and more interactions with healthcare providers increased placebo rates. These findings have important implications for design and conduct of clinical trials.


Gastroenterology | 2016

Efficient Early Drug Development for Ulcerative Colitis

Reena Khanna; Vipul Jairath; Niels Vande Casteele; Mahmoud Mosli; Guangyong Zou; Claire E Parker; Barrett G. Levesque; William J. Sandborn; Geert D’Haens; Brian G. Feagan

69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 Aapproved for the treatment of ulcerative colitis (UC), new agents are required for patients who are unresponsive to conventional management (Supplementary Appendix 1). Moreover, some patients who have responded to currently available therapies may benefit from improved approaches to treatment. Although innovative therapies hold promise, important barriers to development programs are recognizable. First, the cost of drug development continues to increase, which restricts the number of new therapies that can be evaluated. Second, limited numbers of patients are available for enrollment into competing programs. Third, current study designs that mandate multiple arms for dose finding require large patient numbers and are time consuming. Fourth, the regulatory environment has become increasing complex. Finally, new technologies have led to evolution of highly rigorous trial endpoints. Consequently, fewer drugs successfully complete the registration process than in the past. Because regulatory and patientrelated factors are unlikely to change, new strategies for drug development are needed. Accordingly, trial design must evolve to detect efficacy signals with limited resources. In this article, we describe a novel approach to early drug development in UC.


The American Journal of Gastroenterology | 2017

Systematic Review: Disease Activity Indices in Eosinophilic Esophagitis

Marijn J. Warners; Pieter Hindryckx; Barrett G. Levesque; Claire E Parker; Lisa M. Shackelton; Reena Khanna; William J. Sandborn; Geert R. D'Haens; Brian G. Feagan; Albert J. Bredenoord; Vipul Jairath

Objectives:There is no clear consensus regarding the most appropriate measure(s) of eosinophilic esophagitis (EoE) disease activity. We aimed to identify all scoring indices used for the measurement of disease activity in EoE, appraise their operating properties, and discuss their value as outcome measures.Methods:MEDLINE, EMBASE, and CENTRAL (The Cochrane library) were searched from inception to 11 May 2016. Randomized controlled trials (RCTs), cohort, case–control, and cross-sectional studies that reported outcomes to measure EoE disease activity or response to treatment were eligible. Operating properties of histologic, endoscopic, and patient reported/symptomatic and health-related quality of life measures were critically appraised according to guidelines proposed by the United States Food and Drug Administration.Results:Of 4,373 citations, 130 studies were eligible, of which 20 were RCTs. Although no index met all evaluative criteria, we found that: (1) the EoE histologic scoring system (EoEHSS) is the most valid histologic measure; (2) the Endoscopic Reference Score (EREFS) is the most reliable and responsive endoscopy measure; and (3) the Eosinophilic Esophagitis Activity Index (EEsAI) or the Dysphagia Symptoms Questionnaire (DSQ) had superior construct validity and responsiveness in adults. The Pediatric Quality of Life Inventory EoE was the most valid pediatric symptomatic measure.Conclusions:Current evidence supports the use of the EoEHSS and EREFS as measures of histologic and endoscopic EoE disease activity, respectively, and the EEsAI, DSQ, or Pediatric Quality of Life Inventory EoE as measures of adult and pediatric symptoms. Additional research is needed to optimize endpoint configuration to facilitate development of new therapies.


Alimentary Pharmacology & Therapeutics | 2017

Systematic review with meta-analysis: placebo rates in induction and maintenance trials of Crohn's disease

Vipul Jairath; Guangyong Zou; Claire E Parker; John K MacDonald; Mahmoud Mosli; Turki AlAmeel; M. Al Beshir; Majid A Almadi; Talal Al-Taweel; Nathan S. S. Atkinson; Sujata Biswas; Thomas Chapman; Parambir S. Dulai; Mark A. Glaire; Daniël R. Hoekman; Omar Kherad; Andreas Koutsoumpas; Elizabeth Minas; Sophie Restellini; Mark A. Samaan; Reena Khanna; Barrett G. Levesque; G. D'Haens; William J. Sandborn; B. Feagan

Minimising placebo response is essential for drug development.


