A trial of a new class of breast cancer drugs has resulted in the reduced recurrence of the disease in order women who had already taken the standard treatment, researchers reported today.
Their report, published in The New England Journal of Medicine, showed that Femara, made by Swiss drugmaker Novartis, lowered the risk of cancer recurrence by 43 per cent in women past menopause. Researchers stopped the trial so all the patients could take the drug.
Femara, known generically as letrozole, belongs to a new class of breast cancer drugs called aromatase inhibitors. AstraZeneca also has a drug of the same type, called Arimidex.
Dr Paul Goss of Princess Margaret Hospital in Toronto and a team of researchers across the United States and Canada were testing Femara in women who had already completed the standard treatment for many cases of breast cancer - five years of tamoxifen.
They wanted to see if adding the once-a-day pill helped keep the cancer from coming back.
Half the 5,000 women in the trial got Femara and half got a placebo. After just over two years, 207 of the women had their cancer return - 75 who got Femara and 132 who got the placebo.
"At a median follow-up of 2.4 years, the women in the Femara group showed a 43 per cent reduction in risk of recurrence compared with placebo," Novartis said in a statement.
"The results also showed that Femara reduced the risk of contralateral disease -- cancer recurrence in the other breast - by 46 per cent."
The researchers said 42 women who got the placebo died and 31 women who got Femara died.
"As compared with placebo, letrozole therapy after the completion of standard tamoxifen treatment significantly improves disease-free survival," the researchers wrote in their report, to be published in November.
"The news is significant because in more than 50 per cent of women treated for breast cancer, the cancer recurs five or more years after their original diagnosis," the City of Hope National Medical Center in Duarte, California, where researchers worked on the study, said in a statement.
The Journal broke the news early because of the significance.
Novartis's share price was up 2.4 per cent, to 52.65 Swiss francs a share, in late afternoon trading.