Vowst is the first and only FDA-approved orally administered microbiota-based therapeutic for the prevention of recurrent C. diff infection in adults.
The US Food and Drug Administration (FDA) has approved Vowst™ (SER-109, Seres Therapeutics, Inc.), the first orally administered fecal microbiota product indicated for the prevention of recurrent Clostridioides difficile infection (CDI) in adults following antibacterial treatment.
“Today’s approval provides patients and healthcare providers a new way to help prevent recurrent C. difficile infection,” said Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, in a press release. “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.”
Vowst is manufactured from human fecal matter collected from qualified donors and contains live bacteria. The approved dosing regimen for Vowst includes 4 capsules taken orally once daily for 3 consecutive days, according to the agency’s release.
“Recurrent C. difficile infection is a highly debilitating and life-threatening disease, and antibiotics alone do not address the underlying cause of rCDI, dysbiosis of the gut microbiome,” said Carl Crawford MD, assistant professor of clinical medicine at Weill Cornell Medical College, in a Seres Therapeutics press release. “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 to recurrent CDI patients.”
The FDA based its approval on safety results from a randomized, double-blind, placebo-controlled study, as well as an open-label clinical trial conducted in the US and Canada. Included participants had recurrent CDI and been administered antibacterial treatment 48 to 96 hours before, with controlled symptoms. Across both studies, 346 patients aged ≥18 years with recurrent CDI received all scheduled doses of Vowst.
In an additional analysis of 90 persons who received Vowst compared with 92 individuals who received placebo, the most common adverse events included abdominal bloating, fatigue, constipation, chills, and diarrhea.
The efficacy of Vowst was assessed in a randomized, placebo-controlled study, in which 89 patients received Vowst and 93 participants received placebo. Through 8 weeks after treatment, CDI recurrence in the Vowst arm was lower compared to the placebo group (12.4% vs 39.8%).
The FDA stated that Vowst may contain food allergens, and it remains unknown whether there is potential for adverse reactions associated with food allergens. There is a risk that Vowst may carry transmissible infectious agents, although the donors and donated stool are tested for a panel of transmissible pathogens, noted the agency.
“Recurrent C. difficile infection significantly impacts patients’ quality of life, both physically and emotionally, leaving many living in tremendous fear of future recurrences. Patients have been waiting for new treatment options that address a key concern: prevention of an additional CDI recurrence,” said Christian John Lillis, executive director at Peggy Lillis Foundation for C. diff Education and Advocacy, in the Seres Therapeutics release.