By Stan Deresinski, MD, FACP, FIDSA

Clinical Professor of Medicine, Stanford University

Dr. Deresinski reports no financial relationships relevant to this field of study.

SYNOPSIS: Fecal microbiota transplantation orally administered in capsules was non-inferior to administration by colonoscopy.

SOURCE: Kao D, Roach B, Silva M, et al. Effect of oral capsule- vs colonoscopy-delivered fecal microbiota transplantation on recurrent Clostridium difficile infection: A randomized clinical trial. JAMA 2017;318:1985-1993.

In an unblinded, randomized, non-inferiority trial at three academic medical centers in Alberta, Canada, Kao and colleagues examined the relative efficacy of fecal microbiota transplantation (FMT) by colonoscopy or by orally administered capsules in prevention of recurrence of Clostridium difficile infection (CDI). The mean age of the 116 randomized (1:1) patients was 58 years. Two-thirds of the patients were women.

All patients were treated initially with oral vancomycin 125 mg four times daily for at least 10 days and until symptom resolution, followed by 125 mg twice daily, with discontinuation 24 hours before FMT. Patients were not allowed to take proton pump inhibitors. All patients ingested 4 liters of propylene glycol on the night prior to FMT. For patients randomized to colonoscopy, 360 mL of fecal slurry was delivered to the cecum, while those in the comparator group ingested 40 capsules containing fecal slurry. The slurry was prepared from stool provided by seven healthy volunteers.

The results of the two methods of treatment admin-istration were identical with regard to the primary endpoint of prevention of recurrence at 12 weeks after a single FMT: 51/53 (96.2%) and 50/52 (96.2%) in the capsule and the colonoscopy groups, respectively. Both methods were tolerated; non-serious adverse events occurred in 5.4% and 12.5%, respectively.

COMMENTARY

The authors point out that the success rates in this study were higher than previously reported. They suggest that this may be the consequence of at least two factors the fecal dose and the intestinal washout. Thus, the amount of feces delivered in this study was greater than that in others. Vancomycin persists in the fecal stream for as long as eight days after completion of a course of oral administration, and the intestinal washout can be hypothesized to remove residual vancomycin, the persistence of which would adversely affect the fecal microbiota.

This study is valuable because it demonstrates that previous studies that found somewhat better outcomes with FMT by colonoscopy than via the upper gastrointestinal tract may not be correct. The ability to avoid colonoscopy makes the overall cost of FMT significantly lower and, with the commercial availability of orally administered transplant material (although not studied here), makes FMT more widely available. How this approach fares when compared to others, such as the use of fidaxomicin and vancomycin tapers, remains to be determined in additional randomized trials.