"Health wise I am feeling great. I am a big supporter of trials - it allows new treatments and drugs to be brought in.”
A trial of a vaccine treatment for prostate cancer that has come back (GTAC No 089)
This trial looked to see if a vaccine could stimulate the immune system to help treat prostate cancer that has come back. This trial was supported by Cancer Research UK.
Doctors usually treat prostate cancer with surgery, radiotherapy or hormone therapy. But sometimes the cancer continues to grow despite treatment. This trial looked at a type of vaccine treatment called a
Immune system cells can seek out and kill cancer cells, but they often don’t do this very well. Vaccines can help the immune system to do this. The vaccine in this trial helps cells in the immune system to spot a substance made by some prostate cancer cells called prostate specific membrane antigen (PSMA).
The trial looked at 2 ways of giving the vaccine. One was by injection into a muscle. The other was by injection into a muscle but with a short electrical pulse (called electroporation, or EP) at the same time.
The aims of this trial were to find out
- If this DNA vaccine stimulates the immune system
- More about the side effects
Summary of results
The research team found that the vaccine was safe and did stimulate the immune system.
The trial recruited 32 people to have the vaccine and another 32 people as the control group who didn’t have the vaccine.
Those who had the vaccine had 5 injections into their thigh muscle over about 11 months. The trial team were able to assess 30 people in the vaccine group - 15 had the injections alone and 15 had the injections at the same time as a short electrical pulse (electroporation).
The research team measured the number of T cells (called CD4 and CD8 cells) in blood samples to see if the vaccine had stimulated the immune system.
They found that the vaccine did cause the immune system to make more CD4 and CD8 cells. The people who had electroporation with the injection had slightly higher levels of immune cells than those who the injection on its own. But it’s difficult to be sure of the effect of electroporation (EP) because most people having the injection alone swapped to having EP as well for the last 2 doses.
Doctors often measure the level of prostate specific antigen (PSA) to see how well treatment is working. One way to do this is to see how quickly the PSA level doubles. The research team found that the PSA doubling time in the control group was nearly 12 months. In the vaccine group it was nearly 17 months. This suggests that the cancer grew more slowly in the vaccine group.
The vaccine did cause some side effects, but these were mostly mild. They included soreness at the injection site, flu like symptoms, back pain and nail changes.
The research team concluded that this DNA vaccine was safe to use and that bigger trials should be done to find out more about it.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor Christian Ottensmeier
Professor David Dearnaley
Allan Willett Foundation
Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
Institute of Cancer Research (ICR)
The Royal Marsden NHS Foundation Trust
University Hospital Southampton NHS Foundation Trust
University of Southampton