Darolutamide versus abiraterone acetate-based triplets in patients with hormone-sensitive prostate cancer: real-world, head-to-head comparison from the ARON-3 study

BACKGROUND: The therapeutic landscape of metastatic hormone-sensitive prostate cancer (mHSPC) has expanded significantly with triplet regimens, raising questions about their real-world applicability. This study evaluates the efficacy and safety of darolutamide- and abiraterone-based triplets using real-world data from the ARON-3 study. METHODS: A retrospective analysis was conducted on 247 mHSPC patients treated with DARO+DOCE+ADT or ABI+DOCE+ADT across 37 institutions in 14 countries. Key outcomes included progression-free survival (PFS), overall survival (OS), PSA kinetics, and safety. A propensity score was estimated based on key clinical variables and included as a covariate in Cox regression models to adjust for baseline imbalances between treatment groups. RESULTS: Data from 247 patients receiving triplet therapy were analyzed. The median OS for the entire cohort was not reached (NR). The median PFS was 24.8 months (95% CI: 18.7-33.6), with NR for DARO+DOCE+ADT and 21.5 months (95% CI: 13.1-25.2) for ABI+DOCE+ADT (P=0.007). In patients with visceral metastases, DARO+DOCE+ADT demonstrated superior outcomes, achieving higher OS rates at 6 months (97% vs. 83%, P=0.002) and 12 months (92% vs. 74%, P<0.001) compared to ABI+DOCE+ADT. The safety profiles of both regimens were comparable, although grade 3-4 fatigue was more frequently observed in the ABI+DOCE+ADT group. After adjusting for baseline imbalances through propensity score inclusion in multivariate models, the differences in OS (P=0.103) and PFS (P=0.135) between treatment groups did not reach statistical significance, although a numerical trend favoring DARO+DOCE+ADT was observed. CONCLUSIONS: Both regimens demonstrate efficacy, with DARO+DOCE+ADT offering superior outcomes in high-volume disease, especially visceral metastases. Nonetheless, the limited sample size and potential biases highlight the need for further follow-up and biomarker-driven studies in larger cohorts to refine treatment strategies.