Kevin Sharer, former chief executive at Amgen Inc., has joined venture capital firm Foundation Medical Partners as a partner, the private investment company said Tuesday. Sharer stepped down as chief executive of the Thousand Oaks biopharmaceutical firm in May, a position he held since 2000. He also stepped down as board chairman in December, severing his ties to the company he had been with for more than 20 years. He was replaced in both positions by Robert Bradway, who had been chief operating officer. Foundation Medical is a Rowayton, Conn. venture capital firm with interests in early-stage health care technology startups. The company was formed in 2001, and has previously invested in companies including Seattle medical device firm Northstar Neuroscience Inc., Pennsylvania cardiac monitoring device maker CardioNet Inc. and Ohio surgical device maker AtriCure Inc. “Kevin has had a long affiliation with Foundation and we are excited to bring him on board,” said Andrew Firlik, managing partner at the firm, in a statement. “He has already been adding his operational expertise and strategic guidance to our portfolio companies.” Sharer will be a member of the company’s health care investment team, tasked with assessing and managing investments used in remote health care and health care technology. During Sharer’s tenure at Amgen, the company was not known for its spinoffs, despite the formation of its own venture capital arm, Amgen Ventures. The investment division recently backed its first local spin-off, Atara Biotherapeutics, in a joint venture with Menlo Park venture capital firm Kleiner Perkins Caufield & Byers.