Final overall survival results from the EORTC 1333/PEACE-3 trial: Enzalutamide with or without radium-223 in metastatic castration-resistant prostate cancer.

15 Background: In EORTC1333.PEACE-3 the combination of enzalutamide and radium-223 (ENZ/RAD) prolonged rPFS and OS (interim analysis) in patients with mCRPC with bone metastases, with a safety similar to that of each treatment alone, versus enzalutamide alone (ENZ). Here we report the final OS analysis an updated safety data. Methods: EORTC1333/PEACE-3 is a randomized, open-label, multicentre phase III trial evaluating the addition of radium-223 (ENZ/RAD) to enzalutamide (ENZ) in metastatic castration-resistant prostate cancer (mCRPC) with bone metastases. In PEACE-3, a total of 446 asymptomatic or mildly symptomatic patients (Brief Pain Inventory 75, for which the interaction was significant at the 10% 2-sided level. The previously published primary analysis (Ann Oncol 2025) demonstrated a significant improvement in rPFS (19.4 vs 16.4 months; HR 0.69; 95% CI 0.54–0.87; p=0.0009). The final analysis consolidates these findings, confirming prolonged OS and no new safety signals. Conclusions: The final results of EORTC1333/PEACE-3 confirm that adding six cycles of radium-223 to enzalutamide significantly prolongs overall survival in men with bone-dominant mCRPC, supporting the synergistic potential of this combination. Detailed analyses of efficacy, safety, and subgroups will be presented. Clinical trial information: NCT02194842 .