Fecal Transplants Bring Hope to Patients, Challenge the FDA

Janis C. Kelly


December 15, 2014

In This Article

Industry Takes Notice

At the same time as clinical acceptance took hold, researchers began to seek alternatives to the admittedly unaesthetic home-blender enema FMT. These included manufactured FMT products, stool banks, use of frozen rather than fresh stool, and biosynthetic alternatives.

Rebiotix, Inc., developed RBX2660, a standardized "microbiota suspension" derived from fresh stool, which received fast-track status from the FDA. Researchers led by Erik Dubberke, MD, from the Division of Infectious Diseases at Washington University School of Medicine in St Louis, Missouri, reported phase 2 safety data in early October 2014, showing no serious treatment-related adverse events and an overall efficacy rate of 87.1%.[13]

Clinicians who want to perform FMT without the hassle of preparing stool can turn to a nonprofit stool bank, such as OpenBiome. Dr Kelly said, "OpenBiome has shown that they can provide material to a large number of clinicians and researchers at a reasonable cost ($250 per dose). This is very advantageous for patients, who may not be able to identify a suitable donor or who may end up reimbursing their donors for laboratory testing that is not always covered, and for physicians, who may spend hours on the donor identification/screening process.

"OpenBiome is arguably safer as well," Dr Kelly continued. "They monitor donors carefully at and between donations, quarantine all material for 30 days until donors can be rescreened, and preserve safety aliquots on all material."

Other institutions are setting up their own stool banks. Herbert L. DuPont, MD, director of the Center for Infectious Diseases at the University of Texas Health Science Center in Houston, Texas, who is helping set up a bacteriotherapy or FMT service for two hospitals at the Texas Medical Center, advised physicians to work with the blood-banking facilities at their hospitals to set up donor screening and sample storage.[2]

Ilan Youngster, MD, from the Division of Pediatric Infectious Diseases, Boston Children's Hospital and Massachusetts General Hospital in Boston, and colleagues[14] reported that frozen capsules prepared from the stool of healthy donors produced complete resolution of diarrhea in 70% of 20 patients with CDI after a single 15-capsule treatment and in 90% after a second treatment.[14]

Dr Youngster said, "With the caveat of this being a small study, it seems as if oral administration of frozen fecal capsules is well tolerated, safe, and has success rates comparable to other modes of administration of FMT. Since the study was published, we have treated another 20 patients, with similar results."

The need to harvest, test, and prepare stool from donors for FMT would be obviated if the key organisms in stool could be identified, cultured, and packaged in a synthetic form. Drs Petrof and Allen-Vercoe have developed and hold the patent on "RePOOPulating" the gut. Their proof-of-principle study in three patients with recurrent C difficile in whom at least three courses of metronidazole or vancomycin had failed showed that all were symptom-free within 2-3 days after receiving RePOOPulate via colonoscopy and remained so for 6 months thereafter.[15]

According to the patent application, the synthetic stool preparation comprises a mixture of bacterial strains isolated and purified from a healthy donor who had not received antibiotics in the past 5 years. Strains known to be pathogenic, to have an unfavorable antibiotic resistance profile resistant to imipenem or vancomycin (or both), and those considered difficult to culture or that grow unreliably were not included.[16]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: