TY - JOUR T1 - Pharmacokinetics, Metabolism, and Excretion of Anacetrapib, a Novel Inhibitor of the Cholesteryl Ester Transfer Protein, in Rats and Rhesus Monkeys JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 459 LP - 473 DO - 10.1124/dmd.109.028696 VL - 38 IS - 3 AU - Eugene Y. Tan AU - Georgy Hartmann AU - Qing Chen AU - Antonio Pereira AU - Scott Bradley AU - George Doss AU - Andy Shiqiang Zhang AU - Jonathan Z. Ho AU - Matthew P. Braun AU - Dennis C. Dean AU - Wei Tang AU - Sanjeev Kumar Y1 - 2010/03/01 UR - http://dmd.aspetjournals.org/content/38/3/459.abstract N2 - The pharmacokinetics and metabolism of anacetrapib (MK-0859), a novel cholesteryl ester transfer protein inhibitor, were examined in rats and rhesus monkeys. Anacetrapib exhibited a low clearance in both species and a moderate oral bioavailability of ∼38% in rats and ∼13% in monkeys. The area under the plasma concentration-time curve in both species increased in a less than dose-proportional manner over an oral dose range of 1 to 500 mg/kg. After oral administration of [14C]anacetrapib at 10 mg/kg, ∼80 and 90% of the radioactive dose was recovered over 48 h postdose from rats and monkeys, respectively. The majority of the administered radioactive dose was excreted unchanged in feces in both species. Biliary excretion of radioactivity accounted for ∼15% and urinary excretion for less than 2% of the dose. Thirteen metabolites, resulting from oxidative and secondary glucuronic acid conjugation, were identified in rat and monkey bile. The main metabolic pathways consisted of O-demethylation (M1) and hydroxylation on the biphenyl moiety (M2) and hydroxylation on the isopropyl side chain (M3); these hydroxylations were followed by O-glucuronidation of these metabolites. A glutathione adduct (M9), an olefin metabolite (M10), and a propionic acid metabolite (M11) also were identified. In addition to parent anacetrapib, M1, M2, and M3 metabolites were detected in rat but not in monkey plasma. Overall, it appears that anacetrapib exhibits a low-to-moderate degree of absorption after oral dosing and majority of the absorbed dose is eliminated via oxidation to a series of hydroxylated metabolites that undergo conjugation with glucuronic acid before excretion into bile. Copyright © 2010 by The American Society for Pharmacology and Experimental Therapeutics ER -