TAK-683 is a potent full KISS1 receptor (KISS1R) agonist ( IC 50 =170 pM) with improved metabolic stability. TAK-683 is a nonapeptide metastin analog, exhibits agonistic activities to KISS1R with EC 50 values of 0.96 nM and 1.6 nM for human and rat, respectively. TAK-683 depletes GnRH in the hypothalamus and reduces plasma FSH , LH, and testosterone levels in vivo, it has the potential for the study of hormone-dependent prostate cancer.