RU-59063 is a nonsteroidal antiandrogen (NSAA) drug that was never marketed. It is structurally related to other NSAAs like nilutamide, bicalutamide, and enzalutamide. RU-59063 possesses high affinity for the androgen receptor (AR) and acts as a potent competitive antagonist, blocking the effects of androgens like testosterone and dihydrotestosterone (DHT).
RU-59063 was developed by Roussel Uclaf, the same pharmaceutical company that developed mifepristone (RU-486). Research focused on its potential use in the treatment of androgen-dependent conditions, such as prostate cancer, benign prostatic hyperplasia (BPH), acne, and hirsutism. However, despite promising in vitro and in vivo studies, it did not progress beyond preclinical development. The reasons for its failure to reach market are not fully documented but likely involved a combination of factors including efficacy, safety, market considerations, and the presence of competing drugs already available or in development.
Like other NSAAs, RU-59063 competitively binds to the androgen receptor, preventing androgens from binding and activating it. This mechanism of action allows it to inhibit the growth of androgen-sensitive tissues and cancers. The absence of steroidal structure differentiates it from steroidal antiandrogens, such as cyproterone acetate.
Its chemical structure is C12H6F6N4O3. Further details on its synthesis and specific pharmacological profile are available in scientific literature related to antiandrogens and androgen receptor antagonists published during its development period. Because it was never marketed, information readily available to the general public is limited.