Microbiota Restoration Therapy for Recurrent Clostridium Difficile Infection


About this study

This is the first prospective, multi-center, double-blinded, randomized controlled study of a microbiota suspension derived from intestinal microbes. Patients who have had at least two recurrences of C. difficile infection (CDI) after a primary episode and have completed at least two rounds of standard-of-care oral antibiotic therapy or have had at least two episodes of severe CDI resulting in hospitalization may be eligible for the study. Patients whose CDI returns in less than 8 weeks after the last assigned study treatment may be eligible to receive up to 2 treatments with RBX2660 in the open-label portion of the study.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • ≥ 18 years
  • Medical record documentation of recurrent CDI either: a) at least two recurrences after a primary episode and has completed at least two rounds of standard-of-care oral antibiotic therapy or b) has had at least two episodes of severe CDI resulting in hospitalization.
  • Documented history that the subject's recurrent CDI is controlled while on antibiotics even if the subject is not currently on antibiotics.
  • A positive stool test for the presence of C. difficile within 60 days prior to enrollment.

Exclusion Criteria:

  • A known history of continued C. difficile diarrhea while taking on a course of antibiotics prescribed for CDI treatment.
  • Requires antibiotic therapy for a condition other than recurrent CDI.
  • Previous fecal transplant prior to study enrollment.
  • History of inflammatory bowel disease (IBD), e.g., ulcerative colitis, Crohn's disease, or microscopic colitis.
  • History of irritable bowel syndrome (IBS).
  • History of chronic diarrhea.
  • History of celiac disease.
  • Colostomy.
  • Planned surgery requiring perioperative antibiotics within 6 months of study enrollment.
  • Life expectancy of < 12 months.
  • Compromised immune system.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Scottsdale/Phoenix, Ariz.

Mayo Clinic principal investigator

Robert Orenstein, D.O.

Closed for enrollment

More information


  • Recurrent Clostridium difficile infection is difficult to treat, and failure rates for antibiotic therapy are high. We studied the effect of duodenal infusion of donor feces in patients with recurrent C. difficile infection. Read More on PubMed
  • Clostridium difficile infection (CDI) is a gastrointestinal disease believed to be causally related to perturbations to the intestinal microbiota. When standard treatment has failed, intestinal microbiota transplantation (IMT) is an alternative therapy for patients with CDI. IMT involves infusing intestinal microorganisms (in a suspension of healthy donor stool) into the intestine of a sick patient to restore the microbiota. However, protocols and reported efficacy for IMT vary. We conducted a systematic literature review of IMT treatment for recurrent CDI and pseudomembranous colitis. In 317 patients treated across 27 case series and reports, IMT was highly effective, showing disease resolution in 92% of cases. Effectiveness varied by route of instillation, relationship to stool donor, volume of IMT given, and treatment before infusion. Death and adverse events were uncommon. These findings can guide physicians interested in implementing the procedure until better designed studies are conducted to confirm best practices. Read More on PubMed

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