Role of oatp4c1 in renal handling of remdesivir and its nucleoside analog gs-441524: The first approved drug for patients with covid-19

– Purpose. Remdesivir and its active metabolite are predominantly eliminated via renal route; however, information regarding renal uptake transporters is limited. In the present study, the interaction of remdesivir and its nucleoside analog GS-441524 with OATP4C1 was evaluated to provide the detailed information about its renal handling. Methods. We used HK-2 cells, a proximal tubular cell line derived from normal kidney, to confirm the transport of remdesivir and GS-441524. To assess the involvement of OATP4C1 in handling remdesivir and GS-441524, the uptake study of remdesivir and GS-441524 was performed by using OATP4C1-overexpressing Madin-Darby canine kidney II (MDCKII) cells. Moreover, we also evaluated the IC₅₀ and K_i value of remdesivir. Results. The time-dependent remdesivir uptake in HK-2 cells was observed. The results of inhibition study using OATs and OCT2 inhibitors and OATP4C1 knockdown suggested the involvement of renal drug transporter OATP4C1. Remdesivir was taken up by OATP4C1/MDCKII cells. OATP4C1-mediated uptake of remdesivir increased linearly up to 10 min and reached a steady state at 30 min. Remdesivir inhibited OATP4C1-mediated transport in a concentration-dependent manner with the IC₅₀ and apparent K_i values of 42 ± 7.8 μM and 37 ± 6.9 μM, respectively. Conclusions. We have provided novel information about renal handling of remdesivir. Furthermore, we evaluated the potential drug interaction via OATP4C1 by calculating the K_i value of remdesivir. OATP4C1 may play a pivotal role in remdesivir therapy for COVID-19, particularly in patients with kidney injury.