Efficacy of eplerenone (Epe) in the management of mineralocorticoid excess (MCE) in men with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone (AA) without prednisone (P).

Abstract

261 Background: AA is approved for Mcrpc with co-administration with P to prevent MCE toxicity such as hypertension, hypokalemia and edema. However, use of P is often not desirable by the relatively asymptomatic patients because of potential for detrimental effects of long term corticosteroid therapy. Epe is a non-steroidal mineralocorticoid antagonist demonstrated to abrogate MCE. Here we report real world experience of use of Epe with AA in men with mCRPC who wished to avoid concomitant P. Methods: Incidence and grade (CTCAE v4) of MCE, along with baseline demographics, disease characteristics, and progression free survival (PFS) in men with mCRPC treated with AA (1000 mg daily), not willing to be treated with P (and thus received treatment with Epe 50 mg daily) were collected retrospectively, and compared with those treated with AA + P (10 mg daily) during the same time period (Table). Continuous variables were assessed by Wilcoxon rank sum or student t-test, and categorical variables were assessed by Fischer’s Exact test or chi-square as appropriate. PFS was compared by Kaplan-Meier. Results: Baseline and disease characteristics, median PFS, and toxicities of all grades were similar in both cohorts (Table). Conclusions: In real world population of men with mCRPC treated with AA, corticosteroids may be avoided by concomitant treatment with Epe. Data need further validation in a larger cohort. [Table: see text]