Vedolizumab, a gut-specific monoclonal antibody, renews hope for an alternative to anti-TNF therapy in inflammatory bowel diseases

Recently, GEMINI 1 investigators examined the efficacy of vedolizumab for induction and maintenance of remission in active ulcerative colitis (Mayo score of 6-12 and unsuccessful previous treatment with azathioprine, steroids or biologic therapy) in two integrated randomized controlled trials (RCTs) [1]. In the induction phase, 521 patients received open-label IV vedolizumab 300 mg at weeks 0 and 2 while 374 patients were blinded and randomized to receive vedolizumab or placebo at weeks 0 and 2. Any of these patients who had a response (defined as a 30% and at least 3 score drop from baseline Mayo Clinic Score) to vedolizumab at week 6 were re-randomized to receive placebo or vedolizumab every 4 or 8 weeks up to week 52. At week 6, clinical remission rate was significantly higher in the vedolizumab treatment group (47.1%) compared with patients in the placebo group (25.5%; P<0.001). At week 52, 44.8% of patients who continued to receive vedolizumab every 4 weeks and 41.8% of patients who continued to receive vedolizumab every 8 weeks remained in clinical remission as compared to 15.9% of patients who transitioned to the placebo arm (P<0.001). After one year, more than half of the patients receiving vedolizumab had mucosal healing compared to 20%