This secondary analysis of two STAMPEDE phase 3 trials evaluated whether abiraterone-based treatment intensification (SOC+AAP ± enzalutamide) increased fracture-related hospitalisation (FRH) compared to standard of care (SOC) alone in 3,102 patients with newly diagnosed high-risk non-metastatic (M0) or metastatic (M1) prostate cancer in England, with up to 5-year follow-up.
In M1 disease, 5-year FRH incidence was **lower** with SOC+AAP vs. SOC alone (22% vs. 30%; SDHR 0.77, 95% CI 0.59–0.99; p=0.04), and lower still with SOC+AAP+Enza vs. SOC alone (28% vs. 38%; SDHR 0.69, 95% CI 0.54–0.88; p=0.002); no significant difference was seen in M0 patients.
- Only hospitalised fractures were captured, likely **underestimating** total fracture burden. - No baseline bone mineral density or fracture-risk assessment was available. - Longitudinal bone-protective therapy use was not systematically recorded, which may confound results.
Clinicians can reassure patients with metastatic prostate cancer that abiraterone-based intensification does not increase — and may actually reduce — fracture-related hospitalisation, likely through better control of bone metastases. Bone-protective strategies remain important, but ARPI-related fracture risk concerns should not deter treatment intensification in M1 disease.
