Reduced Recurrent C difficile Infection Risk in Patients Treated With Investigational Oral Microbiome

Clostridium difficile
Clostridium difficile, c difficile
Researchers assessed the effects of engraftment on recurrent Clostridioides difficile infection.

The following article is a part of conference coverage from the American College of Gastroenterology 2021 Annual Meeting , held from October 22 to 27, 2021. The team at Gastroenterology Advisor will be reporting on the latest news and research conducted by leading experts in gastroenterology. Check back for more from ACG 2021.


Patients treated with the investigational oral microbiome CP101 had a lower risk for recurrent Clostridioides difficile infection (CDI) compared with patients who received placebo, according to research presented at the American College of Gastroenterology (ACG) 2021 Annual Meeting, held from October 22 to 27, 2021, in Las Vegas, Nevada and virtually.

The randomized, double-blind PRISM3 trial ( Identifier: NCT03110133) included 198 patients who previously had more than one recurrence of CDI or who had at least one recurrence of CDI and were considered high risk for additional recurrences. Patients were assigned to CP101 or placebo at a 1:1 ratio. After completing the appropriate antibiotics for CDI treatment, all patients underwent a 2-day wash out period before receiving a one-time oral dose of CP101 or placebo.

The primary endpoint was the absence of CDI recurrence through 8 weeks after intervention. No recurrence after 8 weeks was deemed a clinical cure. The secondary endpoint assessed engraftment, the presence of administered microbiomes in the gastrointestinal tract.

Patients who received CP101 had a significantly higher rate of clinical cure (74.5%) compared with patients who received placebo (61.5%). Engraftment of CP101 microbiomes was strongly correlated with clinical cure, as 96% of patients with successful engraftment did not have CDI recurrence.

Investigators note that additional research is needed to optimize successful engraftment to reduce CDI recurrence.

Disclosure: Some author(s) declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

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Allegretti J, Kelly C, Louie T, et al. CP101 engraftment drives efficacy: results from a randomized, placebo-controlled trial evaluating CP101, an investigational orally administered microbiome therapeutic for prevention of recurrent C. difficile infection. Presented at: ACG 2021 Annual Meeting; October 22-27, 2021; Las Vegas, NV and virtual. Abstract P0129.