Today's Clinical Lab - News, Editorial and Products for the Clinical Laboratory
3D illustration of bacteria inside the large intestine.
C. difficile infection is one of the most common healthcare-associated infections whose symptoms include diarrhea, abdominal pain, fever, and in some cases, organ failure and death.
iStock, ChrisChrisW

FDA Approves First Orally Administered Fecal Microbiota Product to Prevent CDI Relapse

Fecal microbiota may aid in the restoration of the gut flora to prevent the recurrence of CDI

U.S. Food and Drug Administration
Published:Apr 28, 2023
|2 min read
Register for free to listen to this article
Listen with Speechify

The U.S. Food and Drug Administration approved Vowst, the first fecal microbiota product that is taken orally. Vowst is approved for the prevention of recurrence of Clostridioides difficile (C. difficile) infection (CDI) in individuals 18 years of age and older, following antibacterial treatment for recurrent CDI. 

“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. “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.”

C. difficile infection: Etiology, risk factors, treatment options

CDI, caused by the bacterium C. difficile, is one of the most common healthcare-associated infections in the United States and is associated with 15,000 to 30,000 deaths annually. The human intestinal tract contains millions of microorganisms, often referred to as the “gut flora," or "gut microbiome." Certain situations, such as taking antibiotics to treat an infection, may change the balance of microorganisms in the gut, allowing C. difficile to multiply and release toxins causing diarrhea, abdominal pain, and fever, and in some cases, organ failure and death. 

Other risk factors that can increase the risk of CDI include age over 65 years, hospitalization, nursing home residency, a weakened immune system, and/or a previous history of CDI. After recovering from CDI, individuals may get the infection again—often multiple times—a condition known as recurrent CDI. The risk of additional recurrences increases with each infection and treatment options for recurrent CDI are limited. The administration of fecal microbiota is thought to facilitate the restoration of the gut flora to prevent further episodes of CDI.

Vowst: Dosage and safety

The dosing regimen of Vowst is four capsules taken once a day, orally, for three consecutive days. Vowst contains live bacteria and is manufactured from human fecal matter that has been donated by qualified individuals. Although the donors and donated stool are tested for a panel of transmissible pathogens, Vowst may carry a risk of transmitting infectious agents. 

It is also possible for Vowst to contain food allergens; the potential for Vowst to cause adverse reactions due to food allergens is unknown.

The safety of Vowst was evaluated in a randomized, double-blind, placebo-controlled, clinical study and an open-label clinical study conducted in the US and Canada. The participants had recurrent CDI, were 48 to 96 hours postantibacterial treatment and their symptoms were controlled. 

Across both studies, 346 individuals 18 years of age and older with recurrent CDI received all scheduled doses of Vowst. In an analysis among 90 Vowst recipients, when compared to 92 placebo recipients, the most commonly reported side effects by Vowst recipients, which occurred at a greater frequency than reported by placebo recipients, were abdominal bloating, fatigue, constipation, chills, and diarrhea. 

The effectiveness of Vowst was evaluated in the randomized, placebo-controlled clinical study in which 89 participants received Vowst and 93 participants received a placebo. Through eight weeks after treatment, CDI recurrence in Vowst-treated participants was lower compared to placebo-treated participants (12.4 percent compared to 39.8 percent). 

- This press release was originally published on the U.S. Food and Drug Administration website