With its once-yearly implanted-pump exenatide in phase III FREEDOM trials for type 2 diabetes, Intarcia Therapeutics Inc. became the highest-valued privately held biotech in the history of the industry by way of a $200 million financing that includes $57 million from the Foresite Capital Fund II, a growth equity stash designed to back firms “when we know things are working,” said managing director Christine Aylward.