Author(s): Satoh T, Uemura H, Tanabe K, Nishiyama T, Terai A,
Abstract Share this page
Abstract OBJECTIVE: In this Phase 2 multicenter study the efficacy and safety of oral abiraterone acetate (1000 mg/once daily) plus prednisolone (5 mg/twice daily) was evaluated in metastatic castration-resistant prostate cancer patients from Japan who had previously received docetaxel-based chemotherapy. METHODS: Men (aged ≥20 years) with metastatic castration-resistant prostate cancer (prostate-specific antigen levels: ≥5 ng/ml), who had received 1 or 2 cytotoxic chemotherapies (with ≥1 regimen being docetaxel) for prostate cancer, were enrolled in this open-label, single-arm study. Primary efficacy endpoint was proportion of patients achieving a ≥50\% prostate-specific antigen decline from baseline (prostate-specific antigen response rate) after 12-week treatment. Safety and pharmacokinetics were also assessed. RESULTS: Confirmed prostate-specific antigen response rate by Week 12 was 28.3\% (90\% confidence interval: 17.6\%; 41.1\%) or 13 out of 46 (full analysis set) treated patients. However, total prostate-specific antigen response rate including confirmed and unconfirmed responses was 34.8\% (90\% confidence interval: 23.2\%; 47.9\%). Secondary efficacy endpoints and outcomes were: improvement in Eastern Cooperative Oncology Group performance status score by ≥1 unit: 7/16 patients (43.8\%); objective radiographic response: complete response, partial response and stable disease in 0, 1/22 (4.5\%) and 9/22 (40.9\%) patients, respectively; pain palliation response: 9/16 (56.3\%) patients. The most common adverse events (>20\% patients) were upper respiratory tract infection (13/47, 27.7\% patients) and hepatic function abnormal (10/47, 21.3\% patients, Grade 3: 8.5\%). All mineralocorticoid-related toxicities were Grade 1/2. CONCLUSIONS: Abiraterone acetate plus prednisolone showed favorable efficacy in metastatic castration-resistant prostate cancer Japanese patients who had received chemotherapy. Abiraterone acetate plus prednisolone had an acceptable safety profile. CLINICAL TRIAL REGISTRATION NO: NCT01795703. © The Author 2014. Published by Oxford University Press.
This article was published in Jpn J Clin Oncol
and referenced in Journal of Clinical Trials