title: Lumiracoxib metabolism in male C57bl/6J mice: characterisation of novel in vivo metabolites.
abstract: 1. The pharmacokinetics and metabolism of lumiracoxib in male C57bl/6J mice were investigated following a single oral dose of 10 mg/kg. 2. Lumiracoxib achieved peak observed concentrations in the blood of 1.26 + 0.51 μg/mL 0.5 h (0.5-1.0) post-dose with an AUCinfof 3.48 + 1.09 μg h/mL. Concentrations of lumiracoxib then declined with a terminal half-life of 1.54 + 0.31 h. 3. Metabolic profiling showed only the presence of unchanged lumiracoxib in blood by 24 h, while urine, bile and faecal extracts contained, in addition to the unchanged parent drug, large amounts of hydroxylated and conjugated metabolites. 4. No evidence was obtained in the mouse for the production of the downstream products of glutathione conjugation such as mercapturates, suggesting that the metabolism of the drug via quinone-imine generating pathways is not a major route of biotransformation in this species. Acyl glucuronidation appeared absent or a very minor route. 5. While there was significant overlap with reported human metabolites, a number of unique mouse metabolites were detected, particularly taurine conjugates of lumiracoxib and its oxidative metabolites.
authors.affiliation: a Evotec UK Ltd , Milton Park, Abingdon , UK.
authors.forename: Anthony
authors.initials: A
authors.lastname: P Dickie
authors.affiliation: a Evotec UK Ltd , Milton Park, Abingdon , UK.
authors.forename: Claire E
authors.initials: CE
authors.lastname: Wilson
authors.affiliation: b Evotec International GmbH , In Vivo Pharmacology, Göttingen , Germany , and.
authors.forename: Kay
authors.initials: K
authors.lastname: Schreiter
authors.affiliation: b Evotec International GmbH , In Vivo Pharmacology, Göttingen , Germany , and.
authors.forename: Roland
authors.initials: R
authors.lastname: Wehr
authors.affiliation: c Imperial College London, Surgery and Cancer , London.
authors.forename: Ian
authors.initials: I
authors.lastname: D Wilson
authors.affiliation: a Evotec UK Ltd , Milton Park, Abingdon , UK.
authors.forename: Rob
authors.initials: R
authors.lastname: Riley
mesh_terms: D000818:Animals; D052246:Cyclooxygenase 2 Inhibitors / Q000378:metabolism*; D004008:Diclofenac / Q000031:analogs & derivatives* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D004008:Diclofenac; C473384:lumiracoxib
keywords: Glucuronide conjugation; quinone imine; reactive intermediate; taurine conjugation