Seres Therapeutics notches FDA win a decade in the making

Seres Therapeutics Inc., which has spent more than 10 years developing a drug that targets microbiomes, received its first approval by the U.S. Food and Drug Administration.

After 6 p.m., on Wednesday, almost 10 years after SER-109 was tested for the first time in humans, the FDA approved the drug. Seres' stock price fell slightly in the after-hours market. The market capitalization for the company is $814.4 millions.

Seres is marketing the drug as Vowst. Nestle Health Science, a long-time partner of Seres's, will cocommercialize the drug in the U.S. Seres also receives a $125m milestone payment as a result.

In a press release, CEO Eric Shaff stated that "Since Flagship Pioneering founded Seres over a decade back, Seres led the development and approval of microbiome therapies. Today's FDA approval for Vowst, the first microbiota based oral therapeutic to prevent recurrent C. diff infection, marks a huge milestone for both the patient community and Seres." "We are grateful to all the patients, caregivers and clinical investigators who have contributed to the development of Vowst.

Vowst began in the basement of a lab in Kendall Square. In 2012, there were only a few people on the team testing a theory which had just begun to gain traction with academic scientists. The theory was that by transplanting 'good bacteria' in sick patients, they could restore the balance between the complex microbial community living within their gastrointestinal tracts, and restore the health of the patients.

Seres started testing the drug on C. diff in 2013 The drug was a success from the start, bringing in $123 million of venture funding for Seres, a $133-million IPO, and a partnership between Nestle Health Science within two years after its first Phase 1-data readout.

Shaff, who was interviewed by the Business Journal in a recent company profile, said that it was a 'clear signal' that the company could have an effect on the disease. The notion that we continue to pursue is the fact that the gut microbiome's health has profound implications on human health.

The FDA's Wednesday decision seems to confirm that opinion. It was an emotional rollercoaster ride to reach this point. The mid-stage study interim results showed that SER109 was no more effective at preventing C. diff recurrence than a placebo. The company took several years to recover its footing and launch a Phase 3-trial with FDA feedback. They also had to win back investors' confidence.

Peter Marks said that the FDA Center for Biologics Evaluation and Research's Center for Biologics Evaluation and Research approved this product today. The FDA's Center for Biologics Evaluation and Research Director, Peter Marks, said in a statement that the availability of an oral fecal-microbiota product is a major step forward to improve patient care.

Seres also works on other microbiota-based drugs. The company is partnered with Memorial Sloan Kettering Cancer Center in order to develop treatments that will reduce the risk for infections among cancer patients, and improve the effectiveness of cancer drugs.

Seres has also developed programs for ulcerative colitis. However, these are on hold due to disappointing results. The company is analyzing its studies, as it did in 2016 and 2017 with SER109, to determine a course of action.