TABLE 4

Quantitation of varenicline and major metabolites in circulation of mice, rats, monkeys, and humans after oral administration of [14C]varenicline


Metabolite (M + H+ ion)

Mouse

Rat

Monkey

Human
% circulating radioactivity
M1 (amino acid metabolite; m/z 244) 1.4 N.D. N.D. N.D.
M2 (amino acid metabolite; m/z 244) 3.8 0.7 1.7 N.D.
M3a unknown 1.1 N.D. 0.53 N.D.
M3c (putative lactam; m/z 226) N.D. N.D. 0.93 1.1
Varenicline (m/z 212) 85 81 80 91
M3d (putative lactam; m/z 226) 6.8 N.D. 2.1 N.D.
M4 (varenicline N-carbamoylglucuronide; m/z 432) N.D. 11 8.7 3.8
M5 (N-formylvarenicline; m/z 240) 2.5 5.3 2.6 0.9
M6 unknown N.D. 1.7 N.D. N.D.
M7 (N-glucosylvarenicline; m/z 374)
N.D.
1.2
2.9
3.5
  • N.D., not detected.