Drug that uses the body's cells to blast cancer

The 'serial killer' treatment completely eliminated some tumours and shrunk others resistant to existing therapies.

Further successful trials could lead to blinatumomab being on the market in less than five years.

The drug, blinatumomab, which was developed to treat non-Hodgkin's lymphoma, glues cancer-killing white blood cells called cytotoxic T cells to the tumour

The tests were carried out on patients with non-Hodgkin's lymphoma, but it is hoped the methods can be adapted to tackle other cancers.

The results have been described as an 'exciting' development in the use of immunotherapy, the process of using the body's own immune system to fight disease.

The drug treats non-Hodgkin's lymphoma - a cancer of the immune system - by glueing cancer-killing white blood cells called cytotoxic T cells to the tumour.

Once there, they release a poison that destroys the cancer.

Sufferers of non-Hodgkin's lymphoma include Michael Aspel, who was diagnosed with a slow-growing form of the disease in 2003

Researcher Dr Patrick Baeuerle said: 'These cells circulate in our body stuffed with ammunition - little vesicles filled with toxins.

'It is just a matter of attaching them to the tumour cells and making them fire.

'The drug tickles the T cell in a very special way so that it fires and won't stop firing until the tumour cells have gone. It turns them into serial killers.'

Professor Peter Johnson, Cancer Research UK's chief clinician, said: 'These exciting preliminary results come from using them to harness the body's own immune response in a new way.

'Although the side effects need to be monitored carefully, we hope that this type of treatment will prove to be active in larger trials in the future.'

Dr Baeuerle gave the drug to 38 people who had stopped responding to conventional treatments for non-Hodgkin's lymphoma, a disease that affects 10,000 Britons a year and kills almost 4,500.

In four cases, the tumours were eliminated, with one patient still cancer-free more than a year later.

In another seven cases, the tumours shrunk considerably, the journal Science reports.

Dr Baeuerle, of Micromet, the German biotech company developing the drug, said: 'All the patients we treated had run out of therapy options, they were considered incurable.

'This study could potentially offer something new to patients and give them a longer time to live or other improvement.'

The drug is now being tested on patients with an aggressive form of blood cancer and similar compounds are being developed to tackle other cancers.

Sufferers of non-Hodgkin's lymphoma-include Michael Aspel, who was diagnosed with a slow-growing form of the disease in 2003.

For reasons that are not understood, the number of cases has been slowly but steadily rising for the last 50 years.

If the trend continues, it could be as common as breast or lung cancer by 2025.

Dr Cassian Yee, of the Fred Hutchinson Cancer Research Center, Seattle, who has had significant results using an alternative method of treating patients with white blood cells grown in the lab, said: 'This a significant study.

'It remains to be seen if most of the responses are long lasting. Certainly the results are very promising.'