Does Enzalutamide Affect Metastasis-Free Survival in Men With Aggressive Prostate Cancer?
Posted: Thursday, October 4, 2018
According to a study published in The New England Journal of Medicine, enzalutamide treatment in men with nonmetastatic, castration-resistant prostate cancer resulted in a 71% decrease in the risk of metastasis or death. Researchers sought to determine the drug’s effect on metastasis-free survival. Maha Hussein, MD, of Northwestern University, and colleagues also reported a “significant delay in the time to the first use of a subsequent antineoplastic therapy and in the time to [prostate-specific antigen] progression, with no difference in quality of life between the enzalutamide group and the placebo group.”
A total of 1,401 patients with nonmetastatic, castration-resistant prostate cancer participated in the study. Participants had a prostate-specific antigen (PSA) level doubling time no greater than 10 months. Participants were randomized 2:1 to receive enzalutamide (n = 933) or placebo (n = 468). All patients continued to receive androgen-deprivation therapy for the duration of the study.
In the enzalutamide group, the median metastasis-free survival was 36.6 months, versus 14.7 months in the placebo group (hazard ratio = 0.29). The enzalutamide group did not require the use of a subsequent antineoplastic therapy for 39.6 months, whereas the placebo group used such therapy at 17.7 months (hazard ratio = 0.21). The time to PSA progression was also longer for the enzalutamide group at 37.2 months versus 3.9 months for the placebo group (hazard ratio = 0.07). At the first assessment of overall survival, 11% of the patients treated with enzalutamide and 13% of patients receiving the placebo had died.
As for toxicity, 31% of patients taking enzalutamide reported adverse events grade 3 or higher, whereas 23% of the patients taking placebo reported the same. Fatigue was the only adverse event of any grade occurring in more than 20% of patients treated with enzalutamide.