Euricstat Mechanism of Action

Pharmacology: Pharmacodynamics: Febuxostat is a xanthine oxidase inhibitor that achieves its therapeutics effect by decreasing serum uric acid. Febuxostat is not expected to inhibit other enzymes involved in purine and pyrimidine synthesis and metabolism at therapeutic concentrations.
Pharmacokinetics: Absorption: The absorption of radiolabeled Febuxostat following oral dose administration was estimated to be at least 49%. Maximum plasma concentrations of Febuxostat occurred between 1 and 1.5 hours post-dose. Absolute bioavailability of Febuxostat tablet has not been studied.
Distribution: The mean apparent steady state of volume of distribution of Febuxostat was approximately 50L. While the plasma protein binding is approximately 99.2% (primarily to albumin).
Metabolism: Febuxostat is extensively metabolized by both conjugation via uridine diphosphate glucuronosyltransferase (UGT) enzymes including CYP1A2, 2C8 and 2C9 and non P-450 enzymes. The relative contribution of each enzyme isoform in the metabolism of Febuxostat is not clear. The oxidation of the isobutyl side chain leads to the formation of four pharmacologically active hydroxy metabolites, all of which occur in plasma of humans at a much lower extent than Febuxostat.
In urine and feces, acyl glucuronide metabolites of Febuxostat and oxidative metabolites, 67M-1, 67M-2 and 67M-4, a secondary metabolite from 67M-1 appeared to be the major metabolites of Febuxostat in vivo.
Elimination: Febuxostat is eliminated by both hepatic and renal pathways. The apparent mean terminal elimination half-life (t¹/₂) of Febuxostat was approximately 5-8 hours.