Steps Forward for CAR T-Cell Therapy Treatments
CAR-T therapy is to be offered to a wider range of cancer patients in trials, following recent developments in the technology.
CAR-T therapy came to prominence in the early 2010s, when manufactured T-cells showed success in treating certain cancers. There were, however, incidences where the treatment failed to take or the patient suffered severe side effects. Recent trials may have taken steps in addressing these issues and widening the use of the treatment.
What Is CAR-T Therapy?
Chimeric antigen receptor T-cell therapy (CAR-T therapy) is a type of immunotherapy used to kill cancer cells. The therapy involves collecting T-cells (a type of white blood cell, important in immune response) from a patient's blood, and genetically altering the cells to produce chimeric antigen receptors. These receptors contain proteins that allow the T cells to identify and kill specific cancer cells. The CAR-T blood is then given to the patient intra-venously as a treatment for their cancer.
How Is it Being Used?
This type of immunotherapy had previously only been offered to a narrow group of patients, depending on their specific type of cancer. As part of a clinical trial run by UCLH, the NHS will now offer the therapy to a wider group of patients - including those diagnosed with B-cell non- Hodgkin's lymphoma and chronic lymphocytic leukaemia. Almost 19,000 people across the UK are affected by these two types of blood cancer each year. This extension to the clinical trial is expected to offer a further treatment option to more patients in the future.
Are there Any Drawbacks to CAR-T therapy?
There are potential side effects to this type of therapy, including cytokine release syndrome, where a patient's immune system becomes over-activated. In other cases, the genetically altered T-cells fail, and disappear into the patient's bloodstream. To address these two challenges, the trial will use a new type of CAR-T therapy, which reduces the risk of the immune system becoming over-activated, whilst increasing the probability of its effectiveness.
Other Advancements in the Space
In a separate but related trial on the use of CAR-T therapy, Great Ormand Street Hospital and UCL are utilising the technology in a novel way to facilitate the treatment of T-cell Leukaemia. The treatment involves the harvesting T-cells from healthy individuals and performing base editing to edit their DNA. This means that the modified T-cells have the following benefits:
- They aren't attacked by the patient's immune system.
- They don't attack other modified T-cells before the treatment can be administered.
- They are less likely to disrupt or be disrupted by some other cancer treatments.
- They are able to be edited so as to recognise cancerous cells.
This treatment is particularly revolutionary for patients who have a form of cancer affecting their T-cells, as under the traditional method, the patient's T-cells would be difficult if not impossible to collect.
Although both above examples are in trial stage, with full results yet to be announced, the signs are positive and provide another string to the bow for the treatment of blood cancers in the UK and beyond.