A trial looking at the immune system in men having radiotherapy for prostate cancer (Prostate Radiotherapy Pneumovax Study, or PRP)

Please note this trial is no longer recruiting patients.

The aim of this trial is to learn more about how radiotherapy affects the immune system in men with early prostate cancer.

Doctors sometimes treat prostate cancer that has not spread with radical radiotherapy and hormone therapy. But the treatment does not always work as well as doctors hope, and the prostate cancer can come back or spread to another area of the body. Researchers are hoping to find new ways of improving treatment for prostate cancer. They hope to be able to use the results of this study to develop a vaccine in the future.

Doctors know that radiotherapy can affect the normal cells of the immune system. To learn more about how the immune system works, everyone in this trial will have a vaccine usually used to protect against a common form of pneumonia (Pneumovax II vaccine). They will give blood samples so that the researchers can compare the reaction of their immune systems.

The men in the trial will be due to have radiotherapy for their prostate cancer, after starting hormone treatment. Blood samples will be taken from some men before they start radiotherapy and from others while they are having it. There will be a third group of similar aged men who do not have prostate cancer (the control group).

You will not have any direct benefit from taking part in this study. But, the results may help to improve prostate cancer treatment in the future.

If you are suitable for this study and are having treatment at Southampton General Hospital, you will be invited to take part.

Recruitment

Start 01/09/2007

End 02/11/2009

Phase

Pilot

Who can enter

You can enter this trial if you

Have been diagnosed with stage 1, 2 or 3 prostate cancer
Are having hormone therapy and are due to start radical radiotherapy

You cannot enter this trial if you

Have an illness that affects how well your immune system is working, or you are taking medicines that suppress your immune system
Have any other type of cancer
Have problems with your blood clotting properly
Do not have a spleen
Have problems with how well your kidneys or liver are working
Are allergic to any of the ingredients in the pneumococcal vaccine
Have had a pneumococcal vaccine in the last 10 years
Have had a vaccine containing diptheria toxoid in the last 6 months

Trial design

This study will recruit 30 men in total. The doctors in Southampton will invite 20 men who have recently been diagnosed with prostate cancer. They will also invite 10 other men of similar ages who do not have cancer, to use as a comparison. These people are known as the ‘control group’.

All the men with prostate cancer will have already started hormone treatment. They take this for 3 to 4 months, and then start radiotherapy. These men will be split into two groups for this trial.

If you are in group 1, the doctors will take a sample of blood shortly after you have started hormone treatment. You then have a pneumococcal vaccine, called Pneumovax II. You will have another blood test 4 weeks later to see if the vaccine has caused your immune system to make protective antibodies. You will go on to have treatment with radiotherapy as usual, over 4 to 7 weeks.

If you are in group 2, the doctors will take a sample of blood just before you start radiotherapy. They will also take blood samples

At the end of the first week of radiotherapy
During the final week of treatment
4 to 6 weeks after you finish treatment
4 months after you finish treatment

You have the vaccine after the last blood test. You will have a blood test 4 weeks after this to check the level of antibodies.

If you are in the control group, you will have a blood test and then the vaccine. You will have another blood test 4 weeks later.

For all groups, if you do not have a good enough response to the vaccine, your doctors will give you a similar vaccine called Prevenar. This protects against the same type of pneumonia as Pneumovax II, but it is usually given to children. You will have another blood test 4 weeks later to check your antibody levels.

Hospital visits

Your doctor will take your blood samples and give the vaccine on days that you are normally at the hospital, so you shouldn’t have any extra trips to the hospital.

If they are unable to fit in the blood tests with your normal treatment schedule, you may have to go to the hospital a couple of extra times to have them.

Side effects

As with any vaccine, you may have pain, redness and possibly swelling at the injection site. Some people may have flu like symptoms. These side effects should improve within a few days.

You may also get some discomfort when the needle is put into your vein to take the blood sample. There may be some mild bruising around the site, but this will clear after a week or two.