New Breast Cancer Drug Tops Tamoxifen
March 27, 2002 -- Tamoxifen, the current gold standard for hormone treatment of breast cancer, has lost yet another challenge from a new drug. New research shows Arimidex is better at preventing cancer recurrence and saving lives than tamoxifen.
Studies presented at a meeting of breast cancer specialists show that Arimidex is better at reducing the risk of breast cancer developing in the other, healthy breast in postmenopausal women who have survived breast cancer. And Arimidex also gives advanced breast cancer patients a survival advantage over tamoxifen.
The first study involved more than 6,200 postmenopausal breast cancer survivors. Those who took Arimidex had a 58% lower risk of developing a tumor in the other breast compared with those taking tamoxifen. Researchers say women successfully treated for early breast cancer are still three times as likely to develop a new tumor in the opposite breast compared with women who have not had breast cancer.
Since tamoxifen has already been shown to reduce this risk by 50%, cutting this risk again by half is exciting news, researchers say.
"To find a treatment that cuts this risk in half again is truly remarkable -- and welcome news for the millions of postmenopausal women diagnosed with early breast cancer every year," says study researcher Jeffery Tobias, MD, oncologist at the University College Hospital in London, in a news release.
The study also found that Arimidex was better tolerated than tamoxifen and produced fewer side effects and complications such as uterine cancer, vaginal bleeding, blood clots, and hot flashes.
A second study presented at the same conference found Arimidex also had the edge over tamoxifen in helping women with advanced breast cancer live longer. Researchers say it's the first time any drug has shown a survival benefit over tamoxifen in these patients.
Arimidex is part of a new class of drugs known as aromatase inhibitors, which also includes the breast cancer drug Femara. They work by blocking the use of estrogen that some types of breast cancer need to grow.
Arimidex is currently approved for use as a first and second-line treatment for advanced breast cancer in postmenopausal women. Its maker, AstraZeneca, has applied to extend this indication for use in treating postmenopausal women with early-stage breast cancer.