Duavive® is a combination product containing conjugated estrogens and bazedoxifene. This novel therapeutic combination is termed a tissue-selective estrogen complex (TSEC) and negates the need for opposing progestogen therapy. Duavive® is a new option for the treatment of moderate to severe vasomotor symptoms of menopause in women with a uterus.
Conjugated estrogens act as agonists at estrogen receptors, relieving symptoms associated with estrogen deficiency. Bazedoxifene is a selective estrogen receptor modulator (SERM) with agonist activity in bone and antagonist activity in breast and endometrial tissue. A recent study demonstrated a 30.4% relative risk reduction of new vertebral fractures in women with osteoporosis who were treated with bazedoxifene 20mg compared to placebo. Although the effect of Duavive® on the risk of breast cancer is unknown, the SMART studies show treatment is associated with a small, but significant, decrease in breast density. These trials also suggest a neutral effect on the endometrium. Rates of endometrial hyperplasia were <1% and, although one study showed an increase in endometrial thickness, no cases of endometrial carcinoma were reported.
Adverse effects occurred at a similar rate in the experimental and placebo groups, including no significant difference in the risk of ischaemic stroke, venous thromboembolism, and coronary heart disease. However, Duavive® is contraindicated in patients with thrombophilic disorders and an active or past history of thromboembolic disease. The most common adverse effects leading to discontinuation of therapy were abdominal pain and nausea.
- Duavive® (conjugated estrogens/bazedoxifene) Australian approved product information. West Ryde: Pfizer Australia. Approved December 2016.
- Palacios S, Silverman SL, De Villers TJ, Levine AB, Goemaere S, Brown JP, et al. A 7-Year randomized, placebo-controlled trial assessing the long-term efficacy and safety of bazedoxifene in postmenopausal women with osteoporosis. Menopause 2015; 22(8): 806-13.
- Pazhekattu R, Lau AN, Adachi JD. The tissue-selective estrogen complex: a review of current evidence. Rheumatol Ther. 2015; 2(1): 47-58.