ABSTRACT

Androgen deprivation therapy (ADT) is generally the initial treatment for males with metastatic prostate cancer. Standard approaches include bilateral orchiectomy or medical orchiectomy using a gonadotropin releasing hormone (GnRH) agonist either alone or in combination with an antiandrogen (complete androgen blockade). Despite initial response rates of 80 to 90 percent, nearly all males eventually develop progressive disease following ADT; this is referred to as castrate-resistant prostate cancer. Despite the fact that serum testosterone rates are at castration level, castration resistant prostate cancer (CRPC) is defined as rising serum prostate specific androgen values or progressive disease that is identified by imaging studies. Options for patients with CRPC are limited, and the options run even lower if docetaxel-based therapy is unsuccessful or not tolerated. Two new drugs, with very different mechanisms of action, have undoubtedly change treatment paradigms for these patients. Both of agent has demonstrated an impact on patient survival. Sipuleucel-T, the first immunotherapy approved for treatment of CRPC, improved median overall survival by 4.1 months and reduced the risk of death by 22% in a placebo-controlled trial of asymptomatic patients. Sipuleucel-T can be administered before docetaxel-based therapy. Cabazitaxel, a taxane chemotherapy agent, improved median overall survival by 2.4 months and reduced the risk of death by 30% in a Phase 3 trial of patients whose cancer progressed after docetaxel-based therapy.