Ospemifene-d4 is intended for use as an internal standard for the quantification of ospemifene by GC- or LC-MS. Ospemifene is a non-hormonal selective estrogen receptor modulator (SERM).1 It binds to estrogen receptor α (ERα) and ERβ (Kis = 380 and 410 nM, respectively). It increases vaginal weight and vaginal epithelial height (ED50s = 0.48 and 0.39 mg/kg per day, respectively) in an ovariectomized rat model of menopause. Ospemifene also increases progesterone receptor protein expression in vaginal epithelium and stroma and inhibits estrogen response element-mediated transactivation induced by 17β-estradiol in a reporter assay using MCF-7 cells. Formulations containing ospemifene have been used in the treatment of vulvar and vaginal atrophy-induced dyspareunia.
1.Unkila, M., Kari, S., Yatkin, E., et al.Vaginal effects of ospemifene in the ovariectomized rat preclinical model of menopauseJ. Steroid Biochem. Mol. Biol.138107-115(2013)