OpenBiome begins enrolling patients in first prospective longitudinal safety study for FMT

Press Release


Researchers at nonprofit stool bank begin recruiting participants for study investigating the long-term safety of FMT for treating recurrent C. difficile


Medford, Mass – Researchers at OpenBiome have launched a clinical trial investigating the long-term safety and efficacy of fecal microbiota transplantation (FMT) for treating patients with recurrent Clostridium difficile infection (rCDI) that is not responding to standard antibiotic therapies. Called the STOOL study, this trial is an important step forward for the field as it seeks to provide data-driven evidence to support the long-term safety profile of FMT.

FMT is a procedure in which a stool preparation from a healthy human donor is infused into the colon of a sick patient. It is typically delivered via colonoscopy, enema, or a plastic tube inserted through the nose leading to the intestines. While antibiotics can yield cure rates of less than 40%, FMT has been shown across multiple studies to be 89% effective in treating rCDI. However, studies so far have focused on short-term safety and efficacy outcomes, leaving open questions about the long-term safety profile of a treatment that medical societies advocate as the standard of care for treating rCDI.

The study, titled “Safety of fecal microbiota Transplantation: OpenBiome Outcomes and Longitudinal follow-up for recurrent Clostridium difficile” (STOOL) will be the first to provide long-term safety data for patients who have undergone an FMT for the treatment of rCDI. Dr. Colleen Kelly of Brown Medical Center enrolled the first patients this year, and six other clinical sites are on track to begin recruiting next year. Study collaborators aim to enroll a total of 150 participants, who will be followed for one-year post-FMT procedure.

Adults who have had 3 episodes of C. difficile infections and have not experienced long-lasting clinical resolution following antibiotic therapy are eligible to participate. They will receive an FMT administered by lower delivery, most often by colonoscopy or enema, and then be monitored for one year. At various follow-up points, research staff will contact them to determine if their C.difficile-associated symptoms have resolved, examine their stool microbiome, and assess if they have experienced any negative symptoms or health events that may be attributed to FMT. Beyond long-term safety, the results will also be able to tell if there is a microbial signature that predicts a clinical response, non-response or, if they occur, an adverse event.

“This multi-center, prospective longitudinal study will help inform our collective understanding of the long-term safety of this exciting microbial therapy,” says Dr. Zain Kassam, Chief Medical Officer at OpenBiome. “The body of evidence in this field suggests FMT is a safe intervention and many medical societies advocate for FMT as the standard of care for treating patients with recurrent C. difficile. However, no study has yet rigorously evaluated the long-term safety profile of FMT. We initiated the STOOL study because we believe it will be an important step to validate the promising outcomes clinicians have seen at the patient’s bedside.”


Twitter: @openbiome


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