UPDATED: Sanofi-backed MyoKardia nabs a $46M round for cardio pipeline construction

Sanofi ($SNY) partner MyoKardia is getting a fresh injection of capital, garnering $46 million in its Series B as the South San Francisco-based biotech plots the next stage of its clinical journey developing new drugs for genetically defined groups of heart patients.

Sanofi, which grabbed a $10 million piece of equity when it signed up to partner with MyoKardia last fall, came back for more in this round. Casdin Capital, Cormorant Asset Management, Perceptive Life Sciences, an affiliate of Cowen Group, and BridgeBio also jumped in. But Third Rock, which launched the company, was not mentioned in the release. An undisclosed public investment firm was involved, which will only fan speculation that the biotech just lined up a crossover round as it prepares a leap into the bustling IPO arena.

CEO Tassos Gianakakos steered clear of the IPO question, telling FierceBiotech that the new round gives the company plenty of flexibility.

"We're in a good spot," he adds. The money in this round will fund a runway "well into 2017" as MyoKardia continues to build on a staff that has risen to 52 just two-and-a-half years after launch. MyoKardia also just moved into a new facility in South San Francisco to accommodate the swelling staff, and the company is on track to nail down proof-of-mechanism for its lead therapy designed to treat an orphan heart indication.

"There's nobody doing what we're doing," says Gianakakos. "There are not a lot of companies focused on new disease biology. We're building a foundation here for the long run, with a long-term view in really getting closer to cures."

Last fall Sanofi paid $45 million up front and promised up to $200 million in added incentives to partner with MyoKardia, attracted by a research strategy targeting personalized small-molecule treatments that can address protein mutations in the sarcomere--part of the heart muscle--for small "buckets" of patients. The company is developing new drugs for hypertrophic and dilated cardiomyopathies.

Its lead drug, MYK-461, is now in Phase I for hypertrophic cardiomyopathies, looking to prevent overcontraction in genetically screened patients and reverse disease progression. By focusing on genetic subsets, MyoKardia has been pursuing a rare disease approach to a major market, flanking a field that's been dominated by a small group of giant players which can afford the huge studies needed to approve new heart drugs.

Third Rock provided a $38 million A round in 2012 to get the company off the launch pad. If MyoKardia does go the IPO route, it will join a pack of Third Rock biotechs moving into Nasdaq--a group that recently added Blueprint Medicines and will likely soon include Voyager Therapeutics and Jounce.

MyoKardia CEO Tassos Gianakakos

In many ways, the biotech is a classic Third Rock play. Partner Charles Homcy helped gather together a group of leading scientists in the field, including James Spudich at Stanford, Jonathan and Christine Seidman at Harvard and Leslie Leinwand at the University of Colorado at Boulder, to provide the scientific foundation. Then he stepped aside to let biotech vet Gianakakos take the helm.

"The enthusiasm from the investment community is a reflection of the hard work and dedication of our scientists and employees, founders and collaborators all sharing MyoKardia's vision to transform the lives of patients suffering from these devastating diseases," said Gianakakos in a statement. "The investment of resources and expertise by our new shareholders helps MyoKardia continue to strengthen its scientific leadership position and advance our therapeutic programs as quickly and responsibly as possible."

- here's the release

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