Vertex Pharmaceuticals' nearly $10 billion buy of Crinetics Pharmaceuticals makes strategic sense, Evercore analysts say in a research note, even if the timing and size of the deal is a bit surprising. The deal shows Vertex continuing to diversify, adding a fifth therapeutic area to its portfolio with a new foothold in endocrinology, the analysts say. "If these assets ultimately generate anything close to Vertex's proposed $5B+ peak sales, then this is an easy win," they write. "Having said that, we don't believe that the deal needs to hit $5B+ in peak sales to be a success." Vertex shares are roughly flat in premarket trading Tuesday, while Crinetics shares double. (connor.hart@wsj.com)