Wyeth Pharmaceuticals, a division of Wyeth, presented new data from two phase III studies, which showed that bazedoxifene/conjugated estrogens reduced the number and severity of hot flashes in symptomatic postmenopausal women by up to 80 per cent, when compared with placebo.

These data, presented at the North American Menopause Society Annual Meeting, also showed that bazedoxifene/conjugated estrogens improved symptoms of vulvar and vaginal atrophy. In addition, secondary data from both studies showed that when compared with placebo, bazedoxifene/conjugated estrogens reduced sleep disturbances and improved menopause-related quality of life.

"The pairing of bazedoxifene, a selective estrogen receptor modulator, or SERM, with conjugated estrogens may lead to a new class of menopausal therapy called tissue selective estrogen complex, or TSEC," says Ginger Constantine, M D, vice president, Women's Health Care and Bone Repair, Wyeth Pharmaceuticals. "TSECs pair the benefits of estrogens with SERMs to create a distinct clinical profile, which may provide relief of hot flashes and vaginal dryness as well as bone and uterine protection".

Wyeth has plans to submit its New Drug Application (NDA) to the US Food and Drug Administration for bazedoxifene/conjugated estrogens in the second quarter of 2008 subject to the further analysis and successful completion of product formulation, bioequivalence and clinical studies, and other remaining work necessary to finalize the NDA.

Results of a clinical trial titled "A phase III Study of the Efficacy and Safety of Bazedoxifene/Conjugated Estrogens for Treatment of Menopausal Vasomotor Symptoms," which evaluated 332 symptomatic postmenopausal women who, at baseline, experienced seven or more moderate to severe hot flashes per day or 50 or more hot flashes per week were presented. The study showed that, when compared with placebo, bazedoxifene/conjugated estrogens significantly reduced the number and severity of hot flashes. Furthermore, the incidences of breast pain and bleeding were less than five per cent and did not differ from placebo. The most commonly reported adverse events were headache and joint pain.

Data from another phase III study titled "Effects of the TSEC Bazedoxifene and Conjugated Estrogens on vulvar/vaginal atrophy and sexual function in postmenopausal women," which evaluated 601 postmenopausal women with moderate to severe vulvar and vaginal atrophy, also were presented. These data showed that bazedoxifene/conjugated estrogens improved symptoms of vulvar and vaginal atrophy, including dryness. In addition, bazedoxifene/conjugated estrogens improved vaginal lubrication, sexual function and menopause-related quality of life, when compared with placebo.

The incidences of breast pain and bleeding were less than five per cent and did not differ from placebo. There were no differences among groups in the incidences of adverse events and discontinuation rates. "Bazedoxifene/conjugated estrogens, if approved, will be a new and different therapeutic option that has the potential to change the way physicians and their patients treat menopausal symptoms and prevent postmenopausal osteoporosis," says Dr Constantine.

The efficacy and safety data for bazedoxifene/conjugated estrogens presented at this meeting represents only a portion of the totality of data available at this time.