A trial of masitinib and sunitinib for gastrointestinal stromal tumours that have got worse despite having imatinib

Cancer type:

Soft tissue sarcoma




Phase 3

This trial is comparing 2 drugs called masitinib and sunitinib for a rare type of soft tissue sarcoma called gastrointestinal stromal tumour or GIST. The people taking part have a GIST that has spread to another part of their body or can’t be removed with surgery.

If a GIST can’t be removed with surgery, or has spread to another part of your body, you may have a drug called imatinib. It is a type of biological therapy called a tyrosine kinase inhibitor or TKI.

Imatinib stops signals that cancer cells use to divide and grow. But GISTs may get worse despite having imatinib. Researchers are looking for new treatments to help people in this situation.

In this trial they are looking at 2 other TKI drugs called sunitinib and masitinib. The aims of the trial are to compare the 2 drugs to

  • See which is better for GISTs that have got worse despite having imatinib
  • Learn more about the side effects

Who can enter

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

  • Have a gastrointestinal stromal tumour (GIST) that has spread to another part of your body or can’t be removed with surgery, and has got worse while having imatinib
  • Have a GIST with large amounts of a protein called CD117 (your doctor can advise you about this)
  • Have at least 1 area of cancer that can be seen and measured on a scan
  • Have stopped taking imatinib and recovered from any side effects
  • Are well enough to be up and about for at least half the day (performance status 0, 1 or 2)
  • Have satisfactory blood test results
  • Are at least 18 years old
  • Are willing to use reliable contraception during the trial and for 3 months afterwards if there is any chance you or your partner could become pregnant

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

  • Have sarcoma that has spread to your brain or spinal cord (your central nervous system)
  • Have had any other type of cancer in the last 5 years apart from carcinoma in situ of the cervix or basal cell skin cancer
  • Have had another experimental drug in the last 4 weeks
  • Had higher than the standard dose of imatinib (your doctor can advise you about this)
  • Weren’t able to take imatinib
  • Have already had sunitinib or a similar type of drug (apart from imatinib)
  • Are known to be very sensitive to either masitinib or sunitinib, or to anything they contain
  • Have high blood pressure that can’t be controlled with medication, or have certain heart problems (the trial team can advise you about this)
  • Have had problems with drug or alcohol addiction, or drink large amounts of alcohol, or have a mental health problem, and the trial team think that any of these things could affect your taking part
  • Are pregnant or breastfeeding

Trial design

This phase 3 trial will recruit more than 300 people. It is a randomised trial. The people taking part are put into treatment groups by a computer. Neither you nor your doctor will be able to decide which group you are in.

  • Group 1 have masitinib tablets twice a day, every day
  • Group 2 have sunitinib tablets once a day for 4 out of every 6 weeks

trial diagram

As long as you don’t have bad side effects, you can carry on having the trial treatment for as long as it is helping you.

The trial team will ask you to fill out a questionnaire before you start treatment, every 8 weeks for the first 6 months of treatment, every 3 months for the rest of the time you are having treatment and when you finish treatment. The questionnaire will ask about side effects and how you’ve been feeling.  This is called a quality of life study.

They will also give you a diary card to keep at home. In this, you write down when you take your tablets and whether you take any other medication.

Hospital visits

You see the trial team and have some tests before you start treatment. The tests include

  • Physical examination
  • Blood tests
  • Heart trace (ECG Open a glossary item)
  • CT scan (if you haven’t had one in the last 4 weeks)

The trial team need to get a sample of your sarcoma to look for changes to certain genes. They should be able to get a sample from the tissue that was removed when you had surgery or a biopsy Open a glossary item in the past. So it is unlikely that you will need to have a new biopsy.

You see the trial team once a month for the first 4 months, once more 2 months later and then once every 3 months after that.

You have a physical examination and blood tests at each visit. You have a CT scan every 8 weeks for the first 6 months of treatment and then every 3 months after that. You have an ECG every 3 months during the first year of treatment, every 6 months in the 2nd year and then once every 3 months after that.

When you finish treatment, the trial team may ask you to have another biopsy. But you don’t have to agree to this if you don’t want to. You can still take part in the trial.

If you are in the group taking masitinib and stop the treatment, you may start having sunitinib or another type of treatment. If you do this, the trial team will phone you every 3 months to see how you are. And if you start taking sunitinib at this point, they will ask you to have a more CT scans. These will be about every 3 months.

Side effects

As masitinib is a new drug, there may be side effects we don’t know about yet. In trials so far, the most common side effects have been

The most common side effects of sunitinib include

  • Tiredness (fatigue) and weakness
  • Feeling or being sick
  • Diarrhoea
  • Skin rash
  • Changes to the colour of your hair or skin
  • A drop in the number of white blood cells causing an increased risk of infection
  • High blood pressure
  • Loss of appetite
  • Sore mouth
  • Taste changes
  • Swollen legs
  • Constipation
  • Aching muscles
  • Dehydration
  • Urine infections



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 Larry Hayward

Supported by

AB Science
Experimental Cancer Medicine Centre (ECMC)

Questions about cancer? Contact our 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.

Wendy took part in a new trial studying the possible side effect of hearing loss

A picture of Wendy

"I was delighted to take part in a clinical trial as it has the potential to really help others in the future.”

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