Gene Therapy Upstart Dimension Nabs $65M From “Crossover” Backers

Xconomy Boston — 

The race is on to be the first to market with a gene therapy for hemophilia. And one of the entrants just got a big round of funding in what looks like a prelude to an initial public offering.

Cambridge, MA-based Dimension Therapeutics has raised a $65 million Series B round from a group of investors led by New Leaf Venture Partners and including several “crossover” backers—firms that support both public and private companies. Among Dimension’s new investors: RA Capital Management, Rock Springs Capital, Partner Fund Management, Jennison Associates, Tourbillon Global Ventures, and another unnamed “life sciences investor.” Existing backers Fidelity Biosciences—which started Dimension a few years ago via a deal with Washington, DC-based RegenxBio—also participated, as did OrbiMed Advisors.

Rounds like these typically signal a startup is, at minimum considering an IPO. Just last week, Voyager Therapeutics, another gene therapy startup, got $60 million in a round that had some crossover investors, and confirmed to Xconomy that those backers would “help support a future potential IPO.”

For Dimension, the round continues a quick ramp-up since its October 2013 launch. The startup closed out a $30 million Series A last June, adding New York’s OrbiMed to its investor base, and cut a partnership with Bayer potentially worth $252 million on the same day. Including the $20 million up front check it got from Bayer, the startup has raised over $100 million since its inception 18 months ago.

The company has also filled out its management team. It hired Merck Serono’s former research chief, Annalisa Jenkins, as its CEO in September (taking over for interim CEO and Fidelity executive partner Tom Beck), and later named former Cubist business development executive Mary Thistle as its chief business officer.

Annalisa Jenkins

Annalisa Jenkins

Dimension is one of the startups to emerge over the past few years amidst a renaissance for gene therapy, a field once stymied safety issues, but now hot again in part because of promising data and better delivery technologies.

The startup is tied to the work of University of Pennsylvania gene therapy specialist James Wilson. Wilson co-led the infamous clinical trial that led to the death of teenager Jesse Gelsinger in 1999, but went on to become a key figure in advancing what’s now the most commonly used gene therapy delivery tool, adeno-associated virus, or AAV.

Wilson’s AAV work led to RegenX, and Dimension was formed with a license to several of the startup’s vectors. (RegenX has given other startups, like Audentes Therapeutics, access to its vectors as well.) Dimension aims to use the technology to target rare metabolic disorders associated the liver—it hasn’t said which ones yet—and hemophilia A and B.

Dimension’s hemophilia B program is the furthest along so far; it’s expected to begin clinical testing in the second half of this year. That treatment is one of at least seven in development for hemophilia, a disorder that leaves patients without the cellular machinery needed to clot blood. For more on that race, which includes companies like Spark Therapeutics (NASDAQ: ONCE), BioMarin Pharmaceutical (NASDAQ: BMRN), Baxter International (NYSE: BAX), Biogen (NASDAQ: BIIB), UniQure (NASDAQ: QURE), Sangamo Biosciences (NASDAQ: SGMO), and gene therapy’s long history battling hemophilia, check out this story from March.

Dimension, meanwhile, aims to ask the FDA over the next 12 to 18 months for permission to begin clinical tests for other gene therapies for rare diseases. Dimension wants three such therapies to be ready for clinical testing next year.

“We are pleased with the substantial support from new and existing investors. The strong demand in our Series B affirms the rapid progress we have achieved to date and reflects continued broad interest in the promise of gene therapy to address compelling unmet needs in the treatment of rare diseases,” Jenkins said in a statement. “We are well-capitalized for the next stage of our development as we advance our lead programs into the clinic and continue to expand our R&D pipeline focused on rare diseases associated with the liver.”

New Leaf partner Mike Dybbs joined Dimension’s board as part of the financing.