Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
OSPHENA vs EVISTA
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Selective estrogen receptor modulator (SERM) that acts as an estrogen agonist on bone and lipid metabolism, and as an estrogen antagonist on breast and uterine tissue. It mimics estrogen's effects on bone by reducing bone resorption and increasing bone mineral density.
Selective estrogen receptor modulator (SERM) that binds to estrogen receptors, acting as an agonist in bone and antagonist in breast and uterine tissues.
Treatment of osteoporosis in postmenopausal women at high risk of fracture,Reduction in risk of invasive breast cancer in postmenopausal women with osteoporosis,Reduction in risk of invasive breast cancer in postmenopausal women at high risk for invasive breast cancer
Treatment and prevention of osteoporosis in postmenopausal women,Reduction in risk of invasive breast cancer in postmenopausal women with osteoporosis,Reduction in risk of invasive breast cancer in postmenopausal women at high risk for breast cancer
60 mg orally once daily with food.
60 mg orally once daily.
The terminal elimination half-life of ospemifene is approximately 26 hours (range 22-39 hours), supporting once-daily dosing.
Terminal elimination half-life is approximately 32.5 hours (range 27-39 hours) for raloxifene and its glucuronide conjugates; clinically relevant for once-daily dosing.
Extensively metabolized in the liver via glucuronidation (UGT1A8, UGT1A10, UGT2B7) and to a lesser extent by cytochrome P450 (CYP3A4, CYP2C19). Undergoes enterohepatic recycling. Half-life is approximately 5.7 days.
Extensively metabolized in the liver via glucuronidation (UGT1A1, UGT1A8, UGT1A9) and CYP3A4-mediated oxidation.
Following oral administration, 50% of a radiolabeled dose is excreted in urine and 35% in feces within 168 hours, primarily as glucuronide conjugates; <1% is excreted unchanged.
Raloxifene undergoes extensive glucuronidation; <0.1% excreted unchanged in urine. Approximately 95% is excreted in feces over 5 days (primarily as glucuronide conjugates). Renal elimination of unchanged drug is negligible (<0.1%).
Ospemifene is >99% bound to plasma proteins, primarily albumin.
>95% bound to plasma proteins, primarily albumin and α1-acid glycoprotein.
The apparent volume of distribution (Vd/F) is approximately 2.4 L/kg, indicating extensive tissue distribution.
Apparent Vd/F is approximately 1000-1500 L (not weight-based; extensive tissue distribution).
Absolute bioavailability is approximately 30% after oral administration due to first-pass metabolism.
Absolute oral bioavailability is approximately 2% due to extensive first-pass glucuronidation; systemic exposure is dose-proportional.
No dose adjustment required for mild to moderate renal impairment; not studied in severe renal impairment (Cr Cl <30 m L/min).
No dose adjustment required for mild to moderate renal impairment (Cr Cl ≥30 m L/min). Not recommended in severe renal impairment (Cr Cl <30 m L/min) due to lack of data.
Child-Pugh A: no adjustment; Child-Pugh B: not recommended; Child-Pugh C: contraindicated.
Contraindicated in patients with Child-Pugh Class B or C hepatic impairment. No specific dose adjustment recommended for Child-Pugh Class A, but use with caution.
Safety and efficacy not established; no specific dosing guidelines.
Safety and efficacy not established in pediatric patients; no recommended dose.
No specific dose adjustment; monitor for dysphagia and esophageal adverse effects.
No specific dose adjustment required; use standard adult dosing. Consider increased risk of venous thromboembolism and stroke in elderly women.
Increased risk of venous thromboembolic events (including deep vein thrombosis and pulmonary embolism) and death due to stroke. Use is contraindicated in women with active or past history of venous thromboembolism.
Increased risk of venous thromboembolism (VTE) and death from stroke. Not for use in women with active or history of VTE, including deep vein thrombosis, pulmonary embolism, and retinal vein thrombosis. Not for use in women with atrial fibrillation or other conditions that increase risk of stroke.
Increased risk of venous thromboembolic events and stroke; consider risk-benefit in women at risk for these events. May cause hot flashes and leg cramps. Use with caution in patients with hepatic impairment or history of cholestasis. Not recommended for use in premenopausal women. Discontinue if prolonged immobilization occurs. Monitor lipid profile; may cause small reductions in HDL cholesterol.
Risk of VTE; discontinue if VTE occurs. Risk of stroke; discontinue if stroke occurs or for prolonged immobilization. May increase risk of endometrial cancer; monitor for abnormal bleeding. Not for premenopausal women. Use with caution in patients with hepatic impairment or cholestasis. May increase triglycerides; monitor in patients with history of hypertriglyceridemia.
