Medication Monitor

Generic Name (Trade Name—Company)
October 31, 2019

Baloxavir marboxil

FDA approves Xofluza for people at high risk of developing flu-related complications

On October 17, Genentech announced FDA approval of baloxavir marboxil for the treatment of acute, uncomplicated influenza in people ages 12 years and older who have been symptomatic for no more than 48 hours and are at high risk of developing flu-related complications. This first-in-class, one-dose oral medication has a novel proposed mechanism of action that inhibits polymerase acidic endonuclease, an enzyme essential for viral replication.

This expanded indication was approved on the basis of results from the Phase III CAPSTONE-2 study of a single dose of baloxavir marboxil 40 mg or 80 mg compared with oseltamivir 75 mg twice daily for 5 days or placebo in people aged 12 years of age or older who met CDC criteria for being at high risk of complications from the flu.

Baloxavir marboxil significantly reduced the time to improvement of flu symptoms compared with placebo, including in people infected with flu type B virus.

Adverse events, reported in at least 1% of adult and adolescent participants treated with baloxavir marboxil, included diarrhea, bronchitis, nausea, sinusitis, and headache.

Baloxavir marboxil is currently approved in several countries for treatment of flu types A and B. In October 2018, the medication was first approved for treatment of acute, uncomplicated flu in otherwise healthy people ages 12 years and older who have been symptomatic for no more than 48 hours, representing the first new antiviral to treat the flu in the United States in 20 years.