N-desmethyl Enzalutamide is the active metabolite of Enzalutamide. Enzalutamide is an androgen-receptor (AR) antagonist with IC50 of 36 nM in LNCaP cells.
N-desmethyl Enzalutamide is an active metabolite that is thought to contribute to the clinical effects of Enzalutamide because it demonstrates primary and secondary pharmacodynamics of similar potency to Enzalutamide and circulates at approximately the same plasma concentrations as Enzalutamide. The carboxylic acid metabolite is pharmacologically inactive and circulates at approximately 25 % lower plasma concentrations than Enzalutamide[1].
[1]. Gibbons JA, et al. Pharmacokinetic Drug Interaction Studies with Enzalutamide. Clin Pharmacokinet. 2015 Oct;54(10):1057-69.