Vicadrostat, an aldosterone synthase inhibitor in development in combination with empagliflozin for chronic kidney disease, heart failure, and cardiovascular risk reduction, undergoes extensive hepatic glucuronidation primarily by UDP-glucuronosyltransferase (UGT)2B7 to form BI 689875, an ether glucuronide metabolite. Despite its hepatic formation, BI 689875 is predominantly excreted in urine, as determined in a human ADME study of vicadrostat. This study elucidated mechanisms underlying BI 689875 disposition in humans. BI 689875 was evaluated as a substrate of various drug transporters using transporter-expressing membrane vesicles and HEK293 cells. BI 689875 was identified as a substrate of MRP2, MRP3, MRP4, BCRP, OAT3, OATP1B1, and OATP1B3, but not of P-gp, OAT1, OAT2, OAT4, MATE1, or MATE2-K. The affinity of BI 689875 for MRP3 (Km = 39 μM) and OAT3 (Km = 46 μM) was substantially greater than that for other uptake/efflux transporters (not saturable up to 300 μM). In vitro-in vivo extrapolation using a proteomics-informed approach correcting for in vitro versus in vivo transporter expressions revealed that MRP3- and OAT3-mediated intrinsic clearance values for BI 689875 were substantially higher than those of other transporters. These findings suggest that basolateral efflux via MRP3 is the dominant hepatic elimination pathway for BI 689875, explaining its minimal fecal excretion observed in the human ADME study. They also indicate that OAT3-mediated uptake is the primary renal elimination route, with renal basolateral uptake substantially higher than hepatic uptake, consistent with the preferential urinary elimination of BI 689875. Transporter interplay between hepatic MRP3 and renal OAT3 determines the primary route of BI 689875 disposition. SIGNIFICANCE STATEMENT: BI 689875, a glucuronide metabolite, is formed in the liver but eliminated in urine. Through proteomics-informed in vitro-in vivo extrapolation, hepatic MRP3 and renal OAT3 were identified as key contributors to its predominant urinary elimination, highlighting interorgan transporter interplay.