Nilutamide-d6 is intended for use as an internal standard for the quantification of nilutamide by GC- or LC-MS. Nilutamide is a non-steroidal antiandrogen that is an antagonist of the androgen receptor.1 It reverses testosterone-induced increases in cell proliferation with an IC50 value of 412 nM in mouse mammary carcinoma cells in vitro.2 It has antiandrogenic activity in both intact and castrated rats, inhibiting testosterone propionate-induced prostate growth when administered at a dose of 2.5 mg/kg.3 Formulations containing nilutamide have been used in combination with surgical castration in the treatment of metastatic prostate cancer.

|1. Signh, S.M., Gauthier, S., and Labrie, F. Androgen receptor antagonists (antiandrogens): Structure-activity relationships. Curr. Med. Chem. 7(2), 211-247 (2000).|2. Simard, J., Singh, S.M., and Labrie, F. Comparison of in vitro effects of the pure antiandrogens OH-flutamide, Casodex, and nilutamide on androgen-sensitive parameters. Urology 49(4), 580-586 (1997).|3. Wakeling, A.E., Furr, B.J.A., Glen, A.T., et al. Receptor binding and biological activity of steroidal and nonsteroidal antiandrogens. J. Steroid Biochem. 15, 355-359 (1981).