(A) Progression-free survival (PFS), and (B) overall survival (OS) according to androgen receptor (AR) enhancer status in cell-free DNA (cfDNA). For PFS, median was 1.6 months in patients with AR enhancer altered and 9.1 months in patients with wild-type AR enhancer in cfDNA. For OS, median was not reached in either arm. Hazard ratio (HR) for PFS was 8.1 (95% CI, 2.8 to 23.6; P = .0001) and 16.4 (95% CI, 3.5 to 77.2; P = .0004) for OS. P values were calculated by the log-rank test and HRs by the Mantel-Haenszel method.