Md. Anwer

Umifenovir is one of the most often prescribed antiviral medications for the prevention and treatment of COVID-19 and other viral infections. Herein, a UPLC-MS/MS method is developed through using ibrutinib as an internal standard (IS) for quantifying umifenovir in plasma samples. Both umifenovir and the IS were analytically separated on an Acquity BEH C18 column with a total run time of only 2.5 min. At a flow rate of 0.3 mLmin−1, acetonitrile:15 mM ammonium acetate (80:20) was employed as the mobile phase composition. Electrospray ionization in positive mode was used for ionization of the samples. Detection and quantification were performed in multiple reaction monitoring mode with parent-to-daughter ionization of 477.05 → 279.02 and 441.16 → 84.4 for umifenovir and the IS, respectively. The method was validated through following international guidelines for bioanalytical method validation, and all parameters were within the acceptable limits. Moreover, the eco-scale method using AGREE software was used for the evaluation of greenness, and results showed that the method is very environmentally friendly. The validated assay was successfully employed in the bioavailability assessment of a newly developed formulation of kneaded ternary umifenovir/β-cyclodextrin with 1% poloxamer 188 (KDB).