rifampin and famitinib

Famitinib is an oral, small-molecule, multi-targeted tyrosine kinase inhibitor under clinical investigation for the treatment of solid tumors. As famitinib is metabolized mainly by cytochrome P450 3A4 (CYP3A4), the study was conducted to investigate the effect of potent CYP3A4 inducer rifampin on the pharmacokinetics of famitinb.. This single-center, single-arm and fixed-sequence drug-drug interaction study enrolled 21healthy Chinese male subjects. Subjects received a single oral dose of famitinib 25 mg on days 1 and 16 and repeated administration of oral rifampin 600 mg once daily on days 10-23. Blood samples were collected and plasma concentrations of famitinib were measured by validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetic parameters were calculated using noncompartmental analysis and safety was assessed.. In the presence of rifampin, the famitinib geometric mean maximum plasma concentration (C. Co-administration of rifampin considerably reduces plasma concentration of famitinb due to CYP3A4 induction. Concomitant administration of famitinib and strong CYP3A4 inducers should be avoided, whereas when simultaneous use with inducers of CYP3A4, dose adjustment of famitinb is recommended.. NCT04494659 (July 31, 2020).

Topics: Chromatography, Liquid; Cytochrome P-450 CYP3A; Cytochrome P-450 CYP3A Inducers; Drug Interactions; Healthy Volunteers; Humans; Indoles; Male; Pyrroles; Rifampin; Tandem Mass Spectrometry