Nationwide population-based study on the use of novel antiandrogens in men with prostate cancer in Sweden

Objectives: The aim of this study was to examine the use of abiraterone and enzalutamide, two oral novel antiandrogens (NOVAs), in men with prostate cancer (PCa) in Sweden.

Materials and methods: This cross-sectional study investigated filled prescriptions for NOVAs recorded in the Swedish Prescribed Drug Register between July 2015 and April 2016. Associations between age, comorbidity, educational level, marital status and county of residence and filled prescriptions were analyzed in the National Prostate Cancer Register (NPCR) and other health population-based registers, using multivariable logistic regression.

Results: Of 91,209 men, 1650 (2%) had at least one prescription filled for NOVAs, of whom 1350 (82%) had high-risk or metastatic PCa at diagnosis.. Of 1914 men with M1 disease and a high probability of castration-resistant prostate cancer (CRPC), 22% had a prescription for NOVAs at a median 3 years after the date of diagnosis. At multivariable logistic regression analysis,, the likelihood of NOVA use was lower in older men [age >80 vs <70 years: odds ratio (OR) 0.23, 95% confidence interval (CI) 0.15–0.35] and in men with lower educational level (high vs low education: OR 1.64, 95% CI 1.23–2.20). There was up to a five-fold difference in the use of NOVAs between county councils.

Conclusions: Less than one-third of potentially eligible men with CRPC received NOVAs in 2015–2016. There were large differences in use according to age and region of residence, indicating that efforts are needed to improve equal access to novel cancer drugs.