Rhythm Boosts Series A Round to $40M, Adds Third Rock Ventures to List of Backers

Xconomy Boston — 

There’s new scientific and financial power behind the Boston biotech startup Rhythm Pharmaceuticals. Third Rock Ventures has joined as the company’s latest investor to help close its $40 million Series A funding round, and Third Rock partner Lou Tartaglia has joined the startup as a director and its chief scientist.

Rhythm, a developer of peptide (protein fragment) treatments for metabolic disorders, revealed back in March that it had closed $21 million of the first-round financing. Its original investors were MPM Capital and New Enterprise Associates. With Third Rock’s Tartaglia joining the executive team at Rhythm, the Boston venture firm is following its model of having its partners serve in senior roles at its portfolio companies in the early days of the startups. Tartaglia has previously served as an interim chief scientist for two of Third Rock’s other portfolio companies, Cambridge, MA-based biotech startups Agios Pharmaceuticals and Zafgen.

Unlike other biotech startups, Rhythm isn’t going to require several years of laboratory research before it discovers its first drugs. That’s because the firm has licensed its two lead drugs, RM-131, a peptide for treating gastrointestinal functional disorders, and RM-493, a peptide for treating obesity and diabetes, from the French biotech company Ipsen. (Ipsen, a global provider of peptide drugs, owns shares in Rhythm and has a seat on the startup’s board of directors). The company says that its first round of financing is intended to finance initial clinical studies of its lead molecules.

“Rhythm has broad and compelling data for both the [RM-131] and [RM-493] programs,” Third Rock’s Tartaglia said in a Rhythm press release. “I am very excited to join this team in building a great company in the metabolic field, and to help move these potential breakthrough products through pivotal clinical trials.”

Bart Henderson, Rhythm’s president and co-founder, wasn’t immediately available for comment on the financing deal at his office this morning.