Overview
11 DESCRIPTION OSPHENA is an estrogen agonist/antagonist. OSPHENA is not a hormone. The chemical structure of ospemifene is shown in Figure 1. Figure 1: Chemical Structure The chemical designation is Z-2-[4-(4-chloro-1,2-diphenylbut-1-enyl)phenoxy]ethanol, and has the empirical formula C 24 H 23 ClO 2 , which corresponds to a molecular weight of 378.9.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action OSPHENA is an estrogen receptor 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). 12.2 Pharmacodynamics Generally, a serum estrogen concentration does not predict an individual woman’s therapeutic response to OSPHENA nor her risk for adverse outcomes. 12.3 Pharmacokinetics Absorption Following a single oral administration of OSPHENA 60 mg tablet in postmenopausal women under fasted condition, peak median serum concentration was reached at approximately 2 hours (range: 1 to 8 hours) post-dose (see Figure 2 ).
Indications
- 1 INDICATIONS AND USAGE OSPHENA is indicated for: OSPHENA is an estrogen agonist/antagonist indicated for: The treatment of moderate to severe dyspareunia, a symptom of vulvar and vaginal atrophy, due to menopause. ( 1.1 ) The treatment of moderate to severe vaginal dryness, a symptom of vulvar and vaginal atrophy, due to menopause. ( 1.2 ) 1.1 The Treatment of Moderate to Severe Dyspareunia, a Symptom of Vulvar and Vaginal Atrophy, due to Menopause. 1.2 The Treatment of Moderate to Severe Vaginal Dryness, a Symptom of Vulvar and Vaginal Atrophy, due to Menopause.
Common Doses
- 60 mg
Dosage
2 DOSAGE AND ADMINISTRATION OSPHENA is an estrogen agonist/antagonist which has agonistic effects on the endometrium [see Warnings and Precautions (5.2) ]. Use OSPHENA for the shortest duration consistent with treatment goals and risks for the individual woman. Reevaluate postmenopausal women periodically as clinically appropriate to determine if treatment is still necessary. One tablet taken orally once daily with food. ( 2.1 , 2.2 ) 2.1 Treatment of Moderate to Severe Dyspareunia, a Symptom of Vulvar and Vaginal Atrophy, Due to Menopause One 60 mg tablet taken orally with food once daily. 2.
Black Box Warning
WARNING: ENDOMETRIAL CANCER and CARDIOVASCULAR DISORDERS WARNING: ENDOMETRIAL CANCER and CARDIOVASCULAR DISORDERS See full prescribing information for complete boxed warning. OSPHENA is an estrogen agonist/antagonist with tissue selective effects. In the endometrium, OSPHENA has estrogen agonistic effects. There is an increased risk of endometrial cancer in a woman with a uterus who uses unopposed estrogens. Perform adequate diagnostic measures, including directed and random endometrial sampling when indicated, to rule out malignancy in postmenopausal women with undiagnosed persistent or...
Contraindications
- 4 CONTRAINDICATIONS OSPHENA is contraindicated in women with any of the following conditions: Undiagnosed abnormal genital bleeding. Estrogen-dependent neoplasia. Active DVT, PE, or a history of these conditions. Active arterial thromboembolic disease (for example, stroke and MI), or a history of these conditions. Hypersensitivity (for example, angioedema, urticaria, rash, pruritus) to OSPHENA or any ingredients. OSPHENA is contraindicated in women who are or may become pregnant. OSPHENA may cause fetal harm when administered to a pregnant woman.
Side Effects
- 6 ADVERSE REACTIONS The following serious adverse reactions are discussed elsewhere in the labeling: Cardiovascular Disorders [see Boxed Warning , Warnings and Precautions (5.1) ] Malignant Neoplasms [see Boxed Warning , Warnings and Precautions (5.2) ] The most common adverse reactions (≥1 percent) with OSPHENA are: hot flush, vaginal discharge, muscle spasms, headache, hyperhidrosis, vaginal hemorrhage, night sweats. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Duchesnay Inc. at 1-855-OSPHENA (1-855-677-4362) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.
Interactions
- 7 DRUG INTERACTIONS OSPHENA is primarily metabolized by CYP3A4 and CYP2C9. CYP2C19 and other pathways contribute to the metabolism of ospemifene. Do not use estrogens or estrogen agonist/antagonist concomitantly with OSPHENA. ( 7.1 , 12.3 ) Do not use fluconazole concomitantly with OSPHENA. Fluconazole increases serum concentrations of OSPHENA. ( 7.2 , 12.3 ) Do not use rifampin concomitantly with OSPHENA. Rifampin decreases serum concentration of OSPHENA. ( 7.2 , 12.3 ) 7.