Discovery of LYA914, An Orally Bioavailable PROTAC Degrader Targeting the DNA Binding Domain of the Androgen Receptor for the Treatment of CRPC

Prostate cancer is a common male malignancy. Although androgen deprivation therapy (ADT) is initially effective, it often leads to castration-resistant prostate cancer (CRPC) eventually. Second-generation androgen antagonists are the standard therapy for CRPC. However, resistance develops due to mutations or splice variants in the ligand binding domain (LBD) of the androgen receptor (AR). Therefore, the development of novel, efficient, and safe therapeutic agents for CRPC is of great significance. In this study, we designed and synthesized compound LYA914 as a proteolysis-targeting chimera (PROTAC) degrader targeting the conserved DNA binding domain (DBD) of AR, which can simultaneously degrade AR and its variant AR-V7. It demonstrated effective antiproliferative effects in enzalutamide-insensitive/resistant cells. In a VCaP castrated tumor cell model, oral administration of LYA914 obviously inhibited tumor growth, demonstrating superior efficacy compared to enzalutamide. These findings underscore the promising potential of LYA914 for the treatment of CRPC.