Seres Therapeutics’ microbiome therapy flops against placebo as shares go into freefall

There’s been precious little good news for Seres Therapeutics of late, and the woe continues today as it records another trial failure.

Shares in the microbiome biotech fell more than 52% to $9.90 in early, premarket trading Thursday morning, from a prior close of $20.73. The fall was precipitated by data from a phase 2 trial which saw the company's ulcerative colitis (UC) candidate SER-287 flop against placebo in improving clinical remission rates, its primary endpoint.