LONDON CANCER NEW DRUGS GROUP RAPID REVIEW Abiraterone for the treatment of metastatic castration-resistant prostate cancer that has progressed on or after a docetaxel-based chemotherapy regimen

It is estimated that around 55-60% of men with prostate cancer will develop metastatic disease, most commonly involving bone. The initial treatment for metastatic disease is hormonal ablation, either with surgery (bilateral orchidectomy) or medically with gonadotrophin releasing hormone analogues such as goserelin, leuprorelin or triptorelin. A luteinising hormone-releasing hormone (LHRH) antagonist is also now available (degarelix) – this avoids the initial testosterone flare that is seen with the agonists. Although most patients will initially respond to this type of therapy, the disease usually progresses in the presence of castrate levels of testosterone after around 12-18 months and alternative treatment strategies are then required. The cancer may respond to additional hormonal strategies, but ultimately the cancer becomes unresponsive to further conventional hormonal manipulation.