PR.17 (ENZAMET) trial: Enzalutamide in prostate cancer that has spread but has not yet been treated with hormones

Monday, October 19, 2015

Treatment for newly-diagnosed metastatic prostate cancer involves androgen deprivation therapy (ADT). ADT aims to stop the testicles from producing androgen and to block the effects of androgens produced in other parts of the body. Enzalutamide (formerly known as MDV3100) is a new oral drug that has shown to be more potent and effective in blocking androgen receptor interactions compared to other anti-androgen drugs.  

Recent studies show promising results with the use of enzalutamide in patients who have metastatic prostate cancer that has progressed while on ADT, whether it is given before or after chemotherapy. Enzalutamide, in both settings, as compared with placebo, significantly extended survival with delays in disease progression, improved patient-reported quality of life and had a favourable adverse event profile.

The PR.17 (ENZAMET) trial is based on the hypothesis that earlier use of enzalutamide will prevent or delay disease progression and will prolong survival. PR.17 is an investigator-initiated trial that will involve about 1100 men with prostate cancer that has spread, but has not yet been treated with hormones. Astellas Scientific and Medical Affairs Inc. are providing enzalutamide.

PR.17 is accruing strongly with over 250 patients now enrolled. It is expected that recruitment will continue to accelerate with strong international support and multiple sites now open in Australia, Ireland, UK, Canada, New Zealand and the United States. Nine Canadian sites have been activated since May 2015 and 16 patients were randomized by the end of September.

If you belong to a Canadian centre interested in participating in PR.17:

Several Canadian sites are currently working on their local activation processes or are evaluating the feasibility of opening this trial. Please note that Canadian Cancer Trials Group centre participation is limited to 25. Given these considerations, we ask that every effort be made to evaluate the ability of your centre to make a meaningful contribution to this study. If your site is working or interested in activating this trial, we could guide your site with the required documentation. Please urgently contact Alexander Montenegro, PR.17 Study Coordinator, at 613-533-6430 or