New drug protects from cancer for longer

THE manufacturers of Arimidex, a rival drug to frontline breast cancer drug tamoxifen, claim their product helps women live cancer-free for longer.

Announcing the results of a 100-month study of postmenopausal women with early breast cancer, Arimidex maker AstraZeneca claimed their product had a longer-lasting protective effect than tamoxifen in reducing the risk of cancer returning.

This protective effect in reducing the risk of hormone-sensitive early breast cancer from recurring continues to increase even four years after a woman’s breast cancer treatment has ended, AstraZeneca claimed.

The data in relation to Arimidex (trade name for anastrozole) was released yesterday at the annual San Antonio Breast Cancer Symposium, US, and published online in The Lancet Oncology. The data was compiled as part of the ATAC (Arimidex, Tamoxifen, Alone or in Combination) multinational study.

More than 40 Irish women were involved in the trial at three Irish centres as well as Proffessor Tom Gorey, a consultant breast/endocrine surgeon, at the Mater Hospital, Dublin. Yesterday Prof Gorey said the new data in relation to Arimidex “confirm long-term that anastrozole continues to be more effective than tamoxifen for postmenopausal women with hormone-sensitive early stage disease — thus it is desirable that these women get the most effective hormonal agents at the outset”.

Prof Gorey said the primary goal in breast cancer management was preventing recurrence.

“The longer we can delay cancer recurrence, the more lives can be saved,” he said.

He said that while prior to the ATAC trial, tamoxifen was the standard of care for women with hormone-sensitive disease, the data confirmed that compared with tamoxifen, anastrozole significantly reduces the risk of recurrence while minimising life-threatening side effects.

“Most encouragingly, the data also shows us that the protective effect of anastrozole lasts beyond the standard treatment period of five years and in my opinion confirms that it is better than tamoxifen as a first-line option in postmenopausal women,” Prof Gorey said.

According to AstraZeneca, overall, women in the ATAC trial taking anastrozole were 24% less likely to have their cancer come back, compared with those taking tamoxifen.

Breast cancer affects more than 2,000 women a year in Ireland and hormone-sensitive early disease accounts for about 75% of all cases of breast cancer in postmenopausal women.