Short term effectiveness of ustekinumab versus vedolizumab in Crohn's disease after failure of anti-TNF agents: An observational comparative study design with a Bayesian analysis

Background: Crohn's disease (CD) is a debilitating gastrointestinal disease with complex etiology. Although effective, recipients of anti-tumor necrosis factor (TNF) agents may experience primary or secondary nonresponse, necessitating alternative treatments. This study is intended to compare the short-term effectiveness of ustekinumab and vedolizumab in treating CD after failure of multiple lines of anti-TNF therapy using real-world data. Methods: A retrospective study was conducted at a tertiary hospital in Dammam, Saudi Arabia, including adults (≥18 years old) with CD who did not respond to anti-TNF therapy. Primary endpoints were clinical improvement per the Harvey-Bradshaw Index (HBI) scores and remission at 12 weeks on an ordinal outcome scale. Secondary endpoints included clinical, biochemical, and endoscopic remission; clinical response; corticosteroid-free days; and cumulative steroid dose. Proportional odds and logistic regression Bayesian models were used to analyze outcomes, and the probability of treatment effectiveness was calculated from the posterior distribution. Results: The study included 101 patients (ustekinumab, n = 71 and vedolizumab, n = 30) with a median age of 32 years (IQR: 26.0-38.0); 54.4% were male. At 12 weeks, the HBI endpoint showed an adjusted odds ratio (aOR) = 0.60 (95% confidence interval [CI]: 0.25-1.31), favoring ustekinumab, with a 75% probability of treatment effectiveness over vedolizumab. The clinical ordinal scale had an aOR = 0.61 (95% CI: 0.26-1.35) with a 73% probability of effectiveness for ustekinumab. Ustekinumab was also associated with favorable outcomes in secondary endpoints, reaching up to a 90% probability of effectiveness. Conclusion: In CD patients with anti-TNF failure, ustekinumab was more effective than vedolizumab in the short term. These real-world insights contribute to understanding CD management but require validation in larger prospective studies and randomized controlled trials.