Biological therapies for chronic myeloid leukaemia (CML)

Imatinib (Glivec) is the main treatment for chronic myeloid leukaemia. It is a type of biological treatment that blocks cancer cell growth. Doctors call this type of drug a tyrosine kinase inhibitor. It blocks a protein made by CML cells. Most people with CML have a gene mutation called the Philadelphia chromosome. The gene is called the bcr/abl gene. It carries the instructions for the body to make an abnormal protein (the bcr/abl protein). This protein signals to the body to make far too many white blood cells. Imatinib blocks this protein and stops the overproduction of white blood cells.

There is information about the side effects of imatinib in the cancer treatments section.

Some people have CML that doesn't respond to imatinib (Glivec). In other people, their CML becomes resistant to imatinib after a time. There are other biological therapies that your doctor may suggest. They are similar to imatinib. Two of these newer drugs are dasatinib and nilotinib. You may have these drugs if you cannot have imatinib because of side effects or because you have had imatinib but it is no longer working.

Some people who have CML develop resistance to biological therapies that target the bcr/abl protein. Doctors are looking at a new tyrosine kinase inhibitor called ponatinib that targets other kinases and variations of the bcr/abl mutation. So far the clinical trials have looked promising in people who have already had other treatments for CML.

The Scottish Medicines Consortium (SMC) have approved dasatinib and nilotinib for use in chronic phase CML on the NHS in Scotland. The SMC have also approved the use of nilotinib for the treatment of adult patients with newly diagnosed CML in the chronic phase. The National Institute for Health and Clinical Excellence (NICE), in August 2011, said that nilotinib should be available within the NHS in England and Wales when imatinib is either no longer working or the side effects are severe. It is only available as part of the patient access scheme which means the manufacturer reduces the price of the drug for the NHS. NICE did not recommend dasatinib for CML because they say it is not cost effective.

There is more information about dasatinib and nilotinib in the cancer drugs section. And there is more information on biological therapies on our page about CML research.

Interferon is a type of biological therapy that can work well for chronic phase CML. It is usually used if imatinib does not work or stops working after a while. About 1 in 5 people have such a good response that there are no longer any Philadelphia chromosome positive cells found in their bloodstream or bone marrow. This response can be long lasting, sometimes for more than 10 years. Experts recommend that you carry on with the interferon for at least 2 or 3 years after successful treatment because this will help to keep your leukaemia in remission for longer.

If you have had a bone marrow or stem cell transplant for CML, but your leukaemia comes back, your doctor may suggest treatment with interferon. This may be combined with more chemotherapy.

You have interferon alpha treatment as daily injections, just under the skin. You or someone you live with can learn to give them at home. But if you don't like the thought of that, your district nurse or practice nurse could do it instead.

Interferon does have side effects, but they vary a lot. Some people have very little trouble with interferon. Others find it very difficult to put up with. The most common side effects are a flu like reaction, with aching, a high temperature and weakness. Paracetamol usually helps. You may also feel sick and lose your appetite.

Some people have more severe side effects, with depression and mood changes. All side effects are likely to be more severe in older people. 

We have a section on biological therapies in CancerHelp UK, with detailed information about this treatment. There is information on the different types of biological therapies, including cancer growth blockers such as imatinib, and immunotherapies such as interferon. You can read more about the immune system elsewhere on this website.