One Year Study of Rifaximin Delayed Release (DR) in Crohn's Disease

A Double-Blind, Placebo-Controlled, Parallel-Group, Multicenter, Multiregional, One Year Study to Assess the Efficacy and Safety of Twice Daily Oral Rifaximin Delayed Release Tablets for Induction of Clinical Remission With Endoscopic Response at 16 Weeks Followed by Clinical and Endoscopic Remission at 52 Weeks in Subjects With Active Moderate Crohn's Disease

The primary objective is to determine the efficacy of rifaximin DR also referred to as Extended Intestinal Release (EIR) tablets vs. placebo for the induction of clinical remission and endoscopic response following 16 weeks of treatment in participants presenting with active moderate Crohn's disease. A key secondary objective is to evaluate clinical and endoscopic remission following an additional 36 weeks of treatment.

RECD3126 is a double-blind, placebo-controlled, parallel-group, multicenter, multiregional, 52-week study to assess the efficacy and safety of rifaximin DR tablets for the induction of clinical remission and endoscopic response at 16 weeks followed by clinical and endoscopic remission after 52 weeks of continuous therapy in participants with active moderate Crohn's disease.

Participants will be randomized in a 1:1 allocation to rifaximin or placebo at the beginning of the treatment period and will maintain treatment assignment throughout the duration of the study. Ileocolonoscopy will be performed on all participants at baseline, between Weeks 16 and 17 (end of the Induction Phase), and following completion of the 36-week Long Term Treatment Phase (Week 52).

Major Inclusion Criteria:

• Moderate, non-fistulizing Crohn's disease in the ileum and/or colon prior to randomization; and a SES-CD score of ≥7 (confirmed by centralized endoscopy reading).
• During the screening period, the participant will need to have certain average daily scores for abdominal pain and average number of liquid/very soft stools.

Major Exclusion Criteria:

• Pregnant or lactating females. Females of childbearing (reproductive) potential must have a negative serum pregnancy test at screening and agree to use a highly effective method(s) of contraception throughout their participation in the study. Diagnosis of ulcerative or indeterminate colitis.
• Diagnosis of Celiac Disease.
• Bowel surgery within 12 weeks prior to screening and/or has surgery planned or deemed likely for Crohn's disease during the study period.
• Presence of an ileostomy or colostomy.
• Known fixed symptomatic stenosis/stricture of the small or large bowel.
• Had more than one segmental colonic resection.
• Had more than 3 small bowel resections or symptoms associated with short bowel syndrome.
• Current evidence of peritonitis.
• History or evidence of colonic mucosal dysplasia.
• History or evidence of adenomatous colonic polyps that have not been removed.
• Unwilling to be tapered off corticosteroids by Week 8 or the participant is known by the Investigator to be steroid-dependent.
• Has used a biologic within 12 weeks of randomization.
• Used cyclosporine, tacrolimus, sirolimus, mycophenolate mofetil, or similar drugs within 8 weeks prior to randomization.
• Had rectal administration of 5-aminosalicylic acid (5-ASA) or corticosteroid enemas/foams/ suppositories within 2 weeks prior to screening visit.