Gene-editing research update

16 Mar 2017, 11:11 a.m.

Child patient in a cot.

On Wednesday 25 January, details of two patients successfully treated for their leukaemia at Great Ormond Street Hospital using gene-editing technology were published in the journal, Science Translational Medicine. One of the patients was Layla (pictured) who was the first person in the world to receive gene-edited immune cells to treat drug resistant leukaemia. Her story received widespread national and international media coverage.

Commenting on the publication, Professor Waseem Qasim, Professor of Cell and Gene Therapy at UCL Great Ormond Street Institute of Child Health (ICH), Consultant Immunologist at GOSH and who carried out the work, said: “We are delighted to have shown that gene-edited cells can successfully treat leukaemia that has not responded to standard treatments.

“While both patients are now at home and are doing well, we must treat these results with some caution as we don’t yet know if the technique will be successful in treating a larger number of patients. Clinical trials are currently underway to assess this.”

The treatment

The treatment used ‘molecular scissors’ to edit genes and create designer immune cells programmed to hunt out and kill drug resistant leukaemia. The breakthrough came from pioneering research teams at GOSH and the ICH, with support from the National Institute for Health Research (NIHR) Great Ormond Street Biomedical Research Centre, who together are developing treatments and cures for some of the rarest childhood diseases.

Chemotherapy successfully treats many patients with leukaemia but it can be ineffective in patients with particularly aggressive forms of the disease where cancer cells can remain hidden or resistant to drug therapy. Recent developments have led to treatments where immune cells, known as T-cells, are gathered from patients and programmed using gene therapy to recognise and kill cancerous cells.

A team at GOSH used modified T-cells from donors, known as UCART19 cells, to treat Layla, for whom palliative care was deemed the only option left, and another patient.

Professor Qasim described the treatment as “a landmark in the use of new gene engineering technology which represents a huge step forward in treating leukaemia and other cancers."