Quantitative Analysis of Favipiravir Spiked in Plasma Using by HPLC

As of 2020, the development of both pharmaceuticals and vaccines remains urgent to overcome the global coronavirus disease 2019 (COVID-19) pandemic. Favipiravir (brand name: Avigan^®), a promising drug candidate for COVID-19, is classified as an antiinfluenza drug, evaluated and developed for both novel and re-emerging influenza viruses. (1), (2) Favipiravir undergoes renal excretion, eliminated in the urine mainly as a hydroxide. Notably, the plasma levels of this drug are difficult to control owing to its once daily dosing regimen. (3) Consequently, the accurate monitoring of drug levels is crucial.