Receptos, a San Diego-based developer of G protein-coupled receptor therapeutics, has secured $50 million in new VC funding, according to a regulatory filing. The company’s lead drug candidate is aimed at treating patients with multiple sclerosis.

My understanding is that Polaris Venture Partners came in as the new lead, with Receptos so far having called down around $10 million of the tranched-out deal. The company previously raised more than $25 million from firms like ARCH Venture Partners, Flagship Ventures, Lilly Ventures and Venrock.

The company declined to comment on the financing.

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