TY - JOUR T1 - A study of the effect of cyclosporine on fevipiprant pharmacokinetics and its absolute bioavailability using an intravenous microdose approach JF - Drug Metabolism and Disposition JO - Drug Metab Dispos DO - 10.1124/dmd.120.090852 SP - dmd.120.090852 AU - Markus Weiss AU - Ken-ichi Umehara AU - Veit Erpenbeck AU - Meredith Cain AU - Janardhana Vemula AU - Walid Elbast AU - Markus Zollinger Y1 - 2020/01/01 UR - http://dmd.aspetjournals.org/content/early/2020/07/30/dmd.120.090852.abstract N2 - This drug-drug interaction (DDI) study determined the effect of cyclosporine, an inhibitor of OATP1B3 and P-gp, on the pharmacokinetics (PK) of fevipiprant, an oral, highly selective, competitive antagonist of the prostaglandin D2 receptor 2 and a substrate of the two transporters. The concomitant administration of an intravenous (IV) microdose of stable isotope-labeled fevipiprant provided the absolute bioavailability of fevipiprant, as well as mechanistic insights in its PK and sensitivity to drug interactions. Liquid chromatography-mass spectrometry/mass spectrometry was used to measure plasma and urine concentrations. Geometric mean ratios (90% CI) for oral fevipiprant with or without cyclosporine were: for Cmax, 3.02 (2.38, 3.82); for AUClast, 2.50 (2.17, 2.88); and for AUCinf, 2.35 (1.99, 2.77). The geometric mean ratios (90% CI) for fevipiprant IV microdose with or without cyclosporine were: for Cmax, 1.04 (0.86, 1.25); for AUClast, 2.04 (1.83, 2.28) and for AUCinf, 1.95 (1.76, 2.16). The absolute bioavailability for fevipiprant was approximately 0.3-0.4 in the absence and 0.5 in the presence of cyclosporine. The IV microdose allowed differentiation between systemic and pre-systemic effects of cyclosporine on fevipiprant, demonstrating a small (approximately 1.2-fold) pre-systemic effect of cyclosporine and a larger (approximately 2-fold) effect on systemic elimination of fevipiprant. Uptake by OATP1B3 appears to be the rate-limiting step in the hepatic elimination of fevipiprant while P-gp does not have a relevant effect on oral absorption.SIGNIFICANCE STATEMENT The drug interaction investigated here with cyclosporine, an inhibitor of several drug transporters, provides a refined quantitative understanding of the role of active transport processes in liver and intestine for the absorption and elimination of fevipiprant, as well as the basis to assess the need for dose adjustment in the presence of transporter inhibitors. The applied IV microdose approach presents a strategy to maximize learnings from a trial, limit the number and duration of clinical trials, and enhance mechanistic DDI understanding. ER -