Active or past history of venous thromboembolism (DVT, PE, retinal vein thrombosis), pregnancy (can cause fetal harm), women who are or may become pregnant, nursing mothers, patients with hypersensitivity to raloxifene or any component of the formulation.
Active or history of VTE, pregnancy, women who may become pregnant, lactation, hypersensitivity to raloxifene, or any component of the formulation.
No specific food interactions; take with food to minimize gastrointestinal side effects.
Avoid grapefruit and grapefruit juice as they may increase raloxifene levels. No other significant food interactions.
Ospemifene is contraindicated in pregnancy. Based on its mechanism as a selective estrogen receptor modulator (SERM) and animal studies showing embryotoxicity and teratogenicity, there is potential for fetal harm. First trimester exposure may increase risk of congenital anomalies; second/third trimester exposure may cause urogenital tract abnormalities and endocrine disruption.
Pregnancy Category X. Raloxifene is contraindicated in pregnancy. In animal studies, raloxifene caused fetal abnormalities including skeletal malformations and cardiovascular defects. Human data are unavailable due to contraindication; use in pregnancy may cause fetal harm.
No data on human milk excretion. Ospemifene may suppress lactation due to estrogenic effects. M/P ratio unknown. Avoid breastfeeding during treatment and for at least 2 weeks after last dose.
Raloxifene is excreted in rat milk; no human data available. The M/P ratio is unknown. Due to potential adverse effects on the infant, breastfeeding is not recommended during therapy.
No dose adjustments studied; contraindicated in pregnancy. Pharmacokinetic changes (e.g., increased volume of distribution, altered clearance) may occur but no data to guide dosing.
No dosing adjustments are applicable as raloxifene is contraindicated in pregnancy. Pharmacokinetic changes in pregnancy do not inform dose modifications due to the contraindication.
Ospemifene is a selective estrogen receptor modulator (SERM) indicated for moderate to severe dyspareunia due to vulvar and vaginal atrophy in postmenopausal women. Avoid in women with estrogen-dependent neoplasia, unexplained genital bleeding, or prior thromboembolic events. Monitor for endometrial hyperplasia because uterine stimulation can occur. Not for use in premenopausal women.
Monitor for venous thromboembolism; avoid in patients with active or history of VTE. May increase risk of stroke in postmenopausal women with coronary heart disease. No significant effect on breast cancer incidence. Administer with caution in hepatic impairment. Discontinue prior to prolonged immobilization or surgery.
Take daily with food to reduce nausea.,Do not take if you have a history of blood clots, breast cancer, or uterine cancer.,Report any unusual vaginal bleeding, breast pain, or leg swelling immediately.,May cause hot flashes, vaginal discharge, or muscle spasms.,Use proper lubricants during intercourse; this medicine does not protect against STIs.,Continue regular pelvic exams and mammograms as recommended.
Take once daily with or without food.,Report any signs of blood clots (leg pain/swelling, sudden chest pain, shortness of breath).,May cause hot flashes, leg cramps, or flu-like symptoms.,Avoid pregnancy; not indicated for premenopausal women.,Requires adequate calcium and vitamin D intake.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about OSPHENA vs EVISTA, answered by our medical review team.
OSPHENA is a Selective Estrogen Receptor Modulator (SERM) that works by Selective estrogen receptor modulator (SERM) that acts as an estrogen agonist on bone and lipid metabolism, and as an estrogen antagonist on breast and uterine tissue. It mimics estrogen's effects on bone by reducing bone resorption and increasing bone mineral density.. EVISTA is a Selective Estrogen Receptor Modulator that works by Selective estrogen receptor modulator (SERM) that binds to estrogen receptors, acting as an agonist in bone and antagonist in breast and uterine tissues.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between OSPHENA and EVISTA depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of OSPHENA is: 60 mg orally once daily with food.. The standard adult dose of EVISTA is: 60 mg orally once daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between OSPHENA and EVISTA in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. OSPHENA is classified as Category C. Ospemifene is contraindicated in pregnancy. Based on its mechanism as a selective estrogen receptor modulator (SERM) and animal studies showing embryotoxicity and teratogenicity, t. EVISTA is classified as Category C. Pregnancy Category X. Raloxifene is contraindicated in pregnancy. In animal studies, raloxifene caused fetal abnormalities including skeletal malformations and cardiovascular defec. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.