Drug helps
prevent breast cancer—but has tradeoffs

A trial of Eli Lilly's osteoporosis drug Evista found that patients given the treatment had a reduced incidence of bone fractures and breast cancer but were more likely to suffer fatal strokes and blood clots.

The study of some 10,000 women also dashed hopes of some physicians that the drug would offer substantial protection against heart attack to women in the highest risk groups.

Doctors had thought that the drug, known generically as raloxifene and used to treat the bone-thinning disease osteoporosis, might help prevent heart problems because it lowers cholesterol and improves other indicators of heart-disease risk. But after giving either the drug or a placebo to the women for an average of 5.5 years, the research team led by Elizabeth Barrett-Connor of the University of California, San Diego, found that the medicine had no effect on the incidence of heart attacks, heart failure, or death from heart-related causes.

Results of the trial appear in this week's New England Journal of Medicine. Half of the participants were treated with Evista, while the other half got an inert placebo.

The study found that Evista has mixed benefits and risks related to other diseases.

Among every 1,000 women taking the drug for 10 years, the study concluded that Evista would prevent 12 cases of invasive breast cancer, cutting the risk of that kind of cancer by 44% versus women taking a placebo. The results also found that it would prevent 13 spine fractures, a 35% reduction in risk.

The study's authors said that among every 1,000 women on the drug, seven more would have fatal strokes than those on placebo, increasing the risk by 49%. Twelve more would have dangerous blood clots known as venous thromboembolisms, increasing the risk by 44%, they said

The researchers advised doctors to weigh the risks and personal preferences of each patient before deciding whether to prescribe raloxifene, which affects the way the body deals with the female hormone estrogen.

"There is not a magic bullet that can reduce the risk of major health problems related to estrogens and aging without introducing other potentially serious health concerns," Marcia Stefanick of the Stanford School of Medicine, said in an editorial that appeared in the journal.

The study included some 10,101 postmenopausal women over age 54 at 177 sites in 26 countries. All faced an above-average risk of heart disease, although none had experienced a heart attack or had surgery to prevent one. (Reuters)