This groundbreaking therapy can reverse incurable blood cancer
09 Dec 2025

A groundbreaking therapy has successfully reversed aggressive and incurable blood cancers in some patients, doctors have reported.

The innovative treatment uses precise DNA editing of white blood cells to create a "living drug" that fights cancer.

The first patient to receive this treatment, a girl whose story was covered in 2022, is still free from the disease and now plans to become a cancer scientist.

High success rate in clinical trials
Trial results

The revolutionary therapy has been administered to eight more children and two adults suffering from T-cell acute lymphoblastic leukemia.

An impressive 64% of these patients are now in remission.

The treatment was a last resort for those on the trial, as chemotherapy and bone marrow transplants had failed to cure their condition.

Patient's journey and future aspirations
Personal story

One of the patients, 16-year-old Alyssa Tapley from Leicester, UK was the first person in the world to receive this treatment at Great Ormond Street Hospital.

She had to spend four months in isolation due to her weakened immune system but is now living a healthy life with undetectable cancer.

Alyssa plans on pursuing an apprenticeship in biomedical science and hopes to work in blood cancer research one day.

The science behind the revolutionary therapy
Treatment mechanism

The team at University College London (UCL) and Great Ormond Street Hospital used a technology called base editing for this treatment.

This method allows scientists to zoom into a specific part of the genetic code and change one base's molecular structure, rewriting the instruction manual of DNA.

They engineered healthy T-cells from a donor to hunt down bad ones without self-destruction, making it an incredibly complex process.

Genetic modifications and treatment infusion
Treatment details

The first genetic modification disabled the T-cells' targeting mechanism so they wouldn't attack the patient's body.

The second removed a chemical marking, CD7, which is present on all T-cells. This was done to prevent self-destruction of the therapy.

The third edit was an "invisibility cloak" that protected the cells from being killed by chemotherapy drugs.

Finally, the modified T-cells were instructed to hunt anything with CD7 marking on it.

Immune system regrowth and treatment success
Success rate

This therapy is infused into patients and if their cancer can't be detected after four weeks, then they undergo a bone marrow transplant to improve their immune system.

The study published in the New England Journal of Medicine shows that out of the first 11 patients treated across Great Ormond Street and King's College Hospital, nine achieved deep remission, allowing them to go for a bone marrow transplant.