Survival benefit in prostate cancer with abiraterone acetate17 Mar 2016
Data from a post-hoc analysis of the Phase 3 COU-AA-302 trial has showed that abiraterone acetate (marketed as Zytiga) plus prednisone provided an 11.8 months overall survival (OS) benefit (53.6 months vs 41.8 months), compared to an active control of placebo plus prednisone, in men with early and less aggressive chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC).
Data from the post-hoc analysis demonstrated an increase in the overall survival benefit previously shown (4.4 months) in the final analysis of the COU-AA-302 trial.
Both groups experienced overall survival benefit
The post-hoc analysis divided patients into two groups to identify which group experienced a greater treatment benefit. The patients in Group 1 were in an earlier, less advanced and less symptomatic stage of the disease. Those in Group 2 were in a later, more advanced and more symptomatic stage of the disease.
The analysis revealed that patients in both groups experienced an overall survival benefit when treated with abiraterone acetate plus prednisone, compared to placebo plus prednisone.
“Post-hoc analyses such as this are very important in helping us to identify the patients who could benefit most from therapies such as novel hormone agents, and at what stage of a patient’s disease they could be most effective”, said Professor Kurt Miller, Department of Urology, Charité Berlin, Berlin, Germany.
“As men with prostate cancer are living longer, quality of life is an increasingly important factor for them and their families. It is therefore encouraging to see that when used earlier, patients can stay on abiraterone acetate for longer and delay the need for additional, more invasive treatments”, he continued.
Additional effects of the treatment
In addition to overall survival benefit, the post-hoc analysis data also revealed that both groups showed improvement in disease progression, cancer-related pain and treatment duration when treated with abiraterone acetate plus prednisone, compared to placebo plus prednisone.
- Time to chemotherapy use was increased by 12.7 months in Group 1 and 8.8 months in Group 2
- There was an improvement in median time to opiate use for cancer-related pain in both groups
- Median time on treatment increased in both groups