Combined budesonide and antibiotic therapy for active Crohn's disease: a randomized controlled trial

Although antibiotics are frequently used to treat Crohn's disease, this practice is not supported by strong evidence from randomized trials.

We conducted a double-blind multicenter study of patients with active Crohn's disease of the ileum, right colon, or both. Patients were randomized to receive oral ciprofloxacin and metronidazole, both 500 mg twice daily, or placebo for 8 weeks. All patients received oral budesonide 9 mg once daily. The primary efficacy measure was the proportion of patients in remission at week 8.

Of the 134 patients who were randomized, 130 were evaluated for efficacy; 66 received placebo, and 64 received antibiotics. At week 8, 21 patients (33%) assigned to antibiotics were in remission as compared with 25 patients (38%) in the placebo group (P = 0.55; absolute difference, -5%; 95% confidence interval, -21% to 11%). An interaction (P = 0.025) between treatment allocation and disease location on treatment response was identified. Among patients with disease of the colon, 9 of 17 (53%) were in remission after treatment with antibiotics, compared with 4 of 16 (25%) of those who received placebo (P = 0.10). Discontinuation of therapy because of adverse events occurred in 13 of 66 (20%) patients treated with antibiotics, compared with 0 of 68 in the group who received placebo (P < 0.001).

In patients with active Crohn's disease of the ileum, the addition of ciprofloxacin and metronidazole to budesonide is an ineffective intervention, but this antibiotic combination may improve outcome when there is involvement of the colon.