First Live Microbiota Treatment for Recurrent CDI Wins FDA Approval

The US Food and Drug Administration (FDA) on November 30, 2022, approved RBX2660 (Rebyota) the first-ever microbiota-based live biotherapeutic indicated for the prevention of recurrent Clostridioides difficile infections (rCDI) in adult patients who have completed a course of antibiotic treatment for rCDI.

The novel treatment, developed by Ferring Pharmaceuticals, is prepared from stool donated by qualified healthy individuals, and comes as a prepackaged single dose that is administered rectally.

“We believe this is a major breakthrough in harnessing the power of the human microbiome to address significant unmet medical needs,” Per Falk, president of Ferring, said in a news release. Beyond the milestone the approval represents for persons living with rCDI, says Falk, it “presents a significant step which holds promise that many other diseases might be better understood, diagnosed, prevented and treated using our rapidly evolving insights.”

The approval is based on results from Ferring’s clinical program that included the randomized, double-blind, placebo-controlled phase 3 PUNCH CD3 trial. Treatment of 262 patients was blinded (n=177, REBYOTA; n=85, placebo) and the key primary endpoint was treatment success, defined by investigators as the absence of CDI diarrhea within 8 weeks post-study treatment.

Using Bayesian model estimates the study found statistically higher treatment success among patients treated with RBX2660 (70.6%) than among placebo-treated participants (57.5%). Posterior probability was 99.1% that RBX2660 was superior to placebo in reducing rCDI following standard-of-care antibiotic treatment.

Moreover, when assessed at 6 months after completing treatment, more than 90% of study participants who had achieved treatment success had not experienced rCDI, according to Ferring.

Across safety studies, adverse events were primarily mild-to-moderate, and the investigators reported no treatment-related serious adverse events. Adverse events related to treatment were more frequent among those who received RBX2660 vs placebo (55.6% vs 44.8%) according to Ferring and were driven primarily by a higher incidence of mild gastrointestinal events.

"Today's approval of Rebyota is an advance in caring for patients who have recurrent C. difficile infection," said Peter Marks, MD, PhD, director of the FDA's Center for Biologics Evaluation and Research, in an agency statement. 

"Recurrent CDI impacts an individual's quality of life and can also potentially be life-threatening. As the first FDA-approved fecal microbiota product, today's action represents an important milestone, as it provides an additional approved option to prevent recurrent CDI."