In vitro metabolism of CP-122,721 ((2S,3S)-2-phenyl-3-[(5-trifluoromethoxy-2-methoxy)benzylamino]piperidine), a non-peptide antagonist of the substance P receptor.

The metabolism of CP-122,721, a neurokinin-1 antagonist, has been examined in vitro using hepatic microsomes from human and animal species, and recombinant heterologously expressed P450 enzymes. Metabolism occurs primarily via O-demethylation and N-dealkylation reactions. In human liver microsomes, O-demethylation was shown to be catalyzed by CYP2D6 with a low K(M) value.