In the June 4, 2020, issue of The New England Journal of Medicine, Weill Cornell Medicine faculty reported on very promising results of a phase 3 clinical trial focused on overall survival in men with nonmetastatic, castration-resistant prostate cancer whose PSA levels doubled within 10 months. The study, led by Cora N. Sternberg, MD, a specialist in urologic cancer and Clinical Director of the Englander Institute for Precision Medicine at Weill Cornell, is the PROSPER study of enzalutamide – an androgen receptor inhibitor – in patients with nonmetastatic castration-resistant prostate cancer.
In 2018, the FDA approved enzalutamide in combination with androgen-deprivation therapy to treat nonmetastatic, castration-resistant prostate cancer based on results of the PROSPER phase 3 trial, which showed a significantly lower risk of metastasis or death without radiographic progression than with androgen-deprivation therapy alone. And while this was clearly encouraging, data on overall survival was immature.
Analysis of overall survival in the current phase 3 trial, conducted at more than 250 sites in 32 countries around the world, demonstrated that treatment with enzalutamide was associated with a significant 27 percent lower risk of death than placebo in men than those only receiving androgen-deprivation therapy, despite the use of subsequent life-prolonging antineoplastic therapies (including enzalutamide) by patients in the placebo group. Additionally, the time to subsequent antineoplastic therapy, time to cytotoxic chemotherapy, and chemotherapy-free survival were also longer in the enzalutamide group than in the placebo group.
According to the authors, “These results add to the growing body of evidence that androgen-receptor inhibitors not only delay the time to metastasis but also improve overall survival among men with nonmetastatic, castration-resistant prostate cancer.”