Pfizer and Astellas have announced positive top-line results from the Phase III EMBARK trial evaluating XTANDI (enzalutamide) in men with non-metastatic hormone-sensitive prostate cancer (nmHSPC) with high-risk biochemical recurrence (BCR).
Patients enrolled in the trial were randomised to one of three study arms: XTANDI plus leuprolide, placebo plus leuprolide, or XTANDI monotherapy.
The study met its primary endpoint with a statistically significant and clinically meaningful improvement in metastasis-free survival (MFS) for patients treated with XTANDI plus leuprolide versus placebo plus leuprolide.
At the time of the analysis, a positive trend in the key secondary endpoint of overall survival (OS) was also observed, but these data were not yet mature. Patients in the trial will be followed for a subsequent final OS analysis.
The study also met a key secondary endpoint with a statistically significant and clinically meaningful improvement in MFS for patients treated with XTANDI monotherapy versus placebo plus leuprolide.
Additional key secondary endpoints reached statistical significance, including time to PSA progression and time to first use of new antineoplastic therapy.
“While current treatment options for localised prostate cancer are intended to be curative, some men remain at higher risk for biochemical recurrence following primary treatment, which may result in metastases,” said Ahsan Arozullah, Senior Vice President and Head of Development Therapeutic Areas, Astellas.
“The EMBARK trial is the first study to demonstrate a statistically significant improvement in MFS using the combination of XTANDI plus leuprolide in men with this stage of disease.”
These data will be used to support a potential regulatory submission for XTANDI in this indication.