Two members of the board of biotechnology start-up Verastem Inc. have made large purchases of the Cambridge company’s common stock.
Lead director Henri A. Termeer, the retired chief executive of Genzyme Corp., bought 11,356 shares of Verastem at $9.35 apiece, documents filed with the Securities and Exchange Commission show.
A separate document said director John K. Clarke, cofounder of the venture capital firm Cardinal Partners, bought 25,000 shares of Verastem at $9.21 a share, lifting his holdings to 2,305,959 shares.
Verastem’s chairman, Christoph Westphal, who will be stepping down as chief executive July 1, is the company’s largest shareholder, owning 17.5 percent of its stock as of April 25 —
Westphal will be replaced as Verastem’s chief executive by Robert Forrester, who currently serves as the company’s president and chief operating officer.