The pharmacokinetics of mavacoxib, a long-acting COX-2 inhibitor, in young adult laboratory dogs.

Autor: Cox SR; Veterinary Medicine Research and Development, Pfizer Inc., Kalamazoo, MI 49001-0199, USA. steven.r.cox@pfizer.com, Lesman SP, Boucher JF, Krautmann MJ, Hummel BD, Savides M, Marsh S, Fielder A, Stegemann MR
Jazyk: angličtina
Zdroj: Journal of veterinary pharmacology and therapeutics [J Vet Pharmacol Ther] 2010 Oct; Vol. 33 (5), pp. 461-70.
DOI: 10.1111/j.1365-2885.2010.01165.x
Abstrakt: The pharmacokinetics of mavacoxib were evaluated in an absolute bioavailability study, a dose-proportionality study and a multi-dose study in young healthy adult laboratory Beagle dogs and in a multi-dose safety study in Beagle-sized laboratory Mongrel dogs. When administered as the commercial tablet formulation at 4 mg/kg body weight (bw) to fasted dogs, the absolute bioavailability (F) of mavacoxib was 46.1%; F increased to 87.4% when mavacoxib was administered with food. Following intravenous administration, the total body plasma clearance of mavacoxib was 2.7 mL·h/kg, and the apparent volume of distribution at steady-state was 1.6 L/kg. The plasma protein binding of mavacoxib was approximately 98% in various in vitro and ex vivo studies. The dose-normalized area under the plasma concentration-time curve was similar in Beagle and Beagle-sized Mongrel dogs when mavacoxib was administered with food. Mavacoxib exhibited dose-proportional pharmacokinetics for single oral doses of 2-12 mg/kg in Beagle dogs and for multiple oral doses of 5-25 mg/kg in Beagle-sized Mongrel dogs. Only minor accumulation occurred when mavacoxib was administered at doses of 2-25 mg/kg bw orally to laboratory dogs with a 2-week interval between the 1st two doses but with a monthly interval thereafter. Across all three Beagle studies (n = 63) the median terminal elimination half-life (t(½) ) was 16.6 days, with individual values ranging 7.9-38.8 days. The prolonged t(½) for mavacoxib supports the approved regimen in which doses are separated by 2-4 weeks.
(© 2010 Blackwell Publishing Ltd.)
Databáze: MEDLINE
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