OBJECTIVES: Ra-223 is a first-in-class alpha emitter approved to treat castration-resistant prostate cancer and symptomatic bone metastases. In ALSYMPCA, Ra-223 significantly improved overall survival by 3.6 months vs placebo (HR=0.70; 95% CI, 0.58-0.83; P<0.001) and was well tolerated. We studied whether treatment benefit corresponds to differences in hospitalization and other health care resource use among European ALSYMPCA patients. METHODS: Data on hospitalization, nursing home visits, home health care and adult day care services use, and physician visits were captured for each patient. Treatment groups were compared based on percentage needing each health care resource (Fisher’s exact tests). To account for patients’ differences in resource use, the number and duration of encounters were divided by observation time and annualized, then compared (t-tests).  RESULTS: Mean follow-up times for Ra-223 vs placebo were 10.1 vs 8.5 months. Mean number of hospitalizations and hospitalization days/year for Ra-223 vs placebo were 1.3 vs 1.8 (P=0.009) and 8.6 vs 16.2 (P<0.001), respectively. The percentage of patients requiring hospitalization was lower for Ra-223 vs placebo (42.3% vs 51.8%; P=0.015). Among patients experiencing ≥1 hospitalization, mean number of hospitalization days/year for Ra-223 vs placebo patients were 20.8 vs 31.8 (P=0.002). Before a symptomatic skeletal event (SSE) was experienced, the number of hospitalization days/year was lower with Ra-223 vs placebo (5.9 vs 9.1 [P=0.039]). Similarly, after an SSE, the number of hospitalization days/year was lower with Ra-223 vs placebo (21.0 vs 40.9 [P=0.004]). No significant between-treatment-group differences were found in annual number of visits or time in nursing homes, amount of adult day care and home health care services used, and number of physician visits. CONCLUSIONS: Compared with placebo, Ra-223 treatment reduced the likelihood of needing hospitalization and number of hospitalizations/year; Ra-223–treated patients had about 7.6 fewer hospitalization days/patient/year.