Estimation of changes in serum creatinine and creatinine clearance caused by renal transporter inhibition in healthy subjects

Creatinine is excreted into urine by glomerular filtration and renal tubular secretion through drug transporters such as organic anion transporter 2 (OAT2), organic cation transporter 2 (OCT2), OCT3, multidrug and toxin extrusion protein 1 (MATE1), and MATE2-K. We aimed to investigate whether our method for estimating percentage changes in serum creatinine concentration (SCr) and creatinine clearance (CLcre) from the baseline is applicable for studying renal transporter inhibitors. We tested 14 compounds (cimetidine, cobicistat, dolutegravir, dronedarone, DX-619, famotidine, INCB039110, nizatidine, ondansetron, pyrimethamine, rabeprazole, ranolazine, trimethoprim, and vandetanib), which were reported to cause reversible changes in SCr and/or CLcre in healthy subjects excluding elderly. Percentage changes were estimated from the relative contributions of the forementioned transporters to CLcre and competitive inhibition by these compounds at their maximum plasma unbound concentrations. For 7 and 9 out of these compounds, changes in SCr and/or CLcre were estimated within 2- and 3-fold of observed values, respectively. Less than 10% changes in SCr and/or CLcre caused by cobicistat, dolutegravir, and rabeprazole were reproduced as such by our method. These findings suggest that our method can be used to estimate changes in SCr and CLcre caused by competitive inhibitions of renal drug transporters. [Display omitted]