UBX-103

UBX-103 is an orally bioavailable small molecule proteolysis-targeting chimera (PROTAC) designed to degrade the androgen receptor (AR). Developed by Ubix Therapeutics and out-licensed to Yuhan for further development and commercialization, it targets metastatic castration-resistant prostate cancer (mCRPC). Preclinical data show that UBX-103 achieves potent AR degradation at picomolar concentrations (DC50), demonstrates efficacy against a broad spectrum of treatment-induced resistance mutations, and inhibits tumor growth resistant to next-generation hormonal therapies. The drug leverages targeted protein degradation technology to inactivate disease-causing pathways by harnessing the body’s natural protein degradation machinery[3][5][6][8][10].