Scientists are planning to start human trials next year

British researchers have developed a drug which can dramatically slow down the progression of the disease in mice.

The drug differs from existing treatments in that it uses leukaemia DNA to help the immune system to identify and target cancer cells.

Writing in the journal Nature Medicine, the scientists said it may provide "a new approach" against the disease.

Survival rates for leukaemia have improved dramatically in recent decades. However, the disease still claims many lives.

DNA approach

The drug, developed by Dr Rose Ann Padua and colleagues at Kings College Hospital in London, includes pieces of DNA that provide the coding for a protein found in cancer tumours.

The scientists injected their drug into a group of mice with acute leukaemia.

This appears to be a very good approach for fighting not only this particular type of leukaemia but also a whole range of other cancers Professor Freda Stevenson, University of Southampton

They found that it triggered antibodies to the cancer cells and had "a pronounced effect" on survival.

They reported that the drug was even more effective when given in combination with ATRA, a drug currently used to treat this type of leukaemia.

Six out of 12 mice which had received both treatments were alive after 120 days.

All of the mice which had received only ATRA had died by day 85.

The researchers said their DNA drug could eventually be used with existing therapies to help human patients to stay in remission longer, boosting their chances of beating the disease.

"When DNA vaccination and conventional ATRA therapy are combined, they induce protective immune responses against leukaemia progression in mice and may provide a new approach to improve clinical outcome in human leukaemia," they wrote.

The researchers are now planning to test the drug on humans.

"We are hoping to start human clinical trials next year," Dr Padua told BBC News Online.

"Basically, we are ready. This is the first time a DNA vaccine has been targeted at the cancer cell."

Professor Freda Stevenson of the University of Southampton, who has carried out extensive research in this area, welcomed the study.

"It is very important," she told BBC News Online.

"This appears to be a very good approach for fighting not only this particular type of leukaemia but also a whole range of other cancers."