Mark A. Samaan

Development and validation of a histological index for UC

Objective Although the Geboes score (GS) and modified Riley score (MRS) are commonly used to evaluate histological disease activity in UC, their operating properties are unknown. Accordingly, we developed an alternative instrument. Design Four pathologists scored 48 UC colon biopsies using the GS, MRS and a visual analogue scale global rating. Intra-rater and inter-rater reliability for each index and individual index items were measured using intraclass correlation coefficients (ICCs). Items with high reliability were used to develop the Robarts histopathology index (RHI). The responsiveness/validity of the RHI and multiple histological, endoscopic and clinical outcome measures were evaluated by analyses of change scores, standardised effect size (SES) and Guyatts responsiveness statistic (GRS) using data from a clinical trial of an effective therapy. Results Inter-rater ICCs (95% CIs) for the total GS and MRS scores were 0.79 (0.63 to 0.87) and 0.80 (0.69 to 0.87). The correlation estimates between change scores in RHI and change score in GS and MRS were 0.75 (0.67 to 0.82) and 0.84 (0.79 to 0.88), respectively. The SES and GRS estimates for GS, MRS and RHI were: 1.87 (1.54 to 2.20) and 1.23 (0.97 to 1.50), 1.29 (1.02 to 1.56) and 0.88 (0.65 to 1.12), and 1.05 (0.79 to 1.30) and 0.88 (0.64 to 1.12), respectively. Conclusions The RHI is a new histopathological index with favourable operating properties.

A Systematic Review of the Measurement of Endoscopic Healing in Ulcerative Colitis Clinical Trials: Recommendations and Implications for Future Research

Background:Assessment of endoscopic disease activity, as measured by various endoscopic evaluative instruments, is an essential part of quantifying disease activity in clinical trials in patients with ulcerative colitis (UC). Evaluative instruments have specific definitions and operating properties that influence the interpretation of clinical trial results. Our objective was to systematically review all endoscopic evaluative instruments that measure endoscopic disease activity in UC and to describe their definitions and operating characteristics (reliability, responsiveness, and predictive validity). Methods:We performed a systematic review of evaluative instruments assessing endoscopic disease activity in UC. MEDLINE (Ovid), EMBASE (Ovid), PubMed, the Cochrane Library (CENTRAL), and Digestive Disease Week abstracts of clinical trials were searched from inception to January 2013. Results:In total, 5885 studies were identified and screened for inclusion criteria. Four hundred twenty-two studies involving 31 evaluative instruments were identified. Two types of indices were found, numerical scoring systems and stepwise grading scales. Conclusions:Both the endoscopic evaluative instrument selected and the definition chosen for mucosal healing affect the validity of assessing endoscopic disease activity during a clinical trial for UC. Currently, the sigmoidoscopic component of the Mayo Score and the ulcerative colitis endoscopic index of severity show the most promise as reliable evaluative instruments of endoscopic disease activity. However, further validation is required.

Reproducibility of histological assessments of disease activity in UC.

Objective Histopathology is potentially an important outcome measure in UC. Multiple histological disease activity (HA) indices, including the Geboes score (GS) and modified Riley score (MRS), have been developed; however, the operating properties of these instruments are not clearly defined. We assessed the reproducibility of existing measures of HA. Design Five experienced pathologists with GI pathology fellowship training and expertise in IBD evaluated, on three separate occasions at least two weeks apart, 49 UC colon biopsies and scored the GS, MRS and a global rating of histological severity using a 100 mm visual analogue scale (VAS). The reproducibility of each grading system and for individual instrument items was quantified by estimates of intraclass correlation coefficients (ICCs) based on two-way random effects models. Uncertainty of estimates was quantified by 95% two-sided CIs obtained using the non-parametric cluster bootstrap method. Biopsies responsible for the greatest disagreement based on the ICC estimates were identified. A consensus process was used to determine the most common sources of measurement disagreement. Recommendations for minimising disagreement were subsequently generated. Results Intrarater ICCs (95% CIs) for the total GS, MRS and VAS scores were 0.82 (0.73 to 0.88), 0.71 (0.63 to 0.80) and 0.79 (0.72 to 0.85), respectively. Corresponding inter-rater ICCs were substantially lower: 0.56 (0.39 to 0.67), 0.48 (0.35 to 0.66) and 0.61 (0.47 to 0.72). Correlation between the GS and VAS was 0.62 and between the MRS and VAS was 0.61. Conclusions Although ‘substantial’ to ‘almost perfect’ ICCs for intrarater agreement were found in the assessment of HA in UC, ICCs for inter-rater agreement were considerably lower. According to the consensus process results, standardisation of item definitions and modification of the existing indices is required to create an optimal UC histological instrument.

