Outcomes of Passable and Non-passable Strictures in Clinical Trials of Crohn's Disease: A Post-hoc Analysis

There is paucity of evidence on the reversibility of Crohn's disease [CD]-related strictures treated with therapies. We aimed to describe the clinical and endoscopic outcomes of CD patients with non-passable strictures.

This was a post-hoc analysis of three large CD clinical trial programmes examining outcomes with infliximab, ustekinumab, and azathioprine, which included data on 576 patients including 105 with non-passable strictures and 45 with passable strictures, as measured using the Simple Endoscopic Score for Crohn's Disease [SES-CD]. The impact of non-passable strictures on achieving clinical remission [CR] and endoscopic remission [ER] was assessed using multivariate logistic regression models. CR was defined as a Crohn's Disease Activity Index [CDAI] <150, clinical response as a CDAI reduction of ≥100 points, and ER as SES-CD score <3.

After 1 year of treatment, patients with non-passable strictures demonstrated the ability to achieve passable or no strictures in 62.5% of cases, with 52.4% and 37.5% attaining CR and ER, respectively. However, patients with non-passable strictures at baseline were less likely to demonstrate symptom improvement compared with those with passable or no strictures, with reduced odds of 1-year CR (adjusted odds ratio [aOR] 0.17, 95% CI 0.03-0.99, p = 0.048). No significant differences were observed between patients with non-passable strictures at baseline and those with passable or no strictures in rates of ER [aOR 0.82, 95% CI 0.23-2.85, p = 0.751] at 1 year.

Patients with non-passable strictures can achieve symptomatic and endoscopic remission when receiving therapies used to treat CD, although they are less likely to obtain CR compared with patients without non-passable strictures. These findings support the importance of balancing the presence of non-passable strictures in trial arms.