Wyeth says a new approach to treating 40 million American women with menopause may generate $5 billion in annual revenue and replace sales lost when its hormone therapies were discredited five years ago.
Sales of Wyeth’s Premarin and Prempro hormones evaporated following a U.S. study in 2002 linking the pills to breast cancer, heart attacks and strokes. The Madison, New Jersey, drugmaker is trying to revive its women’s health-care unit with three experimental medicines for debilitating symptoms of menopause, such as hot flashes and brittle bones.
The first of these new drugs, Pristiq, is set for U.S. regulatory review in July. Pristiq, a reformulation of Wyeth’s Effexor antidepressant, tempers hot flashes while avoiding side effects tied to hormone use.
“Pristiq is an exciting new class,” said JoAnn Pinkerton, professor of obstetrics and gynecology at the University of Virginia in Charlottesville. “It will give an option to women who have been so frightened of hormone therapy that they suffered through menopause symptoms without taking anything at all.”
U.S. prescriptions for Premarin and Prempro, which include synthetic versions of two female hormones, dropped by 73 percent to 18.5 million last year from 67.2 million in 2000, the company said.
The U.S.-funded Women’s Health Initiative study reported in 2002 that hormone-replacement therapies carried life-threatening side effects. Since then, Wyeth’s sales of the drugs have tumbled.
Last year, Wyeth reported sales of $1.1 billion from Premarin and Prempro, 6.5 percent of total drug revenue. In 2001, before the study results raised alarms, Wyeth’s hormone sales were more than $2 billion, or 17 percent of pharmaceutical revenue.
“Menopause products could become our biggest franchise again,” said Joseph Mahady, president of Wyeth Pharmaceuticals, in a telephone interview.
Wyeth will report the results of four studies on Pristiq next week at a meeting of the American College of Obstetricians and Gynecologists in San Diego. The company’s shares rose 37 cents to 41.48 euros ($56.46) at 11:57 a.m. in Germany after closing yesterday at $55.83 in New York. The stock has gained almost 10 percent this year.
Like Effexor, Pristiq boosts levels of two naturally occurring brain chemicals, serotonin and norepinephrine. Doctors have used Effexor for menopause as an off-label prescription, or use not approved by the U.S. Food and Drug Administration. Research has shown that symptoms such as hot flashes are related to a deficiency of serotonin, which regulates body temperature.
Role of Brain
Reduced estrogen levels during menopause cause the part of the brain responsible for temperature control to malfunction, doctors say. Hot flashes strike suddenly and can be accompanied by a rapid heart beat, nausea, dizziness, headaches, muscle weakness and fatigue.
Physicians have prescribed Effexor and other drugs in its class, known as SSRIs, or selective serotonin reuptake inhibitors, most often to treat hot flashes in women with breast cancer, said David Archer, professor of obstetrics and gynecology at Eastern Virginia Medical School in Norfolk.
“SSRIs have been used off-label for the last few years to treat menopause symptoms in women who have breast cancer and in other patients who are uncomfortable with the idea of taking hormones,” said Archer, author of one of the Wyeth-funded studies on Pristiq being reported at next week’s medical meeting.
Two More Drugs
In early studies, Pristiq has significantly reduced the severity and frequency of hot flashes associated with menopause, Wyeth said. The company has projected annual revenue of $2 billion for Pristiq.
Viviant, a selective estrogen receptor modulator, or SERM, treats bone loss in post-menopausal women. An initial regulatory application for Viviant was delayed last week because the FDA requested more data about how it works and how it will be made. Wyeth said it expects an FDA decision on the drug by 2008.
About 8 million U.S. women have osteoporosis, or bone density loss, and 22 million more are at risk for developing it, Wyeth said. Reduction of the hormone estrogen during menopause is the major cause of bone-loss in women.
A third new drug, Aprela, combines the active ingredient in Viviant with estrogen to relieve a wider range of menopause symptoms, including hot flashes and vaginal dryness. Wyeth plans to apply for U.S. approval of the drug this year, and may get a decision from the FDA by the end of 2008. Combined sales of Viviant and Aprela may top $2 billion a year, Wyeth said.
Patients are now taking lower doses of Premarin and Prempro to limit their exposure to the hormones. Prempro is a combination pill that uses progestin to reduce the risk of uterine cancer that is linked to using estrogen alone. Premarin, an estrogen- only pill, is given to women who have had hysterectomies, or removal of the uterus.
Women continue to use Wyeth’s older hormone replacement therapies in part because there isn’t a more effective alternative on the market, said Michelle Warren, a professor of obstetrics and gynecology at Columbia University Medical Center in New York.
“We tell women to take the lowest dose of hormones possible for the shortest period of time,” Warren said. “The new drugs without hormones offer a promising alternative.”