A POTENTIALLY game-changing jab is being trialled in patients with prostate, lung and ovarian cancers. Together these claim 51,000 lives a year in the UK - almost a third of all cancer deaths.
Although we usually think of vaccines as preventing diseases, the term can also be applied to drugs that harness the power of the immune system to treat them.
This new vaccine directs the immune system to fight a protein that normally keeps cancer cells safe from harm.
Our immune system is constantly destroying small cancers as they develop. But cancer cells have a variety of strategies to avoid being attacked, allowing the disease to grow and spread. These include making a protein called survivin.
Found on the surface of the cells of many cancers in large quantities, it helps the cancer hide from the immune system.
Exactly how it does this isn't clear. One theory is that because it is also found on some healthy cells, albeit in much smaller amounts, the immune system doesn't realise the cancer cells are dangerous and so doesn't attack them.
The new vaccine, which has been developed by Oxford Vacmedix, a spin-out company from Oxford University, contains a synthetic form of survivin that's designed to stimulate a stronger response from the immune system. The hope is that this will destroy the cancer cells.
The jab, which is known as OVM-200, is being trialled on people for the first time, in a study involving up to 35 patients with cancer at University College Hospital in London and four other centres in the UK.
The participants will receive three doses of the vaccine, two weeks apart, and will be monitored for six months for changes in their cancer, as well as any side-effects.
The trial is focusing on three cancers, although it is hoped that the vaccine will be effective against multiple types of cancer.
Dr Martin Forster, a consultant in medical oncology at the UCL Cancer Institute and the trial's chief investigator, said: "Survivin is highly expressed in many cancers and therefore a great target for therapies such as this novel vaccine.
"This exciting UK-developed treatment introduces a new vaccine technology into clinical trials and has the potential to dramatically change outcomes for our patients. There is a huge unmet need and these are exciting times."
Commenting on the trial, Professor Raj Persad, a consultant urologist at Bristol Urology Associates, said: "New targeted treatments such as this promise to be much more specific and less toxic in their side-effects by simply boosting the body's own immune system."
But he adds that research into long-term side-effects and the treatment's impact on patient survival is "important before we rejoice too much".
"From initial studies, however, this approach looks very encouraging indeed," he adds.
© Daily Mail
