PT  - JOURNAL ARTICLE
AU  - Chun Yang
AU  - Dongmei Zhou
AU  - Zancong Shen
AU  - David M. Wilson
AU  - Matthew Renner
AU  - Jeffrey N. Miner
AU  - Jean-Luc Girardet
AU  - Caroline A. Lee
TI  - Characterization of Stereoselective Metabolism, Inhibitory Effect on Uric Acid Uptake Transporters, and Pharmacokinetics of Lesinurad Atropisomers
AID  - 10.1124/dmd.118.080549
DP  - 2019 Feb 01
TA  - Drug Metabolism and Disposition
PG  - 104--113
VI  - 47
IP  - 2
4099  - http://dmd.aspetjournals.org/content/47/2/104.short
4100  - http://dmd.aspetjournals.org/content/47/2/104.full
SO  - Drug Metab Dispos2019 Feb 01; 47
AB  - Lesinurad [Zurampic; 2-(5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-triazol-3-ylthio)], a selective inhibitor of uric acid reabsorption transporters approved for the treatment of gout, is a racemate of two atropisomers. The objective of this investigation was to evaluate the stereoselectivity of metabolism, the inhibitory potency on kidney uric acid reabsorption transporters (URAT1 and OAT4), and the clinical pharmacokinetics of the lesinurad atropisomers. Incubations with human liver microsomes (HLM), recombinant CYP2C9, and recombinant CYP3A4 were carried out to characterize the stereoselective formation of three metabolites: M3 (hydroxylation), M4 (a dihydrodiol metabolite), and M6 (S-dealkylation). The formation of M3 in HLM with atropisomer 1 was approximately twice as much as that with atropisomer 2, whereas formation of M4 with atropisomer 1 was 8- to 12-fold greater than that with atropisomer 2. There were no significant differences in the plasma protein binding among lesinurad and the atropisomers. Following oral administration of 400 mg lesinurad once daily for 14 days to healthy human volunteers, the systemic exposure (Cmax at steady state and area under the concentration-time curve from time zero to the time of dosing interval) of atropisomer 1 was approximately 30% lower than that of atropisomer 2, whereas renal clearance was similar. In vitro cell-based assays using HEK293 stable cells expressing URAT1 and OAT4 demonstrated that atropisomer 2 was approximately 4-fold more potent against URAT1 than atropisomer 1 and equally active against OAT4. In conclusion, lesinurad atropisomers showed stereoselectivity in clinical pharmacokinetics, metabolism, and inhibitory potency against URAT1.