Astellas Pharma Inc. announced that results from the pivotal Phase 3 PROSPER trial, which evaluated enzalutamide plus androgen deprivation therapy (ADT) versus placebo plus ADT in patients with non-metastatic castration-resistant prostate cancer (CRPC), were published in the New England Journal of Medicine. The paper, ‘Enzalutamide in Men with Nonmetastatic, Castration-Resistant Prostate Cancer’, appears in the 28th June print edition of the Journal.
In the study, enzalutamide plus ADT significantly reduced the risk of developing metastases or death compared to ADT alone: 23% of patients in the enzalutamide and ADT arm had metastasis or had died, vs 49% in the ADT alone arm. The primary endpoint of median metastasis-free survival (MFS) was 36.6 months for men who received the treatment compared to 14.7 months with ADT alone.
Based on the results of the PROSPER study, Astellas submitted a Type II Variation to the European Medicines Agency (EMA) in January 2018 to extend the overall indication for enzalutamide to include patients with non-metastatic CRPC.
The treatment was first approved by the European Commission in June 2013 for the treatment of adult men with metastatic CRPC who are asymptomatic or mildly symptomatic after failure of androgen deprivation therapy. This is not currently licensed in the European Union for treatment of men with non-metastatic CRPC.