Abiraterone in metastatic castration-resistant prostate cancer: Efficacy and safety in unselected patients

Background: Abiraterone acetate (AA), an androgen biosynthesis inhibitor, is now a standard of care for men with metastatic, castration-sensitive and castration-resistant prostate cancer (mCRPC). Data exploring real-world toxicity and outcomes are scarce. Methods: Retrospective study on unselected patients with mCRPC on AA plus steroids. Results: 93 patients were included in the study. Median duration of treatment by AA was 7.5 months (95% CI 5.7–12) among the 58 patients pretreated with chemotherapy, versus 12.7 months (95% CI 8.2–35.9) among the 33 chemo-naive patients. Median survivals would reach 13.4 months (95% CI 10.2–19.1) and 36.4 months (95% CI 24.7–41.5) respectively. Rates of hypokalemia, peripheral edema, hypertension, cardiac failure, and overall survival assessments in patients with and without prior chemotherapy were similar to that previously reported in phase 3 randomized trials. The median survival time without adverse event of special interest was 7.5 months for hypokalemia and hypertension, and 5.3 months for liver-function test abnormalities (it was not reached for cardiac disorders). Conclusion: Our findings provide further evidence for the survival benefits of AA with a low frequency of additional adverse events among unselected patients. In patients who have not developed hypokalemia or a transaminase increase within 7.5 and 5.3 months respectively, a lighter systematic monitoring may be considered.