UCB Pharma has entered an agreement to acquire Ra Pharmaceuticals in deal valued at $2.5 billion. The acquisition will add zilucoplan, a Phase III candidate to potentially compete with Alexion’s Soliris, a monoclonal antibody for the treatment of rare chronic blood disorders, paroxysmal nocturnal hemoglobinuria (PNH), and atypical hemolytic uremic syndrome. Soliris had sales of nearly $3.6 billion in 2018.   Ra’s zilucoplan is a once-daily, self-administered, subcutaneous C5 inhibitor in Phase I...