A trial of Sativex for cancer related pain (GWCA0958)

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

Cancer type:

All cancer types




Phase 3

This trial is looking at Sativex for cancer pain that cannot be controlled with other strong painkillers. It is very similar to the GWCA0962 trial that is also listed on the database.

It is quite common for people with advanced cancer to have pain. Advanced cancer means the cancer has spread or come back since it was first treated.

There are different ways to treat cancer pain, including strong painkillers called opioids. But sometimes, even opioids cannot completely control the pain. Researchers are looking for ways to help people in this situation.

In this trial, they are looking at a drug called Sativex. The main active ingredients of Sativex are tetrahydrocannabinol (THC) and cannabidiol (CBD). Both of these molecules come from the cannabis (marijuana) plant.

In the UK, Sativex is already used to relieve symptoms of a disease called multiple sclerosis. It can also work as a painkiller. The aims of this trial are to

  • See if Sativex can help to relieve cancer related pain that is not completely controlled with opioid drugs
  • Learn more about the side effects

Who can enter

You can enter this trial if you

  • Have advanced cancer Open a glossary item and your doctors don’t think there is any treatment that would cure your cancer
  • Have pain related to the cancer and this is not completely controlled with appropriate doses of opioid painkillers
  • Have satisfactory blood test results
  • Are willing to use a reliable form of contraception during the trial and for 3 months afterwards if there is any chance you or your partner could become pregnant
  • Are at least 18 years old

You cannot enter this trial if you

  • Or a close family member have had schizophrenia, or any other serious mental illness
  • Have ever been dependent on drugs or alcohol, or currently drink large amounts of alcohol (the trial doctors can advise you more about this)
  • Have used cannabis or THC in the last month (the trial team will test your urine to check this)
  • Have epilepsy that is not well controlled, or you have had a fit (seizure) in the last year
  • Have had a heart attack in the last year, or have a heart condition or other serious medical condition that the trial doctors think would make it unsafe for you to join this trial
  • Are sensitive to any of the ingredients of Sativex
  • Are pregnant, breastfeeding, or planning to become pregnant in the next 3 months
  • Plan to travel outside the UK during the study

Trial design

This international trial will recruit about 380 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. And neither of you will know which group you are in either. This is called a double blind trial.

Everybody taking part will continue to take any painkillers that have already been prescribed for them. You do not need to stop taking other medication if you join this trial.

Half the people taking part have Sativex as a mouth spray. The other half have a mouth spray that contains a dummy drug (placebo Open a glossary item).

You start by using the mouth spray once a day, and gradually increase your dose until you find a dose that suits you. The maximum dose you can take is 10 sprays a day. You have treatment for 5 weeks.

During the 5 weeks of treatment, you have a phone number to call each day and record how bad your pain is, whether your sleep has been disturbed and what painkillers you have taken. You will not be charged when you make these calls.

At the end of the 5 week treatment period, the trial team may ask you if you want to join another trial for 6 months. This is called an extension trial. Everybody taking part in the extension trial will have Sativex.

Hospital visits

You will see the doctors and have some tests before you start having the study treatment. The tests include

  • Physical examination
  • Blood and urine tests
  • Heart trace (ECG Open a glossary item)

You go to see the trial team 4 times during the study. Each visit takes about 2 hours, but the 3rd visit may be a bit shorter. Between the 1st and 2nd visits, the researchers will measure how much pain you have and how well it is controlled with your current painkillers. They will then work out if it is appropriate for you to continue in the trial. You don’t start using the mouth spray until after the 2nd hospital visit.

2 weeks after the 4th hospital visit, a member of the trial team will contact you by phone to see how you are.

Side effects

There may be some side effects of Sativex that we don’t know about yet. The most common known side effects include

  • Feeling dizzy
  • Tiredness
  • Feeling sick

The trial doctors will advise you not to drive or use machinery until you know that the study drug is not affecting your ability to do these things. And they will advise you to avoid alcohol during the study, or to drink only small amounts, as it can interact with Sativex and make the effect much stronger.

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

Professor Marie Fallon

Supported by

GW Pharma
NIHR Clinical Research Network: Cancer

Questions about cancer? Contact our information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:

Oracle - 699

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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