New Agents for the Management of Castration-Resistant Prostate Cancer

Abstract

To review the activity of 3 new agents approved for the management of advanced castration-resistant prostate cancer (CRPC): sipuleucel-T, cabazitaxel, and abiraterone acetate. Literature was accessed through MEDLINE (1977-June 2012) and abstracts from the American Society of Clinical Oncology (2000-2012) using the terms castration-resistant and hormone-refractory prostate cancer, sipuleucel-T, cabazitaxel, abiraterone, Provenge, Jevtana, and Zytiga. Reference citations from publications identified were also reviewed. Articles identified from the data sources in English on human subjects were evaluated. Options for patients with CRPC have been limited, with little to offer those who failed or could not tolerate docetaxel-based therapy. Three new drugs, with very different mechanisms of action, have changed that and will undoubtedly change the treatment paradigm for these patients. Each 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 prior to 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 during or after docetaxel-based therapy. Abiraterone acetate, a hormonal therapy, improved median overall survival by 3.9 months and reduced the risk of death by 35% in patients with relapse during or after docetaxel-based therapy. The advent of new agents for the management of advanced CRPC has increased the choices for patients whose options were limited. Additional experience will determine the optimal sequencing of these agents, their roles in combination therapy, and their activity in patients with earlier disease.