Efficacy and safety of 3-month dosing regimen of degarelix in Japanese subjects with prostate cancer: A phase III study

Non-inferiority in the cumulative castration rate of the 3-month formulation of degarelix compared with the 3-month formulation of goserelin was evaluated in subjects with prostate cancer. A phase III, open-label, parallel-arm study was conducted. An initial dose of 240 mg of degarelix or 3.6 mg of goserelin was subcutaneously administered; after day 28, a maintenance dose of 480 mg of degarelix or 10.8 mg of goserelin was administered once every 84 days. Non-inferiority in castration rate and safety of degarelix to goserelin were evaluated. The primary endpoint was the cumulative castration rate from day 28 to day 364 and the non-inferiority margin was set to be 10%. A total of 234 subjects with prostate cancer were randomized to the degarelix group (n = 117) and the goserelin group (n = 117). The cumulative castration rate was 95.1% in the degarelix group and 100.0% in the goserelin group. Since there were no events in the goserelin group, an additional analysis was conducted using 95% CI of the difference in the proportion of subjects with castration. Analyses demonstrated the non-inferiority of the 3-month formulation of degarelix to goserelin. Degarelix showed more rapid decreases in testosterone, LH, FSH, and PSA levels compared with goserelin. The most common AEs in the degarelix group were injection site reactions. Non-inferiority of the 3-month formulation of degarelix to goserelin was demonstrated for testosterone suppression. The 3-month formulation of degarelix was also found to be tolerated as an androgen deprivation therapy for patients with prostate cancer. This article is protected by copyright. All rights reserved.

Cancer science. 2018 Apr 06 [Epub ahead of print]

Seiichiro Ozono, Taiji Tsukamoto, Seiji Naito, Shigeo Horie, Yasuo Ohashi, Hiroji Uemura, Yumiko Yokomizo, Satoshi Fukasawa, Hidehito Kusuoka, Rio Akazawa, Masako Saito, Hideyuki Akaza

Hamamatsu University School of Medicine., Sapporo Medical University., Harasanshin Hospital., Department of Urology, Juntendo University Graduate School of Medicine., Chuo University., Yokohama City University Medical Center., Yokohama City University., Chiba Cancer Center., Astellas Pharma Inc., Strategic Investigation on Comprehensive Cancer Network, The University of Tokyo.