Long Courtship Preceded GlaxoSmithKline’s Sirtris Acquisition

Xconomy Boston — 

GlaxoSmithKline’s purchase of Cambridge, MA-based Sirtris Pharmaceuticals—a deal completed today—was on the drawing boards long before it made headlines in late April, according to an interesting story by Boston Globe reporter Todd Wallack.

“We’re getting married to someone that we’ve been dating for a while,” Sirtris CEO Christoph Westphal told Wallack.

Sirtris, which went public just last year, is developing drug candidates that treat conditions such as diabetes and cancer by activating sirtuins, a class of proteins in the body that are involved in regulating metabolism and lifespan. GlaxoSmithKline, headquartered in London and Philadelphia, was attracted to the company because sirtuin research could help round out its pipeline of drugs for metabolic, neurological, immunological, and inflammation-related disorders.

Wallack’s article, which is based on SEC filings and interviews with Westphal, says that talks last August between the two companies about a possible GSK investment in Sirtris quickly evolved into merger discussions. In early April, GSK offered $18.50 to $19.50 per share for the company, Wallack reports, but Sirtris was able to talk the pharmaceutical giant up to $22.50 per share, or $720 million.

That will produce a nice windfall for Westphal himself (who stands to earn up to $25 million from the acquisition), for venture investors Polaris Venture Partners and Cardinal Partners, and for a lineup of prominent Bostonians that includes Red Sox owner John Henry, former Fidelity money manager Peter Lynch, Celtics manager Wyc Grousbeck, and former U.S. Congressman Joseph P. Kennedy II.

The acquisition agreement calls for Sirtris to remain an autonomous unit within GSK for three years, and GSK has offered Westphal a $2 million bonus incentive if he stays on for at least four years, according to Wallack.