A Canadian researcher involved in a study that uncovered a drug capable of significantly reducing the risk of breast cancer in high-risk, postmenopausal women calls the finding a “landmark” discovery. The American Society of Clinical Oncology announced that a massive international clinical trial has found the drug exemestane cuts the risk of cancer for such women by about two-thirds. Postmenopausal women with an increased risk of breast cancer, but who had not been previously diagnosed, who took part in the trial were 65 per cent less likely to contract the cancer than those who were given a placebo. The study also found that “no serious toxicities and only minimal changes in health-related quality of life” occurred in women taking exemestane. The findings were published in the New England Journal of Medicine on Saturday. The trial was funded by the Canadian Cancer Society and led by Canada’s NCIC Clinical Trials Group, and was known to participants as “ExCel.” The findings were the result of a massive international clinical trial, which included close to 250 Canadian women from 13 cities, including Vancouver, Winnipeg, Montreal, Ottawa and Toronto. Breast cancer is the most common cancer among Canadian women. The Canadian Cancer Society estimates that in 2011, 23,400 women will be diagnosed with breast cancer and 5,100 will die of it.