FDA Approves Xofluza, a First-In-Class Flu Drug to Treat Symptoms It’s been almost 20 years since a new influenza (flu) treatment was approved, and last year’s flu season was one of the deadliest in decades. In response, the U.S. Food and Drug Administration (FDA) has approved Xofluza (baloxavir marboxil) for acute uncomplicated influenza in patients