This is an international
phase 3 trial. Researchers need around 340 men with changes in the homologous recombination repair (HRR) gene to take part.
This trial is in 2 parts:
- part 1 is the screening
- part 2 is the treatment
Part 1 (screening)
Everyone gives a sample of tissue (archival tumour sample) to check for changes in the HRR genes. You need to have a biopsy if there isn’t a suitable sample available.
The trial doctor will tell you the results of the test when they are available. It usually takes around 2 weeks. You then:
- stop the trial if you don’t have changes in the HRR gene
- have more tests such as blood tests and scans to find out whether you can join the 2nd part of this trial if you have changes in the HRR gene
Your doctor will tell you which other treatments you might have if you can’t join the 2nd part of this trial.
Part 2 (treatment)
This part of the trial is
randomised. Everyone is put into 1 of the following treatment groups by a computer:
- olaparib
- enzalutamide or abiraterone
Neither you nor your doctor will be able to decide which group you are in. And you are 2 times more likely to have olaparib than enzalutamide or abiraterone.
You have olaparib as tablets or capsules that you swallow whole, twice a day. You should wait at least 2 hours after eating before taking them. And after you have taken them, don’t eat for an hour afterwards.
You have enzalutamide or abiraterone as tablets that you swallow whole, every day. Your doctor can tell you which treatment you will have.
You continue to take olaparib, enzalutamide or abiraterone for as long as it helps you and the side effects aren’t too bad.
You may be able to cross over to the olaparib group if your cancer gets worse after treatment with enzalutamide or abiraterone. Your doctor can tell you more about this.
Quality of life
- at set times during the trial
- after you finish treatment
The questionnaires ask about how you have been feeling and what side effects you have had.
Blood tests
You have some extra blood tests as part of this trial. Researchers want to:
- find out what happens to olaparib in your body
- look for substances called biomarkers
to see why treatments work better for some people than others
- find out whether you have inherited changes in the HRR gene
You have the extra blood tests before the start of treatment and at set times during the trial.
Doctors may also ask you to have a blood test to look at your
DNA 
. You don’t have to agree to this if you don’t want to. You can still take part in this trial.