Fecal Transplant Pill Fails Trial

Seres Therapeutics’s microbiome-targeting therapy for recurrent Clostridium difficile infection fails a Phase 2 clinical trial.

Jef Akst
Jef Akst

Jef Akst is managing editor of The Scientist, where she started as an intern in 2009 after receiving a master’s degree from Indiana University in April 2009 studying the mating behavior of seahorses.

View full profile.

Learn about our editorial policies.

WIKIMEDIA, CDC, HOLDEMANEarlier this year, Seres Therapeutics published promising data from an early-stage trial for its SER-109, a pill containing bacterial spores isolated from stool samples for patients with recurring Clostridium difficile infections (CDIs). The therapy seemed to be effective. But results announced last week (July 29) from a Phase 2 trial of 89 people with recurrent CDI were less positive: researchers found no significant difference between the treatment and control groups.                        

“The results were surprising, especially since the [Phase] 1b data was eye-popping,” Roger Pomerantz, the company’s CEO and president, told The Atlantic. “We’re now trying to dissect why there was a difference in the two trials.”

While the results may be a setback for SER-109, microbiome-based drugs still look promising, Diane Hoffman, director of the Law and Health Care Program at the University of...

Another company, Minnesota-based Rebiotix, is also developing a drug for antibiotic-resistant CDI. Whereas Seres researchers select specific bacterial species they put in the company’s treatment, Rebiotix’s drug, which completed enrollment in a Phase 2B trial last November, uses a suspension of all bacteria found in a donor stool sample. 

Interested in reading more?

The Scientist ARCHIVES

Become a Member of

Receive full access to more than 35 years of archives, as well as TS Digest, digital editions of The Scientist, feature stories, and much more!
Already a member?