Clinical Gastroenterology and Hepatology | 2017

Heterogeneity in Definitions of Endpoints for Clinical Trials of Ulcerative Colitis: A Systematic Review for Development of a Core Outcome Set

Christopher Ma; Remo Panaccione; Richard N. Fedorak; Claire E Parker; Tran M. Nguyen; Reena Khanna; Corey A. Siegel; Laurent Peyrin-Biroulet; Geert D’Haens; William J. Sandborn; Brian G. Feagan; Vipul Jairath

Background & Aims: Advances in development of therapeutic agents for ulcerative colitis (UC) have been paralleled by innovations in trial design. It would be useful to identify a core outcome set, to standardize outcome definitions for efficacy and safety in clinical trials. We performed a systematic review of efficacy and safety outcomes reported in placebo‐controlled randomized controlled trials of patients with UC. Methods: We searched MEDLINE, EMBASE, and the Cochrane Library from inception through March 1, 2017, for placebo‐controlled randomized controlled trials of adult patients with UC treated with aminosalicylates, immunosuppressants, corticosteroids, biologics, and oral small molecules. We collected information on efficacy and safety outcomes, definitions, and measurement tools, stratified by decade of publication. Results: We analyzed data from 83 randomized controlled trials (68 induction and 15 maintenance) comprising 17,737 patients. Clinical or composite‐clinical efficacy outcomes were reported in all trials; the UC Disease Activity Index and Mayo Clinic Score were frequently used to determine clinical response or remission. We found substantial variation in definitions of clinical or composite‐clinical endpoints, with more than 50 definitions of response or remission. Endoscopic factors, histologic features, and fecal or serum biomarkers were used to determine outcomes in 83.1% (69 of 83), 24.1% (20 of 83), and 24.1% (20 of 83) of trials, respectively. A greater proportion of trials published after 2007 reported objective outcomes (96.5% endoscopic, 26.3% histologic, and 36.8% biomarker outcomes), but no standardized definitions of histologic or biomarker endpoints were found. Patient‐reported efficacy and quality‐of‐life outcomes were described in 25 trials (30.1%) and safety outcomes were reported in 77 trials (92.8%). Conclusion: In a systematic review, we found that despite recent advances in clinical trials methods, there is a great deal of variation in definitions of endpoints, including response and remission, in randomized controlled trials of patients with UC. Researchers should identify a core set of outcomes to standardize efficacy and safety reporting in UC clinical trials.Advances in drug development for ulcerative colitis (UC) have been paralleled by innovations in trial design. Development of a core outcome set (COS) to standardize outcome definitions and reporting in clinical trials is desirable. We aim to systematically review the efficacy and safety outcomes reported in UC placebo-controlled RCTs. We searched MEDLINE, EMBASE, and the Cochrane Library from inception through March 1, 2017 for placebo-controlled RCTs in adult patients with UC treated with aminosalicylates, immunosuppressants, corticosteroids, biologics, and oral small molecules. Efficacy and safety outcomes, definitions, and measurement tools were extracted and stratified by decade of publication. Eighty-three RCTs (68 induction, 15 maintenance) were included, enrolling 17,737 patients. Clinical or composite-clinical efficacy outcomes were reported in all trials; the Ulcerative Colitis Disease Activity Index (UCDAI) and the Mayo Clinic Score (MCS) were commonly used tools for assessing clinical response/remission. Remarkably, substantial variability in the definition of clinical or composite-clinical endpoints was observed with over 50 definitions of response or remission utilized. Endoscopic, histologic, and fecal/serum biomarker outcomes were reported in 83.1% (69/83), 24.1% (20/83), and 24.1% (20/83) of RCTs, respectively. A greater proportion of trials published after 2007 reported objective outcomes (96.5% endoscopic, 26.3% histologic, and 36.8% biomarker outcomes), but no standardized definitions of histologic or biomarker endpoints exists. Patient-reported efficacy and quality of life outcomes were described in 25 RCTs (30.1%) and safety outcomes were reported in 77 RCTs (92.8%). Despite recent advances in clinical trials methodology, important heterogeneity in reporting and variability in endpoint definitions still remains. A need exists to develop and validate a COS for UC clinical trials


