Stricture dynamics and prognosis during biologic therapy in ileal Crohn’s disease: a real-world cohort

BACKGROUND AND AIMS: Clinicians need data on the responsiveness of ileal strictures of Crohn's disease (CD) to biologic therapy, yet most trials prioritize mucosal healing. We quantified short‑term changes in ileal strictures under biologic treatment and evaluated their prognostic relevance. PATIENTS AND METHODS: In a post hoc analysis of a prospective cohort, consecutive patients with ileal or ileocolonic CD initiating or switching a biologic (anti‑tumor necrosis factor [TNF], ustekinumab [UST], or vedolizumab [VDZ]) underwent segment‑specific endoscopic assessment at baseline and 6 months. The primary outcome was resolution or progression of strictures at 6 months. Secondary outcomes included time‑to‑event analyses for hospitalization and surgery. RESULTS: Among the 170 patients, the 6‑month stricture resolution and progression rates were 30.9% and 15.7%, respectively. There were no significant differences in stricture dynamics between anti‑TNF agents, UST, and VDZ (P = .443 for resolution and P = .167 for progression). Baseline strictures did not predict outcomes; however, strictures present at 6 months were associated with higher risks of hospitalization (P = .006) and surgery (P = .024), particularly when located in the non-terminal ileum. Clinical, biochemical, and endoscopic activity improved overall during follow‑up. CONCLUSIONS: The 6‑month stricture status, especially non-terminal ileal disease, carried prognostic significance. Because stricture dynamics did not differ across biologic classes, the presence of strictures alone should not constrain agent selection.