Routes of
administration Oral PubChem CID 11188409 UNII WA33E149SW | CAS Number 851983-85-2 ChemSpider 9363493 KEGG D10125 | |
 | ||
Galeterone (TOK-001 or VN/124-1) is a novel steroidal antiandrogen under development by Tokai Pharmaceuticals for the treatment of prostate cancer. It possesses a unique dual mechanism of action, acting as both an androgen receptor antagonist and a CYP17A1 inhibitor, the latter of which prevents the biosynthesis of androgens. As a CYP17A1 inhibitor, galeterone shows selectivity for 17,20-lyase over 17α-hydroxylase.
Galeterone was being compared to enzalutamide in a phase III clinical trial (ARMOR3-SV) for AR-V7-expressing metastatic castration-resistant prostate cancer. Tokai announced the discontinuation of ARMOR3-SV on July 26, 2016, after a data monitoring committee determined that the trial was unlikely to meet its endpoint. On August 22, 2016, the company announced the discontinuation of their phase II expansion (ARMOR2) as well.