Boston biotech Alexion Pharmaceuticals Inc.’s fight to keep a hold on its flagship drug Soliris encountered a new challenge Friday, causing a stock drop that shaved more than $2 billion off the company’s market cap.
Alexion (Nasdaq: ALXN)'s finances rely heavily on its rare disease drug Soliris, which is used to treat the blood disorder paroxysmal nocturnal hemoglobinuria (PNH) and two autoimmune diseases. Paroxysmal nocturnal hemoglobinuria is estimated to affect between one and five people…
