Accuracy of the vedolizumab Clinical Decision Support Tool in Crohn's disease and its association with long-term persistence: A retrospective cohort study.

OBJECTIVE: Vedolizumab is a gut-selective monoclonal antibody approved for moderate-to-severe Crohn's disease. The Clinical Decision Support Tool (CDST) is a tool designed to help predict treatment response and enable personalised therapy. This study aim to evaluate the diagnostic performance of the CDST in a real‑world CD cohort and to explore its association with vedolizumab treatment persistence. PATIENTS AND METHODS: Retrospective, observational, single-centre study including all Crohn's disease patients treated with vedolizumab at our centre. Primary objective was to assess diagnostic accuracy of baseline CDST for clinical remission for clinical remission at weeks 26 and 52. Secondary objectives included evaluation of CDST accuracy for corticosteroid-free clinical remission, normalization of faecal calprotectin, mucosal healing, and deep remission, as well as assessment of VDZ persistence through Kaplan-Meier and Cox regression analyses. RESULTS: Sixty‑four patients were included; 34.38% had fistulizing Crohn's disease, 73.4% prior anti‑TNF exposure, and 48.4% previous intestinal surgery. Baseline mean CDST was 19.36 (SD 3.81), with 62.50% classified as high‑probability responders. AUCs for clinical remission were 0.57 (week 26) and 0.64 (week 52), 0.52 (w26) and 0.64 (w52) for corticosteroid-free clinical remission. VDZ was discontinued in 32.81% of patients over a mean follow‑up of 2.85 years. Baseline CDST was not associated with VDZ persistence (HR 0.98 [0.88-1.09], p = 0.6696). CONCLUSIONS: In this real-world CD cohort, CDST showed poor diagnostic accuracy and did not predict treatment persistence.