A trial looking at pembrolizumab for people with advanced gynaecological cancer (PEACOCC)

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

Cancer type:

Cervical cancer
Ovarian cancer
Secondary cancers
Vaginal cancer
Vulval cancer
Womb (uterine or endometrial) cancer




Phase 2
This trial is for people with gynaecological cancer that has come back or spread to other parts of the body (advanced cancer). Gynaecological cancers include:
  • ovarian cancer (which also includes primary peritoneal cancer and fallopian tube cancer)
  • womb (endometrial or uterine) cancer 
  • cervical cancer
  • vaginal cancer 
  • vulval cancer
It is for people who have a rare type of gynaecological cancer called clear cell cancer. 

More about this trial

Surgery and chemotherapy are common treatments for women with gynaecological cancer. Chemotherapy can work for some time, but the cancer can come back or spread to other parts of the body. This is sometimes referred to as advanced cancer. 

Doctors are looking for new ways to help people in this situation. In this trial, they are looking at pembrolizumab. 

Pembrolizumab (Keytruda) is a type of targeted drug called a monoclonal antibody. It targets and blocks a protein called PD-1 on the surface of certain immune cells called T-cells. Blocking PD-1 triggers the immune system cells to find and kill cancer cells. 

The main aim of this trial is to find out how well pembrolizumab works as a treatment for advanced clear cell gynaecological cancer.

Who can enter

The following bullet points list the entry conditions for this trial. Talk to your doctor or the trial team if you are unsure about any of these. They will be able to advise you. 
Who can take part
You may be able to join this trial if all of the following apply:
  • you have clear cell cancer of the ovaries (including primary peritoneal and fallopian tube), womb, cervix, vagina or vulva
  • you have at least 1 area of cancer that can be seen and measured on a scan 
  • your cancer has got worse (progressed) 
  • you have had chemotherapy 
  • you are willing to give a sample of tissue (biopsy) and new samples for the trial team to do some tests on
  • you have satisfactory blood tests results 
  • you are willing to use reliable contraception during treatment and for up to 4 months afterwards if there is any possibility that you could become pregnant
  • you are at least 18 years old 
  • you are well enough to carry out your normal activities apart from heavy physical work (performance status of 0 or 1)
Who can’t take part
You cannot join this trial if any of these apply. 
Cancer related
  • have had a targeted cancer drug or chemotherapy within 4 weeks of the planned start date of the trial treatment and still have moderate or severe side effects from it, apart from hair loss and tingling or numbness in fingers and toes 
  • have had radiotherapy in the last 2 weeks 
  • have had pembrolizumab or any other similar drug 
  • you have cancer spread in your brain, spinal cord or the membranes surrounding the brain (carcinomatous meningitis)
  • have another cancer that is getting worse or needs treatment
Medical conditions
You cannot join this trial if any of these apply. You:
  • are taking part in another clinical trial or have taken part in a trial looking at a new drug or device in the last month 
  • have an autoimmune disease that needed treatment that reached your whole body (systemic) in the past 2 years unless it was treatment to replace something that the body makes such as thyroxine or insulin 
  • have or have had lung problems such as pneumonitis
  • have a blood clot in your lungs (pulmonary embolism) or in a deep vein of your body (deep venous thrombosis) unless you have had treatment for it in the past 2 weeks 
  • have had a blood clot in a blood vessel that carries blood from the heart to the rest of your body (artery) in the last year
  • have an active infection that needs antibiotics that reach your whole body (systemic) 
  • have had a blockage in your bowel (bowel obstruction) in the last month
  • have an abnormal opening (fistula) in your tummy (abdomen) 
  • take or have taken drugs that damp down your immune system such as steroids in the past week unless it was a very small dose 
  • have active tuberculosis 
  • have HIV 
  • have hepatitis B or active hepatitis C 
  • have any other serious medical condition or mental health problem that the trial team think could affect you taking part 
  • take an amount of alcohol or drugs that are a concern for your doctor 
You cannot join this trial if any of these apply. You:
  • are pregnant or breastfeeding  
  • are sensitive to pembrolizumab or anything it contains 
  • have had a live vaccine in the last month 

Trial design

This is a phase 2 trial. Researchers hope that around 48 people from the UK will agree to take part. 
You have pembrolizumab as a drip into your bloodstream (intravenously) every 3 weeks. It takes up to 30 minutes to have each pembrolizumab treatment. 
You continue to have pembrolizumab for as long as it is helping you and the side effects aren’t too bad. You can have up to 35 treatments taking about 2 years in total. 
You have regular tests to check how well the treatment is working. You might stop pembrolizumab if tests show that your cancer has disappeared. But if your cancer comes back again after this, you may be able to start a second course of pembrolizumab. Your doctor can tell you more about this.
Quality of life
Everybody taking part completes quality of life questionnaires before the start of treatment and:
  • at set times during the trial
  • a month after finishing treatment 
  • then every 3 months if your cancer doesn’t get worse  
The questionnaires ask about how you have been feeling and what side effects you have had. 
Blood tests 
You have extra blood tests as part of this trial. You have them before the start of treatment and then:
  • at set times during the trial
  • a month after finishing treatment 
Researchers want to look for certain proteins (biomarkers) that can help to tell how well the treatment is working. 
Tissue sample
You need to have tissue samples taken (biopsy):
  • before the start of this trial 
  • 6 to 8 weeks after the start of treatment 
  • if your cancer gets worse

The team ask permission to keep and test a stored sample of cancer tissue. You might have given this sample when you were first diagnosed or when you had any surgery for your cancer.

Hospital visits

You see a doctor and have some tests before taking part. These tests might include: 
  • a physical examination 
  • blood tests
  • urine test
  • MRI scan and a CT scan of your chest 
During treatment you see the trial team every 3 weeks. You have blood tests and a physical examination every time you see them. 
You have scans every 6 weeks, for 3 months. You then have scans every 12 weeks. This continues for as long as your cancer doesn’t get worse and the side effects aren’t too bad. 
When you finish treatment, you see the trial team after a month. You then see or speak with the trial team every 3 months as needed. 

Side effects

The trial team monitor you during treatment and afterwards. You have a phone number to call them if you are worried about anything. The team will tell you about all the possible side effects before you start the treatment. 
Pembrolizumab can affect the immune system. It may cause inflammation in different parts of the body which can cause serious side effects. They could happen during treatment, or some months after treatment has finished. Rarely, these side effects could be life threatening.

If you have any of these side effects, you should tell the doctor or nurse as soon as possible. You should tell them that you are on or have been on an immunotherapy. 

The most common side effects of pembrolizumab are:

• cough 
• loose or watery poo (diarrhoea)
• tiredness (fatigue)
We have more information about the possible side effects of pembrolizumab

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 Rebecca Kristeleit

Supported by

University College London (UCL)
Merck, Sharp & Dohme
Cancer Research UK & UCL Cancer Trials Centre
National Institute for Health Research (NIHR)
Queen Mary University of London (Barts Gynae Tissue Bank)


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.

Over 60,000 cancer patients enrolled on clinical trials in the UK last year.

Last reviewed:

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