Baloxavir marboxil

Baloxavir marboxil is an antiviral drug used to treat influenza. More specifically, it is a first-in-class cap-dependent endonuclease inhibitor that works to block influenza virus proliferation. It is a prodrug of baloxavir with an improved absorption profile than its active metabolite due to the addition of a phenolic hydroxyl group to its structure. Baloxavir marboxil was first globally approved in Japan in February 2018, followed by the US approval in October, 2018. It was also approved by the European Commission on January 7, 2021.

Baloxavir marboxil is an influenza virus polymerase acidic (PA) endonuclease inhibitor indicated for the treatment of acute uncomplicated influenza in patients who have been symptomatic for no more than 48 hours and who are otherwise healthy adults and pediatric patients five years of age and older, or patients 12 years of age and older who are at high risk of developing influenza-related complications.

The drug is also indicated for post-exposure prophylaxis of influenza in patients five years of age and older following contact with an individual who has influenza. In Europe, it is approved for use in patients aged one year and above for these indications.

Baloxavir marboxil is associated with a risk for loss of efficacy due to changes in influenza virus such as changes in virus subtypes, emergence of virus resistance, and changes in viral virulence; therefore, the drug should be used after considering available information on drug susceptibility patterns for circulating influenza virus strains.