Abstract
1. (1S)-1-phenyl-2-(pyridin-2-yl)ethanamine (lanicemine; AZD6765) is a low-trapping N-methyl-d-aspartate (NMDA) channel blocker that has been studied as an adjunctive treatment in major depressive disorder. The metabolism and disposition of lanicemine was determined in six healthy male subjects after a single intravenous infusion dose of 150 mg [14C]-lanicemine.
2. Blood, urine and feces were collected from all subjects. The ratios of Cmax and AUC(0–∞) of lanicemine to plasma total radioactivity were 84 and 66%, respectively, indicating that lanicemine was the major circulating component with T1/2 at 16 h. The plasma clearance of lanicemine was 8.3 L/h, revealing that lanicemine is a low-clearance compound. The mean recovery of radioactivity from urine was 93.8% of radioactive dose.
3. In urine samples, 10 metabolites of lanicemine were identified. Among which, an O-glucuronide conjugate (M1) was the most abundant metabolite (∼11% of the dose in excreta). In plasma, the circulatory metabolites were identified as a para-hydroxylated metabolite (M1), an O-glucuronide (M2), an N-carbamoyl glucuronide (M3) and an N-acetylated metabolite (M6). The average amount of each of metabolite was less than 4% of total radioactivity detected in plasma or urine.
4. In conclusion, lanicemine is a low-clearance compound. The unchanged drug and metabolites are predominantly eliminated via urinary excretion.
Acknowledgements
The authors acknowledge Quintiles Drug Research Unit at Guy’s Hospital (London, UK) for conduct of the clinical mass balance study; Covance Laboratories (Harrogate, UK) for determination of [14C] radioactivity in whole blood, plasma, urine and feces; BASi (US) for determination of concentration of lanicemine in human plasma and urine; and other colleagues for their contributions to this study.
Declaration of interest
This study was sponsored by AstraZeneca Pharmaceuticals.