A one year-old girl has become the first person to be successfully cured of leukaemia by a “designer” immune cell therapy.
Layla Richards was diagnosed with cancer at just 14 weeks old after going off her milk and developing a fast heartbeat.
A blood test confirmed Layla had an aggressive type of acute lymphoblastic leukaemia, the most common form of childhood leukaemia.
She was cured after scientists used a new gene-editing technique to manipulate cells to fight the disease at Great Ormond Street Hospital (GOSH) in central London.
The therapy has previously been tested only on mice in the laboratory. 
Chemotherapy has been known to cure leukaemia but for Layla, like many other patients, the disease is so aggressive that some cancer cells remain hidden or fight the drug.
Recent studies have suggested that immune cells, known as T-cells, can be gathered from patients and programmed using gene therapy to recognise and kill cancerous cells.
But this treatment would not have worked for Layla as she did not have enough healthy T-cells after the rounds of chemotherapy she had undergone.
Layla also underwent a bone marrow transplant which failed to work.
Doctors told Layla’s parents that there was nothing left that could cure Layla, and suggested palliative end-of-life care but her family refused to give up on her.
The family was then offered an experimental treatment under development at the hospital, in which doctors modified T cells, from a healthy donor so that they seek out and kill drug-resistant leukaemia.
Layla was given a small infusion of the genetically-engineered cells known as UCART19 cells. A few weeks later, consultants told her parents that the treatment had worked.
Following the treatment, Layla spent months in isolation but is now free of cancer and recovering well at home.
Doctors stressed that the experimental technique had just been used once and that the results need to be replicated, but said it was potentially very promising.
“If replicated, it could represent a huge step forward in treating leukaemia and other cancers.”