A Randomized Phase 2 Trial of Immediate vs. Delayed Anti-Ctla4 Blockade Following Sipuleucel-T Treatment for Prostate Cancer Immunotherapy


Location(s): United States


The purpose of this study is to find out what effects taking ipilimumab, as an immediate or delayed treatment, following completion of sipuleucel-T (SipT) treatment, has on patients and their prostate cancer.

This is an open-label randomized multicenter Phase 2 clinical trial combining SipT with ipilimumab in patients with chemotherapy-naïve metastatic castration resistant prostate cancer (CRPC).

All patients will be treated with standard SipT (Q2wks x 3). Patients will be randomized to one of two arms:

Arm 1 (Immediate Treatment): Ipilimumab Q3wks x 4 started 1 day following the final dose of SipT (Day 0).

Arm 2 (Delayed Treatment): Ipilimumab Q3wks x 4 started 3 weeks following the final dose of SipT (Day 0).

Following this ipilimumab treatment, patients will then be followed monthly for 3 months and then quarterly until disease progression. The definition of unacceptable toxicity is grade 3 or higher treatment-related toxicities (NCI CTCAE v4) excluding irAEs. The study will assess for the immunogenicity and clinical activity of sequential sipuleucel-T treatment followed by ipilimumab. Patients who experience an initial clinical response to ipilimumab followed by subsequent disease progression will be offered reinduction treatment with ipilimumab.