Probiotic Treatment of Ulcerative Colitis with Trichuris Suis Ova: A Randomised, Double-blinded, Placebo-controlled Clinical Trial [the PROCTO Trial]

Abstract

Background and Aims: To demonstrate that administration of 7500 Trichuris suis ova [TSO] every second week over 24 weeks would reduce the intestinal inflammation in moderate ulcerative colitis. Methods: A single-centre, randomised, double-blinded, placebo-controlled, phase 2b clinical trial of 7500 Trichuris suis ova every 2 weeks for 24 weeks compared with placebo in moderate activity of ulcerative colitis [Mayo score 6-10] were performed. Primary outcome: clinical remission; secondary outcomes: clinical response at 24 weeks, complete corticosteroid-free clinical remission, endoscopic remission, symptomatic remission at 12 and 24 weeks, and partial Mayo score over time. Results: In all, 119 patients were randomised to Trichuris suis ova [na=a60] or placebo [na=a59]. At Week 24, clinical remission was achieved in 30% of Trichuris suis ova-Treated vs 34% of placebo-Treated (risk ratio [RR]a=a0.89; 95% confidence interval [CI]: 0.52-1.50; pa=a0.80, intention to treat). No difference was found in clinical response in any of the clinical response subgroups. However, in patients who did not need treatment with corticosteroids during the trial, a temporary effect of TSO was seen in the analysis of symptomatic remission at Week 12 [pa=a0.01] and the partial Mayo score at Week 14 and Week 18 [pa