A trial comparing olaparib with enzalutamide or abiraterone for men with prostate cancer (PROfound)

Cancer type:

Prostate cancer

Secondary cancers

Status:

Results

Phase:

Phase 3

This trial compared olaparib with enzalutamide or abiraterone for men with prostate cancer that had spread to other parts of the body.

It was for men who’d:

had surgery to remove the testicles (orchidectomy) or were having treatment with hormone therapy
had changes in genes called homologous recombination repair (HRR)

This trial was open for people to join between May and September 2018. The results were published in a journal in 2020 and on the pharmacy company’s website in 2021.

More about this trial

Prostate cancer needs the male sex hormone testosterone to grow. The testicles make testosterone. So, for prostate cancer that has spread (advanced prostate cancer) you might have:

surgery to remove the testicles (orchidectomy)
hormone therapy to reduce the level of testosterone in your body

But after some time, treatment can stop working and prostate cancer might start to grow again. Doctors call this castration resistant prostate cancer.

You usually have hormone therapy such as enzalutamide and abiraterone for castration resistant prostate cancer. But doctors are looking for new ways to help men in this situation. In this trial, they looked at olaparib.

This trial was in 2 parts. First, doctors tested a sample of your cancer for changes (mutations Open a glossary item

) in the HRR genes. You went on to the 2nd part of this trial if they found certain gene changes.

Everyone joining the 2nd part of this trial had one of the following:

olaparib (Lynprza)
enzalutamide or abiraterone

Olaparib is a targeted drug Open a glossary item

called a PARP inhibitor Open a glossary item

. It blocks an enzyme Open a glossary item

that cancer cells need to repair themselves and grow. At the time of this trial olaparib was already used as a treatment for women with ovarian cancer. Doctors thought it might help men with prostate cancer.

Enzalutamide and abiraterone are 2 types of hormone therapy Open a glossary item

. Both stop your body from making the hormone testosterone. At the time of this trial they were a common treatment for men with prostate cancer.

The main aim of this trial was to find out whether olaparib was better than enzalutamide and abiraterone for men with castration resistant prostate cancer.

Summary of results

The team found that men with advanced prostate cancer who had olaparib lived longer before their cancer got worse.

About this trial
This was a phase 3 trial. It was a randomised trial Open a glossary item . The people who took part were in 2 groups. Neither they nor their doctor chose which group they were in.

Of the 387 people who took part:

245 had olaparib
142 had either abiraterone or enzalutamide

profound_1.png

Results
The team looked at how long it took for the cancer to get worse. They found that the median Open a glossary item time it took was:

just under 7½ months (7.4 months) for those who had olaparib
just over 3½ months (3.6 months) for those who had enzalutamide or abiraterone

profound_2.png

They also looked at the how long people lived after treatment. They found that the median time was:

17½ months for those who had olaparib
just over 14 months (14.3 Months) for those who had enzalutamide or abiraterone

profound_3.png

Quality of life
After a year of treatment the team looked at pain. They wanted to know the number of people whose pain had not got worse. They found it was:

about 76 people out of every 100 (76½%) for those who had olaparib
about 43 people out of every 100 (43.1%) for those who had enzalutamide or abiraterone

Side effects
There were more severe side effects with olaparib than with either enzalutamide or abiraterone.

The most common side effects overall for olaparib were:

a drop in blood cells causing tiredness, increase of infection, bruising and bleeding
feeling or being sick
tiredness and lack of energy (fatigue)
feeling weak
loss of appetite
changes in taste
diarrhoea or constipation
indigestion and heartburn
inflammation of the mouth and lips
loss of weight
breathlessness
swelling of the arms and legs

The most common side effects overall for enzalutamide or abiraterone were:

tiredness (fatigue)
lack of energy
feeling weak

Conclusion
The trial team concluded that olaparib worked better than enzalutamide or abiraterone for men:

with prostate spread that had continued to grow despite hormone treatment
and had changes (mutations) in the HRR genes

When compared with enzalutamide and abiraterone, olaparib:

stopped the cancer getting worse for a longer time
was better for and more accepted by the patients

Researchers are looking at olaparib in further trials.

Where this information comes from
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item ) and published in a medical journal. The figures we quote above were provided by the trial team who did the research. We have not analysed the data ourselves.