Ralaniten triacetate (EPI-506), the pro-drug of Ralaniten, is a first-in-class, orally active androgen receptor (AR) N-terminal domain (NTD) inhibitor. Ralaniten triacetate shows activity against both full length and resistance-related AR species, including AR-v7[2].In Vitro: Ralaniten triacetate (EPI-506) targets the N-terminal domain of the androgen receptor (AR), and is used for metastatic castration-resistant prostate cancer (mCRPC) research. EPI-506 is a first-in-class, highly-specific small molecule that binds to a novel target on the AR, the N-terminal domain (NTD) and directly inhibits AR transcriptional activity by blocking the interaction of the AR with transcriptional proteins[2].