Influenza A(H1N1)pdm09 virus exhibiting reduced susceptibility to baloxavir due to a PA E23K substitution detected from a child without baloxavir treatment

Antiviral Res. 2020 Aug:180:104828. doi: 10.1016/j.antiviral.2020.104828. Epub 2020 Jun 20.

Abstract

Human-to-human transmission of PA I38 mutant influenza A(H3N2) viruses with reduced baloxavir susceptibility has been reported in Japan. In December 2019, we detected a PA E23K mutant A(H1N1)pdm09 virus from a child without baloxavir treatment. The PA E23K mutant virus exhibited reduced baloxavir susceptibility but remained susceptible to neuraminidase inhibitors. Epidemiological data suggest possible transmission of this PA E23K mutant virus among humans, although its growth capability relative to that of the wild-type virus was reduced. Therefore, baloxavir susceptibility monitoring of influenza viruses is essential.

Keywords: Baloxavir; Cap-dependent endonuclease inhibitor; Influenza; Resistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Animals
  • Antiviral Agents / pharmacology*
  • Child
  • Dibenzothiepins / pharmacology*
  • Dogs
  • Drug Resistance, Viral / genetics*
  • Humans
  • Influenza A Virus, H1N1 Subtype / drug effects*
  • Influenza A Virus, H1N1 Subtype / genetics*
  • Influenza, Human / transmission
  • Influenza, Human / virology
  • Japan
  • Madin Darby Canine Kidney Cells
  • Morpholines / pharmacology*
  • Pyridones / pharmacology*
  • Triazines / pharmacology*
  • Viral Proteins / genetics*

Substances

  • Antiviral Agents
  • Dibenzothiepins
  • Morpholines
  • Pyridones
  • Triazines
  • Viral Proteins
  • baloxavir