Gene therapy player Dimension catches the biotech IPO wave, files $115M offering

Dimension Therapeutics is preparing to execute the next carefully planned step in its evolution, filing for a $115 million IPO close to 5 months after its crossover round landed. The filing came just days after the FDA accepted Cambridge, MA-based Dimension's IND for its lead gene therapy program, targeting a genetic fix for hemophilia B.

This filing has been brewing ever since the biotech finalized its $65 million raise in April, with New Leaf leading off with help from Jennison Associates, Partner Fund Management, RA Capital Management, Rock Springs Capital and Tourbillon Global Ventures. The original investors, Fidelity Biosciences and OrbiMed, also stepped back in on the round.

Dimension was founded by Fidelity, wooing former Merck Serono R&D chief Annalisa Jenkins to take the top job. Dimension was named a Fierce 15 company in 2014, alongside Voyager Therapeutics, another gene therapy developer which has put together its own crossover round. Dimension is the 8th Fierce 15 company from the class of 2014 to file an IPO, and at least two more appear to be positioning themselves for the leap in an unprecedented rush through an IPO window that has now been open for close to three years.

Despite some severe market turbulence, investors don't appear to have lost their appetite for risky biotech startups, yet. The IPOs keep coming, even as a few of the newly public companies like Celladon ($CLDN), Regado ($RGDO) and others have foundered badly, offering cautionary tales about the high wire most biotechs are balanced on.

Dimension's lead program for DTX101 uses an AAV vector to deliver Factor IX into hemophilia patients. It's one of several biotechs to focus their first gene therapy programs on hemophilia, which a number of experts believe makes a logical focus for the new wave of upstarts now working in the field.

Gene therapy has been booming over the past two years as developers like bluebird bio ($BLUE) have powered their way back in after the first generation of work was shelved following the emergence of lethal side effects. Biogen ($BIIB) focused its new gene therapy group on hemophilia, alongside Spark Therapeutics ($ONCE), RegenX--which outlicensed original tech to Dimension--and others. But for now there's more promise than performance, as new data start to reveal whether a single-dose fix can work safely.

Dimension still had a little more than $80 million in the bank at the end of June, after raising $89 million from investors and gathering $27 million from its partnership with Bayer.

- here's the S-1

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

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