New gene-editing technique puts 90pc of leukaemia patients into ‘deep remission’

LEUKAEMIA sufferers have been given hope of a potential cure after a breakthrough gene-editing technique put 90 per cent of patients in a trial into “deep remission”.

Patients with the most common adult form of the disease, chronic lymphocytic leukaemia (CLL), had blood transfusions after their own cells were re-engineered to attack cancer cells.

Six months after starting the three-day, one-off treatment doctors found no evidence of the disease in the bone marrow of all but one of the nine participants.

Cancer research campaigners have hailed the results as “very promising”. CLL currently causes more than 1,000 deaths in the UK each year.

The personalised cellular approach, known as CAR-T therapy, was given to those who had failed to fully respond to six months of the daily oral drug ibrutinib.

The University of Pennsylvania scientists behind the trial, which has now been expanded to 271 patients, believe the gene-editing technique holds such potential that doctors should prescribe it as an attempted cure in the first instance.

“The hope is that because we have seen such deep responses it means the patients are in such deep remission that the disease will never come back,” said associate professor Saar Gill, the first author on the study, which was presented to an American Society of Clinical Oncology conference in Chicago. The gene-transfer technique is designed effectively to teach a patient’s removed cells to target and kill tumour cells by using a protein known as a chimeric antigen receptor (CAR) which binds to a protein on the dangerous cancer cells.

Dr Alasdair Rankin, the director of research at the British blood cancer research charity Bloodwise, said the findings were “clearly very promising” – but warned that the small study was still in its“very early days”.

Currently, one in two patients survives for 10 years after being diagnosed with the disease.

But medical leaders believe gene editing, immunotherapy, and better methods of detecting tumours before they spread, will soon raise that rate by 50 per cent.

“The immune therapies are really going to substantially improve the long-term disease control for some patients,” said Dr Richard Schilsky, senior vice president and chief medical officer at the American Society of Clinical Oncology.