Rupert W. Leong

Expert review of gastroenterology & hepatology • January 27, 2025

Thanaboon Chaemsupaphan, Arteen Arzivian, Rupert Leong

Ulcerative colitis is a chronic inflammatory condition of the colon driven by aberrant immune activation. Although advanced medical therapies form the cornerstone of ulcerative colitis management, unmet needs include failure to induce and sustain remission in a substantial proportion of patients and in managing acute severe ulcerative colitis. We review new treatment strategies that might improve patient outcomes in the management of moderate-to-severe ulcerative colitis. A literature search was conducted using the PubMed database, including studies published from inception to October 2024, selected for their relevance. Recognizing current limitations, this article reviews strategies to improve treatment outcomes in ulcerative colitis using advanced therapies. These approaches include early treatment initiation, dose optimization, positioning newer agents as first-line therapies, combination therapy, targeting novel therapeutic endpoints, and the management of acute severe ulcerative colitis. The strategies discussed may contribute to establishing new standards of care aimed at achieving long-term remission and enhancing patient outcomes. Personalized therapy, which tailors treatment based on individual disease characteristics and risk factors, is anticipated to become a critical aspect of delivering more effective care in the future.

Journal Of Crohn's & Colitis • March 11, 2025

Suha Abushamma, Tesfaye Yadete, Neil Nero, Katherine Falloon, Claire Parker, Maria Abreu, Vineet Ahuja, Alessandro Armuzzi, Willem Bemelman, David Bruining, Parakkal Deepak, Axel Dignass, Iris Dotan, Brian Feagan, Clifton Fulmer, Jonas Halfvarson, Ailsa Hart, Stefan Holubar, Rupert Leong, Christopher Ma, Fernando Magro, Jeffrey Mccurdy, Neeraj Narula, Julian Panés, Tim Raine, Miguel Regueiro, Gerhard Rogler, Siddharth Singh, Miles Sparrow, Antonino Spinelli, Julie Van Koughnett, Sudheer Vuyyuru, Virginia Solitano, Yuhong Yuan, Vipul Jairath, Florian Rieder

Objective: Over 10% of patients with Crohn's disease require permanent ileostomy. We aimed to summarize the existing data on diagnosis, definitions of recurrence, and management of Crohn's disease patients with permanent ileostomy. Methods: MEDLINE, Embase, and CENTRAL databases were searched from inception to February 6, 2024. Randomized controlled trials, cohort and cross-sectional studies, and case series of more than 5 patients reporting on postoperative recurrence or the need for surgery in patients with Crohn's disease and permanent ileostomy were included. Search results were independently screened, and full text of all titles meeting eligibility criteria was obtained. Outcomes of interest included diagnostic techniques, recurrence definitions, and management approaches. We estimated pooled rates (with 95% confidence interval [CI]) of recurrence. Results: Thirty cohort studies including 2055 Crohn's patients with permanent ileostomy were included (53% female, median age at the time of ileostomy creation 32 years, the most common reason for ileostomy was refractory disease). The postoperative recurrence rate was 27% (95% CI, 21.3-33.3, 26 studies, 451/1805 patients). Modalities for diagnosis of Crohn's disease recurrence were symptoms (15 studies), endoscopy (4 studies), histology from endoscopic biopsies (2 studies), imaging (5 studies), and surgery (22 studies). The reported definitions of recurrence for each modality were heterogeneous. Conclusions: There is a lack of standardized monitoring tools and criteria for diagnosing recurrence in patients with Crohn's disease and permanent ileostomy. The results of this systematic review will form the basis of a global expert recommendation exercise focused on developing management standards and trial endpoints for this condition.

The Lancet. Gastroenterology & Hepatology • December 02, 2024

Christopher Ma, Reena Khanna, Bryan Maguire, Guangyong Zou, Brian Bressler, Pieter Hindryckx, Mahmoud Mosli, Miles Sparrow, Ailsa Hart, Rupert Leong, David Rubin, Julie Rémillard, Lisa Shackelton, Geert D'haens, Silvio Danese, Laurent Peyrin Biroulet, Bruce Sands, Remo Panaccione, Brian Feagan, Vipul Jairath

