Relugolix (TAK-385) is an orally active nonpeptide gonadotropin-releasing hormone (GnRH) that binds to human GnRH receptors with subnanomolar affinity. Relugolix was demonstrated to act as a classic competitive antagonist of GnRH binding, but the exact molecular mechanism of that antagonism remains unknown. This drug is being developed as a treatment for various sex hormone related disorders. Clinical trials have been conducted to study safety and efficacy of relugolix as a treatment in endometriosis, uterine fibroids (noncancerous growths of the uterus), and prostate cancer. Two phase III trials evaluating the efficacy of Relugolix in patients with uterine fibroids were completed in 2019. No serious adverse events were reported.