Association between major cardiovascular events and abiraterone acetate compared to enzalutamide in patients with metastatic castration-resistant prostate cancer: a post hoc analysis of the EVADE study

Purpose: This study investigated the risk of major cardiovascular (CV) events in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate (AA) versus enzalutamide (ENZA); assessed treatments for prostate cancer (PC), focusing on corticosteroid-containing regimens; and examined comorbidities recorded in primary and secondary care. Methods: This was a post hoc analysis of the retrospective, observational EVADE study in patients who received AA or ENZA for mCRPC. Patient characteristics at treatment initiation were described, focusing on characteristics affecting the risk of CV events, together with PC treatments in the entire PC pathway. Major CV event risk was assessed with Cox regression after adjustment with inverse probability of treatment weighting (IPTW). Results: Overall, 1,382 patients were included (AA: 556; ENZA: 826). After IPTW adjustment, risk of a major CV event was 65.0% higher in the AA versus the ENZA group (hazard ratio: 1.65; 95% confidence interval: 1.27, 2.14; P = 0.0001). Across the entire patient pathway, the average time on corticosteroid-containing PC regimens was 298 days versus 72 days for the AA versus ENZA group. While type 2 diabetes was less frequently reported in secondary versus primary care (59.8% vs. 94.9%), CV comorbidities were more frequently reported (87.1% vs. 84.2%). Conclusion: Major CV event risk was significantly higher in the AA versus ENZA group, and the AA group had numerically greater exposure to corticosteroid-containing PC regimens over the treatment course. There were discrepancies in recording diabetes and CV comorbidities between primary and secondary care in England.