A trial of a vaccine called PROSTVAC for prostate cancer

This trial is looking at a new vaccine called PROSTVAC for prostate cancer that has spread.

If prostate cancer has spread outside the prostate gland, doctors often treat it with hormone therapy. This can work very well, but at some stage the cancer may start to grow again. This may not cause symptoms, but your doctor might see changes on a scan or there may be an increase in the level of PSA in your blood.

The immune system can recognise and kill cancer cells. But it is not always very good at doing this. In this trial, researchers are looking at a vaccine called PROSTVAC that can help the immune system to recognise and attack prostate cancer cells.

GM-CSF is a type of growth factor. Growth factors are proteins made in the body and some of them make the bone marrow produce blood cells. GM-CSF makes the body produce white blood cells. The researchers want to find out if giving GM-CSF alongside the vaccine can help it to work better.

The men taking part in this trial have prostate cancer that scans or blood tests show is getting worse. But their cancer is not causing symptoms or only causing very mild symptoms. The researchers will compare men in 3 groups

• PROSTVAC alongside GM-CSF

• PROSTVAC alongside a dummy drug (placebo)

• PROSTVAC dummy drug alongside GM-CSF dummy drug

The aims of the trial are to

• See if either PROSTVAC alone or PROSTVAC alongside GM-CSF is better than a dummy drug to help men with prostate cancer live longer

• Learn more about the side effects