A study looking at a vaccination called TroVax in people with bowel cancer that has spread and cannot be removed with surgery (TaCTiCC)

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

Cancer type:

Bowel (colorectal) cancer





This study is looking at how a vaccine called TroVax affects the immune system in people who have bowel cancer that has spread to another part of the body (advanced bowel cancer).

More about this trial

Doctors can treat advanced bowel cancer with chemotherapy, but researchers are looking for ways to improve current standard treatments Open a glossary item.

If you have cancer, your immune system tries to attack and kill the cancer cells. Treatments such as TroVax may help the immune system to do this. But other cells in your body can stop your immune system attacking the cancer. Researchers want to find out if a drug called cyclophosphamide can help to get rid of cells that stop the immune system attacking cancer cells.

The main aim of this study is to see if there is a difference in how well your immune system responds to bowel cancer (the immune response Open a glossary item) when you have TroVax or cyclophosphamide, or both.

Please note – This pilot study is not large enough to show whether the vaccine works as a treatment, but it is possible that your cancer may get smaller.

Who can enter

You may be able to enter this trial if

  • You have bowel cancer that has spread to another part of your body and can’t be removed with surgery
  • Your cancer specialist has assessed your cancer in the last 4 weeks and could see that it had shrunk or stayed the same size
  • You are well enough to be up and about for at least half the day (performance status 0, 1 or 2) and any symptoms from your cancer are well controlled
  • You have satisfactory blood test results
  • You are at least 18 years old
  • You are willing to use reliable contraception if there is any chance you or your partner could become pregnant
  • You are willing to go to the Clinical Research Facility in Cardiff about 6 to 8 times over 15 weeks.

You cannot enter this trial if you

  • Have cancer that has spread to your brain
  • Have already had TroVax
  • Finished chemotherapy less than 2 weeks ago
  • Have had treatment for any other type of cancer in the last 5 years apart from non melanoma skin cancer or prostate cancer if it has been stable for at least 5 years
  • Have problems with your immune system (you are immunosupressed) or take drugs that damp down your immune system
  • Are allergic to eggs or to the drugs cyclophosphamide or neomycin
  • Have certain autoimmune diseases Open a glossary item (the trial team can advise you about this)
  • Have any other medical condition or mental health problem that could affect you taking part
  • Are pregnant or breastfeeding


Trial design

This pilot study will recruit about 54 people who are having treatment for advanced bowel cancer at the University Hospital of Wales or Velindre Hospital. It is a randomised trial. The people taking part are put into 1 of 4 groups by a computer. Neither you nor your doctor will be able to decide which group you are in. It is important that people in all groups attend hospital regularly to give blood samples.

After finishing chemotherapy, out of every 6 people on the trial,

  • 1 has no further treatment but the trial team will monitor them closely
  • 1 has cyclophosphamide tablets for 2 weeks
  • 2 have TroVax injections over 4 months
  • 2 have cyclophosphamide tablets followed by TroVax injections

The trial lasts for 4 months, but if the doctors think the treatment is helping you and you don’t have any bad side effects, you may be able to carry on having it for longer.

Hospital visits

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

  • Physical examination
  • Blood tests
  • CT scan

The number of hospital visits you have will depend on which treatment group you are in. Everybody taking part has a number of blood tests over a 4 month period and a CT scan after 3 months.

You have TroVax injections into a muscle and you must stay at the hospital for at least an hour afterwards. You take cyclophosphamide tablets at home. During the weeks you take the tablets, a member of the trial team will phone you a couple of times to see how you are and check if you are taking the tablets.

If you carry on having treatment for longer than 4 months, you will go to hospital as often as you need to, depending on which group you are in.

Side effects

The possible side effects of TroVax include

  • Mild tenderness, at the injection site or in lymph nodes Open a glossary item close by
  • Fever or chills that may come and go
  • Flu like symptoms

We have more information about the side effects of cyclophosphamide. But as the dose used in this study is very low, the researchers do not expect there to be many side effects from this drug.

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 Andrew Godkin

Supported by

Experimental Cancer Medicine Centre (ECMC)
Haematology Clinical Trials Unit University of Cardiff
NIHR Clinical Research Network: Cancer

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.

Alan took part in a clinical trial for bowel cancer patients

A picture of ALan

“I think it’s essential that people keep signing up to these type of trials to push research forward.”

Last reviewed:

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