Supercharged T-cells – US approves new immunotherapy for cancer
“F.D.A approves second gene-altering treatment for cancer” reports the New York Times this week. But what treatment are they talking about and what does it do?
The treatment the Times refers to is called Yescarta, the second in a new type of immunotherapy to be approved by the Food & Drug Administration in the US. The treatment involves genetically altering cells of the patients’ immune system so that they turn on the cancer and attack it like they would an invading pathogen such as a virus or bacteria. This type of treatment is called CAR T-cell therapy and has been described as giving the patient a “living drug”.
In short, a sample of blood from the patient is drawn and white blood cells, called T-cells, are isolated from the rest of the blood in the lab. T-cells are the attack dogs of the immune system, recognising trespassers and eradicating them before they can do any damage. The patients T-cells are then genetically engineered so that they produce special molecules on their surface called CARs (hence the name CAR T-cell therapy). Now that the T-cells have CARs on their surface they are able to recognise tumour cells and attack them. The patients pumped-up T-cells are then allowed to replicate in the lab until there is an army of them ready to be transplanted back into the patient where they can get to work fighting cancer cells.
This type of personalised treatment comes at a great cost and Yescarta is predicted to cost around 373,000 US dollars per patient. There are also many risks associated with this type of therapy but as with the development of other drugs, further research will enable the therapy to be improved and made more effective.
What is Worldwide Cancer Research doing in this area?
We are currently funding Dr Gilbert Fruhwirth at King’s College London who is working on a new way to visualise CAR T-cells as they move around in a patient. The hope is that this will improve how CAR T-cell therapy is monitored after administration to a person to better understand how the treatment is working and also to ensure its safety.
Dr Fruhwhirth wants to insert an extra gene into CAR T-cells that makes them visible to clinical imaging methods such as a PET/CT scan. His team are testing this technology in mice to first see if they can track and monitor CAR T-cells in real-time. Dr Fruhwirth says that “If successful, we can start a new Phase I clinical trial to test this technology in humans.”