A little more than a year after rejoining Biogen Idec ($BIIB) as head of early-stage research, Michael Gilman is a free agent. Gilman left his position as executive vice president of research at Biogen back in 2005 to set up Stromedix, a biotech working on a new fibrosis treatment in-licensed from Biogen. And in early 2012 Biogen came back to buy the company for $75 million upfront and up to $487.5 million in milestones. Gilman, well known on Twitter, used the social media venue to announce his departure. For now, he tells the Boston Business Journal, he'll be taking the summer off as he contemplates his next step in the journey. Given his close ties to some happy investors and long track record in drug research, he's likely to come across more than a few opportunities. Story