Seres guts out a $134M IPO to fuel microbiome R&D

Cambridge, MA's Seres Therapeutics ($MCRB) pulled off an above-its-range IPO, grossing about $134 million to bankroll its work on drugs that change the weather in the gut to treat disease.

The company priced about 7.4 million shares at $18 each, beating its expected range of $15 to $17. Seres set aside another 1.1 million shares for its underwriters to cover overallotments, setting its maximum IPO value north of $150 million.

With the proceeds, Seres plans to push forward with SER-109, a Tylenol-sized capsule designed to treat recurrent Clostridium difficile infections by changing patients' bacterial makeup. Inside each person is an ecosystem of more than 100 trillion microorganisms, making up what scientists have termed the microbiome, and Seres has crafted a treatment made up of spores that can alter the state of that ecosystem to combat disease.

SER-109 secured the FDA's coveted breakthrough-therapy designation earlier this month, guaranteeing Seres access to top FDA officials as the drug moves forward and promising a truncated review process once the company submits its candidate. The pill is now in a Phase II study slated to wrap up in the middle of next year, and Seres plans to start Phase III development thereafter.

Behind its lead prospect, Seres is working a preclinical C. diff. treatment called SER-262 and a handful of early-stage candidates for inflammatory bowel diseases and bacterial infections.

Key to the biotech's work is its proprietary development engine, dubbed Ebiotics, through which the company compares the gut compositions of healthy people with those suffering from a targeted disease. Using proprietary algorithms, Seres then determines what in the former gut is missing from the latter, growing the spores needed to match the two and packaging them in a tablet.

Meanwhile, a steady stream of biotech IPOs has 2015 on pace to beat out last year's record haul. More than 30 drug developers have gone public in the first half, and the third-quarter queue is already filling up, with Australia's Benitec Biopharma filing to raise $70 million to support its work in gene therapies for hepatitis C while ADHD drug developer Neos Therapeutics is looking for $69 million and Patrick Soon-Shiong's Conkwest is angling for a $173 million IPO.

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Special Report: FierceBiotech's 2014 Fierce 15 - Seres Health

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