Drug switch helps breast-cancer patients

WASHINGTON, Aug 04, 2005 (United Press International via COMTEX) -- Postmenopausal women with early breast cancer do better when they switch from Tamoxifen to another drug after two years of treatment, a new study found. It is the latest research to suggest the benefits of a new class of drugs in fighting breast cancer.

Tamoxifen has been the leading breast-cancer treatment for two decades, but recent studies have shown the promise of a new class of drugs called aromatase inhibitors.

The study, by scientists in Germany and Austria, is in the new issue of the British journal The Lancet. The researchers looked at data on one of the new drugs, anastrozole, in two randomized trials in which it replaced Tamoxifen after two years in postmenopausal women with hormone-responsive early breast cancer.

The study found a 40-percent decrease in the risk for a recurrence of cancer in the other breast or spreading to another part of the body. Sixty-seven of 1,618 women on anastrozole had such events, compared with 110 of 1,606 women who stayed on Tamoxifen.

"Although further investigation is necessary to ascertain the ideal sequence and duration ... this combined analysis confirms that post-menopausal women who receive Tamoxifen should be switched to anastrozole after two years of treatment," Professor Raimund Jakesz of Vienna Medical University said in a statement.

In a comment that accompanies the article, Anthony Howell of Christie Hospital in Manchester, England, added, "The aromatase inhibitors show superiority over Tamoxifen when used immediately after surgery or after two to three years of Tamoxifen."

Last month a British market-analysis firm predicted that revenue from aromatase inhibitors will nearly double in the next decade.

"The advent of aromatase inhibitors from AstraZenica, Novartis and Pfizer has reignited opportunities for treatment in breast cancer," said Dr. Richard Faint, of Datamonitor in London, which conducted the analysis.

"Tamoxifen has been the gold standard for many years now, and it's very successful," Faint told United Press International, "but aromatase inhibitors are probably going to knock Tamoxifen off its perch with postmenopausal women with breast cancer."

He said he expected Tamoxifen to remain a treatment option.

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