Alexion stalks rare disease drug from Stealth with $30m opt-in dealAlexion has taken an option on a rare disease drug from Stealth Therapeutics in late-stage development, bolstering its Share XAlexion stalks rare disease drug from Stealth with $30m opt-in dealhttps://pharmaphorum.com/news/alexion-stalks-rare-disease-drug-from-stealth-with-30m-opt-in-deal/