Bone fractures and prior abiraterone use in men treated with radium-223 plus enzalutamide for castration-resistant prostate cancer with bone metastases: a real-world study

BACKGROUND/OBJECTIVES: To assess fracture risk in men with metastatic castration-resistant prostate cancer treated with radium-223 (Ra-223) plus enzalutamide and with prior abiraterone exposure. SUBJECTS/METHODS: We evaluated patients in the Komodo Health Research Dataset who started Ra-223 plus enzalutamide between January 2016 and December 2022. RESULTS: In total, 171 patients were identified; 15% developed fractures. Prior abiraterone did not increase fracture risk (OR 1.00; 95% CI 0.37-2.71), and bone health agents (BHAs) lowered fracture likelihood by 79% (OR 0.21; 95% CI 0.07-0.57; p = 0.010). CONCLUSIONS: In Ra-223 plus enzalutamide recipients, prior abiraterone was not associated with fractures and BHAs reduced fracture incidence.