Products
Bazedoxifene is commercially available in the form of film-coated tablets (Conbriza). It has been approved in many countries since 2010. In 2015, a fixed combination with conjugated estrogens was registered (Duavive). This article refers to monotherapy.
Structure and properties
Bazedoxifene (C30H34N2O3, Mr = 470.60 g/mol) is a nonsteroidal selective estrogen receptor modulator developed from raloxifene. Instead of the benzothiophene ring, bazedoxifene contains an indole ring. In the drug, it is present as bazedoxifene acetate. It is referred to as 3rd generation SERM by the manufacturer.
Effects
Bazedoxifene (ATC G03XC02) is a nonsteroidal SERM with estrogen agonistic and antagonistic properties. It exhibits agonistic and antiresorptive effects on bone tissue and lipid metabolism but has antagonistic effects on breast tissue and endometrium. Bazedoxifene may be somewhat more specific than raloxifene, especially at the uterus.
Indications
- For the treatment and prevention of postmenopausal osteoporosis in women at increased risk of fracture (Conbriza).
- For the treatment of symptoms of estrogen deficiency in postmenopausal women with confirmed menopause and preserved uterus (Duavive).
Dosage
According to the drug label. The usual dose is 20 mg once daily regardless of meals and time of day. Once-daily administration is possible due to the long half-life of 28 hours.
Contraindications
For complete precautions, see the drug label.
Interactions
Bazedoxifene is conjugated in the liver primarily to bazedoxifene-5-glucuronide. The major portion is excreted in the stool. The cytochrome P450 system is poorly involved in metabolism, so interactions at the level of the CYP enzyme system are considered unlikely.
Adverse effects
Very common adverse effects, as with other SERMs, include flushing, constipation, and calf cramps (muscle spasms). Hypersensitivity, drowsiness, nausea, urticaria, peripheral edema, transaminase elevation, serum triglyceride elevation, dry mouth, and dry vagina are common. Occasionally, venous thromboembolic events and, in very rare cases, retinal vein thrombosis occur.
