Favipiravir (T-705) is a broad-spectrum antiviral agent that selectively and potently inhibits the RNA-dependent RNA polymerase (RdRp) of RNA viruses. It was discovered through screening chemical libraries for anti-influenza activity by Toyama Chemical Co., Ltd. Favipiravir undergoes intracellular phosphoribosylation to form its active form, favipiravir-RTP, which inhibits RdRp. This mechanism of action underpins the broad spectrum of antiviral activities of favipiravir, making it effective against a wide range of influenza viruses, including those resistant to existing antiviral drugs, as well as other RNA viruses such as arenaviruses, bunyaviruses, and filoviruses. Favipiravir has shown promising therapeutic effects in animal models of influenza and other RNA病毒感染，并且在临床研究中显示出良好的耐受性。由于其独特的抗病毒特性，Favipiravir被视为治疗RNA病毒感染的有希望的药物。Favipiravir (T-705) is a broad-spectrum antiviral agent that selectively and potently inhibits the RNA-dependent RNA polymerase (RdRp) of RNA viruses. It was discovered through screening chemical libraries for anti-influenza activity by Toyama Chemical Co., Ltd. Favipiravir undergoes intracellular phosphoribosylation to form its active form, favipiravir-RTP, which inhibits RdRp. This mechanism of action underpins the broad spectrum of antiviral activities of favipiravir, making it effective against a wide range of influenza viruses, including those resistant to existing antiviral drugs, as well as other RNA viruses such as arenaviruses, bunyaviruses, and filoviruses. Favipiravir has shown promising therapeutic effects in animal models of influenza and other RNA病毒感染，并且在临床研究中显示出良好的耐受性。由于其独特的抗病毒特性，Favipiravir被视为治疗RNA病毒感染的有希望的药物。