Simultaneous Quantification of Filgotinib and Its Active Metabolite in Human Plasma Using Liquid Chromatography-Tandem Mass Spectrometry: Validation and Clinical Application.

ABSTRACT: Filgotinib (FLG) is a Janus kinase 1 inhibitor and is metabolized to an active metabolite, GS-829845. There is no report on the method for simultaneous quantification of FLG and GS-829845 in clinical samples. We developed a liquid chromatography-tandem mass spectrometry method for simultaneous determination of FLG and GS-829845 in patient plasma. FLG and GS-829845 were extracted from an aliquot of 50 μL of human plasma by simple deproteinization using methanol. Chromatographic separation was performed using a Shim-pack Scepter C18-120 column with a combined mobile phase of water and methanol containing 0.1% formic acid and gradient elution at a flow rate of 0.2 mL/min. Detection was performed by positive electrospray ionization using a QTRAP 4500 mass spectrometer. The method was validated

SUBMITTER: Ito T 

PROVIDER: S-EPMC11837455 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature