An abstract of this work was presented at the American College of Veterinary Internal Medicine (ACVIM) Forum in Anaheim, CA, June 2010.
Pharmacokinetics of ganciclovir and valganciclovir in the adult horse
Article first published online: 10 JAN 2013
© 2013 John Wiley & Sons Ltd
Journal of Veterinary Pharmacology and Therapeutics
Volume 36, Issue 5, pages 441–449, October 2013
How to Cite
Pharmacokinetics of ganciclovir and valganciclovir in the adult horse. J. vet. Pharmacol. Therap. 36, 441–449., ,
- Issue published online: 6 SEP 2013
- Article first published online: 10 JAN 2013
- Manuscript Accepted: 2 NOV 2012
- Manuscript Received: 12 JAN 2012
- Grayson Jockey Club
- National Institutes of Health. Grant Number: NIH T35RR007061
- the Center for Veterinary Health Sciences Short-Term Training Program
Equine herpes myeloencephalopathy, resulting from equine herpes virus type 1 (EHV-1) infection, is associated with substantial morbidity and mortality in the horse. As compared to other antiviral drugs, such as acyclovir, ganciclovir has enhanced potency against EHV-1. This study investigated the pharmacokinetics of ganciclovir and its oral prodrug, valganciclovir, in six adult horses in a randomized cross-over design. Ganciclovir sodium was administered intravenously as a slow bolus at a dose of 2.5 mg/kg, and valganciclovir was administered orally at a dose of 1800 mg per horse. Intravenously administered ganciclovir disposition was best described by a three-compartment model with a prolonged terminal half-life of 72 ± 9 h. Following the oral administration of valganciclovir, the mean observed maximum serum ganciclovir concentration was 0.58 ± 0.37 μg/mL, and bioavailability of ganciclovir from oral valganciclovir was 41 ± 20%. Superposition predicted that oral dosing of 1800-mg valganciclovir two times daily would fail to produce and maintain effective plasma concentrations of ganciclovir. However, superposition suggested that i.v. administration of ganciclovir at 2.5 mg/kg every 8 h for 24 h followed by maintenance dosing of 2.5 mg/kg every 12 h would maintain effective ganciclovir serum concentrations in most horses throughout the dosing interval.