This will mark the beginning of a new era for the development of anti-cancer drugs

Dr Peter Rigby

The drug, known as Glivec, either shrank or completely stopped the growth of tumours in almost nine out of 10 patients who took it.

Even those with advanced forms of GIST - which causes weight loss, weakness and night sweats - benefited.

Abnormalities

The treatment works by seeking out molecular abnormalities in cancer cells and destroying them.

Dr Ian Judson, one of the scientists leading the trials, said: "The benefits of Glivec are overwhelming.

"Most striking is the speed of clinical improvement.

"These results could provide a glimpse of the future of drug development."

The benefits are overwhelming

Dr Ian Judson

The tests involved 40 patients, 36 of whom had GIST, and in all but four cases with the intestinal disease the tumour stopped growing or shrank.

They were carried out at the Royal Marsden Hospital in Fulham, west London, and two other centres in Europe.

Only around 1,000 patients a year in the UK suffer from GIST, which is a type of cancer known as a soft tissue sarcoma.

Treatment is normally limited to surgery, controlling symptoms, or palliative care.

Very exciting

Details of the drug are contained in the annual report of the Institute of Cancer Research and the Royal Marsden NHS Trust.

Cally Palmer, chief executive of the Royal Marsden, said: "The results from the trial are very exciting.

"For the first time these patients will be given a drug that shows excellent results without the harmful side effects of previous treatments."

Dr Peter Rigby, chief executive of the Institute of Cancer Research, added: "This will mark the beginning of a new era for the development of anti-cancer drugs."