Ornidazole for prophylaxis of postoperative Crohn's disease recurrence: A randomized, double-blind, placebo-controlled trial

Background & Aims: Crohn's disease almost inevitably recurs after ileocolonic resection, and effective prophylactic therapy has not been identified. We investigated the efficacy and safety of ornidazole, a nitroimidazole antibiotic, for the prevention of clinical recurrence of Crohn's disease after curative ileocolonic resection in a placebo-controlled double-blind clinical trial. Methods: Eighty patients were randomized to ornidazole 1 g/day or placebo started within 1 week of resection and continued for 1 year. The primary end point was the proportion of patients with clinical recurrence at 1 year. Secondary end points were endoscopic recurrence at 3 months and 12 months after resection. Results: Two patients in the ornidazole group withdrew consent and were not dosed. Ornidazole significantly reduced the clinical recurrence rate at 1 year from 15 of 40 (37.5%) patients in the placebo group to 3 of 38 (7.9%) patients in the ornidazole group (Fisher exact test, 8.03; P = .0046; odds ratio, 0.14; 95% confidence interval, 0.037-0.546). Ornidazole reduced endoscopic recurrence at 12 months from 26 of 33 (79%) in the placebo group to 15 of 28 (53.6%) in the ornidazole group (χ2, 4.37; P = .037; odds ratio, 0.31; 95% confidence interval, 0.10-0.94). Endoscopic recurrence at 3 and 12 months predicted clinical recurrence. Significantly more patients in the ornidazole group dropped out from the study because of side effects (P = .041). Conclusions: Ornidazole 1 g/day is effective for the prevention of recurrence of Crohn's disease after ileocolonic resection.