Safety and Feasibility of Using the Second-Generation Pillcam Colon Capsule to Assess Active Colonic Crohn's Disease.

BACKGROUND & AIMS The second-generation Pillcam Colon Capsule Endoscope (PCCE-2; Given Imaging Ltd, Yoqneam, Israel) is an ingestible capsule for visualization of the colon. We performed a multicenter pilot study to assess its safety and feasibility in evaluating the severity of Crohns disease (CD). METHODS In a prospective study, 40 patients with active colonic CD underwent PCCE-2 and optical colonoscopy procedures. Using both techniques, we generated values for the Crohns Disease Endoscopic Index of Severity (CDEIS), the Simple Endoscopic Score for CD, and global evaluation of lesion severity. In the first stage of the study, we calculated the correlation between PCCE-2 and optical colonoscopy scores. In the second stage, we performed interobserver agreement analysis for a random subset of 20 PCCE-2 recordings, graded in duplicate by 2 independent readers. RESULTS There was substantial agreement between PCCE-2 and optical colonoscopy in the measurement of the CDEIS (intraclass correlation coefficient [ICC], 0.65; 95% confidence interval [CI], 0.43-0.80). There was substantial interobserver agreement between 2 independent PCCE-2 readers for the CDEIS (ICC, 0.67; 95% CI, 0.35-0.86) and the Simple Endoscopic Score for CD (ICC, 0.66; 95% CI, 0.32-0.85). However, the PCCE-2 scoring systematically underestimated the severity of disease compared with optical colonoscopy; based on our results, PCCE-2 detected colonic ulcerations with 86% sensitivity and 40% specificity. No adverse events were observed and PCCE-2 was better tolerated than colonoscopy. CONCLUSIONS PCCE-2 is feasible, safe, and well tolerated for the assessment of mucosal CD activity in selected populations. Larger studies are needed to assess its operating characteristics further. European clinical trials database number: 2014-003854-15.

An Update on Anti-TNF Agents in Ulcerative Colitis

Anti-tumor necrosis factor-α agents are key therapeutic options for the treatment of ulcerative colitis. Their efficacy and safety have been shown in large randomized controlled trials. The key evidence gained from these trials of infliximab, adalimumab, and golimumab is reviewed along with their effect on mucosal healing and long-term outcomes. Also reviewed are methods for optimizing their effectiveness, including therapeutic drug monitoring and treat-to-target strategies. Finally, remaining unresolved questions regarding their role and effectiveness are considered including how these may be addressed in future clinical trials.

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

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.

Sa1198 Agreement Among Experts in the Endoscopic Evaluation of Postoperative Recurrence in Crohn's Disease Using the Rutgeerts Score

Geboes-Structural 0.70 (0.60 0.79) 0.80 (0.74 0.86) Geboes-Chronic inflammatory infiltrate 0.64 (0.54 0.74) 0.81 (0.75 0.86) Geboes-Lamina propria eosinophils 0.26 (0.18 0.37) 0.59 (0.52 0.66) Geboes & Modified Riley-Lamina propria neutrophils 0.37 (0.27 0.49) 0.59 (0.51 0.68) Modified Riley-Neutrophils in epithelium 0.47 (0.37 0.59) 0.71 (0.64 0.78) Geboes-Crypt destruction 0.34 (0.24 0.47) 0.61 (0.54 0.69) Geboes-Erosion or ulceration 0.56 (0.45 0.67) 0.78 (0.73 0.84)

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

Minimising placebo response is essential for drug development.

Vedolizumab: toward a personalized therapy paradigm for people with ulcerative colitis

Ulcerative colitis (UC) is a chronic relapsing and remitting inflammatory bowel disease, with a characteristic leukocytic infiltration of the mucosa. Immunosuppression including anti-TNF-α therapy is a mainstay of treatment for many; however, systemic immunosuppression is not universally effective and is associated with potential side effects. The gut-tropic integrin α4β7, which is expressed on leukocytes, mediates migration from the circulation to the intestinal mucosa. Vedolizumab is a monoclonal antibody which blocks the egress of leukocytes via α4β7, preventing accumulation in the mucosa, and attenuating inflammation without systemic immunosuppression. Vedolizumab has been evaluated in UC in a phase III trial, demonstrating efficacy as both an induction and a maintenance agent. In this article, we review the clinical trial data and also explore the growing body of “real-world” effectiveness data, investigating response and remission rates of vedolizumab in clinical practice. In addition, we review the increasing volume of data supporting the reassuring safety profile associated with vedolizumab.

The development of a magnetic resonance imaging index for fistulising Crohn's disease

Magnetic resonance imaging (MRI) is the gold standard for assessment of perianal fistulising Crohns disease (CD). The Van Assche index is the most commonly used MRI fistula index.