According to the finding of three studies presented at the Genitourinary Cancer Symposiom, statins may improve overall survival among men with metastatic castration-resistant prostate cancer (mCRPC) and improve cancer-specific survival among those with high-risk prostate cancer (PCa).
In a post-hoc analysis of data from the randomized clinical trials COU-AA-301 and COU-AA-302, in which men with mCRPC were treated with prednisone plus placebo or abiraterone, researchers found that statin users had significantly better overall survival than non-users.
The reference group for both studies included patients in the placebo arm who did not use statins. Among statin users in the COU-AA-301 study, patients treated with prednisone plus abiraterone had a significant 29% decreased risk of death compared with the reference group. The investigators observed no significant decrease in death risk among statin users in the placebo arm.
In the COU-AA-302 study, statin users in the abiraterone and placebo groups had a significant 28% and 19% decreased risk of death, respectively, compared with the reference group.
In a completely separate study, researchers examined the effect of statin use on outcomes among patients with mCRPC receiving abiraterone, an anti-androgen that inhibits CYP17A1. Their analysis included 301 patients. Of these, 84 (28%) were statin users. The median overall survival for statin users and non-users was 16.2 and 11.3 months, a borderline significant difference in adjusted analyses.
The study authors concluded: “Although limited by sample size, our data showed a trend that statins may mildly enhance the anti-tumor effects of [abiraterone] in CRPC patients.”
The findings suggest that depletion of de novo cholesterol production may further limit androgen synthesis in concert with CYP17A1 inhibition.
In a population-based study of 12,700 men with high-risk PCa identified using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database, researchers found that post-diagnostic use of statins is associated with a 47% lower risk of PCa mortality compared with patients with no documented statin use. Among obese patients, statin use was associated with a 62% decreased risk of PCa mortality. The investigators observed a synergistic effect of statins and metformin among patients with metastatic disease.