Dissecting the Contribution of OATP1B1 to Hepatic Uptake of Statins Using the OATP1B1 Selective Inhibitor Estropipate

Abstract

Identification of a selective inhibitor of organic anion transporting polypeptide (OATP) 1B1 is critical in order to determine the contribution of OATP1B1-mediated uptake of investigational drugs into human hepatocytes for successful in vitro-to-in vivo extrapolation (IVIVE) of hepatic uptake and drug–drug interaction (DDI). The following study examined the inhibitory effects of estropipate (EPP) on major sinusoidal drug uptake transporters and explored its utility regarding IVIVE of statin hepatic disposition. EPP and its free-base form (i.e., estrone sulfate) showed a potent and high degree of selectivity in inhibiting the OATP1B1-mediated transport of rosuvastatin with an IC50 value averaging 0.05 ± 0.01 and 0.12 ± 0.07 μM for human and cynomolgus monkey OATP1B1 (hOATP1B1 and cOATP1B1), respectively, whereas weak inhibition was observed for human and monkey OATP1B3, OATP2B1, sodium-taurocholate cotransporting polypeptide (NTCP), organic anion transporter 2, and organic cation transporter 1 with IC50 values ranging from 8.6 to 64.0 μM. EPP, together with rifamycin SV, was subsequently used to determine the fractions of hepatic uptake clearance (f T) of statins, including rosuvastatin, pitavastatin, and dehydropravastatin, which are reported to be mediated by OATP1B1, OATP1B3, OATP2B1, and NTCP. Finally, the magnitudes of in vivo inhibition of rosuvastatin clearance caused by EPP and rifampin in cynomolgus monkeys were predicted by using individual transporter IC50 and f T (AUC fold change 1.28 vs 1.21, 2.71 vs 1.75, and 3.35 vs 2.83, respectively). These results suggest that EPP is an appropriate OATP1B1-selective inhibitor to establish the relative contribution of OATP1B1 to hepatic uptake in vitro and to discern the role of OATP1B1 in hepatic disposition in vivo.

Absence of OATP1B (Organic Anion–Transporting Polypeptide) Induction by Rifampin in Cynomolgus Monkeys: Determination Using the Endogenous OATP1B Marker Coproporphyrin and Tissue Gene Expression

“…Tandem Mass Spectrometry. The plasma concentrations of RIF, CPI, and CPIII were measured in plasma samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays described previously with slight modifications (Kandoussi et al, 2018, Zhang et al, 2019. A lower limit of quantification (LLOQ) of 0.078 nM was achieved for both CPI and CPIII using optimized sample extraction and LC-MS/MS conditions.…”

Static Model–Based Assessment of OATP1B1-Mediated Drug Interactions with Preincubation-Dependent Inhibitors Based on Inactivation and Recovery Kinetics

“…5 using pharmacokinetic parameters summarized in Supplemental Table 3 (Table 1). Contribution ratio (f value) of OATP1B1-mediated uptake to overall uptake of the three OATP1B1 substrates in human hepatocytes was estimated as the average of previously reported values (Kunze et al, 2014;Izumi et al, 2018;Zhang et al, 2019) (Table 1). The R 0 values of CsA without consideration of the preincubation effect were first calculated by eq.…”

Physiologically Based Pharmacokinetic Modeling of Rosuvastatin to Predict Transporter-Mediated Drug-Drug Interactions

“…5 Modeled rosuvastatin DDIs. Schematic illustration of the rosuvastatin transporters and metabolic enzymes inhibited by rifampicin, gemfibrozil, gemfibrozil glucuronide and probenecid, with the in vitro inhibition constants applied for DDI modeling [1,44,45,51,[66][67][68][69][70]. Numbers in parentheses refer to the in vitro literature references.…”

“…OATP1B1 was implemented as a substitute for the combined rosuvastatin transport by OATP1B1/1B3, to avoid identifiability problems fitting both transport rate constants and as OATP1B1 was reported to be more relevant for rosuvastatin liver uptake with a contribution of 77-88% [11,12]. In addition, very similar inhibition constants of rifampicin for these two members of the OATP family were published most recently (OATP1B1 Ki = 0.63 µM and OATP1B3 Ki = 0.69 µM [44], OATP1B1 Ki = 0.29 µM and OATP1B3 Ki = 0.50 µM [45]), that could not be utilized to differentiate the impact of these two OATP family members. In addition to the implemented active processes, the model calculates passive glomerular filtration and enterohepatic circulation of the rosuvastatin that is effluxed into the bile.…”