Background: Endoscopy is essential for measuring luminal disease activity in Crohn's disease. Existing indices for evaluating endoscopic Crohn's disease activity are only modestly correlated with clinical disease activity, contain items with ambiguous definitions and poor interobserver reliability, and do not have validated thresholds for defining clinically relevant changes. To address these issues, we conducted a multiphase study to develop and validate a novel endoscopic index for Crohn's disease. Methods: Paired baseline and post-induction ileocolonoscopy videos from a phase 3b adalimumab trial (NCT00348283) and phase 2 risankizumab trial (NCT02031276) were assessed by multiple central readers using candidate endoscopic items with face validity derived using modified RAND/UCLA appropriateness methods. The four readers were masked to all clinical information, including treatment assignment and patient symptom scores. A total of 112 and 99 paired ileocolonoscopy videos with treatment assignment were available from the adalimumab trial and risankizumab trial, respectively; after the four readers assessed the 112 videos, two readers then reassessed 44 post-treatment videos to assess inter-rater reliability in index development. Items with acceptable inter-rater reliability (with an intraclass correlation coefficient [ICC] of ≥0·41) and responsiveness (win probability [WinP], the probability that a patient receiving active treatment has a better endoscopy score than a patient receiving placebo, of ≥0·56) were included as covariables in regression for model building with internal validation with bootstrapping. External validation was conducted using the paired videos from the risankizumab trial. Results: Ten endoscopic items met ICC and WinP thresholds and were considered for novel index development. They included items from the SES-CD (presence and size of ulcers, extent of ulcerated surface, and extent of affected surface) and CDEIS (percentage of surface involved by Crohn's disease, percentage of ulcerated surface, deep ulceration, and superficial ulceration) and exploratory items (presence of Crohn's disease-related lesions, Crohn's disease-related lesion severity, and Crohn's disease-related lesion involvement). The final model, Endoscopic ulcer Activity Score for Evaluating CD (EASE-CD), included the presence and size of ulcerations measured on an ordinal scale of 0 (none), 1 (ulcers <5 mm), 2 (ulcers between 5 mm and 20 mm), and 3 (ulcers >20 mm); the presence or absence of deep ulcerations measured dichotomously, with 0 for absent and 1 for present; and the proportion of ulcerated surface area, expressed as a continuous proportion from 0-1, with each item evaluated and averaged across visualised bowel segments. The total score ranges from 0-100 with higher scores indicating greater endoscopic activity. The r2 and optimism adjusted r2 of EASE-CD in internal validation were 0·608 and 0·554, and the index was well calibrated with a slope of 0·983. In external validation, the adjusted r2 was 0·565 and the calibration slope was 0·997. EASE-CD also demonstrated substantial inter-rater reliability (ICC 0·798 [95% CI 0·711-0·836]) and a large degree of responsiveness (WinP 0·769 [95% CI 0·658-0·851], p<0·001) in external validation. A 10-point reduction in EASE-CD had 82·4% specificity (95% CI 78·6-86·0) and 69·9% sensitivity (63·3-76·4) for endoscopic response, defined by at least 50% reduction in SES-CD or CDEIS. Ulcer-free endoscopic remission results in EASE-CD score of 0. Conclusions: EASE-CD is a novel, internally and externally validated continuous measure of endoscopic ulcer activity in Crohn's disease that is reliable and responsive to treatment. Background: None.

Crohn's & Colitis 360 • October 03, 2024

Thanaboon Chaemsupaphan, Aviv Pudipeddi, Huiyu Lin, Sudarshan Paramsothy, Viraj Kariyawasam, Melissa Kermeen, Rupert Leong

Vedolizumab is s gut-selective advanced therapy that is safe and efficacious for the treatment of ulcerative colitis (UC). Once patients achieve successful induction, there is a risk of loss of response leading to eventual flare. We aimed to identify these predictive factors and develop a practical scoring system to determine the ongoing efficacy of vedolizumab. We performed logistic regression on prospectively recruited UC subjects from the Vedolizumab Immunomodulator Enforced Withdrawal Study (VIEWS). All patients were in corticosteroid-free clinical remission and endoscopic improvement at baseline and continued vedolizumab. Predictive factors of 2-year corticosteroid-free clinical remission were determined and modeled into the VIEWS score, then validated in a real-world UC cohort. Of 62 patients in the derivation cohort, 48 (77.4%) maintained clinical remission over two years. The predictive factors of remission were female (odds ratio [OR] 6.0, 95% confidence interval [CI], 1.2-29.7), antitumor necrosis factor naive (OR 3.8, 95% CI,1.0-14.0), baseline histological remission (OR 10.8, 95% CI, 2.4-48.4), thiopurine combination (OR 3.6, 95% CI, 0.7-18.0), and fecal calprotectin level ≤250 µg/g (OR 6.3, 95% CI, 0.9-42.2). These factors were incorporated into VIEWS score, yielding an area under the receiver-operating characteristic (AUROC) curve of 0.89 (95% CI, 0.81-0.98) in the prediction of 2-year clinical remission. Of 64 UC patients in the validation cohort, 40 (62.5%) remained in clinical remission at 2 years with AUROC of 0.77 (95% CI, 0.60-0.94). At the cut-off threshold of 4, the VIEWS score identified 2-year clinical remission with a sensitivity of 88.4% and specificity of 63.6%. Our study determined predictive factors and proposed a scoring system of ongoing clinical remission in UC patients on maintenance vedolizumab. In patients at high risk of relapse, combination therapy with thiopurine may be beneficial.

World Journal Of Gastroenterology • September 12, 2024

Thanaboon Chaemsupaphan, Aviv Pudipeddi, Hui-yu Lin, Sudarshan Paramsothy, Viraj Kariyawasam, Melissa Kermeen, Rupert Leong

Background: Ulcerative colitis (UC) is a chronic inflammatory condition requiring continuous treatment and monitoring. There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown. Objective: To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy. Methods: This is a post-hoc analysis of prospective randomized clinical trial (VIEWS) involving UC patients across 8 centers in Australia from 2018 to 2022. Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab. We evaluated vedolizumab serum trough concentrations, presence of anti-vedolizumab antibodies, and clinical outcomes over 48 weeks to assess exposure-response association and impact of thiopurine withdrawal. Results: There were 62 UC participants with mean age of 43.4 years and 42% were females. All participants received vedolizumab as maintenance therapy with 67.7% withdrew thiopurine. Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use, with no anti-vedolizumab antibodies detected. Patients with clinical remission had higher trough concentrations at week 48. In quartile analysis, a threshold of > 11.3 μg/mL was associated with sustained clinical remission, showing a sensitivity of 82.4%, specificity of 60.0%, and an area of receiver operating characteristic of 0.71 (95%CI: 0.49-0.93). Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission. Conclusions: A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial. While thiopurine did not influence vedolizumab levels, its withdrawal may necessitate higher vedolizumab trough concentrations to maintain remission.