An open-label evaluation of rifaximin in the treatment of active Crohn's disease.

OBJECTIVE

This open-label study was conducted as a preliminary assessment of rifaximin (200 mg TID for 16 weeks) for the treatment of active Crohn's disease in patients (n = 29) with symptoms for at least 3 months before screening and a Crohn's Disease Activity Index (CDAI) score > 220 and < 400.

RESULTS

At the end of month 4, mean +/- CDAI score was reduced by 43% compared with baseline in the intent-to-treat population (n = 29; baseline = 278 +/- 51; month 4 = 159 +/- 102; p < 0.0001 month 4 versus baseline). A similar pattern of results was observed in the per-protocol population (i.e., patients at least 70% compliant with the treatment regimen and having no protocol violations thought to affect efficacy results; n = 16), in which mean CDAI scores at month 4 were reduced by 41% from a baseline of 262.9 +/- 38.2 to 155.6 +/- 104.5 (p = 0.0009 month 4 versus baseline). Fifty-nine percent of patients (59%) had a > or = 70-point improvement in CDAI score beginning with the first assessment at the end of month 1. By the end of the treatment period, 78% of patients had a > or = 70-point improvement in CDAI score. Clinical remission, defined as CDAI score < 150, was observed at the end of treatment months 1, 2, 3, and 4 in 41%, 56%, 56%, and 59% of patients, respectively. Twenty-three (23) patients completed the 4-month course of rifaximin therapy, and 6 prematurely withdrew. The most common adverse events were abdominal pain, fatigue, and headache.

CONCLUSION

These data, which are consistent with the possibility that rifaximin may be useful for active Crohn's disease, warrant confirmation in a randomized, double-blind, placebo-controlled trial.