Effect of abiraterone acetate treatment on the quality of life of patients with metastatic castration-resistant prostate cancer after failure of docetaxel chemotherapy

Background: In a recent randomised, double-blind, phase III clinical trial among 1195 patients with metastatic castration-resistant prostate cancer (mCRPC) who had failed docetaxel chemotherapy, abiraterone acetate was shown to significantly prolong overall survival compared with prednisone alone. Here we report on the impact of abiraterone therapy on the health-related quality of life (HRQoL) observed during this trial, assessed using the validated Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire. Methods: All analyses were conducted using prespecified criteria for clinically meaningful improvement and deterioration in FACT-P total score as well as subscale scores; all respective thresholds were defined using an accepted methodology. Improvement was assessed only in patients with clinically significant functional status impairment at baseline. Results: Significant improvements in the FACT-P total score were observed in 48% of patients receiving abiraterone versus 32% of patients receiving prednisone (p < 0.0001). Also, the median time to deterioration in FACT-P total score was longer (p < 0.0001) in patients receiving abiraterone (59.9 weeks versus 36.1 weeks). Similar differences were observed in all FACT-P subscales, with the exception of the social/family well-being domain. Median time to improvement in the physical well-being domain and the trial outcome index was significantly shorter (p < 0.01) with abiraterone when compared with the prednisone arm. Conclusions: The previously demonstrated survival benefit for abiraterone is accompanied by improvements in patient-reported HRQoL and a significant delay in HRQoL deterioration when compared with prednisone.