Entyvio lengthen dose-interval study: lengthening vedolizumab dose interval and the risk of clinical relapse in inflammatory bowel disease.

BackgroundVedolizumab (VDZ), an 47 anti-integrin antibody, is efficacious in the induction and maintenance of remission in ulcerative colitis (UC) and Crohn's disease (CD). In the GEMINI long-term safety study, enrolled patients received 4-weekly VDZ. Upon completion, patients were switched to 8-weekly VDZ in Australia. The clinical success rate of treatment de-escalation for patients in remission on VDZ has not been described previously.AimTo determine the proportion of patients who relapsed after switching from 4 to 8-weekly VDZ, the mean time to relapse, and the recapture rate when switching back to 8-weekly dosing.Materials and methodsThis was a retrospective, observational, multicenter study of patients previously recruited into GEMINI long-term safety in Australia. Data on the demographics and biochemical findings were collected.ResultsThere were 34 patients [23 men, mean age 49.1 (13.1) years] and their mean disease duration was 17.6 (+/- 8.5) years. The mean 4-weekly VDZ infusion duration was 286.5 (+/- 48.8) weeks. A total of five (15%) patients relapsed on dose-interval increase (4/17 UC, 1/17 CD) at a median duration from dose interval lengthening to flare of 14 weeks (interquartile range=6-25). Eighty percent (4/5) of patients re-entered remission following dose-interval decrease back to 4-weekly. No clinical predictors of relapse could be determined because of the small cohort size.ConclusionThe risk of patients relapsing when switching from 4 to 8-weekly VDZ approximate to 15% and is similar between CD and UC. Dose-interval decrease recaptures 80% of patients who relapsed. Therapeutic drug monitoring of VDZ may be of clinical relevance.