Efficacy of vedolizumab with and without continued immunosuppressant use in gemini 1 and gemini 2

Introduction In GEMINI 1 and GEMINI 2, vedolizumab (VDZ) was safe and effective in patients (pts) with ulcerative colitis (UC) or Crohn's disease (CD), respectively, on stable doses of immunosuppressants (IS).1,2 The effect of discontinuing IS in pts who responded to VDZ induction therapy in these studies has not been characterised. Methods Pts who responded to VDZ at week (wk) 6 were rerandomised to placebo (VDZ/PBO) or VDZ every 4 or 8 wks (VDZ/VDZ Q4W or Q8W) for 46 wks. At United States (US) sites, re-randomised pts discontinued IS use at wk 6. At non- US sites, pts could continue IS use. Efficacy, VDZ serum concentration, and immunogenicity data (via an enzyme-linked immunosorbent assay) were evaluated post hoc in pts with baseline IS use stratified by region. Results At wk 52, rates of clinical remission and response (Table), mucosal healing (UC), durable clinical remission, and corticosteroid-free remission were numerically higher with VDZ, mostly irrespective of IS use. The US and non-US sites had similar numbers of patients who were positive for anti- VDZ antibodies during VD maintenance therapy (Table). Mean trough concentrations were similar between US and non- US pts at wk 46. [TABLE PRESENTED] Conclusion Discontinuing IS did not appear to substantially affect efficacy of VDZ maintenance therapy. Interpretation of these post hoc analyses is limited by potential IS discontinuation in non-US pts and the relatively small sample sizes.