The metabolism and excretion of the dipeptidyl peptidase 4 inhibitor [C-14] cetagliptin in healthy volunteers

The metabolism and excretion of cetagliptin were investigated in healthy male subjects after a single oral dose of 100mg/50 mu Ci [C-14] cetagliptin. The mean concentration-time profile of cetagliptin was similar to that of total radioactivity in plasma after oral administration of [C-14] cetagliptin in healthy male subjects. Cetagliptin was rapidly absorbed after oral administration. Unchanged cetagliptin was the most abundant radioactive component in all matrices investigated. Approximately 53.13% of plasma AUC of total radioactivity was accounted for by cetagliptin. Each metabolite plasma AUC was not higher than 2.93% of plasma AUC of total radioactivity. By 336 h after administration, 91.68% of the administered radioactivity was excreted, and the cumulative excretion in the urine and faeces was 72.88% and 18.81%, respectively. The primary route of excretion of radioactivity was via the kidneys. Four metabolites were detected at trace levels, and it involved hydroxylated (M436-1 and M436-3), N- sulphate (M500), and N-carbamoyl glucuronic acid conjugates (M640B) of cetagliptin. These metabolites were detected also in plasma, urine, and faeces at low levels, except that metabolite M640B was not detected in faeces. All metabolites were observed with