We must fully research all potential treatments before we can adopt them as standard treatment for everyone. This is so that:
- we can be sure they work
- we can be sure they work better than the treatments that are available at the moment
- they are known to be safe
Thanks to research the 10 year survival for leukaemia has more than quadrupled in the last 40 years. But researchers continue to look for new and kinder treatments to further improve survival and quality of life. They also want to learn more about how blood cancers such as ALL develop, and what the genetic differences are between leukaemia cells in adults and children, and how this might affect treatment decisions in the future.
If you are interested in open UK clinical trials for ALL, go to:
Chemotherapy uses anti cancer (cytotoxic) drugs to destroy cancer cells. The drugs circulate throughout the body in the bloodstream. It is the main treatment for ALL.
Trials are looking into:
- different combinations of chemotherapy drugs
- reducing chemotherapy side effects
- new chemotherapy drugs such as nelarabine
- how chemotherapy affects quality of life
- chemotherapy for different age groups
Resistance to chemotherapy
One difficulty in treating leukaemia with chemotherapy is that it might gradually become resistant to the chemotherapy. In other words, treatment that worked before no longer does. This is because the cells of many cancers have an overactive gene called mdr1. This stands for multi drug resistance.
Cells that have this overactive gene create a protein that makes the cancer cell pump out any chemotherapy drug that gets inside. Some new drugs have been tried that can overturn this, but they cause a lot of side effects. More research is needed to find better ways to use these drugs.
Stem cell and bone marrow transplants
Stem cell and bone marrow transplants for ALL use high dose chemotherapy, and sometimes total body irradiation (TBI) and targeted cancer drugs. This treatment kills off all the stem cells inside your bone marrow that make your blood cells. To replace these you usually have someone else's (a donor's) stem cells or bone marrow.
This high dose treatment can cause severe side effects. Doctors are trying to find ways of improving treatment to reduce these side effects.
Half matched transplants
Doctors can't find a stem cell match for about 1 in 3 people who need a transplant. So for these people an option might be to have a half matched or haploidentical stem cell transplant. This transplant uses donor stem cells from a family member who is at least a 50% match. Researchers are looking at a better way to give and reduce the side effects for this type of transplant.
Stem cells from umbilical cords
Doctors sometimes use blood stem cells collected from the umbilical cords of newborn babies. In trials they are looking to see if they can use these stem cells with different doses of chemotherapy and what the side effects are.
Helping with recovery after a transplant
Other researchers are looking at improving a person’s immune system once they have had a stem cell transplant from an unrelated donor. The immune system, which normally protects the body from infection, doesn’t work properly for several months after a transplant.
Researchers are looking at a way of giving donor immune cells (T cells) after a transplant to help fight infection. They hope this will help people recover more quickly but without increasing the risk of getting graft versus host disease (GvHD).
GvHD is a complication of donor transplants, where the donor’s T cells fight the body’s own tissues, causing problems such as diarrhoea, skin rashes or liver damage.
Targeted cancer drugs and immunotherapy
Targeted cancer drugs change the way that cells work, for example, they can block signals that tell cells to grow. There are different types of targeted cancer drugs including monoclonal antibodies and tyrosine kinase inhibitors.
Immunotherapies can boost the body's own immune system to fight off or kill cancer cells.
Monoclonal antibodies can seek out cancer cells by looking for particular proteins on the cell’s surface. Some of the drugs currently being looked at in people with ALL are:
- inotuzumab ozogamicin (INO)
- moxetumomab pasudodotox
- denintuzumab (SGB-CD19A)
Cancer growth blockers
Tyrosine kinase inhibitors
Tyrosine kinases are chemicals that cells use to signal to each other. Some of these signalling systems tell cancer cells to grow and divide. Scientists have been working on drugs called tyrosine kinase inhibitors (TKIs) that block these signals.
Imatinib (Glivec) is a TKI. It is a treatment for people with ALL who have a particular chromosome change called the Philadelphia chromosome. About 20 to 30 out of every 100 people with ALL (about 20 to 30%) have this change. Research studies show that having imatinib as part of your first phase of treatment (remission induction therapy) improves your chances of getting into remission.
Other TKI's that are being looked at in trials include:
Proteasomes are tiny, barrel shaped structures found in all cells. They help break down proteins the cell doesn't need into smaller parts. The cell can then use them to make new proteins that it does need.
Drug treatments that block proteasomes from working are called proteasome inhibitors. They cause a build up of unwanted proteins in the cell, which makes the cancer cells die.
Researchers are looking at some of these drugs in clinical trials for ALL:
CAR T-cell therapy (chimeric antigen receptor T-cell therapy) is a very new type of immunotherapy treatment. It is being looked at in early phase trials and uses your own immune system to treat leukaemia.
Researchers remove a certain type of white blood cell, called T cells. These cells are very good at helping fight infections but they aren't so good at telling the difference between a normal cell and a cancer cell. The researchers change the T cells in the laboratory and give them back to you through an infusion. The researchers hope the altered T cells will recognise and attack any leukaemia cells.