Secondary hormonal therapy for prostate cancer: what lies on the horizon?

Androgen deprivation therapy with medical or surgical castration is generally the first-line treatment against advanced prostate cancer. Almost invariably, metastatic prostate cancer overcomes testosterone depletion and grows, despite castrate levels of testosterone. Despite advances in cytotoxic chemotherapy, secondary hormonal therapies are often used after the development of castrate-resistant prostate cancer. Secondary hormonal therapies either lower the androgen levels further or directly antagonize the androgen receptor in prostate cancer cells. We discuss novel secondary hormonal agents that are under development, which work by either inhibiting androgen synthesis or directly targeting the androgen receptor.