Osphena (ospemifene) is an estrogen agonist/antagonist with tissue selective effects. It binds to estrogen receptors, resulting in the activation of estrogenic pathways in some tissues and the blockade of estrogenic pathways in other tissues.
Osphena is specifically indicated for the treatment of moderate to severe dyspareunia, a symptom of vulvar and vaginal atrophy, due to menopause.
Osphena is supplied as a tablet for oral administration. The recommended dose is one 60 mg tablet with food once daily. Use of Osphena should be for the shortest duration consistent with treatment goals and risks. For postmenopausal woman with a uterus, the addition of a progestin should be considered to reduce the risk of endometrial cancer. A woman without a uterus does not need a progestin.
The FDA approval of Osphena was based on three placebo-controlled clinical trials (two 12-week efficacy trials and one 52-week long-term safety trial).
This 12-week, randomized, double-blind, placebo-controlled, parallel-group study enrolled 826 generally healthy postmenopausal women between 41 to 81 years of age with at least one moderate to severe vaginal symptom. Treatment groups included 30 mg or 60 mg Osphena or placebo. All women were assessed for improvement in the mean change from Baseline to Week 12 for the co-primary efficacy variables of: most bothersome symptom (MBS) of vulvar and vaginal atrophy (defined by each individual), percentage of vaginal superficial and vaginal parabasal cells on a vaginal smear, and vaginal pH.
This 12-week, randomized, double-blind, placebo-controlled, parallel-group study enrolled 919 generally healthy postmenopausal women between 41 to 79 years of age with moderate to severe vaginal dryness (dryness cohort) or moderate to severe dyspareunia (dyspareunia cohort). The subjects received 60 mg Osphena or placebo. Primary endpoints and study conduct were similar to those in Trial 1.
This 52-week, randomized, double-blind, placebo-controlled, long-term safety study enrolled 426 generally healthy postmenopausal women between 49 to 79 years of age with an intact uterus. Treatment groups included 60 mg Ospehna or placebo.
In the 1st and 2nd clinical trial, the modified intent-to-treat population of women treated with Osphena when compared to placebo, demonstrated a statistically significant improvement (least square mean change from Baseline to Week 12) in the moderate to severe MBS of dyspareunia (1st trial p=0.0012, 2nd trial p<0.0001). A statistically significant increase in the proportion of superficial cells and a corresponding statistically significant decrease in the proportion of parabasal cells on a vaginal smear was also demonstrated (p<0.0001 for both). The mean reduction in vaginal pH between baseline and Week 12 was also statistically significant (p<0.0001). In the long-term safety study daily doses of 60mg of Ophena were well-tolerated with most treatment-emergent adverse events being mild or moderate in severity.
Adverse events associated with the use of Osphena may include, but are not limited to, the following:
Osphena (ospemifene) is an estrogen agonist/antagonist with tissue selective effects. Its biological actions are mediated through binding to estrogen receptors. This binding results in activation of estrogenic pathways in some tissues (agonism) and blockade of estrogenic pathways in others (antagonism).
Portman DJ, Bachmann GA, Simon JA; and the Ospemifene Study Group Ospemifene, a novel selective estrogen receptor modulator for treating dyspareunia associated with postmenopausal vulvar and vaginal atrophy. Menopause 2013 Jan 28
Simon JA, Lin VH, Radovich C, Bachmann GA; The Ospemifene Study Group One-year long-term safety extension study of ospemifene for the treatment of vulvar and vaginal atrophy in postmenopausal women with a uterus. Menopause 2012 Nov 8
Bachmann GA, Komi JO; Ospemifene Study Group Ospemifene effectively treats vulvovaginal atrophy in postmenopausal women: results from a pivotal phase 3 study. Menopause 2010 May-Jun;17(3):480-6
For additional information regarding Osphena or dyspareunia, please visit the Osphena web page.