In work to be presented at the American Society of Haematology annual meeting in December scientists have described their work using gene editing techniques in attempt to treat a patient with relapsed acute lymphoblastic leukaemia. It is thought to be the first time this technique has been attempted in a person with leukaemia. These comments accompanied a briefing.
The SMC produced a Factsheet on genome editing.
Dr Yalda Jamshidi, Senior Lecturer in Human Genetics, St George’s University Hospital Foundation Trust, said:
“Gene editing is an exciting scientific advance with potential to treat many human genetic diseases. The GOSH/ICH group have successfully edited donor immune T cells using a genome editing technology using tool called TALENs, and used it to treat a young patient with leukaemia who didn’t respond to chemotherapy. Importantly, unlike recent controversial reports of gene editing in human embryos with another technology (CRISPR/Cas9), modifications made to the T cells should not be passed on to future generations. The results of the current study are very promising, and further work needs to be carried out to show long term efficacy, confirm lack of toxicity of the engineered cells and applicability to a wider patient population.”
Dr Simon Waddington, Reader in Gene Transfer Technology, UCL, said:
“There has been recent work by several groups in Europe and the US using gene therapy tools to modify patient T cells to treat cancer; many have yielded very promising results. However this report is exciting for two reasons.
“Firstly, conventionally, gene therapy has been used to deliver extra copies of genes to cells which have no working copies – slightly inelegant although it has worked in quite a number of clinical trials. This new case describes the use of gene editing technology (in this case TALENs) to carefully, and specifically modify existing genes – taking genetic medicine to a new level of precision.
“Secondly, the researchers have used this technology to create an off-the-shelf, generic cell therapy, rather than one specifically tailored for an individual patient. Therefore this could reduce the cost and complexity of the treatment, and ultimately bring benefit to a wider patient population. Nevertheless, this is a very early report and the researchers will now rigorously scrutinise the long-term safety and efficacy of the treatment so more work has yet to be done before this is a technology available to all.”
Dr Matt Kaiser, Head of Research at Bloodwise (previously Leukaemia & Lymphoma Research), said:
“Survival rates for this type of childhood leukaemia are thankfully now high, but there remains a desperate need for less toxic drugs and new treatments for the minority of patients who cannot currently be cured. The concept of training immune cells to specifically recognise and hunt out leukaemia cells is very exciting and in theory could provide a lifetime cure for these children.
“There have been other cases of children who are still in remission after years of receiving similar experimental treatments, but the technique is still in the very early stages of development. This new type of ‘off-the-shelf’ T-cell therapy could represent a significant advance. The next step needed is for it to be tested in larger clinical trials. We need to establish whether it can offer a long-term cure, whether there are any side effects and which patients are most likely to benefit from it.”
Abstract title = ‘First application in man of TALEN engineered universal CAR19 T cells in B-ALL’ by Waseem Qasim et al. is unpublished work; the case will be presented at the American Society of Haematology annual meeting in Florida in December.
Dr Yalda Jamshidi: “I have no interests to declare.”
Dr Simon Waddington: “I have collaborated with Adrian Thrasher in the past, and I know Waseem Qasim, Kimberly Gilmour and Martin Pule. I am also based at UCL.”
Dr Matt Kaiser: No interests to declare.