Abacavir

Absorption	Rapid and extensive after oral administration (83% bioavailability)
Volume of distribution	0.86 ± 0.15 L/kg
Protein binding	Moderate (approximately 50%)
Metabolism	Hepatic, by alcohol dehydrogenase and glucuronosyltransferase to a 5′-carboxylic acid metabolite and 5′-glucuronide metabolite, respectively. These metabolites have no antiviral activity. Abacavir is not significantly metabolized by cytochrome P450 enzymes.
Route of elimination	Elimination of abacavir was quantified in a mass balance study following administration of a 600-mg dose of 14C-abacavir: 99% of the radioactivity was recovered, 1.2% was excreted in the urine as abacavir, 30% as the 5′-carboxylic acid metabolite, 36% as the 5′-glucuronide metabolite, and 15% as unidentified minor metabolites in the urine. Fecal elimination accounted for 16% of the dose. Fecal elimination accounted for 16% of the dose. Renal excretion of unchanged abacavir is a minor route of elimination in humans.
Half life	1.54 ± 0.63 hours
Clearance	0.80 +/- 0.24 L/hr/kg [asymptomatic, HIV-1-infected adult patients receiving single (IV dose of 150 mg]
Toxicity	Some myocardial degeneration has been noticed in rats and mice
Affected organisms	Human Immunodeficiency Virus
Pathways	Not Available