Abstract
Gonadotropin-releasing hormone (GnRH) receptor agonists are still the most commonly used androgen deprivation treatment (ADT) drugs for prostate cancer in clinical practice. Currently, the GnRH receptor antagonists used for endocrine therapy for prostate cancer primarily include degarelix and relugolix (TAK-385). The former is administered by subcutaneous injection, while the latter is an oral drug. Compared to GnRH agonists, GnRH antagonists reduce serum testosterone levels more rapidly without an initial testosterone surge or subsequent microsurges. This review focuses on the mechanism of action of GnRH antagonists and agonists, the developmental history of GnRH antagonists, and emerging data from clinical studies of the two antagonists used as endocrine therapy for prostate cancer.