More than 1,000 patients are taking part in the TeloVac trial at 53 hospitals in the UK.
The vaccine – called GV1001 – aims to “prime” the body’s immune system to recognise and kill cancer cells, making chemotherapy more effective.
Cancer of the pancreas is difficult to treat and only 3% of patients live more than five years. About 7,600 people are diagnosed with the disease each year.
Smaller studies have found people given the vaccine, as well as chemotherapy, live three months longer than those given chemotherapy alone. Even then, they lived an average of just 8.6 months.
John Neoptolemos, director of the Liverpool Cancer Research UK Centre and a leader of the research, told The Times: “This will be a pivotal trial.
“If it’s successful, it would make a real difference to the way clinicians behave and patients are treated.”
GV1001, made by South Korean pharmaceutical company KAEL GemVax, contains a fragment of an enzyme called telomerase, which is normally found in human embryos and which cancer cells use to divide unchecked.
The vaccine teaches T-cells, a part of the immune system, to recognise cells that express telomerase – which in adults are all cancer cells – and attack them.
The results of the 1,110-person trial will be announced next autumn, and, if successful, a vaccine could be approved in late 2013 or 2014.
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