The Thousand Oaks drug giant Amgen Inc. has acquired a privately-held biopharmaceutical company based in Mountain View, Calif. Avidia develops a new type of human therapeutic called Avimer(TM) proteins. Its lead product candidate, in phase one clinic trials, is an inhibitor for the treatment of inflammation and autoimmune diseases. Amgen will pay $290 million in cash, net of existing cash balances and Amgen’s existing 4 percent equity stake in Avidia and up to $90 million upon the achievement of certain milestones. Boards from both companies have approved the deal.