The real-world efficacy of abiraterone acetate (ABA) and docetaxel (DOC) in the treatment of African-American (AA) patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC).

Abstract

52 Background: The landscape of mCSPC treatment changed with the addition of ABA and DOC. The prevalence of AA pts in the trials that led to these approvals was < 10%. We characterized the clinical outcomes (CO) of a cohort of AA pts treated with these agents. Methods: We retrospectively reviewed 51 AA pts with mCSPC treated with ABA or DOC at Grady Memorial Hospital from 2015-2018. The CO included median overall survival (mOS), progression-free survival (mPFS) and PSA response (PSAr) as defined by a ≥ 50% drop in PSA over the 1st 12 weeks of treatment. Cox proportional hazard model and Kaplan-Meier method were used for association with OS and PFS and logistic regression model for PSAr. Results: Median age was 63 years, 64% were grade group 5 and 67% had an ECOG status of 0-1. 82% had high volume disease per CHAARTED; 51% did per LATITUDE. 21 pts received ABA; 30 received DOC. The groups (ABA vs DOC) were balanced except for high volume disease per LATITUDE (28.6 vs. 66.7%) and lymph node metastases (66.7 vs. 96.7%). The DOC cohort received a mean of 5.2 cycles. Median follow-up was 10.3 months (mos). The overall mOS was 37.8 mos, mPFS was 10.3 mos, and PSAr was 89.6%. CO trended toward favoring ABA over DOC but did not differ significantly with a 12-month OS of 100% vs. 81.7% and PFS of 53.7% vs. 35.4%, respectively. Albumin and hemoglobin at baseline were associated with CO (Table). Conclusions: We present the first real world efficacy of ABA and DOC in a cohort of AA pts with mCSPC and found similar outcomes between the two groups. These findings warrant a larger study for validation.[Table: see text]