World 1st: Cancer cured by 'designer cells'

An extra gene is added to cells which makes them target leukaemia cells. Photo / iStock

A baby girl suffering aggressive leukaemia has become the first in the world to be treated with designer immune cells, genetically engineered to wipe out her cancer.

One-year-old Layla Richards was given just months to live after conventional treatments proved unsuccessful in curing her.

Now, she is cancer free, a response one doctor described as "almost a miracle".

Two months prior, specialists at Great Ormond Street Hospital (GOSH) in London began treatment, but stressed that it could be more than a year before they would know for certain whether the therapy had eradicated the disease or merely slowed it's progression.

"We have only used this treatment on one very strong little girl, and we have to be cautious about claiming this will be a suitable treatment option for all children," Waseem Qasim, professor of cell and gene therapy at University College London's Institute of Child Health, and a consultant immunologist at GOSH, told The Guardian.

But, he said it is "a landmark in the use of new gene engineering technology and the effects for this child have been staggering".

Baby Layla was born healthy, but at three months, went off her milk, cried more than usual and developed a fast heartbeat.

While doctors suspected a stomach bug, blood tests revealed acute lymphoblastic leukaemia (ALL).

Layla and her family were sent by ambulance to GOSH and the baby placed in intensive care with what the doctors described as the most aggressive form of the disease they had ever seen. Only 25 per cent of children tend to survive ALL.

The following day, Layla began chemotherapy and had a bone marrow transplant to replace damaged blood cells. But after several rounds of treatment, the disease returned and doctors suggested palliative care.

However, Layla's parents, Lisa and Asleigh, insisted the doctors keep trying.

"We didn't want to accept palliative care and give up on our daughter, so we asked the doctors to try anything for our daughter, even if it hadn't been tried before," Lisa said.

A potential cure

The hospital had been working on an experimental cell-based treatment for leukaemia and while the research had twice shown that the modified cells had an anti-cancer effect, it had only been tested on mice.

They had just a single vial of the cells to give to Layla, but needed approval from both her parents and the emergency ethics committee to proceed.

Doctors explained to the family there was no guarantee it would work, but Ashleigh said while it was scary to think the treatment had never been used on humans before, they felt they had to try.

How the treatment works

Layla received a 1ml infusion of the genetically engineered immune cells administered under special UK therapy regulations. The infusion took 10 minutes.

The miniscule amount of fluid concerned her parents: "We thought that the little bit of liquid in the syringe was nothing and asked 'what is that going to do when bags and bags of chemo haven't worked?'."

The cells were extracted from donated batches of frozen T cells, or white blood cells - which play a central role in immunity.

Before they are infused, an extra gene is added to the cells which makes them target leukaemia cells. They also have other genes disabled to stop them attacking the receptive patient and to make them invisible to a drug used to suppress patients' immune systems.

Layla's results

It was expected Layla would develop a rash within one to two weeks of the infusion, a sign the treatment was working.

But it wasn't until the two week mark was up and Layla was being prepared to be sent home that the rash appeared. The cells were having an effect.

Weeks later, while Lisa while she was collecting their eldest daughter from school, Ashleigh called to say the consultants had been in touch with results.

"I thought it was bad news," said Lisa. "But then he said, 'it's worked' and I just cried happy tears."

Two months on, Layla remained clear of Leukaemia. Doctors proceeded with a second bone marrow transplant to replace her blood and immune system completely. A month later she was well enough to go home.

Another patient is now receiving the treatment under a different medical team.

Clinical trials of the cells are due to begin early next year and, if replicated, "it could represent a huge step forward in treating leukaemia and other cancers," said Qasim.

- nzherald.co.nz