A trial of Sativex for persistent cancer pain (GWCA1103)

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 how much a drug called Sativex (nabiximols) helps people with cancer related pain that cannot be controlled with other strong painkillers.

It is quite common for people with advanced cancer Open a glossary item to have pain. There are different ways to treat cancer pain, including strong painkillers called opioids. But sometimes, even opioids cannot completely control 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. In this trial, Sativex is being compared with a dummy drug (placebo Open a glossary item). The aims of the trial are to

  • See which works best for cancer related pain that is not completely controlled with opioid drugs
  • Learn more about the side effects

Who can enter

You may be able to 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 that is not completely controlled with opioid painkillers and it is not possible to increase the dose of your painkillers any further – your doctor can advise you about this
  • Are willing to carry on taking your current painkillers throughout the trial
  • Are at least 18 years old
  • 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

You cannot enter this trial if you

  • Are going to have any treatment that could improve your cancer pain – including chemotherapy or radiotherapy
  • Are using more than 1 type of painkiller for breakthrough pain
  • Have had an experimental drug as part of another clinical trial in the last month
  • Have used cannabis (marijuana) or THC in the last month
  • Have had schizophrenia, or any other serious mental illness (or a close family member has)
  • 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 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 other heart problems
  • Have problems with your liver or kidneys
  • Have another 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
  • Have taken part in any other clinical trial of Sativex

Trial design

This trial will recruit about 540 people. It is in 2 parts.

You start by having Sativex as a mouth spray once a day. You gradually increase your dose until you find a dose that suits you. This can take up to 10 days. How often you end up using the spray depends on how much it helps to reduce your pain, and whether or not you have any side effects. The maximum dose you can have is 10 sprays a day.

If your pain reduces during this time, the trial team will ask you to join the 2nd part of the trial. This part is randomised. Neither you nor your doctor can decide which group you are in. And neither of you will know which group you are in. This is called a double blind trial.

  • Half the people taking part use the Sativex spray for 5 weeks
  • Half the people use a spray that doesn’t contain the drug (a placebo Open a glossary item)

At the end of the trial, 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 see the trial team and have some tests before you start the trial treatment. The tests include

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

There are 5 hospital visits all together. Each visit will last for about 2 hours, except for the 4th visit which will be a bit shorter.

During the trial, 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 that day. You will not be charged when you make these calls.

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 not to drink 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 11115

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Cara took part in a clinical trial

A picture of Cara

"I am glad that taking part in a trial might help others on their own cancer journey.”

Last reviewed:

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