title: Voriconazole increases while itraconazole decreases plasma meloxicam concentrations.
abstract: This study investigated the effect of voriconazole, an inhibitor of cytochrome P450 2C9 (CYP2C9) and CYP3A4, and itraconazole, an inhibitor of CYP3A4, on the pharmacokinetics and pharmacodynamics of meloxicam. Twelve healthy volunteers in a crossover study ingested 15 mg of meloxicam without pretreatment (control), after voriconazole pretreatment, and after itraconazole pretreatment. The plasma concentrations of meloxicam, voriconazole, itraconazole, and thromboxane B(2) (TxB(2)) generation were monitored. Compared to the control phase, voriconazole increased the mean area under the plasma concentration-time curve from 0 to 72 h (AUC(0-72)) of meloxicam by 47% (P < 0.001) and prolonged its mean half-life (t(1/2)) by 51% (P < 0.01), without affecting its mean peak concentration (C(max)). In contrast, itraconazole decreased the mean AUC(0-72) and C(max) of meloxicam by 37% (P < 0.001) and by 64% (P < 0.001), respectively, and prolonged its t(1/2) and time to C(max). The plasma protein unbound fraction of meloxicam was unchanged by voriconazole and itraconazole. Lowered plasma meloxicam concentrations during the itraconazole phase were associated with decreased pharmacodymic effects of meloxicam, as observed by weaker inhibition of TxB(2) synthesis compared to the control and voriconazole phases. Voriconazole increases plasma concentrations of meloxicam, whereas itraconazole, unexpectedly, decreases plasma meloxicam concentrations, possibly by impairing its absorption.
authors.affiliation: Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland. vilhyn@utu.fi
authors.forename: V V
authors.initials: VV
authors.lastname: Hynninen
authors.forename: K T
authors.initials: KT
authors.lastname: Olkkola
authors.forename: L
authors.initials: L
authors.lastname: Bertilsson
authors.forename: K J
authors.initials: KJ
authors.lastname: Kurkinen
authors.forename: T
authors.initials: T
authors.lastname: Korhonen
authors.forename: P J
authors.initials: PJ
authors.lastname: Neuvonen
authors.forename: K
authors.initials: K
authors.lastname: Laine
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000097:blood*; D000935:Antifungal Agents / Q000494:pharmacology*; D001777:Blood Coagulation / Q000187:drug effects; D018592:Cross-Over Studies; D051545:Cyclooxygenase 1 / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004347:Drug Interactions; D005838:Genotype; D006207:Half-Life; D006801:Humans; D017964:Itraconazole / Q000494:pharmacology*; D008297:Male; D000077239:Meloxicam; D011485:Protein Binding; D011743:Pyrimidines / Q000494:pharmacology*; D013843:Thiazines / Q000097:blood*; D013844:Thiazoles / Q000097:blood*; D013929:Thromboxane B2 / Q000096:biosynthesis; D014230:Triazoles / Q000494:pharmacology*; D065819:Voriconazole; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000935:Antifungal Agents; D011743:Pyrimidines; D013843:Thiazines; D013844:Thiazoles; D014230:Triazoles; D017964:Itraconazole; D013929:Thromboxane B2; D003577:Cytochrome P-450 Enzyme System; D051545:Cyclooxygenase 1; D065819:Voriconazole; D000077239:Meloxicam