AstraZeneca cancer 'breakthrough'

A POWERFUL new breast cancer drug made by AstraZeneca has been hailed as 'the biggest step forward in 20 years' in fighting the disease. Experts say the drug, called Arimidex, greatly improves cancer victims' chances of survival and could save thousands of lives.

Women diagnosed with early tumours could be taking it as a daily pill by the end of the year. Research findings to be revealed today suggest that Arimidex could prevent three-quarters of them from suffering a relapse. It appears to work significantly better than tamoxifen, the current 'front-line' drug.

Breast cancer is the most common cancer among women in Britain, affecting about one in ten. There are 39,500 new cases each year and 13,000 deaths.

Though Arimidex is about ten times more expensive than tamoxifen, the cost of £1,000 for a year-long course is less than many other drugs. Beta interferon, for example, to be used to treat 9,000 multiple sclerosis sufferers, costs between £5,000 and £10,000. The overall cost to the NHS would also be reduced because Arimidex does not produce the same level of side- effects needing expensive treatment.

Tamoxifen, developed two decades ago, is used to stop patients who have been successfully treated with surgery from developing a new tumour in the other breast. It has helped cut death rates by a third and is estimated to have saved hundreds of thousands of lives.

But the latest research findings, from the largest cancer trial ever undertaken, show that post-menopausal women who took Arimidex daily for two and a half years after surgery were 77% less likely to develop cancer in the unaffected breast. Using tamoxifen over a similar period cut the risk by 54%.

Dr Jeffrey Tobias of University College Hospital, London, who is one of the trial investigators, called the results 'exceptional'. 'The reduction in the development of new cancers was very much greater than we had anticipated,' he said. 'This is the first time a large-scale clinical trial has proved another treatment superior to tamoxifen. It marks an important breakthrough in the management of this devastating disease and will be very welcome news for the thousands of post-menopausal women diagnosed with early breast cancer each year.'

The international trials of the new drug involved more than 9,300 women, 3,000 of them from the UK. The results will be released today at a conference in Florida of the American Society of Clinical Oncology.

Arimidex was also found to be more likely to prevent cancer recurring in the same breast or elsewhere in the body after surgery. Overall, women taking the new drug were about 20% less likely to suffer any sort of relapse.

The study also suggests that Arimidex has fewer side-effects than tamoxifen, which carries a small but significant increased risk of cancer of the womb lining. There is about one case in every 200 women using the drug, but Arimidex reduces the risk to around one in every 1,000. It also halves the rate of other problems.

Arimidex is currently licensed for treatment of early breast cancer only in Japan, but AstraZeneca expects early approval of their application for an EU licence.