Building on sipuleucel-t for immunologic treatment of castration-resistant prostate cancer

Abstract

Background: Sipuleucel-T is an autologous cellular immunotherapy approved by the US Food and Drug Administration for the treatment of asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer. Its mechanism of action is based on stimulation of the patient's own immune system to target prostate cancer. Peripheral blood mononuclear cells, including antigen-presenting cells and T cells, are obtained from patients via leukapheresis and treated ex vivo with PA2024, a fusion protein consisting of prostatic acid phosphatase/granulocyte-macrophage colony-stimulating factor antigen. Methods: Data relating to the potential pharmacodynamic biomarkers associated with sipuleucel-T activity are reviewed, as well as considerations for patient selection and for sequencing sipuleucel-T with other prostate cancer treatments. Possible directions for future development are also discussed, including treatment of less advanced prostate cancer populations, combination treatment, and immune modulation. Results: Data from three randomized, double-blind, placebo-controlled phase III clinical trials of sipuleucel-T in patients with metastatic castration-rresistant prostate cancer have shown improvement in overall survival vs control. Here, we review its developing role in prostate cancer therapy and future directions for development. Conclusions: There is potential to build on sipuleucel-T to further advance immunotherapy of prostate cancer.