A Randomized, Open-Label, Phase 2 Trial Examining the Sequencing of Sipuleucel-T and Androgen Deprivation Therapy in Men With Non-metastatic Prostate Cancer and a Rising Serum Prostate Specific Antigen After Primary Therapy
A Randomized, Open-Label, Phase 2 Trial Examining the Sequencing of Sipuleucel-T and Androgen Deprivation Therapy in Men With Non-metastatic Prostate Cancer and a Rising Serum Prostate Specific Antigen After Primary Therapy
The main purpose of this study was to determine whether ADT started before or after sipuleucel-T led to a better immune system response. This study also evaluated the safety of sipuleucel-T and ADT treatment, immune system responses over time, the characteristics of sipuleucel-T, and changes in prostate specific antigen (PSA) values over time.
Multicenter, randomized, open-label study, with subjects allocated (1:1) to 1 of 2 study arms, using a stratified randomization based on:
• Prostate-specific antigen doubling time (PSADT): ≤ 3 months or > 3 months and ≤ 12 months. • Primary therapy: radical prostatectomy (RP) or radiation, including brachytherapy, (XRT) or RP + XRT.
Arm 1: Subjects received one infusion of sipuleucel-T every two weeks for a total of three infusions. Two weeks after the third sipuleucel-T infusion, subjects started ADT with 45 mg leuprolide acetate depot injection (Eligard® 45 mg). An additional leuprolide acetate injection was administered at 6 months after the first injection for a total of 2 injections and 12 months of ADT.
Arm 2: Subjects started ADT with 45 mg leuprolide acetate depot injection (Eligard® 45 mg) 12 weeks before infusion 1 of sipuleucel-T. An additional leuprolide acetate injection was administered at 6 months after the first injection for a total of 2 injections and 12 months of ADT. Twelve weeks after the initial leuprolide 45 mg depot injection, subjects began one infusion of sipuleucel-T every two weeks for a total of three infusions.
Cellular and humoral immune responses were assessed for Arm 2 subjects at 12, 8, and 4 weeks pre infusion 1, and in all subjects (both arms) at pre-leukapheresis 1, 2, and 3, and post-infusion 1, 2 and 3, and at the following time points after the third infusion: Weeks 2, 6, and 12 and Months 6, 9, 12, 15, 18, 21, and 24.
Safety assessments included adverse event (AE) monitoring, laboratory tests (complete blood count (CBC) and serum chemistry), vital signs, Eastern Cooperative Oncology Group (ECOG) performance status, physical examination, as well PSA and testosterone monitoring. The study was complete at the 27-Month visit for Arm 1 and the 24-Month visit for Arm 2.
Inclusion Criteria:
Exclusion Criteria:
Requires systemic ongoing immunosuppressive therapy
History of allergic reactions attributed to compounds of similar chemical or biologic composition to sipuleucel-T or GM-CSF
Prior sipuleucel-T therapy
Prior ADT therapy ≤ 6 months prior to registration or ≥ 6 months duration in total
If subject has a history of any other stage III/IV malignancy, the subject must be disease free and off any malignancy-related treatment for at least 10 years. If the subject has a history of any stage I-II malignancy, the subject must be disease free and off any malignancy-related treatment for at least 5 years.
Prior experimental immunotherapy or on an experimental clinical trial within 1 year
Received denosumab or XRT ≤ 6 months prior to registration
Received chemotherapy or GM-CSF ≤ 90 days prior to registration
Received any of the following medications or interventions ≤ 28 days prior to registration
Active infection within 1 week of registration
Likely to receive XRT or surgery for prostate cancer during the study period
Any medical intervention, any other condition, or any circumstances that could compromise the study.