Emerging treatment options for patients with castration-resistant prostate cancer

BACKGROUND Most prostate cancer-related deaths occur in patients with castration-resistant prostate cancer (CRPC). Recent preclinical and clinical studies have identified intracellular signaling pathways and changes in the tumor and bone microenvironment as potential key drivers of CRPC. This increased understanding of mechanisms associated with CRPC has driven the development of numerous new agents, many of which are poised to alter the current CRPC treatment landscape. METHODS A review of literature was conducted to identify ongoing and planned phase III studies of novel agents to treat CRPC. RESULTS Multiple studies were identified, including novel androgen biosynthesis inhibitors (abiraterone, TAK-700), androgen-receptor inhibitors (MDV3100), angiogenesis inhibitors (aflibercept, tasquinimod), endothelin antagonists (zibotentan, atrasentan), a Src tyrosine kinase inhibitor (dasatinib), a novel radiotherapy (radium-223), and new immunotherapies (ipilimumab and ProstVac). In addition, both sipuleucel-T (an immunotherapy) and cabazitaxel (third-generation taxane) and the RANK-L inhibitor, denosumab, have recently been approved by the US Food and Drug Administration. CONCLUSIONS Various combinations of these agents could theoretically be used to treat future patients with CRPC by targeting multiple signaling pathways as well as aspects of the tumor and bone microenvironments. Additional research will be needed to understand how to best use these agents and individualize care to optimize CRPC patient outcomes. Prostate 72:338–349, 2012. © 2011 Wiley Periodicals, Inc.