Abiraterone acetate and prednisolone for metastatic castration‐resistant prostate cancer failing androgen deprivation and docetaxel‐based chemotherapy: A phase II bridging study in Korean and Taiwanese patients

Abstract

Abbreviations & AcronymsObjectives: To evaluate the safety and efficacy of abiraterone acetate and prednisolone in Korean and Taiwanese patients with metastatic castration-resistant prostate cancer not responding to docetaxel-based chemotherapy. Methods: In this single-arm study, 82 metastatic castration-resistant prostate cancer patients who failed docetaxel-based chemotherapy were treated with abiraterone (1000 mg, once daily) and prednisolone (5 mg, twice daily). Patients achieving a prostate-specific antigen decline ≥50% were considered as responding. Results: A total of 35 patients (43%) achieved prostate-specific antigen response (95% confidence interval 32-54). The median time to prostate-specific antigen progression was 4.7 months (95% confidence interval 3.7-8.3); the median overall survival was 11.8 months. Two (4%) of 50 patients with measurable disease achieved partial response. The median testosterone concentration was in the castration range (1.21 nmol/L) throughout the treatment period. Median dehydroepiandrosterone sulfate decreased from 0.725 μmol/L (baseline) to 0.080 μmol/L (cycle 4). The most common adverse event was bone pain (20%); grade 3/4 adverse event of special interest were hypokalemia (7%), fluid retention and liver function abnormalities (5% each), hypertension (2%), and cardiac disorders (1%). Conclusions: A combination of abiraterone acetate and prednisolone appears to be a favorable second-line treatment in Taiwanese and Korean patients with advanced metastatic castration-resistant prostate cancer after failed docetaxel-based chemotherapy.

Abiraterone acetate for metastatic castration‐resistant prostate cancer after docetaxel failure: A randomized, double‐blind, placebo‐controlled phase 3 bridging study

“…Of note, the PSA response rate observed in the present study was slightly higher (49.7% vs 43%) in comparison with a phase 2 study in Korean and Taiwanese mCRPC patients under similar settings. 21 The positive treatment effects of abiraterone-prednisone were also consistent across specified patient subgroups, which included all age men and ECOG score of 0 or 1. Other results supporting the use of abiraterone acetate plus prednisone included a significant delay in pain progression and favorable effects on pain palliation rate among patients with a pain score of 4 or above.…”

Second-line Hormonal Therapy for the Management of Metastatic Castration-resistant Prostate Cancer: a Real-World Data Study Using a Claims Database

“…Fan et al reported a median OS with use of AA for treating chemotherapy-naive mCRPC patients of 23.3 months 16 . A study including Taiwanese and Korean patients reported a median OS of 11.8 months among 82 mCPRC patients with use of AA use after chemotherapy 17 . In the JPN-201 study, the 6-month survival rate www.nature.com/scientificreports www.nature.com/scientificreports/ was estimated to be 81% among patients receiving AA for mCRPC post-chemotherapy, compared to 98% in chemotherapy-naive mCRPC patients 18,19 .…”

Post hoc analyses of East Asian patients from the randomized placebo-controlled PREVAIL trial of enzalutamide in patients with chemotherapy-naïve, metastatic castration-resistant prostate cancer

“…Similar results were obtained in other studies of Asian men with mCRPC, including phase II studies of abiraterone acetate and prednisolone, in which 43% to 60% of Asian patients had a PSA response. [32,33] Similarly, in studies of cabazitaxel in Japanese [34] and Korean, [35] patients with mCRPC previously treated with chemotherapy, PSA responses were achieved by 29% and 32% of patients, respectively.…”