2-hydroxy Flutamide

2-hydroxy Flutamide is the major metabolite formed during the metabolism of the non-steroidal antiandrogen flutamide by cytochrome P450 (CYP) isoforms CYP1A2 and CYP3A4.{24727} Through competitive inhibition of the binding of testosterone to the nuclear androgen receptor (AR; IC50 = ~300-900), 2-hydroxy flutamide blocks the expression of AR target genes and prevents androgen-dependent stabilization of the AR.{24726} Compared to flutamide, 2-hydroxy flutamide is a more potent antiandrogen in vivo, demonstrating a higher binding affinity for the AR (0.1% binding affinity relative to dihydrotestosterone) and, thus, is the predominant contributor to the therapeutic effects of flutamide in the treatment of prostate cancer.{22432}