Breast Cancer Drug Femara Beats Tamoxifen
Better Survival Rates After Surgery and Menopause, Says Drugmaker
WebMD News Archive
Jan. 27, 2005 -- Postmenopausal women with early breast cancer have fewer
recurrences after surgery when they take Femara instead of tamoxifen, new
The results were announced at the Primary Therapy of Early Breast Cancer 9th
International Conference in Switzerland. Femara's maker, Novartis, funded the
study. Novartis is a WebMD sponsor.
The study posed a key question: Which drug is better at reducing the risk of
breast cancer's return in postmenopausal women who have had breast cancer
Survival More Common
The issue affects thousands of women. It's becoming more common to survive
There are more than 2 million U.S. women who are breast cancer survivors,
says the American Cancer Society (ACS).
This year, more than 211,000 U.S. women will be diagnosed with breast
cancer, the ACS estimates. About 40,000 will die of the disease. For survivors,
keeping cancer at bay is a top priority.
More than 8,000 women in 27 countries participated in the study. All had
undergone breast cancer surgery and were postmenopausal. Their breast cancer
was treated early; it hadn't spread beyond the breast and lymph nodes.
The women's tumors were dependent on the hormone estrogen to grow. About
two-thirds of breast cancers are fueled by estrogen, says the ACS.
Typically, women take tamoxifen for about five years. About 500,000 U.S.
women take tamoxifen and 80,000 join their ranks each year.
How the Drugs Work
Femara and tamoxifen both lower the amount of estrogen in the body, slowing
the growth of estrogen-dependent tumors. But they work differently.
Tamoxifen blocks estrogen receptors. It's the standard treatment for
postmenopausal women with estrogen-dependent tumors. Tamoxifen was a major
breakthrough when it debuted more than 25 years ago. It's also used to prevent
breast cancer in women at high risk for the disease.
Femara takes a different approach. It's the second in a newer class of
breast cancer drugs called aromatase inhibitors.
Aromatase inhibitors target aromatase, which is needed to turn male-type
hormones called androgens into estrogen. Thwarting aromatase prevents androgens
from morphing into estrogen. As a result, estrogen levels are lower.