Gut | 2018

Disease activity indices in coeliac disease: systematic review and recommendations for clinical trials

Pieter Hindryckx; Barrett G. Levesque; Tom Holvoet; Serina Durand; Ceen-Ming Tang; Claire E Parker; Reena Khanna; Lisa M. Shackelton; Geert R. D'Haens; William J. Sandborn; Brian G. Feagan; Benjamin Lebwohl; Daniel A. Leffler; Vipul Jairath

Objective Although several pharmacological agents have emerged as potential adjunctive therapies to a gluten-free diet for coeliac disease, there is currently no widely accepted measure of disease activity used in clinical trials. We conducted a systematic review of coeliac disease activity indices to evaluate their operating properties and potential as outcome measures in registration trials. Design MEDLINE, EMBASE and the Cochrane central library were searched from 1966 to 2015 for eligible studies in adult and/or paediatric patients with coeliac disease that included coeliac disease activity markers in their outcome measures. The operating characteristics of histological indices, patient-reported outcomes (PROs) and endoscopic indices were evaluated for content and construct validity, reliability, responsiveness and feasibility using guidelines proposed by the US Food and Drug Administration (FDA). Results Of 19 123 citations, 286 studies were eligible, including 24 randomised-controlled trials. Three of five PROs identified met most key evaluative criteria but only the Celiac Disease Symptom Diary (CDSD) and the Celiac Disease Patient-Reported Outcome (CeD PRO) have been approved by the FDA. All histological and endoscopic scores identified lacked content validity. Quantitative morphometric histological analysis had better reliability and responsiveness compared with qualitative scales. Endoscopic indices were infrequently used, and only one index demonstrated responsiveness to effective therapy. Conclusions Current best evidence suggests that the CDSD and the CeD PRO are appropriate for use in the definition of primary end points in coeliac disease registration trials. Morphometric histology should be included as a key secondary or co-primary end point. Further work is needed to optimise end point configuration to inform efficient drug development.


BMJ Open | 2017

Development of a core outcome set for clinical trials in inflammatory bowel disease: study protocol for a systematic review of the literature and identification of a core outcome set using a Delphi survey

Christopher Ma; Remo Panaccione; Richard N. Fedorak; Claire E Parker; Reena Khanna; Barrett G. Levesque; William J. Sandborn; Brian G. Feagan; Vipul Jairath

Introduction Crohn’s disease (CD) and ulcerative colitis (UC), the main forms of inflammatory bowel disease (IBD), are chronic, progressive and disabling disorders of the gastrointestinal tract. Although data from randomised controlled trials (RCTs) provide the foundation of evidence that validates medical therapy for IBD, considerable heterogeneity exists in the measured outcomes used in these studies. Furthermore, in recent years, there has been a paradigm shift in IBD treatment targets, moving from symptom-based scoring to improvement or normalisation of objective measures of inflammation such as endoscopic appearance, inflammatory biomarkers and histological and radiographic end points. The abundance of new treatment options and evolving end points poses opportunities and challenges for all stakeholders involved in drug development. Accordingly, there exists a need to harmonise measures used in clinical trials through the development of a core outcome set (COS). Methods and analysis The development of an IBD-specific COS includes four steps. First, a systematic literature review is performed to identify outcomes previously used in IBD RCTs. Second, semistructured qualitative interviews are conducted with key stakeholders, including patients, clinicians, researchers, pharmaceutical industry representatives, healthcare payers and regulators to identify additional outcomes of importance. Using the outcomes generated from literature review and stakeholder interviews, an international two-round Delphi survey is conducted to prioritise outcomes for inclusion in the COS. Finally, a consensus meeting is held to ratify the COS and disseminate findings for application in future IBD trials. Ethics and dissemination Given that over 30 novel therapeutic compounds are in development for IBD treatment, the design of robust clinical trials measuring relevant and standardised outcomes is crucial. Standardising outcomes through a COS will reduce heterogeneity in trial reporting, facilitate valid comparisons of new therapies and improve clinical trial quality.


