Introduction

Treatment goals in inflammatory bowel disease (IBD) have evolved beyond symptom control to include mucosal healing, prevention of disease-related complications, improvement of health-related quality of life, and reduction of long-term disability, as outlined by the STRIDE II initiative¹. Despite significant progress in the development of advanced therapies (ADTs), up to 50% of IBD patients fail to respond to currently available treatments, underscoring the urgent need for new therapies, which are investigated in randomized clinical trials (RCTs). However, stringent eligibility criteria in RCTs limit the inclusion of real-world IBD patients, potentially compromising the generalizability of trial findings to daily clinical practice.

Aims & Methods

The aim of this study was to evaluate the proportion of real-life IBD patients who would be eligible for ongoing RCTs and to assess the representativeness of this population. Moreover, we aimed to identify the most frequently unmet eligibility criteria leading to patient exclusion and to characterize the clinical profiles that differentiate eligible from ineligible patients.
This prospective, observational, multicenter study was conducted between October 2023 and October 2024 at 2 tertiary IBD referral centers: the Fondazione Policlinico Universitario “A. Gemelli” in Rome, Italy, and the Crohn’s & Colitis Center at the University of Miami, USA. Consecutive patients with IBD indicated for a new ADT were enrolled. Each patient was systematically screened for inclusion and exclusion criteria across all actively recruiting phase 2b and 3 RCTs available at each center at the time of evaluation (6 RCTs in Rome: 4 UC and 2 CD; 5 RCTs in Miami: 3 UC and 2 CD).

Results

A total of 166 IBD patients (69 UC and 97 CD) were enrolled, with 129 patients from the Italian cohort and 37 from the American cohort. Among UC patients, only 16 (23.2%) met the eligibility criteria for at least 1 RCT, whereas 53 (76.8%) were deemed ineligible (p<0.001). In the CD group, just 10 patients (10.3%) were eligible for at least 1 RCT, compared to 87 (89.7%) who were not (p<0.001). The most common reasons for ineligibility among UC patients included: Modified Mayo score not within the required range of 5–9 (50.7%), absence of bowel urgency (63.8%), Mayo Endoscopic Subscore <2 (39.1%), failure to comply with ADT washout requirements (56.5%), insufficient number of prior ADT failures (39.0%), and recent use of topical 5-ASA or steroids within 4 weeks prior to screening (62.3%).
In CD patients, the most frequently unmet criterion was a CDAI between 220 and 450 (92.8%), followed by insufficiently liquid stool frequency (≥4 very soft or liquid stools/day; 75.3%), SES-CD<6 (39.2%), and the presence of CD-related complications such as strictures or fistulas (13.1%).

Conclusion

The majority of real-life IBD patients, particularly those with CD, are ineligible for participation in current RCTs—primarily due to relatively mild disease activity or ongoing need for concomitant therapies that are not permitted by trial protocols. Importantly, many real-world CD patients initiate new ADTs based on radiologic signs of disease activity, the presence of disease complications, or as prophylaxis for post-surgical recurrence, rather than clinical activity scores alone. Similarly, UC patients may require ADTs even in the context of corticosteroid dependence and low-grade disease activity. These findings underscore the need to revisit and broaden eligibility criteria in future RCTs to ensure greater external validity and alignment with the heterogeneity of real-life IBD population.

References

1. Turner D, Ricciuto A, Lewis A, D'Amico F, Dhaliwal J, Griffiths AM, Bettenworth D, Sandborn WJ, Sands BE, Reinisch W, Schölmerich J, Bemelman W, Danese S, Mary JY, Rubin D, Colombel JF, Peyrin-Biroulet L, Dotan I, Abreu MT, Dignass A; International Organization for the Study of IBD. STRIDE-II: An Update on the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) Initiative of the International Organization for the Study of IBD (IOIBD): Determining Therapeutic Goals for Treat-to-Target strategies in IBD. Gastroenterology. 2021 Apr;160(5):1570-1583. doi: 10.1053/j.gastro.2020.12.031. Epub 2021 Feb 19. PMID: 33359090.