Breakthrough for worst cases of childhood leukaemia

Scientists have developed a new way to deliver toxic cancer drugs selectively to cancer cells, making treatments safe and more effective.

Chemotherapy is the primary treatment for aggressive blood cancers, also known as leukaemias, which are most common in children aged under 15.

Australian researchers have developed a way to deliver toxic cancer drugs selectively to cancer cells, which could eventually increase survival rates in high-risk leukaemia patients and reduce the devastating side-effects of chemotherapy in children.

Chemotherapy is the primary treatment for aggressive blood cancers, also known as leukaemias, which are most common in children aged under 15. But high doses of these toxic drugs affect both cancer cells and healthy cells, causing very severe and ­debilitating side-effects.

Of the kids who survive treatment, two-thirds experience side effects for life.

Scientists at the Children's Cancer Institute developed a way to selectively target cancer cells by adding “bi-specific antibodies” to an existing cancer drug called Caelyx. These antibodies attach to the cancer drug at one end and the cancer cell at the other end, delivering the drug directly to the cancer cell and killing it.

When the researchers tested this method on cells taken from children with leukaemia and specially bred mice, it reduced the amount of cancer and prolonged survival by up to four times. These findings were published in Science Translational Medicine.

“We believe the controlled targeting of nanotherapeutics represents a real milestone in the treatment of childhood cancers, and we’re very optimistic,” lead researcher Professor Maria ­Kavallaris said.

“We’re really hoping this leads to a treatment which is dramatically less toxic because it’s more targeted, but also flexible.

“In the future, it may be that each child diagnosed with leukaemia can have their treatment targeted to their specific subtype,” she added.

Matt Weston has witnessed the incapacitating side-effects of chemotherapy first hand. His son Jacob was diagnosed with standard-risk leukaemia on Christmas Day 2021 at just four years old. What followed was more than 50 chemotherapy infusions, 10 blood transfusions, numerous lumbar punctures and more. Mr Weston describes it as “seven months of Jacob being absolutely batted by an incredibly toxic treatment regimen”.

Jacob suffered from mucositis, which effects the gastrointestinal tract. “He could barely speak, he was in that much pain. He couldn’t eat … He had to go on morphine – a little kid on morphine,” his father said.

Now six, Jacob is getting back to some sort of normalcy. He’s back at school, but the chemotherapy medications still effect his stamina and strength. “It hangs over the family as a bit of a dark cloud,” Mr Weston said.