Japan's Dainippon Sumitomo Pharma has expanded its alliance with upstart Edison Pharmaceuticals, committing $50 million to jointly develop treatments for orphan diseases with nearly $4 billion more tied to down-the-road milestones. The deal, which builds off of a March 2013 tie-up between the two, tasks Dainippon with funding the early development of 10 jointly discovered drugs, with Edison in line for as much as $4.3 billion in sum if each therapy wins approval in North America and Japan. More