A drug used in the treatment of osteoporosis may provide breast cancer sufferers with cause for celebration.
Following four-year trials on some 20,000 women, raloxifene was found to lower the risk of invasive breast cancer by 50 per cent, the same figure as tamoxifen, the only drug that is currently approved in the US for that use.
However, the trials, sponsored by the National Cancer Institute, found that raloxifene resulted in 36 per cent less uterine cancers and 29 per cent fewer blood clots in women compared to tamoxifen.
"It will be very important for women with an increased risk of breast cancer to make an informed decision with the advice of their physician," the American Cancer Society said in a statement.
"It is also important to note that while both drugs can prevent many breast cancers, neither has been shown to reduce the risk of death due to the disease."
Raloxifene is set to undergo further tests for its effectiveness on post-menopausal women.