Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.
A trial looking at natural killer cells after chemotherapy and radiotherapy for acute myeloid leukaemia
This trial was done to find out if having injections of natural killer (NK) cells from a healthy relative helps people with acute myeloid leukaemia (AML). And if it is a safe treatment.
Doctors usually treat AML with chemotherapy. After chemotherapy, there will be a lot of natural killer (NK) cells in your blood. We all have these cells in our blood, but there are more of them after chemotherapy. The NK cells are part of the
Doctors want to find ways of safely increasing the number of NK cells and make them better at killing resistant leukaemias. In this trial, they looked at using NK cells from a healthy relative. This is called an allogeneic donor cell infusion.
But some cells in the infusion called T lymphocytes could see your normal body cells as foreign and attack them. This is called graft versus host disease (GVHD). The researchers reduced the risk of GVHD by removing almost all the T lymphocytes. And they looked at a way of changing the NK cells so that they can kill resistant leukaemia cells, but don’t kill normal blood or bone marrow cells. These are called tumour activated NK cells (TaNKs).
The aim of the trial was to make sure that this type of treatment is safe, and to see
- Whether the donor TaNKs stay in the immune system
- If they can help to lower the risk of leukaemia coming back
Summary of results
The trial team found that the tumour activated natural killer cells (TaNKs) helped this small group of people with AML. It was safe to give and didn’t cause graft versus host disease.
Treatment to get rid of leukaemia cells is called induction treatment. Everybody taking part had induction treatment with standard chemotherapy. And then just before they had the TaNK cells, everybody had another chemotherapy drug called fludarabine and a single dose of
This small trial recruited 13 people. But 6 people couldn’t have the tumour activated NK cells (TaNKs). Either the induction treatment didn’t get rid of enough of their leukaemia cells, or they couldn’t find a healthy relative to take part. So 7 people went on to have TaNK cells.
The researchers looked at the results after 6 months to see how well the TaNK cells had worked. They had the results for 7 people and found that
- 3 people who had no signs of leukaemia (complete
remission) after induction treatment remained in complete remission after having TaNK cells
- 1 person whose leukemia had got a bit better (partial remission) after induction treatment went into complete remission after having the TaNK cells
- The leukaemia had come back in 2 people who had been in remission at the time of TaNK treatment
- Unfortunately the leukaemia came back in 1 person who died
When the researchers looked at the results again a year after treatment, they found that 1 person remained in complete remission. The leukaemia had come back in the other 3.
The trial team also looked at how long people lived after treatment. They found that this was just over a year on average.
Chemotherapy for leukaemia does have side effects, but there were no extra side effects from having the TaNK cells.
The trial team concluded that TaNK cells were safe to use for AML, and that they helped the immune system to get rid of leukaemia cells without causing graft versus host disease.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
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.
Dr Panagiotis Kottaridis
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer
Royal Free London NHS Foundation Trust
University College London (UCL)