OP33 Results of a randomised controlled trial to evaluate Interleukin 1 blockade with anakinra in patients with acute severe ulcerative colitis (IASO)

Abstract Background Acute severe ulcerative colitis (ASUC) is a manifestation of (UC) that requires hospitalisation. Despite significant advances in therapeutic options for UC and the medical management steroid-refractory ASUC, initial treatment paradigm ASUC has not changed since 1950s based on use intravenous (IV) corticosteroids. Approximately 50% patients do respond require further or surgical therapy. Interleukin 1 (IL-1) been identified as key mediator colonic inflammation plays pivotal role local activation neutrophils number downstream inflammatory mediators. The IL-1 axis repeatedly target UC. blockade Severe Colitis (IASO) trial investigated whether antagonism signalling could improve outcomes with ASUC. Methods We performed phase II, multicentre randomised (1:1), placebo-controlled, double-blinded short-duration anakinra, given alongside IV corticosteroids to adult hospitalised suspected confirmed primary outcome was incidence (ie infliximab/ciclosporin) rescue therapy (colectomy) within 10 days following commencement corticosteroid Secondary included disease activity, time clinical response, therapy, colectomy by day 98 post safety. aimed recruit 214 across 20 sites UK. Prespecified analyses were feasibility futility. Results At prespecified interim futility analysis, 113 had randomised, 55 placebo, 58 anakinra (figure 1). higher group than placebo (43% vs 26%). (11% 4%). These differences statistically significant. Logistic models containing mixture baseline stratification factors did suggest need would be reduced advice independent data monitoring committee, terminated There adverse event group, most common worsening colitis. Conclusion This shows adding current standard care reduce colectomy. suggests no safety concerns treatment.