A study looking at 2 new treatments for prostate cancer that does not respond to hormone therapy

This study is to see if 2 drugs for diabetes and high cholesterol help reverse rising PSA levels in symptom free hormone resistant prostate cancer.

Doctors often use hormone therapy to treat prostate cancer. This treatment usually works well for a few years. But the cancers often become resistant to hormone therapy at some stage. When this happens you may not have symptoms. But the levels of the PSA protein, made by your prostate cancer cells, will increase in your blood. This shows that your prostate cancer is becoming more active. Doctors may then use other treatments including steroids or chemotherapy. But these treatments often have unpleasant side effects.

Researchers are studying 2 drugs designed to treat other conditions, but which may help to stabilise or lower your PSA. These drugs do not have such severe side effects as steroids or chemotherapy. Pioglitazone treats diabetes, but is still safe if you are not diabetic. Fenofibrate treats high cholesterol. These drugs may make PSA levels stable or lower in some men. This suggests that their prostate cancer is being controlled. The aims of this study are to

See how these drugs affect PSA levels in men with symptom free hormone resistant prostate cancer
Find out more about the side effects
See how these drugs affect your quality of life

Recruitment

Start 01/05/2006

End 30/06/2014

Phase

Phase 2

Who can enter

You can enter this study if you

Have prostate cancer
Have had chemotherapy, or have been taking a combination of hormone therapies called pituitary down regulators and anti androgens, but this treatment is no longer working
Have rising PSA levels in your blood
Have satisfactory general blood tests
Are well enough to take part (performance status 0, 1 or 2)
Are over 16 years of age
Are willing to be monitored by the study team for 6 weeks before you start the study treatment

You cannot enter this study if you

Have symptoms from your prostate cancer that need urgent treatment (if you only have problems passing urine but do not have blood in your urine you may still be able to take part)
Have ever had a condition where your heart cannot pump blood quickly enough (heart failure)
Are taking medication to control your blood sugar levels
Are taking medication from a group of drugs called ‘fibrates’ to treat high cholesterol
Are taking the painkiller diclofenac (unless your doctor can give you another treatment instead, before you start the study)
Are taking medication as part of another clinical trial

Trial design

This study will recruit 50 patients. Everyone will take pioglitazone, with or without fenofibrate, depending on how their cancer responds to pioglitazone.

If you start to have symptoms from your prostate cancer at any time, you will leave the study. You then continue to see your regular cancer specialist.

At the start of the study, you will stop taking any anti androgen hormone therapy. Before you start the study treatment, the research team will monitor you for 6 weeks. This includes having a blood test every 2 weeks to measure your PSA level.

You then take pioglitazone tablets, once a day with food, for 6 weeks. If at 6 weeks your PSA level is stable or falling, you continue to take pioglitazone until your PSA starts to rise. If at 6 weeks your PSA starts to rise, you will also take fenofibrate tablets for a further 6 weeks. You take fenofibrate once a day with food.

After this, if your PSA is now stable or falling, you will continue this treatment. If your PSA starts to rise on pioglitazone and fenofibrate, you will also take a vitamin called calcitriol. You continue to take these 3 drugs until your PSA rises again. You then finish the study, and continue to see your regular cancer doctor in the same way as you did before.

Hospital visits

Before, during and after you finish the study, you will see the doctor, have some blood tests and complete a questionnaire. The questionnaire will ask about any side effects you have had and about how you have been feeling. This is called a quality of life study.

You will visit the hospital to see the research team and have a PSA test about every 2 weeks throughout the study. This will change to once a month if your cancer responds to pioglitazone. You will also fill out a questionnaire at these monthly visits.

After you finish the study, you will continue to visit the research team and have a PSA test each month for the rest of your life. You will also continue to see your regular cancer specialist in the same way as before the study.

Side effects

The side effects of pioglitazone include

Mild ankle swelling
Headache
Weight gain
Short term changes to the way your liver works
A condition where your heart cannot pump blood quickly enough (heart failure) – this is rare

The side effects of fenofibrate include