A new cancer therapy that uses the body’s own immune system to target tumours has yielded “extraordinary results” on terminally ill patients, according to scientists in the United States.
Patients with advanced blood cancer who were predicted to have only two to five months to live were treated with an infusion of immune cells and ‘cancer-targeting molecules.’
The technique involves engineering a patient’s own immune cells to recognize and attack their tumours.
So-called ‘T-cells’ - immune cells that seek out and destroy abnormal or infected cells – are removed from a patients’ blood and genetically engineered to produce ‘receptor’ molecules known as ‘chimeric antigen receptors (CARS).
T-cells are a vital part of the immune system. They protect against viruses and help to prevent cancer. They have been called a “living drug” and are able to survive in our bodies our entire lives. CARS are proteins that enable T-cells to recognise a specific antigen on tumour cells.
The modified CAR T-cells are then laboratory-grown in their billions before being transfused into patients where they target the cancer by reducing the ability of tumour cells to mask themselves from the body’s own immune system.
In one study, 94 per cent of around 35 patients with acute lymphoblastic leukaemia (ALL) saw their symptoms completely vanish.
In two other experimental trials involving more than 40 patients with either non-Hodgkin’s lymphoma or chronic lymphocyte leukaemia, more than 80 per cent of patients responded positively to the treatment, and more than half experienced complete remission for up to 18 months.
Professor Stanley Riddell, from the Fred Hutchinson Cancer Research Centre in Seattle hailed the results as “extraordinary.” Speaking at the annual meeting for the American Association for the Advancement for Science (AAAS), Dr Riddell said:
“This is unprecedented in medicine, to be honest – to get response rates in this range in these very advanced patients.
“We have a long way to go. The response is not always durable. Some of these patients do relapse, we are cognisant of that. But the early data is unprecedented. This is potentially paradigm-shifting in terms of how we treat them. I think this is a significant breakthrough.”
Despite the promising response to the treatment, researchers have urged caution over early trial results, warning that T-cell therapy does not work for everyone and that some patients suffer severe side effects that are much greater than conventional leukaemia treatments such as chemotherapy and radiotherapy.
The improvements seen in patients who had been treated unsuccessfully with every other form of cancer treatment however, have been widely hailed as unprecedented.
While this breakthrough is incredibly exciting it is important to recognise that these trials have been on a limited scale and there is still a great deal of research needed before genetically engineered T-cells can be used as a long-term defence against not only blood cancers but other cancers as well.
Paul Sankey is a senior clinical negligence solicitor at Slater and Gordon Lawyers in London.
The Slater and Gordon clinical negligence team are widely experienced in handling claims related to delayed diagnosis and misdiagnosed cancer. For a free consultation call our medical negligence solicitors on freephone 0800 916 9049 or contact us online.