An innovative cancer drug that works by starving tumours of oxygen and nutrients has been approved for use in the US and could be available in Britain in a year.

Avastin was fast-tracked in the US because of outstanding results from a trial of patients with advanced bowel cancer.

The drug is the first to effectively cut off the blood supply to tumours. It targets the mechanism, known as angiogenesis, by which tumours build a network of blood vessels.

The US study involved more than 900 patients whose bowel cancer was spreading. They were given Avastin together with standard chemotherapy, or conventional treatment alone.

Avastin increased survival by a mid-range figure of about five months. Such an improvement is virtually unheard of in this group of patients. The drug also produced few side-effects.

Roche, the maker of Avastin, is in negotiations with drug regulatory authorities in Europe. An application to license Avastin in Europe was filed in December, and a Roche spokeswoman said the licensing process might take "about a year".

Roche is investigating Avastin in treating a number of other forms of cancer, including lung, pancreatic, breast and kidney. Large clinical trials are under way in patients with bowel cancer that has not spread. The spokeswoman said: "Anti-angiogenesis treatment has been a bit of a holy grail. The concept of starving the tumour of blood has been around for a long time, but this is the first drug of this type to show real benefit for patients."