This randomized phase II trial studies how well sipuleucel-T with or without radium Ra 223 dichloride works in treating patients with asymptomatic (no signs or symptoms of disease) or minimally symptomatic hormone-resistant prostate cancer that has spread to the bone (metastasis). Sipuleucel-T is made of immune system cells collected from patients with prostate cancer that are treated in the laboratory with a protein that is made by combining a protein found on prostate cancer cells with a growth factor. When the cells are injected back into the patient, they may stimulate T cells to kill prostate cancer cells. Radium 223 dichloride contains a radioactive substance called radium 223. Radium 223 collects in bone and gives off radiation that may kill cancer cells. It is not yet know whether sipuleucel-T with or without radium Ra 223 dichloride works is an effective treatment for patients with bone-metastasis hormone resistant prostate cancer.
Study sponsor and potential other locations can be found on ClinicalTrials.gov for NCT02463799.
PRIMARY OBJECTIVE:
I. To determine whether radium-223 (radium Ra 223 dichloride) in combination with sipuleucel-T enhances immune response to sipuleucel-T measured by peripheral PA2024-specific T-cell proliferation compared with sipuleucel-T alone in men asymptomatic or minimally symptomatic bone-metastatic castration resistant prostate cancer (CRPC).
SECONDARY OBJECTIVES:
I. To evaluate peripheral antigen-specific T-cell proliferation over time. (Immune Objectives)
II. To evaluate peripheral antigen specific T-cell activation to sipuleucel-T over time. (Immune Objectives)
III. To evaluate antigen specific antibody response to sipuleucel-T over time. (Immune Objectives)
IV. To evaluate the sipuleucel-T product immune parameters. (Immune Objectives)
V. To instigate safety of combined use of radium-223 and sipuleucel-T. (Clinical Objectives)
VI. To evaluate prostate specific antigen (PSA)50 response (at least a 50% decline in PSA). (Clinical Objectives)
VII. To evaluate time to radiographic or clinical progression. (Clinical Objectives)
OUTLINE: Patients are randomized to 1 of 2 treatment arms.
ARM I: Patients receive radium Ra 223 dichloride intravenously (IV) over 1 minute every 4 weeks for 6 doses in the absence of disease progression or unacceptable toxicity. Beginning week 6, patients also receive sipuleucel-T IV every 2 weeks for 3 doses in the absence of disease progression or unacceptable toxicity.
ARM II: Patients receive sipuleucel-T IV every 2 weeks for 3 doses in the absence of disease progression or unacceptable toxicity.
After completion of study treatment, patients are followed up at weeks 6, 10, 14, 26, 39, and 52 and then every 3 months for 1 year.
Lead OrganizationJohns Hopkins University/Sidney Kimmel Cancer Center
Principal InvestigatorEmmanuel S. Antonarakis