Alimentary Pharmacology & Therapeutics | 2017

Randomised non-inferiority trial: 1600 mg versus 400 mg tablets of mesalazine for the treatment of mild-to-moderate ulcerative colitis

G. D'Haens; William J. Sandborn; Guangyong Zou; Larry Stitt; P. Rutgeerts; Denise Gilgen; Vipul Jairath; Pieter Hindryckx; Lisa M. Shackelton; Margaret K. Vandervoort; Claire E Parker; C. Muller; Rish K. Pai; O. Levchenko; Y. Marakhouski; M. Horynski; E. Mikhailova; N. Kharchenko; S. Pimanov; B. Feagan

High concentration mesalazine formulations are more convenient than conventional low concentration formulations for the treatment of ulcerative colitis (UC).


Clinical Gastroenterology and Hepatology | 2018

Heterogeneity in Definitions of Efficacy and Safety Endpoints for Clinical Trials of Crohn’s Disease: A Systematic Review

Christopher Ma; Isra M Hussein; Yousef J. Al-Abbar; Remo Panaccione; Richard N. Fedorak; Claire E Parker; Tran M. Nguyen; Reena Khanna; Corey A. Siegel; Laurent Peyrin-Biroulet; Rish K. Pai; Niels Vande Casteele; Geert D’Haens; William J. Sandborn; Brian G. Feagan; Vipul Jairath

Background & Aims Endpoints in randomized controlled trials (RCTs) of Crohn’s disease (CD) are changing. We performed a systematic review of efficacy and safety outcomes reported in placebo‐controlled RCTs of patients with CD. Methods We searched the MEDLINE, EMBASE, and the Cochrane Library through March 1, 2017 for placebo‐controlled RCTs of adult patients with CD treated with aminosalicylates, immunomodulators, corticosteroids, biologics, and oral small molecules. Efficacy and safety outcomes, definitions, and measurement tools were collected and stratified by decade of publication. Results Our final analysis included 116 RCTs (81 induction, 44 maintenance, 7 postoperative prevention trials, comprising 27,263 patients). Clinical efficacy endpoints were reported in all trials; the most common endpoint was CD activity index score. We identified 38 unique definitions of clinical response or remission and 32 definitions of loss of response. Definitions of endoscopic response, remission, and endoscopic healing were also heterogeneous, evaluated using the CD endoscopic index of severity, the simple endoscopic score for CD, ulcer resolution, and Rutgeerts’ Score for postoperative endoscopic appearance. Histologic outcomes were reported in 11.1% of induction trials, 2.3% of maintenance trials, and 14.3% of postoperative prevention trials. Biomarker outcomes were reported in 81.5% induction trials, 68.2% of maintenance trials, and 42.9% of postoperative prevention trials. Safety outcomes were reported in 93.8% of induction trials, 97.7% of maintenance trials, and 85.7% of postoperative prevention trials. Conclusions In this systematic review, we demonstrate heterogeneity in definitions of response and remission, and changes in outcomes reported in RCTs of CD. It is a priority to select a core set of outcomes to standardize efficacy and safety evaluation in trials of patients with CD.

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Brian G. Feagan

University of Western Ontario

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Reena Khanna

University of Western Ontario

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John K MacDonald

University of Western Ontario

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Guangyong Zou

University of Western Ontario

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B. Feagan

Robarts Research Institute

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