A study of PARP inhibitors for ovarian cancer (PAIRS)

Cancer type:

Ovarian cancer





This study is looking at tissue and blood samples to work out who benefits most from having a PARP inhibitor. 

The study is for women who have:

  • ovarian cancer
  • primary peritoneal cancer
  • fallopian tube cancer

These cancers are treated in the same way. So when we use the term ovarian cancer in this summary, we are referring to all 3.

More about this trial

PARP inhibitors are a type of targeted cancer drug Open a glossary item. They are a treatment for some women with ovarian cancer. Sometimes PARP inhibitors stop working. Doctors call this becoming resistant to treatment. Researchers are running this study to find out why this happens. To do this they are collecting blood and tissue samples. They plan to look at:

  • samples taken before starting a PARP inhibitor
  • samples after you finish having a PARP inhibitor 

The main aims of the trial are to:

  • analyse samples from people whose cancer got worse on a PARP inhibitor
  • look for biomarkers Open a glossary item to understand why PARP inhibitors work for some people and not others

Who can enter

The following bullet points are a summary of the entry conditions for this study. Talk to your doctor or the study team if you are unsure about any of these. They will be able to advise you. 

Please note, there are three groups in this study. Each group has specific entry conditions and we haven’t listed them all.

Who can take part

You may be able to join the study if all of the following apply. You:

  • have epithelial ovarian cancer, primary peritoneal cancer or fallopian tube cancer
  • have high grade Open a glossary item (fast growing) cancer
  • have a sample of tissue available from when you were first diagnosed with ovarian cancer
  • have had treatment with a PARP inhibitor or you are due to start having long term treatment with a PARP inhibitor
  • are at least 16 years old 

Who can’t take part

You cannot join this study if any of these apply. You:

  • have low grade serous ovarian cancer, grade 1 or grade 2 ovarian cancer, endometroid cancer, clear cell cancer or mucinous cancer
  • have borderline ovarian cancer
  • didn’t have a tissue sample taken to confirm your diagnosis
  • stopped taking a PARP inhibitor within 3 months of starting treatment because of bad side effects
  • have any medical condition or mental health problem that the trial team think could affect you taking part

As well as the above there are specific entry conditions for each treatment group. Speak to your doctor or research nurse if you want to find out more about the entry conditions for this trial.

Trial design

The study team need 260 people to join the study. 

There are 3 groups. You join:

  • cohort A if you are having a PARP inhibitor and your ovarian cancer hasn’t got worse
  • cohort B if your ovarian cancer got worse on a PARP inhibitor
  • cohort C if your ovarian cancer got worse on a PARP inhibitor and you already gave a tissue sample

Your doctor will tell you which group you are suitable to join. They check your medical notes for information on your past and present health, and for information about your cancer.

Blood and tissue samples for research
The team ask everyone for a sample of tissue from when they were first diagnosed.

In cohort A you give extra blood samples and you also give a tissue sample if your cancer gets worse.

In cohort B you give a tissue sample when you join the study. The team also collect extra blood samples.

In cohort C, you only give an extra blood sample as part of the study. 

Where possible you give the blood samples at the same time as your routine blood tests.

The team plan to use the samples to:

  • see if there are any gene changes Open a glossary item (mutations) in your cancer cells
  • look for biomarkers Open a glossary item to understand why PARP inhibitors work for some people and not others

Hospital visits

This study is a sample collection study. You shouldn’t have any extra hospital visits if you take part. Where possible the team try to organise to collect the samples when you have a routine hospital visit.

The appointment to collect the tissue sample might take up to 4 hours. The team can tell you more about this. 

For those who are having a PARP inhibitor you have regular check ups with your doctor. These happen once a month to begin with. These visits are part of your routine care.

Side effects

The side effects of giving a tissue sample (biopsy) Open a glossary item include:

  • bruising
  • pain
  • infection at the biopsy site

If you have the biopsy using a CT scan Open a glossary item, there is a small risk of an allergic reaction to the contrast dye Open a glossary item.

You might have some possible slight bleeding or bruising from the blood tests. 

We have more information about the side effects of PARP inhibitors



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

Dr Patricia Roxburgh

Supported by

Artios Pharma Limited
NHS Greater Glasgow and Clyde
Wellbeing of Women

If you have questions about the trial please contact our cancer information nurses

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.

Last reviewed:

Rate this page:

No votes yet
Thank you!
We've recently made some changes to the site, tell us what you think