PURPOSE: DARO is a structurally distinct androgen receptor antagonist for which in vitro and phase 1/2 studies suggest low risk of adverse events (AEs) and drug–drug interaction. In the ARAMIS study of DARO in nmCRPC, metastasis-free survival (MFS) was significantly prolonged vs placebo (PBO) (40.4 vs 18.4 mo; hazard ratio [HR] 0.41; 95% confidence interval [CI] 0.34–0.50; P < 0.001) and interim overall survival (OS) favored DARO (HR 0.71; 95% CI 0.50–0.99; P = 0.045).
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 (ADT). Primary endpoint was MFS. Secondary endpoints included OS and time to pain progression. QoL was assessed by EORTC-QLQ-PR25 at baseline (BL) and every 16 wks until end of treatment. Analysis of time to deterioration (TTD) in EORTC-QLQ-PR25 subscales, defined as first occurrence of a minimally important difference.
RESULTS: DARO significantly delayed pain progression vs PBO (40.3 vs 25.4 mo; HR 0.65; 95% CI 0.53–0.79; P < 0.001); this was maintained beyond end of study treatment. TTD showed statistically and clinically significant delays with DARO vs PBO for urinary symptoms (25.8 vs 14.8 mo; HR 0.64; 95% CI 0.54–0.76; P < 0.01). TTD of hormonal treatment-related symptoms was comparable with DARO vs PBO (18.9 vs 18.4 mo; HR 1.06; 95% CI 0.88–1.27; P = 0.52). DARO was well tolerated. Exposure-adjusted incidences of AEs of interest were similar/lower with DARO vs PBO (fatigue/asthenic conditions [11.3 vs 11.1], hypertension [4.7 vs 5.1], hot flush [3.7 vs 4.1], fracture [3.0 vs 3.5], falls [2.7 vs 4.1], cognitive disorder [0.3 vs 0.2], and seizure [0.2 vs 0.2]).
CONCLUSIONS: For nmCRPC pts, DARO prolongs MFS, is well tolerated, maintains QoL, and delays worsening of pain and disease-related symptoms compared with PBO.
