FDA OKs First Poop-Based Oral Therapy

— Vowst approved for preventing recurrent C. difficile infections after antibiotics

MedicalToday
FDA APPROVED Vowst over a microscope image of C. difficile bacteria.

The FDA approved the for preventing recurrent Clostridioides difficile infections in adults, the agency announced on Wednesday.

Developed as SER-109 and given the trade name of Vowst, the therapy is indicated for patients who have already received a course of antibiotics for recurrent C. difficile infections.

SER-109 -- which involves four pills taken once a day for 3 consecutive days -- contains live bacteria from donor fecal matter, with the donors and stool screened for a slew of pathogens. Despite that, the agency still warns that the product carries the potential risk of transmitting infectious agents or food allergens.

"Today's approval provides patients and healthcare providers a new way to help prevent recurrent C. difficile infection," Peter Marks, MD, PhD, director of the FDA's Center for Biologics Evaluation and Research, said in a statement. "The availability of a fecal microbiota product that can be taken orally is a significant step forward in advancing patient care and accessibility for individuals who have experienced this disease that can be potentially life-threatening."

Approval was supported by the randomized ECOSPOR III trial and an conducted in the U.S. and Canada.

In ECOSPOR III, which involved 182 patients with recurrent infections but with symptoms under control following a course of antibiotics, patients assigned to SER-109 had significantly lower recurrence rates of C. difficile infection through 8 weeks compared with those assigned to placebo (12.4% vs 39.8%, P<0.001).

Results were consistent across age groups and largely held up at 24 weeks, at 21.3% in the SER-109 group and 47.3% for the placebo group.

C. difficile infections can cause a host of symptoms (diarrhea, abdominal pain, fever) and organ failure or death in severe cases. One of the most common healthcare-associated infections, these infections are linked with anywhere from 15,000 to 30,000 deaths each year.

While standard treatment involves antibiotics, these can alter the microbiome and allow C. difficile to return, and few treatments exist for recurrent infections, which are more likely to affect immunocompromised individuals, people over 65, and those who are hospitalized or living in nursing homes.

"Recurrent C. difficile infection is a highly debilitating and life-threatening disease," said Carl Crawford, MD, of Weill Cornell Medical College in New York City, in a from developer Seres Therapeutics, adding that antibiotics alone do not address the underlying cause of recurrent infections -- "dysbiosis of the gut microbiome."

Fecal microbiota products are thought to restore the gut flora, thereby helping prevent further infections. In December, the FDA approved Rebyota as the first such product for preventing recurrence of C. difficile infections, though Rebyota needs to be administered rectally.

"The approval of Vowst provides an important new oral treatment option for this disease, and I am pleased to now be able to offer this medicine," Crawford added.

In trials, the most commonly reported side effects with SER-109 that occurred at a rate higher than with placebo included abdominal bloating, fatigue, constipation, chills, and diarrhea, the FDA noted.

Seres said it expects the product to be available by June.

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    Ian Ingram is Managing Editor at and helps cover oncology for the site.