A 3-year-old boy became the first recipient of gene therapy to treat a fatal disease

According to RCO News Agency, Hunter syndrome is a rare, progressive, inherited disorder that damages the body and brain. This rare and progressive disease destroys the body and brain, and its effects are often compared to a form of childhood dementia. This condition is life threatening and the life expectancy of these patients is usually between 10 and 20 years.

According to AI, this treatment was developed over 10 years at the University of Manchester and tested at the Royal Manchester Children’s Hospital (RMCH). This procedure is done only once. Ollie received gene therapy in February 2025 and has fully recovered a few months after the operation.
“Gene therapy is not only safer and more effective, but also allows us to use the child’s own cells,” says Professor Rob Wynne, a pediatric hematology specialist and director of the Children’s Bone Marrow Transplant Program. This eliminates the need to find a donor and allows us to produce more enzymes for the patient.

gene therapy
This disease, also known as mucopolysaccharidosis type II (MPS II), is caused by a defective gene that prevents the body from producing a vital enzyme.

Without this enzyme, complex sugar molecules (mucopolysaccharides) accumulate in organs and tissues and lead to progressive damage including dry joints, hearing loss, heart and respiratory problems, developmental delay and cognitive decline (childhood dementia).

Currently, the approved treatment is enzyme replacement therapy (ERT) with the expensive drug Elapris, which is given weekly and for life. Elapris can control physical and organ problems, but is unable to treat or improve mental decline due to inefficient crossing of the blood-brain barrier.

In this clinical study, experts used a gene therapy that involves taking the child’s stem cells, modifying the defective gene in the laboratory, and re-injecting the modified cells into the patient’s body.

These modified cells are able to produce high levels of the missing enzyme. More importantly, the treatment reaches the brain and breaks down the build-up of toxic sugars, which is hoped to prevent dementia-like cognitive decline.

Professor Simon Jones, a specialist in pediatric inherited metabolic diseases at St. Mary’s Hospital Genomic Medicine Center, says: “Since receiving the gene therapy, Ollie no longer has weekly injections of Elaparis, but instead of reducing the enzyme level, we see a very high level of it in his blood, and this is a very promising sign of the effectiveness of the treatment.”

The first of five children

The treatment began with Ollie, a California resident, who is the first of five Hunter syndrome patients in the trial. His older brother, Skyler, also has Hunter syndrome, but was ineligible for the test because of his advanced age. Ollie’s father, Ricky Chu, says: Ollie is doing great after the gene therapy. We have seen dramatic improvements and he continues to grow physically and mentally. Our hope is that Oli will be able to produce his own enzymes thanks to this treatment and live a normal life without injections. We are excited for Ollie’s future. Seeing the difference before and after transplantation has led us to believe in the effectiveness of this treatment.

The researchers emphasized that the success of this blood cell-based gene therapy approach provides an exciting model for the treatment of many other genetic diseases.

end of message