Wyeth hot flashes drug succeeds in trial-research

NEW YORK Oct 5 (Reuters) - An experimental Wyeth WYE.N drug used in combination with estrogen quickly and effectively reduced the number of hot flashes in post-menopausal women without causing changes to the uterus that raise the risk of uterine cancer, researchers said on Friday.

Researchers said results of the late-stage trial for Wyeth's drug bazedoxifene were promising because estrogen, the female hormone that is highly effective in blocking hot flashes, can raise the risk of uterine cancer when it is used by itself.

Estrogen's risk of causing uterine cancer for years has been minimized by having patients also take an older Wyeth drug called protesterone, sold under the brand name Prempro.

But Prempro has fallen into disfavor since a 2002 federally sponsored trial showed that long term use of it raised the risk of breast cancer, even though it may protect against uterine cancer.

Bazedoxifene, a new member of the family of drugs called selective estrogen receptor modulators (SERMs), was tested among 332 postmenopausal women with serious hot flash problems, defined as having more than 50 hot flashes a week.

Patients were divided into groups that received the Wyeth drug in combination with either with a standard full dose of estrogen or a somewhat reduced dose.

After 12 weeks of treatment, patients taking bazedoxifene and full-dose estrogen reported 80 percent fewer hot flashes, while those receiving the lower dose cited 74 percent fewer incidents, said Dr. JoAnn Pinkerton, an associate professor of obstetrics and gynecology at the University of Virginia who led the trial.

The results were highly statistically significant, compared with the 51 percent fewer hot flashes reported by the placebo group.

Although the results were promising, she said a definitive picture of safety for the new drug combination would emerge only after longer-term review of patient trends.

Pinkerton, who has served as a paid consultant to Wyeth, said combined use of estrogen and bazedozifene did not stimulate production of cells in the uterus that can turn into cancer.

"Bazedoxifene could provide a new option for those who want to avoid the side effects of estrogen and progesterone," Pinkerton said.

Pinkerton said patients receiving the bazedoxifene/estrogen combination reported sustained symptom relief within 14 days of beginning therapy, compared with 30 days for those taking placebos.

She said those taking the drug combination also had a very statistically significant improvement in time to fall asleep, and in feeling rested after sleep.

Bazedoxifene is also awaiting U.S. marketing approval to prevent osteoporosis, and if approved for that indication would compete with Evista, a SERM sold by Lilly and Co. (LLY.N).

Another drug Wyeth had hoped to sell for hot flashes, Pristiq, had a major setback in July when U.S. regulators said they could not approve it until the company did more tests on its potential heart and liver risks.

Pristiq is a derivative of Wyeth's widely used Effexor anti-depressant.