A trial looking at enzalutamide for men with prostate cancer that has spread (ENZAMET)

Please note - this trial is no longer recruiting patients. We hope to add results when they are available.

Cancer type:

Prostate cancer




Phase 3

This trial is looking at a type of hormone therapy called enzalutamide for newly diagnosed prostate cancer that has spread to another part of the body.

More about this trial

Prostate cancer depends on the male hormone testosterone for its growth. Doctors use different types of hormone therapy either to reduce the amount of testosterone Open a glossary item in the body, or by blocking it from reaching the cancer cells. This can shrink a prostate cancer or slow its growth.

Enzalutamide is a type of hormone therapy. It is currently used for men with prostate cancer that has spread when hormone therapy has stopped working and after having a type of chemotherapy called docetaxel.

In this trial, researchers are looking at giving enzalutamide compared with giving the usual hormone therapy. So some men in the trial have enzalutamide and some men have usual hormone therapy for prostate cancer that has spread. 

The aims of the trial are to

  • Find out if having enzalutamide works better than usual hormone therapy for men with newly diagnosed prostate cancer that has spread  
  • Learn more about the side effects

Who can enter

The following bullet points list the entry conditions for this trial. If you are unsure about any of these speak with your doctor or the trial team. They will be able to advise you. 

You may be able to join this trial if all of the following apply. You

  • Have had a previous tissue sample (biopsy Open a glossary item) taken from the area that your prostate cancer has spread to, or you have had a previous surgery or tissue sample taken from your prostate and you have prostate cancer which has spread, or you have prostate cancer which has spread to the bones or lymph nodes Open a glossary item and you have a PSA level Open a glossary item of 20 or more 
  • Are well enough to carry out all your normal activities, apart from heavy physical work (performance status 0 or 1). You may be able to take part if you are well enough to be up and about for at least half the day (performance status 2) but only if this because of your cancer spread
  • Have satisfactory blood test results 
  • Are willing to use reliable contraception if there is any chance your partner could become pregnant
  • Are at least 18 years old

You cannot join this trial if any of these apply. You

  • Have a large number of cells called sarcomatoid, spindle cell or neuroendocrine small cells in the tissue sample (biopsy) taken 
  • Have had hormone therapy for prostate cancer unless you started having it within 12 weeks of joining the trial and your PSA level is stable or falling. Or if you had it after surgery, you stopped having it more than a year ago and you didn’t have it for more than 2 years
  • Have had chemotherapy for prostate cancer unless you had only 2 cycles of docetaxel and you tolerated the full dose so far
  • Have any condition that means you could have fits (seizures) or if you have experienced any seizures in the past.
  • Have blacked out or had a mini stroke (TIA) in the last year
  • Have had a serious heart problem in the last 3 months such as a heart attack or a condition called congestive heart failure
  • Have had another cancer in the last 5 years apart from non melanoma skin cancer Open a glossary item or successfully treated early bladder cancer Open a glossary item
  • Have a problem with drugs or alcohol
  • Are having any other treatment as part of a clinical trial already
  • Have any other medical condition including a serious infection that the trial team think would affect you taking part in this trial

Trial design

This is a phase 3 trial. The researchers need 1,100 men worldwide to take part. It is a randomised trial. The men taking part are put into treatment groups by a computer. Neither you nor your doctor will decide which group you are in. 

  • One group have enzalutamide and hormone therapy injections
  • The other group have usual hormone therapy and hormone therapy injections

Diagram for ENZAMET

Enzalutamide is a capsule. If you are in the enzalutamide group you take 4 capsules once a day every day.

If you are in the usual treatment group, you have hormone therapy such as bicalutamide, nilutamide or flutamide. These are either tablets or capsules. How often you take them depends on the type you are having. Your doctor can tell you more about this. 

All the men taking part also have hormone therapy injections such as goserelin or leuprorelin unless they have had surgery to remove both testicles (an orchidectomy). You have this type of hormone therapy as injections under the skin or into a muscle every 3 months.

As long as you don’t have bad side effects, you can carry on having treatment for as long as your doctor thinks it is still helping you.

The trial team will ask you to fill out a questionnaire 

  • Before you start study treatment
  • 4 weeks after you start study treatment
  • Every 3 months during treatment 
  • When you stop study treatment
  • About a month after you finish study treatment

The questionnaire will ask about side effects and how you’ve been feeling. This is called a quality of life study Open a glossary item

You have the option to donate extra blood tests as part of this trial. Where possible you have these at the same time as your routine blood tests. You will need to be fasting for these extra blood tests. The researchers want to look for substances called biomarkers Open a glossary item to find out why treatment might work for some people and not for others. If you don’t want to donate these blood samples for research, you don’t have to. You can still take part in the trial.

The researchers will also ask if you want to donate a sample of your cancer that was removed and stored (archived) when you had surgery or a biopsy Open a glossary item. They will look for biomarkers and they may use it for other tests in the future. If you don’t want to donate these samples for research, you don’t have to. You can still take part in the trial.

Hospital visits

You see the doctor to have some tests before taking part in the trial. These include 

You go to hospital 4 weeks after you start treatment for a check up. After that you see the trial team

  • 2 months later 
  • And then every 3 months while you are having treatment

When you stop the study drug, you will have the tests you had at the beginning of the trial repeated. You see the trial team again about a month after you stop treatment.

After that, the trial team, will contact you every 12 weeks to check how you are and if you have started any new treatments for your prostate cancer. 

Side effects

The most common side effects of enzalutamide include

  • Feeling or being sick
  • Constipation or diarrhoea
  • Muscle or joint pain
  • Muscle weakness
  • Headache
  • Cold like symptoms
  • Tiredness (fatigue)
  • Swollen legs and feet (peripheral oedema)
  • Shortness of breath
  • Hot flushes
  • High blood pressure
  • Losing weight or putting on weight
  • A drop in red blood cells causing tiredness and light headedness
  • Loss of sex drive (libido) and erections (impotence)

We have more information on 

Recruitment start:

Recruitment end:

How to join a clinical trial

Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Chief Investigator

Professor Ray McDermot
Dr Simon Chowdhury

Supported by

​ANZUP (Australian New Zealand Urogenital Prostate Cancer Group)
Cancer Trials Ireland
Astellas Pharma
Experimental Cancer Medicine Centre (ECMC) 

Freephone 0808 800 4040

Last review date

CRUK internal database number:


Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Keith took part in a trial looking into hormone therapy

A picture of Keith

"Health wise I am feeling great. I am a big supporter of trials - it allows new treatments and drugs to be brought in.”

Last reviewed:

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