Abiraterone improves bone-related symptoms in patients with metastatic prostate cancer

This study evaluated the effect of abiraterone acetate plus prednisone on pain and skeletal-related symptoms in patients with metastatic castration-resistant prostate cancer (mCRPC) after docetaxel chemotherapy.

Prostate cancer growth is fueled by testosterone, the main male sex hormone. Treatment options include surgery or drugs to reduce the amount of testosterone produced by the body (hormone therapy). However, prostate cancer can become resistant to hormone therapy. This is called castration-resistant prostate cancer (CRPC). Often, CRPC can spread to distant organs or tissues such as bones, liver or lungs. This is called metastatic CRPC. Bone metastases can cause important pain and other skeletal-related events (such as breaking of the bones), which can significantly affect patients’ quality of life. Abiraterone acetate (Zytiga) is a hormone therapy drug that has been shown to improve survival in patients with mCRPC. Abiraterone is given together with a steroid drug called prednisone, which reduces side effects to treatment. The authors of this study evaluated whether abiraterone acetate plus prednisone has any effects on pain and bone-related symptoms in patients with mCRPC.

A total of 1195 patients with mCRPC were included in this research. All patients had previously received docetaxel-based chemotherapy. 797 patients were randomly assigned to receive abiraterone acetate plus prednisone and 398 to receive placebo (a substance with no medical effect used as control when testing new drugs) plus prednisone.

After approximately 20 months of follow up, 45% of patients who received abiraterone acetate and prednisone experienced pain relief compared to 28.8% patients treated with placebo and prednisone. Also, patients in the abiraterone acetate group experienced faster pain relief than those in the placebo group (5.6 months versus 13.7 months). Patients treated with abiraterone plus prednisone had a longer period until they experienced a skeletal-related event than those treated with prednisone plus placebo (25 months versus 20.3 months). 

In summary, the study showed that the use of abiraterone acetate plus prednisone was effective in reducing pain and skeletal-related events in patients with mCRPC.