Scientists have come up with a new way of treating leukaemia that may revolutionise the way the disease is managed from now on. Researchers have modified cells from people who suffer from leukaemia and changed them genetically so that they ‘attack’ the cancerous tumours within their bodies. This new treatment has proved to be so effective that tumours under this new treatment were ‘blown away’ in a matter of weeks with little side effects. Typically the treatment for leukaemia is managed with chemotherapy and can only be cured with a successful bone marrow transplant. The transplant however carries a risk of one in five mortality rate whilst only offering a 50/50 chance of survival.
The study, which took place at the University of Pennsylvania’s Abramson Cancer Centre in the United States, trialed three patients suffering from chronic lymphocytic leukaemia and took their T cells, the cells that are responsible for our immune system and fighting disease, and reprogrammed them. In most forms of cancer, it is these T cells that have lost their ability to recognise healthy cells from cancerous ones and therefore allow the cancer to spread unchecked. The study involved inserting a protein called a chimeric antigen receptor (CAR) which binds with another protein – called CD19 found in leukaemia tumour cells. The three patients tested were men in their 60s and 70s with a poor prognosis and had already tried seven or eight types of drugs. One year on they remain in a healthy condition.
And there is more to be hopeful for; as the T cells only target the damaged tissue, healthy skin and cells remain untouched and the side effects are a lot less unpleasant than typical chemotherapy. Plus they act as serial killer cells, multiplying rapidly themselves to destroy thousands of tumour cells. The modified T cells actually increased 1000 fold in each of the trialed patients whereas drugs do not have the capacity to do that. Dr David Porter, who co-authored the study, said: ‘Most of what I do is treat patients with no other options, with a very, very risky therapy with the intent to cure them. This approach has the potential to do the same thing, but in a safer manner. This massive killing of tumour is a direct proof of principle of the concept. Two British trials of this gene therapy are opening next year in London, one for acute myeloid leukaemia and the other for acute lymphoblastic leukaemia.