A revised U.S. label for Glaxosmithkline plc's Nucala (mepolizumab) has expanded the first-in-class anti-IL-5 treatment's approval to hypereosinophilic syndrome (HES), a group of rare disorders associated with persistent eosinophilia. It's the new therapy approved for Americans with HES in nearly 14 years, according to the FDA. An EMA filing in HES is expected later this year.