Cancer patients were treated with a vaccine in the trial
A vaccine which uses the body's immune system to attack an aggressive form of kidney cancer has completely eradicated one patient's tumour.
The TroVax vaccine, made by Oxford Biomedica, has been given to 150 patients so far in clinical trials.
Another two patients have seen their tumours shrink, and a further 15 have been stable for at least three months.
UK cancer experts said the data, presented at a conference in Prague, showed TroVax was effective.
Around 6,600 people are diagnosed with kidney cancer each year in the UK. In 2004, 3,600 people died from the condition.
The TroVax vaccine is still going through the clinical trials process.
It works by harnessing the body's immune system to tackle a tumour.
A protein called 5T4 is present on the surface of around 90% of kidney tumours, but not on healthy cells.
The patient is given a series of injections containing a harmless virus and a gene for the 5T4 protein.
This gene triggers an immune reaction which leads the body to attack the cancer cells.
The treatment involves seven injections over 41 weeks, given alongside standard cancer therapy.
Quality of life
The patient who saw his tumour completely disappear was given the vaccine plus a drug called IL-2, already given as standard treatment for kidney cancer.
Of the 15 patients whose disease stabilised, one has been stable for 46 weeks.
A further 700 patients will now receive the treatment as the vaccine undergoes further study.
The Phase III trial will compare TroVax plus standard kidney cancer treatment and a dummy version plus standard treatment.
Researchers will look at whether or not tumour shrink, if the progression of the disease can be halted and patients' quality of life.
Professor Robert Hawkins, of Christie Hospital in Manchester who will be leading the study, said the data so far on the vaccine was "very encouraging".
"It would be rare that a patient would get rid of a tumour with standard treatment.
"The fact that it has happened in a relatively small trial is encouraging."
Dr Daljit Kaur, clinical trials research manager at Cancer Research UK, said: "We're very pleased that TroVax has entered phase III clinical trials for treating kidney cancer.
"The data so far suggests TroVax could be an effective treatment for several types of cancer, including kidney cancer, which affects more than 6,600 people each year in the UK."
Oxford Biomedica hope the vaccine will be available for use by the end of the decade.