Baloxavir marboxil: the new influenza drug on the market.

For the first time in nearly 20 years there is a new class of antiviral drug for influenza. The latest approved antiviral is baloxavir marboxil (trade name, Xofluza) which targets the endonuclease function of the viral PA polymerase subunit and prevents the transcription of viral mRNA. The most promising aspect of this new drug is its pharmacology which allows for effective treatment of influenza A or B virus infection with just a single dose. A clinical trial showed greater reductions in viral loads with baloxavir marboxil treatment compared with oseltamivir, although no difference in the time to alleviation of symptoms between these two drugs. With this new class of influenza drug comes exciting prospects for combination therapy with the neuraminidase inhibitors which may help to abate concerns about the development of resistance.