A baby girl in the UK has been cleared of leukaemia following an experimental immunotherapy using gene-edited cells.
It is the first time a therapy using the gene-editing technology TALENs (transcription activator-like effector nucleases) has been used in a human.
The treatment on Layla Richards, was only sanctioned because the girl had no other hope of surviving the acute lymphoblastic leukaemia (ALL).
Doctors used modified T-cells from donors, known as UCART19 cells, to treat Layla.
“The approach was looking incredibly successful in laboratory studies,” says Professor Waseem Qasim, a consultant immunologist at the hospital.
“And so when I heard there were no options left for treating this child’s disease, I thought, ‘Why don’t we use the new UCART19 cells?’
“The treatment was highly experimental and we had to get special permissions, but she appeared ideally suited for this type of approach.”
The results of the trial have not been published, but will be presented at the American Society of Hematology next month.
Experimental treatments involving cutting and editing genes to reprogram cells is an area that is developing rapidly, as we discussed in Cosmos magazine recently (see New hope for cancer medicine)
“TALENs function as ‘molecular scalpels’ that cut DNA and inactivate a target gene. The group targeted two genes: one involved in formation of the T-cell receptors and another that sensitizes cells to a monoclonal antibody,” explained Dr. Mark Osborn, Assistant Professor, Department of Pediatrics, Division of Blood and Marrow Transplantation, University of Minnesota.
“This first in-human use of TALEN engineered cells is designed to fill a critical gap for the treatment of acute lymphoblastic leukemia, the most common type of childhood cancer that has a poor prognosis,” he said.
“This study merged genome editing technology with an existing immunotherapy, whereby T cells are engineered to have receptors on their surface, called chimeric antigen receptors (CARs), which recognise and target tumour cells.
“Previous CAR-based therapies have utilised a patient’s own cells which means treatments have to be individually manufactured.”
