An international team of scientists has reported important results using patients' own immune cells to fight cancer. In one trial, symptoms disappeared in 94% of patients with acute lymphoblastic leukaemia. In other types of blood cancer, response rates over 80% have been reported, and over half experienced complete remission.
The T-cell treatment used is an immunotherapy using the patient's own T cells, which are reprogramming in vitro to attack tumours. Scientists have been working on immunotherapy for decades, but only recently has the focus moved to T-cell therapy in humans. The current research is experimental in nature and thus trials have been limited to patients no longer responding to other treatments. The results are currently undergoing peer-review prior to possible publication.
The normal immune response is often not quick or aggressive enough to combat fast-growing tumours. Furthermore, T cells can become exhausted, and some tumour types learn to evade them, allowing them to dodge the immune system altogether. This is where immunotherapy has the advantage. It involves extracting patients' T cells, and, using gene transfer, introducing receptors that will target a specific cancer cell. Once returned to the patient, the ‘engineered’ T cells regenerate to create a clone of immune cells that attach the tumour.
Using this technique, sustained regression has been seen in previously terminal cases of acute lymphoblastic leukaemia, non-Hodgkin lymphoma and chronic lymphocytic leukaemia.