UK real-world data of radium-223 dichloride in metastatic prostate cancer.

[OBJECTIVES] To evaluate the treatment patterns and outcomes in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with radium-223 dichloride in the UK.

[METHODS] Patients initiating treatment with radium-223 from 1 September 2017 to 1 September 2019 in 15 UK oncology centres were included. Demographics, treatment, clinical, biochemical, and outcome data were collected prospectively. Quality of life data were obtained using analgesic scores and components of the Functional Assessment Cancer Therapy - Prostate (FACT-P) questionnaire.

[RESULTS] A total of 550 consecutive, evaluable patients were included. The most common prior therapy for mCRPC was enzalutamide. At final analysis, after a median follow-up of 13.3 months, 55% of patients had completed six cycles of treatment. Median overall survival was 13.7 months (95% confidence interval, 12.6-14.8 months). Poor performance status, prior use of docetaxel in the metastatic hormone sensitive prostate cancer (mHSPC) setting, number of lines of prior treatment, and abnormal platelet count were independent variables associated with poor prognosis. Adverse events led to treatment discontinuation in 5.5% of patients. WHO analgesic scores and FACT-P questionnaire scores did not significantly change after treatment administration.

[CONCLUSION] The National Radium-223 Dichloride Audit was the first and largest multicentre prospective analysis of treatment patterns, outcomes, and quality of life data in patients treated with radium-223 in the UK. Radium-223 can be administered safely to patients previously treated with other life-prolonging therapies. Efficacy and safety data compare favourably with clinical trial and other real-world data. Our results suggest that its use earlier in the treatment pathway is associated with longer survival.