Relapse Rates and Predictors for Relapse in Ulcerative Colitis and Crohn’s Disease Patients After Discontinuation of Vedolizumab or Ustekinumab: The REVEUS Study

: Background/Objectives: In the current era of tailored therapy, biologics such as vedolizumab (VDZ) and ustekinumab (UST) are increasingly administered to inflammatory bowel disease (IBD) patients. The decision to discontinue biologics after side effects or a lack of response is usually simple, but the decision to stop treatment in patients in remission is more difficult: to date, no study has been conducted to investigate the effects of VDZ or UST withdrawal. Our study aims to investigate the rates and predictors of relapse of IBD after the discontinuation of VDZ and UST during a well-controlled disease phase and to evaluate the response to retreatment. Methods: In this observational, multicenter, retrospective study, we included IBD patients who discontinued VDZ or UST during a well-controlled disease phase after at least 1 year of treatment. We collected demographic and clinical data for each patient at the time of discontinuation and at follow-up visits. Results: We included 36 IBD patients from 5 different centers; 80.0%, 58.5%, and 48.3% of patients maintained clinical remission at 12, 24, and 48 months after discontinuation, respectively. Crohn's disease (CD) patients were more likely to maintain remission than ulcerative colitis (UC) patients at 48 months (70.0% vs. 40.0%). No predictors of relapse were identified, but UC patients had a higher risk of early relapse than CD patients (HR = 3.23); 81.3% of retreated IBD patients achieved clinical remission after induction and at 12 months. Conclusions: No predictors of disease relapse after treatment discontinuation were identified. Half of the patients had a relapse within 48 months after discontinuation, but most of them achieved clinical remission after retreatment.