Sage up-sizes its ambition on the eve of a much-watched IPO

Biotech luminary Sage Therapeutics is boosting the size of its planned IPO, upping its share offering and expected price range as investors look to its Wall Street debut as a bellwether for the industry.

In an amended SEC filing, Sage disclosed that it plans to boost its offering by 20% to offer 5 million shares at between $17 and $18 each, making for an $80 million midpoint, a 25% jump over its previous plans. The company has set aside another 570,000 shares to cover overallotments, setting its maximum deal value at $103.5 million.

The Cambridge, MA, drug developer plans to use $10 million of its proceeds to fund Phase I/II study of SAGE-547, a therapy for super-refractory status epilepticus (SE). Another $10 million will pay for preclinical work on SAGE-689, designed to treat adjunctive SE, with $7 million earmarked for SAGE-217, a pre-IND treatment designed to be a maintenance therapy for the disease, and the rest going toward general corporate costs. SE is a rare, life-threatening seizure condition with no approved treatments, according to the company.

Sage's up-sized offering comes at a trying time for biotechs on the public markets. Last month, antibody specialist Ambrx pulled the plug on an $86 million offering due to unfavorable market conditions, and Syndax Pharmaceuticals and GlobeImmune failed to pull off planned offerings that would have totaled nearly $400 million.

This week is expected to host another 6 debuts by life sciences companies, but of the successes so far--CareDx ($CDNA), Roka Bioscience ($ROKA) and iRadimed ($IRMD)--two had to take substantial discounts to execute their plans, and iRadimed's micro offering raised just $13 million.

That puts the spotlight on Sage, considered to be among the most promising biotechs left in the industry's IPO queue. If the Third Rock Ventures alum can come through on its debut, it could help bring about a warmer reception for the next line of hopefuls, which includes Otonomy, Immune Design and Zosana Pharma.

- read the amended filing