AstraZeneca's breast cancer drug Arimidex has been cleared by the European medicine regulators, for use as a new treatment option, in women suffering from post menopausal early breast cancer, who are currently taking the hormonal treatment tamoxifen.
Arimidex was earlier licensed only for use directly following breast cancer surgery in women with newly detected breast cancer to stop the cancer from returning. It is part of a group of drugs called aromatase inhibitors and is taken as a once a day pill.
The new license allows Arimidex to be made available to women, both for primary adjuvant use, and also to women who have already undergone a partial course of the earlier “gold standard” treatment tamoxifen which was used first in 1969.
The new license granted to Arimidex also takes effect in the European Union Mutual Recognition markets: the UK, Austria, Germany, Portugal, Italy and Spain.
Clinical studies have already proven Arimidex to be considerably more effective as compared with tamoxifen in preventing the relapse of early stage breast cancer in post menopausal women. Those who switched to Arimidex from tamoxifen could improve disease free survival rate by 65 percent, were less likely to suffer a relapse and experience fewer side effects.
Professor Walter Jonat of University of Kiel, Germany said that physicians were increasingly using anastrozole at diagnosis because of its superior efficacy and tolerability compared with the old gold standard tamoxifen. “The question remained whether those patients who did not receive anastrozole from the start of their treatment would still be able to
benefit. This new indication means we can now also offer them a greater likelihood of
living longer, cancer free, by changing therapy to anastrozole. It will also reduce the
risk of patients experiencing some of the long-term side effects associated with
tamoxifen," he said.
Arimidex works in a very different way as compared to tamoxifen. . Tamoxifen interferes directly with the cancer cells' ability to use estrogen for fuel to divide and grow while Arimidex blocks the production of estrogen from the adrenal glands (near the kidneys) which is a main source of estrogen for post-menopausal women.
Dr Emma Pennery, who is a nurse consultant with charity Breast Cancer Care, said many women who were fearful of their cancer returning would be extremely pleased to hear of the latest addition to the range of treatment options currently available.
