Research into childhood acute lymphoblastic leukaemia (ALL)
Researchers are looking into new treatments for acute lymphoblastic leukaemia as well as ways to reduce the side effects treatment can cause.
There are a number of clinical trials for children to join in the UK. And many children and young people with childhood leukaemia have their treatment as part of a clinical trial.
Individual trials close when enough people have joined. There might then be a period of time before the results are available. New trials then open based on the lessons learned. Because of research, treatment for childhood ALL has got much better over the past 30 years. Now, more than 9 out of 10 children (more than 90%) with ALL survive.
This video shows how Cancer Research UK is involved in researching childhood leukaemia.
Inside our bones is bone marrow and it’s where blood cells are formed from special cells called stem cells. Normally, these ‘blood factories’ pump out immature cells, which then mature into fully fledged red blood cells, white blood cells or platelets.
In acute leukaemia however, a fault occurs in these stem cells before we’re born, which means that the immature cells get stuck and never continue their journey to becoming useful cell types. This blockage in the system prevents the stem cells from doing their job.
Soon, this build up of problem cells spills out of the bone marrow and into the bloodstream, causing tumours to form in other parts of the body.
So, what causes the stem cells to produce these cancerous little blighters in the first place?
In most infant leukaemia, a translocation is responsible for the fault. This is when a section of one chromosome is switched with a section from another.
This change to the body’s chromosomes causes leukaemia but we don’t yet know exactly how it occurs.
Katrin Ottersbach, at the University of Edinburgh, is developing a way to study what happens, spot any markers of leukaemia earlier and crucially, allow us to test potential new treatments.
Across the country, Cancer Research UK is funding work like this, to better understand cancers affecting children and young people and to develop new, better and kinder treatments.
ALLTogether1
ALLTogether1 is a clinical trial developed on what we have learned from previous ALL research such as UKALL 2011. This trial is for those newly diagnosed with ALL from the ages of 1 to 45 years old (up to age 29 in the UK). It’s a large trial that includes several European countries. The overall aim is to improve survival and the quality of survival for children and young adults with ALL.
UKALL 2011
This was the largest clinical trial looking at ALL treatment in the UK. Doctors treat childhood ALL with chemotherapy. They use a number of drugs in different combinations. As with all treatments, there are side effects and doctors are always looking for ways to reduce them.
Researchers on this trial wanted to see if by changing the standard treatment they can reduce the side effects of current leukaemia treatment. And if they can reduce the chance of leukaemia coming back after treatment.
This trial has now closed and we are awaiting the results. You can find out in more detail about the trial and the results by clicking on the below link.
Research into ALL that has come back or not gone away with treatment
ALL that has not gone away with treatment (refractory) or has come back after treatment (relapsed) is harder to treat.
Researchers are looking at a
Dexamethasone is the steroid that is already a treatment for leukaemia. Selumetinib works by blocking signals that allow the cancer to continue to grow. The researchers are hoping this might help stop or slow down the growth of the leukaemia cells.
Another type of targeted cancer drug being looked at is a
- it can improve treatment outcomes
- people can cope having both treatments together
Researchers are also looking at a drug called pegylated recombinant human arginase (BCT-100) to help this group of children. Arginine is a protein (an amino acid) that’s important for cells to grow and survive. Normal, healthy cells can make arginine using a protein (an enzyme) that is often missing in cancer cells. If the amount of arginine available is reduced, it starves the cancer cells and stops them from growing.
Healthy cells are able to survive much better than cancer cells when there is less arginine available. This is partly because they can make it. So, by reducing the amount of arginine available the cancer might stop growing. They hope by giving this drug it will lower the amount of arginine available and stop the cancer from growing.
Immunotherapy using CAR T-cells
White blood cells called lymphocytes play an important part in fighting infection and diseases, including cancer. There are different types of lymphocytes. T cells are one type.
T cells move around the body to find and destroy defective cells. When you come into contact with a new infection or disease, the body makes T cells to fight that specific infection or disease. It then keeps some in reserve so that if you come across the infection again your body can recognise it and attack it immediately.
T cells are good at fighting infection. But it can be difficult for them to tell the difference between a cancer cell and a normal cell. So, the cancer cells can hide away and not be recognised.
Scientists are trying to find ways to get T cells to recognise cancer cells. One possible way to do this might be CAR T-cell therapy.
CAR T-cell therapy is a very specialised treatment. A specialist team takes a sample of T cells from your child’s blood or a donor. This process is called apheresis.
In the laboratory the T cells are changed. You might hear this called genetically engineering the T cell. The T cell is now a CAR T-cell. CAR stands for chimeric antigen receptor. These CAR T-cells are designed to recognise and target specific proteins on the cancer cells.
These changed T cells grow and multiply in the laboratory. Once there are enough cells your child has a drip containing these cells back into their bloodstream. The aim is for the CAR T-cells to then recognise and attack the leukaemia cells.
Researchers are looking at CAR T-cell therapy in clinical trials for children and young people with leukaemia and lymphoma. Following guidance in 2018, CAR T-cell therapy is now used as a treatment for some children with a type of leukaemia called B cell ALL.
Research into longer term side effects
Researchers are also looking into the long term effects of treatment for all types of childhood cancer. The Centre for Childhood Survivor Studies is carrying out the British Childhood Cancer Survivor study.
This research is looking at children who were diagnosed with cancer between 1940 and 1991 and lived for at least 5 years after diagnosis.
This type of research takes many years to produce results because the children need to be followed throughout their lives. So, it will be some time before we know the results.
How to join a clinical trial
The best person to speak to about your child joining a clinical trial is their hospital consultant.
There might also be a research nurse at their primary treatment centre you can talk to. You could always chat through the options with your child’s clinical nurse specialist. They are able to answer or find out an answer for, any specific questions you or your child might have.
You can find more information about clinical trials into treating acute lymphoblastic leukaemia on our clinical trials database.