FMT Passes First Randomized Placebo-Controlled Trial for Treating C. Diff Infection

The results from the first randomized placebo-controlled trial of fecal microbiota transplant (FMT) in treating recurrent Clostridium difficile infection showed the procedure was 91% effective in preventing recurrence for at least eight weeks.

Reporting at the American College of Gastroenterology Scientific Meeting in Honolulu, Colleen Kelly, MD, of Brown University in Providence, RI, and colleagues in Providence and at Montefiore Medical Center in the Bronx, NY, said that the cure rate was significantly higher than in patients who got a placebo treatment.

But for reasons researchers were unable to determine, the placebo group (made up of patients who were unknowingly transplanted with their own stool) was also 63% cured. Patients received vancomycin before FMT so it is possible they were already free of C.diff before being enrolled in the study.

Regardless, the 91% success of the treatment was impressive, Kelly said.

One of the limitations of the trial was its small size. Only 46 patients participated. Also, half were in the Bronx and half in Rhode Island so they may have had differences in demographic-related traits that had an impact on the results.

The results appeared not to surprise anyone, since much has been written about the procedure and its often dramatic impact on patients who had seemingly intractable infections.

FMT was discussed in many contexts at the meeting, as it was at IDWeek in San Diego, CA, held earlier this month. There, infectious disease doctors noted that some patients were already doing FMT in their homes using makeshift equipment, including blenders and French-press coffee makers. Do-it-yourself videos are available on youtube.

At the ACG meeting, much discussion focused on the technical aspects of the procedure for use by clinicians, developments in commercially available stool, and promising work on FMT capsules that could make the procedure easier, cleaner and more acceptable to those who find it distasteful or intimidating.

The first FMTs were usually done with unscreened donor stool, often from a patient’s close relative.

Kelly’s study used donor stool from people who were screened for behaviors that might increase the chances their stool would contain something harmful to the recipient. That practice is giving way to purchasing frozen stool from paid donors that it tested for pathogens from paid donors who are also screened for things such as antibiotic use. Open Biome, a Massachusetts non-profit, is the main provider of the product.

The FDA allows the practice if done under a research protocol.

Kelly said she is staunch supporter of FMT. “It’s changed my life,” she said.