Ospemifene (brand names Osphena and Senshio produced by Shionogi) is an oral medication indicated for the treatment of dyspareunia – pain during sexual intercourse – encountered by some women, more often in those who are post-menopausal.

In the US it is indicated for the treatment of moderate to severe dyspareunia, a symptom of vulvar and vaginal atrophy (VVA), due to menopause.

In the EU it is indicated for the treatment of moderate to severe symptomatic VVA in post-menopausal women who are not candidates for local vaginal oestrogen therapy.

[citation needed] Women with "undiagnosed abnormal genital bleeding; known or suspected estrogen-dependent neoplasia; active or history of deep vein thrombosis; pulmonary embolism; arterial thromboembolic disease; and are or may become pregnant" or "with known or suspected breast cancer or those with extreme hepatic impairment" should not take ospemifene.

The boxed warning of the medication indicates ospemifene may thicken the endometrium, which could lead to unusual bleeding and endometrial cancer.

Like estrogens, ospemifene also may increase the risk for cardiovascular events, including "stroke, coronary heart disease, venous thromboembolism," and others.

[citation needed] Ospemifene is "an estrogen agonist/antagonist that makes vaginal tissue thicker and less fragile resulting in a reduction in the amount of pain women experience with sexual intercourse.

[9] Hormos Medical Ltd., which is a part of QuatRx Pharmaceuticals, filed a patent on January 19, 2005, for a solid dosage form of ospemifene.

[12] Ospemifene (under the brand name Senshio) was subsequently approved by the European Commission for marketing in the EU in January 2015.

[10] The number of progesterone receptors was increased in the vaginal stroma and epithelium, which indicates that ospemifene has "estrogenic activity.

"[14] Ospemifene produced more changes in vaginal tissue and greater reduction in dyspareunia symptoms than placebo.

The other phase 3 trial was conducted in 605 women aged 40 to 80, who were diagnosed with VVA, and whose worst symptom was dyspareunia.