The PROVENGE Phase 3 IMPACT Trial Design

The pivotal Phase 3 IMPACT trial was a randomized, double-blind, multicenter, controlled study in 512 men with asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer (CRPC).1

Primary endpoint: Overall survival

Secondary endpoint: Time to objective disease progression

The IMPACT Trial and PSA Levels

The main goal of the Phase 3 IMPACT trial was not to lower PSA levels—it was to extend survival.

Trial Design1

Phase Three IMPACT Trial (Immunotherapy for Prostate Adenocarcinoma Treatment) Trial

*Eligible patients were hormone refractory and had metastatic disease in the soft tissue and/or bone with evidence of progression; 18% had received prior chemotherapy (including docetaxel).
Control was nonactivated, autologous, peripheral blood mononuclear cells.
Progression=radiographic evidence of disease progression.
§Autologous, peripheral blood mononuclear cells that were cryopreserved at the time of control generation and subsequently activated.

  • 64% of patients in the control group, following progression, crossed over to a
    nonrandomized, open-label protocol to receive an investigational autologous
    immunotherapy made from cryopreserved cells1
  • Treatment in the open-label protocol was at the physician’s discretion

Phase 3 IMPACT Trial Results

Learn more about survival benefit with PROVENGE therapy.


  1. Kantoff PW, Higano CS, Shore ND, et al; for the IMPACT Study Investigators.
    Sipuleucel-T immunotherapy for castrate-resistant prostate cancer. N Engl J Med.