Oral Capsule or Colonic Fecal Transplant for C. Diff: Is One Superior?

Fecal microbiota transplantation (FMT) delivered via oral capsule or colonic delivery demonstrated similar safety and effectiveness for recurrent Clostridioides difficile infection (CDI) in a prospective study.

In the cohort of 269 patients, no significant differences in 1- and 2-month cure rates were observed between the capsule or colonoscopic FMT groups:

• 1 month: 84% vs 91% (P=0.12)
• 2 months: 81% vs 83% (P=0.70)

Regardless of the route of administration, post-transplant antibiotic use unrelated to CDI was associated with FMT failure, with failure rates of 28% versus 10% for patients who did not receive subsequent antibiotics (P=0.03), reported Byron Vaughn, MD, MS, of the University of Minnesota in Minneapolis, and colleagues.

“Attention should be given to patient selection based on subsequent likelihood of antibiotic requirement,” the group wrote in Clinical Gastroenterology and Hepatology. “If a patient seems likely to require a repeat course of antibiotics, then extending oral vancomycin administration or considering bezlotoxumab may be effective alternatives.”

On multivariate analysis, other factors significantly linked to a greater risk of FMT failure included age 65 or older (OR 2.6, 95% CI 1.2-5.9) and need for dialysis (OR 9.4, 95% CI 2.0-43.8).

Vaughn’s group noted that the widespread adoption of FMT in clinical practice, which is backed by guidelines, has been driven by the increased incidence of recurrent CDI in patients who fail standard antibiotics.

“Unlike antibiotic treatments, which perpetuate and worsen the intestinal dysbiosis, FMT restores the host microbiota diversity and function, effectively breaking the cycle” of recurrent CDI, the group explained.

“Treatment with oral capsules offers advantages of ease of delivery, lack of a bowel purgative, and absence of colonoscopy associated risks,” they noted. “In contrast, colonoscopic administration delivers the microbiota into its intended compartment in the intestine and enables diagnostic evaluation of the colonic mucosa.”

But safety and efficacy has varied with different routes of administration, and prior trials have largely excluded patients with multiple comorbidities.

For their study, Vaughn and colleagues examined data from the American Gastroenterological Association FMT national patient registry. Across six centers from July 2019 to October 2021, a total of 269 patients with recurrent CDI received capsule (n=170) or colonoscopic FMT (n=96) formulations manufactured by the University of Minnesota Microbiota Therapeutics Program (MTP).

Route of administration was determined by the treating physician, and the FMT formulations consisted of either oral, freeze-dried capsules (MTP-101C) or a frozen-thawed liquid suspension that had been preserved with glycerol for colonoscopy delivery (MTP-101LR).

Recurrent CDI cure rates in the overall population were 86% (95% CI 82-90) at 1 month and 81% (95% CI 75-86) at 2 months. Of the patients with recurrences following the first FMT, 41% had repeat procedures (range 2-4), and the cure rate in this subset was 82% at 2 months.

Adverse events were similar among groups, and consistent with other reports, the study authors noted. Changes in bowel function were common, including diarrhea (29% at 1 week), constipation (12%), gas (22%), and bloating (15%). However, Vaughn and colleagues noted that gastrointestinal symptoms related to FMT are difficult to differentiate from those of recurrent CDI.

Only one serious adverse event of aspiration pneumonia related to colonoscopy occurred, but no other new safety signals were reported. One patient died from natural causes in the capsule FMT group.

The vast majority of patients were white, and 72% were women. Overall, 38% had been hospitalized for CDI, and 88% had two or more episodes of recurrent CDI in the prior year.

Patients in the capsule FMT group tended to be older (median 68 vs 54 years), but less likely to have inflammatory bowel disease (9.4% vs 18%) or immunosuppression (18% vs 30%) than those in the colonoscopic group.

Limitations to the data included that route of administration may be prone to selection bias. Additionally, because of the risk of infectious disease transmission, FMT requires rigorous donor screening, and multistep lab testing could have affected recurrence rates.