AUA 2017: Impact Of Abiraterone Acetate In The Post-docetaxel Setting On The Survival Of Metastatic Castration-resistant Prostate Cancer Patients: A Population-based Study In Quebec

Boston, MA ( Abiraterone was introduced in Quebec in 2012 for metastatic castration-resistant prostate cancer (mCRPC) in the post-docetaxel setting. This study described abiraterone utilization in the early post-approval period and its clinical effectiveness in Quebec, for both post-chemotherapy patients and patients unfit for chemotherapy.

This was a retrospective cohort study conducted using Quebec public healthcare administrative databases. The study population consisted of men 40 years and older with a diagnosis of mCRPC, who received a first treatment of abiraterone between 2012 and 2013. Treatment groups were defined as: 1) Abiraterone post chemotherapy and 2) Abiraterone “exception patient”, for chemotherapy-ineligible patients treated with abiraterone authorized by the “exception patient” measure category. The primary outcome was overall survival since abiraterone initiation.

The study cohort consisted of 303 mCRPC patients treated with abiraterone (abiraterone post-chemotherapy: 99 and abiraterone “exception patient”: 204). The median age was 75.0 for the abiraterone post-chemotherapy group and 80.0 for the abiraterone “exception patient” group. Overall 123 deaths occurred with an OS time of 18 months. The corresponding median survivals were 12 and 14 months, respectively (log-rank test p-value=0.815). Risk of death was similar in the abiraterone post-chemotherapy and abiraterone “exception patient” groups (hazard ratio (HR): 0.89; 95%CI 0.57-1.38).

To conclude, effectiveness of abiraterone in older patients who were chemotherapy ineligible was similar to that of patients with prior docetaxel exposure. Overall, this study’s “real-world” data demonstrated that the survival benefits of abiraterone are similar to that shown in the COU-AA-301 trial.

Presented by: Alice Dragomir, Montreal, Canada

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre

Twitter: @Goldberghanan

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA