LBA-09 DAROLUTAMIDE DELAYS PROSTATE-SPECIFIC ANTIGEN PROGRESSION AND TIME TO NEXT ANTICANCER THERAPIES IN PATIENTS WITH NONMETASTATIC CASTRATION-RESISTANT PROSTATE CANCER

INTRODUCTION AND OBJECTIVES:Asymptomatic nonmetastatic castrate-resistant prostate cancer (nmCRPC) patients (pts) would benefit from treatments (Tx) that delay disease progression with minimal Tx-related adverse events (AEs). Darolutamide (DARO) is a structurally unique androgen receptor (AR) antagonist for which in vitro and phase I/II studies suggest low risk of AEs and drug-drug interaction. DARO prolonged metastasis-free survival (MFS) compared with placebo (PBO) (40 vs 18 mo; HR 0.41; 95% CI 0.34-0.50; P<0.001) in ARAMIS. Interim overall survival (OS) favored DARO (HR 0.71; 95% CI 0.50-0.99; P=0.045). DARO’s impact on prostate-specific antigen (PSA), disease progression, safety, and quality of life (QoL) in ARAMIS is reported here.METHODS:1509 pts were randomized 2:1 to DARO 600 mg (two 300 mg tablets) twice daily (n=955) or PBO (n=554) while continuing androgen deprivation therapy. The primary end point was MFS. Secondary and exploratory endpoints included OS, time to cytotoxic chemotherapy, time to...