Vivelle (estradiol transdermal system)

Vivelle provides estrogen replacement therapy by releasing estradiol through a controlled release patch. Estradiol is an estrogenic hormone secreted by the human ovary. Estrogen levels decrease after menopause, which may in turn increase the risk of osteoporosis. Vivelle works to counteract this loss through the continual release of estradiol. The hormone is contained in the adhesive of the patch, and the system is designed to release estradiol upon application to the skin.

In two controlled clinical trials of 356 subjects, two dose levels of Vivelle were tested. The 0.075 and 0.1 mg doses were superior to a placebo in relieving vasomotor symptoms at week four, and maintained efficacy through weeks eight and 12 of treatment. An additional 12-week placebo-controlled study in 255 patients was performed to test the lowest dose of 0.0375 mg. The 0.0375 mg dose was also superior to a placebo in reducing both the frequency and severity of vasomotor symptoms.

The Vivelle system's possible benefits in the prevention of postmenopausal osteoporosis have also been examined. A 2-year double-blind, randomized, placebo-controlled parallel group study was conducted with a total of 261 individuals. The enrolled group consisted of hysterectomized (161) and non-hysterectomized (100), surgically or naturally menopausal women (within 5 years of menopause), with no evidence of osteoporosis. There was an increase in bone mineral density (BMD) of the AP lumbar spine in all Vivelle groups, compared to a decrease in AP lumbar spine BMD observed in placebo patients. All Vivelle doses were significantly superior to a placebo at all time points with the exception of Vivelle 0.05 mg/day at 6 months. The highest dose of Vivelle was superior to the three lower doses. (from FDA Label)

Adverse reactions associated with Vivelle include (but are not limited to) the following:

• Headache
• Skin irritation at the application site
• Nausea
• Breast tenderness or enlargement
• Back pain
• Vaginal spotting or bleeding

Additionally, estrogens should not be used by individuals with any of the following conditions:

• Known or suspected pregnancy
• Undiagnosed abnormal genital bleeding
• Known or suspected breast cancer

Vivelle provides systemic estrogen replacement therapy through the release of estradiol. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level. The primary source of estrogen in normally cycling adult women is the ovarian follicle. After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone by peripheral tissues. Thus, estrone and the sulfate conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women.

Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and follicle stimulating hormone (FSH), through a negative feedback mechanism and estrogen therapy acts to reduce the elevated levels of these hormones seen in postmenopausal women. (from FDA Label)

For more information on osteoporosis, please visit the web site of The Endocrine Society. This site provides fact sheets for patients on a variety of topics.