Immunotherapy is one of the most promising ideas to arise in cancer treatment for a long time. It is a field that is focused on genetic engineering of a patients own immune cells to combat cancerous cell activity. The 54th Annual American Society of Hematology (ASH) meeting saw the presentation of two major study results, both looking into the effect of genetically-modified T-Cells on multiple myeloma (MM) – a type of cancer related to lymphoma and leukaemia that occurs in the bone marrow.
The idea behind immunotherapy is based on the basic theory of introducing a desired gene into a cell to produce a desired protein. In this case, a gene was introduced into T-Cells harvested directly from the patient that caused a high expression of T-Cell receptors (TCRs) that specifically targeted an epitope found in both NY-ESO-1 and LAGE-1 tumour antigens. The theory is that the higher amount of receptors the T-Cells possess, the greater efficiency the cells will have in attaching to the target antigens and killing the tumour cells.
The first paper presented by Dr. Aaron Rapoport (link below) showed that in a sample of 11 infused patients, 3 had a complete response (no sign of tumour antigen protein), 7 had a very good partial response (levels of antigen protein are 90% lower than original amount) and 1 had progressive disease. These numbers were taken from patients that were receiving standard treatment of melphalan (chemotherapy agent) alongside T-Cell infusion.
The second paper to emphasise the importance of these findings was presented by Dr. Michael Kalos (link below). Presented alongside Dr. Rapoport’s paper, Dr. Kalos demonstrated the persistence of their genetically-modified T-Cells. The engineered cells were found to be incredibly durable and efficient in their targeting of tumour cells expressing the NY-ESO-1 and LAGE-1 tumour antigens.
Not Only Are They Efficient, They Stick Around Too…
As Dr. Kalos mentions in his own abstract of the study, engineered T-Cells correlate positively with treatment response rates however it is their lack of persistance that taints their reliability. For patients with MM, any form of treatment that can produce such incredible numbers of remission is truly ground-breaking. MM is currently seen as an incurable disease but advances such as these are already bringing much hope in the quest to defeat it. Results suggesting persistance and efficiency therefore can be considered a remarkable feat and something to be looked further into. Although it should be noted that these findings were demonstrated while using engineered T-Cells alongside standard treatment, it can not be ignored that the impact of these cells is huge when considering the usual response rate (33%-69%) and new response rate (highest of 77%).
Consider the impact on other cancer treatments: will chemotherapy actually be needed to fight cancer if the resources are already circulating through the patient? Will those cancers that have a high recurrence rate no longer recur as often? Can those cancers that are essentially a death sentence finally have some form of treatment? Until further trials are taken and results are gathered we can only hope for positive answers. So far, things are looking promising.
Dr. Rapoport’s study submission:
Dr. Kalos’ study submission:
Image courtesy of: http://www.nature.com/nri/journal/v12/n4/fig_tab/nri3191_F2.html