Study: New breast cancer drug saves lives

A new class of breast cancer drug that women can take after the standard five years of tamoxifen therapy saves lives as well as prevents the return of tumors, researchers from Canada reported on Tuesday. Femara, made by Swiss drugmaker Novartis, reduced the risk of death by 39% in women who took it, compared with women who took a placebo. It reduced the spread of cancer, called metastasis, by 4%, the researchers told a meeting of the American Society of Clinical Oncology in New Orleans. The findings add to the evidence that the drugs, called aromatase inhibitors, are a valuable extra weapon in the arsenal against breast cancer, which will affect 1.2 million people globally this year and kill 40,000 in the United States alone. For the study, Paul Goss, from Princess Margaret Hospital in Toronto, has been studying 5,100 women who took the standard treatment, tamoxifen, for five years. Tamoxifen cuts the risk of breast cancer in half and greatly reduces the risk that it will come back in women who have already had one bout with the disease. Goss and his colleagues reported last year that Femara, known generically as letrozole, reduced even further the risk that breast cancer would return in women who took it after taking tamoxifen. "We in fact did reduce internal metastases, which are inevitably fatal," Goss said in a telephone interview. "We also reduced the risk of dying. We have a survival advantage for women taking this drug." Among women taking Femara, 28 died of breast cancer during the study. Among women taking the placebo, 45 died. The women took the drug for a median of 2 1/2 years. Goss said the drug seemed safe, but there is a concern that Femara seems to increase the risk of the bone-thinning disease osteoporosis. "There is an apparent slight increase in bone loss," he said. "A slightly increased number of women developed osteoporosis during the trial. But there was no difference in fractures. At least we know about it, and it is easy to fix and prevent. There will be some women in whom cancer is such a low risk and whose risk of osteoporosis is so high that this drug might not be suitable." Aromatase inhibitors, including the existing medication Arimidex, made by AstraZeneca, work through a different mechanism from tamoxifen by reducing the effects of estrogen, a hormone that can fuel tumor growth. (Reuters)