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

Abstract

Objectives: To evaluate the efficacy and safety of abiraterone acetate-prednisone versus placebo-prednisone in Asian metastatic castration-resistant prostate cancer patients who have failed docetaxel-based chemotherapy. Methods: In this double-blind, phase 3 study from China, 214 patients were randomized (2:1) to abiraterone acetate 1000 mg once daily plus prednisone 5 mg twice daily and placebo plus prednisone 5 mg twice daily in 28-day treatment cycles. Results: Abiraterone acetate-prednisone treatment significantly decreased prostate-specific antigen progression risk by 49%, with longer median time to prostate-specific antigen progression of 5.55 months versus 2.76 months in the placebo-prednisone group (hazard ratio 0.506, P = 0.0001, primary end-point). There was a strong trend for improved overall survival in the abiraterone acetate-prednisone group, with a 40% decrease in the risk of death (hazard ratio 0.604, P = 0.0597); however, median survival was not reached in either group because of the short follow-up period (12.9 months) and limited number of observed death events. The prostate-specific antigen response rate was higher in the abiraterone-prednisone group (49.7%) than in the placebo-prednisone group (14.1%). A total of 37.1% patients in this group had pain progression events compared with 50.7% in the placebo-prednisone group. Abirateroneprednisone significantly decreased the risk of pain progression by 50% (hazard ratio 0.496, P = 0.0014). The incidence of adverse events was similar between the two groups; the most common adverse events being anemia (25.9% for abiraterone-prednisone vs 22.5% for placebo -prednisone), hypokalemia (25.9% and 11.3%), bone pain (23.8% and 21.1%), hypertension (16.1% and 12.7%) and increased aspartate aminotransferase (14.7% and 15.5%), respectively. Conclusions: Abiraterone-prednisone significantly delays disease and pain progression, and prostate-specific antigen, with a favorable benefit-risk ratio in Asian metastatic castration-resistant prostate cancer patients in the post-docetaxel setting.

Targeting the androgenic pathway in elderly patients with castration-resistant prostate cancer

“…Nine studies [ 8–11 17–21 ] with 1970 cases in the antiandrogenic group and 1542 cases in the control group were included in the meta-analysis according to the inclusion and exclusion criteria described in the Materials and Methods Section (Fig. 1).…”

“…1). Six studies involved patients >75 years old, [ 10 11 17–20 ] while 2 studies [ 8 9 ] reported data on a subgroup analysis and regarded >70 years old men, one trial reported data on ≥65 years old men [21] . There were 5 postchemotherapy studies that included 1487 cases (917 in the experimental arm and 570 as control arm) and 4 prechemotherapy studies that included 2025 cases (1053 in the experimental arm and 972 as control arm).…”

“…The patient's characteristics were obtained for all studies. With regard to abiraterone, data has been obtained from 2 post hoc analysis of the COU-AA-301 and COU-AA-302 trial respectively [ 10 18 ] and a subgroup analysis [21] . With regard to enzalutamide, data have been obtained from a post hoc analysis of the AFFIRM and PREVAIL trials and from a subgroup analysis of TERRAIN and STRIVE trials.…”

Survival Benefits of Androgen Receptor Signaling-Axis Inhibitor’s at The Cost of Adverse Event Occurrence: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

“…From the 489 retrieved publications, we selected 84 potentially eligible articles for abstract and full articles review. Eventually 8 RCTs with 10 articles met the inclusion criteria [6][7][8][9][10][17][18][19][20][21] , which were published from 2012 to 2017(figure 1 and table 1). Two trials were phase 2, while six trials were phase 3.…”

Impact of abiraterone on patient-related outcomes in metastatic castration-resistant prostate cancer: current perspectives

“…A Phase III double-blind trial was held in China to evaluate the safety and tolerance of abiraterone in Asian patients with mCRPC after docetaxel failure 41. A total of 214 patients were randomized 2:1 to receive either abiraterone with prednisone or placebo with prednisone.…”