Yujiro Ueda1, Nobuaki Matsubara2, Itsuhiro Takizawa3, Tsutomu Nishiyama3, Ken-Ichi Tabata4, Takefumi Satoh4, Naoto Kamiya5, Hiroyoshi Suzuki5, Takashi Kawahara6, Hiroji Uemura6. 1. Department of Breast and Medical Oncology, National Cancer Center Hospital East, Chiba. 2. Department of Breast and Medical Oncology, National Cancer Center Hospital East, Chiba nmatsuba@east.ncc.go.jp. 3. Division of Urology, Department of Regenerative and Transplant Medicine, Graduate School of Medical and Dental Sciences, Niigata University, Niigata. 4. Department of Urology, Kitasato University School of Medicine, Kanagawa. 5. Department of Urology, Toho University Sakura Medical Center, Chiba. 6. Department of Urology, Yokohama City University Graduate School of Medicine, Kanagawa, Japan.
Abstract
OBJECTIVE: Abiraterone acetate and docetaxel are promising treatment options for metastatic castration-resistant prostate cancer patients. However, the optimal sequencing of these agents is unclear, and no previous reports discuss Japanese metastatic castration-resistant prostate cancer patients. The purpose of this analysis is to reveal the outcomes of Japanese metastatic castration-resistant prostate cancer patients treated with abiraterone acetate followed by docetaxel. METHODS: We retrospectively reviewed Japanese Phase 1 and Phase 2 trials of metastatic castration-resistant prostate cancer patients treated with abiraterone acetate until disease progression and subsequently treated with docetaxel. The primary outcome measure was the rates of prostate-specific antigen declines ≧30 and ≧50%, respectively, with docetaxel. Secondary outcome measures included progression-free survival with docetaxel, and overall survival after initiation of abiraterone acetate and docetaxel. We performed correlation analysis between previous prostate-specific antigen response to abiraterone acetate and subsequent prostate-specific antigen response to docetaxel. RESULTS: We identified 15 patients had experienced disease progression with abiraterone acetate and subsequently were treated with docetaxel. Prostate-specific antigen declines ≧30 and ≧50% with docetaxel were observed in five patients (33%) and two patients (13%), respectively. The median progression-free survival with docetaxel was 3.7 months (95% confidence interval: 2.9-4.6). The median overall survival from initiation of docetaxel and abiraterone acetate were 14.4 months (95% confidence interval: 6.3-22.4), and 25.7 months (95% confidence interval: 20.1-30.7), respectively. No significant correlation was observed between these prostate-specific antigen responses (Pearson r = 0.206, P = 0.46). CONCLUSION: The efficacy of docetaxel in Japanese mCRPC patients that was resistant to abiraterone acetate was modest. The prostate-specific antigen response to previous abiraterone acetate could not predict the efficacy of subsequent docetaxel. Larger prospective trials are needed to validate these findings.
OBJECTIVE:Abiraterone acetate and docetaxel are promising treatment options for metastatic castration-resistant prostate cancerpatients. However, the optimal sequencing of these agents is unclear, and no previous reports discuss Japanese metastatic castration-resistant prostate cancerpatients. The purpose of this analysis is to reveal the outcomes of Japanese metastatic castration-resistant prostate cancerpatients treated with abiraterone acetate followed by docetaxel. METHODS: We retrospectively reviewed Japanese Phase 1 and Phase 2 trials of metastatic castration-resistant prostate cancerpatients treated with abiraterone acetate until disease progression and subsequently treated with docetaxel. The primary outcome measure was the rates of prostate-specific antigen declines ≧30 and ≧50%, respectively, with docetaxel. Secondary outcome measures included progression-free survival with docetaxel, and overall survival after initiation of abiraterone acetate and docetaxel. We performed correlation analysis between previous prostate-specific antigen response to abiraterone acetate and subsequent prostate-specific antigen response to docetaxel. RESULTS: We identified 15 patients had experienced disease progression with abiraterone acetate and subsequently were treated with docetaxel. Prostate-specific antigen declines ≧30 and ≧50% with docetaxel were observed in five patients (33%) and two patients (13%), respectively. The median progression-free survival with docetaxel was 3.7 months (95% confidence interval: 2.9-4.6). The median overall survival from initiation of docetaxel and abiraterone acetate were 14.4 months (95% confidence interval: 6.3-22.4), and 25.7 months (95% confidence interval: 20.1-30.7), respectively. No significant correlation was observed between these prostate-specific antigen responses (Pearson r = 0.206, P = 0.46). CONCLUSION: The efficacy of docetaxel in Japanese mCRPC patients that was resistant to abiraterone acetate was modest. The prostate-specific antigen response to previous abiraterone acetate could not predict the efficacy of subsequent docetaxel. Larger prospective trials are needed to validate these findings.
Authors: Aaron R Hansen; Ian F Tannock; Arnoud Templeton; Eric Chen; Andrew Evans; Jennifer Knox; Amy Prawira; Srikala S Sridhar; Susie Tan; Francisco Vera-Badillo; Lisa Wang; Bradly G Wouters; Anthony M Joshua Journal: Oncologist Date: 2019-04-05