Glaxo, Atlas syndicate bankrolls Spero's drive into the clinic with $30M round

Spero CEO Ankit Mahadevia

Eight months after wrapping its first venture round with a $30 million bankroll, Cambridge, MA-based Spero Therapeutics has gone back to the well for $30 million more.

This new round brought all the original investors back to the table: Atlas Venture, SR One (the venture arm of GlaxoSmithKline), Merck Research Ventures, Lundbeckfond Ventures, The Kraft Group (a conglomerate run by Patriots owner Robert Kraft) and Partners Innovation Fund.

"We've grown faster than planned, in a good way," says Spero CEO Ankit Mahadevia. "It's a different company from the company that received a Series A."

Last spring the company was still relatively small, he adds. And since then the biotech has built its staff up to 20 and growing, added new platform tech and built an anti-infectives pipeline strategy that extends from treatments in the hospital to a community setting, with plans to begin clinical work soon.

Spero is among a group of biotechs that have been angling to take advantage of new incentives on both sides of the Atlantic to develop antibiotics that can counterpunch drug-resistant superbugs that threaten public health. And Mahadevia is tracking new legislative activity in the U.S. as well as Europe that might add some fresh bonuses for companies in the field. Among the big players in R&D, both Roche ($RHHBY) and Merck ($MRK) have been upping their involvement in the field. And Spero, a 2014 Fierce 15 company, partnered with Roche early on one program.  

Spero in-licensed new "potentiator" technology aimed at greatly expanding the reach of existing antibiotics, which is moving closer to human studies. The big idea here is that by scrambling the protective out membrane of gram negative bacteria--which prevents antibiotics from penetrating them--they will be able to use gram-positive antibiotics against them.

Now Mahadevia and his team have enough cash to pursue the work into late 2017, by which time he'll have the data in hand needed to move on to the next stage of development, with more time to assess potential collaborations with others.

Special Report: FierceBiotech's 2014 Fierce 15 - Spero Therapeutics

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