Seres Lays Off 30% of Staff, CSO Leaves After Pipeline Review

Xconomy Boston — 

Seres Therapeutics was one of the first microbiome companies to form, back in 2010. And the Flagship Pioneering company was the first to go public. But today, faced with the challenges of developing a fundamentally different kind of therapeutic—consortia of human microbes—the company said it is axing 30 percent of its staff (around 30 employees and contractors), and that David Cook, its chief scientific officer, will be replaced by Matthew Henn, who was head of discovery and microbiome R&D. The layoffs will be in research, manufacturing and administration, and Cook will act as a consultant.

In a prepared statement, Cambridge, MA-based Seres (NASDAQ: MCRB) said that after a pipeline review, it has decided to focus on SER-287, in Phase 2 testing for ulcerative colitis, and SER-401, being tested in combination with a cancer immunotherapy in a Phase 1 trial in melanoma patients. Seres will also continue working on a preclinical product, SER-301, for ulcerative colitis.

The Phase 3 study of lead Seres program, SER-109, for patients with Clostridium difficile infection, will also continue, but the company admitted that it was struggling to recruit patients who weren’t already being treated with fecal transplants. SER-109 failed a Phase 2 trial in 2016, but got the go-ahead from the FDA in 2017 to start a larger trial that the company hoped would generate the data needed for the approval of the first-ever microbiome drug.

The layoffs come less than a month after longtime Seres CEO Roger Pomerantz stepped away and became board chairman. He was replaced as CEO by chief operating and financial officer Eric Shaff.

Seres’s share price is down slightly today, to $5.86 apiece. Seres made its stock market debut at more than $50 apiece in 2015.