Relation Between Blood Concentration of Colchicine and Response to Colchicine Treatment in Gout Flare

Gout, secondary to sodium urate crystal deposition, is responsible of recurrent inflammatory painful flares. Efficacy of colchicine which is the first line drug for the treatment and prophylaxis of gout flare varies and only half of treated patients experience good response. This study aims to optimize colchicine prescription for the treatment and prophylaxis of gout flare. Current data suggest that efficiency of colchicine relies on its maximum blood concentration (Cmax). In this study, the investigators hypothesize that responders to colchicine treatment have higher colchicine Cmax than non-responder patients following the recommended dose regimen (1 mg then 0.5 mg 1 hour later). The individual pharmacokinetics (PK) of colchicine remains poorly investigated while the assessment of individual drug metabolisms can be performed. The hypothesis of this study stands that several factors contribute to the variability of colchicine Cmax. The analysis of individual PK profile and a well-characterized metabolism of colchicine will permit a personalized treatment regimen for the treatment and prophylaxis of gout flares.