Inarigivir soproxil (SB9200) is an agonist of innate immunity and shows potent antiviral activity against resistant HCV variants, with EC50s of 2.2 and 1.0 μM for HCV 1a/1b in cells of genotype 1 HCV replicon systems. Inarigivir soproxil, an orally bioavailable proagent of SB 9000, has broad-spectrum antiviral activity against RNA viruses including HCV, norovirus, respiratory syncytial virus and influenza and HBV[1][2].