Ospemifene for the treatment of dyspareunia in postmenopausal women.

Ospemifene is a third-generation selective estrogen receptor modulator (SERM), structurally closely related to toremifene. Clinical studies in postmenopausal women with vulvovaginal atrophy demonstrated that it produced significant improvements in the structure of the vagina and its pH, and significantly reduced dyspareunia, the main complaint of the women treated. Preclinical studies demonstrated that ospemifene, unlike tamoxifen, did not produce DNA adducts, suggesting that it has less carcinogenic potential than tamoxifen. Preclinical and clinical studies showed that ospemifene has an agonist action on bone and reduced the growth of all breast cancer models in animal studies, providing they expressed estrogen receptor-α. Ospemifene had minimal effects on the endometrium of postmenopausal women. Ospemifene 60 mg once a day was approved by the U.S. Food and Drug Administration in February 2013 for women with moderate to severe dyspareunia.