UK Gene Therapy Shows Promise for Children with Hunter Syndrome
A novel gene therapy,developed by researchers in Manchester,UK,is offering cautious optimism for children battling Hunter syndrome,a devastating inherited disorder. The first patient, three-year-old Oliver Chu from California, received the treatment nine months ago as part of a clinical trial conducted at the Manchester Center for Genomic medicine (MCGM) at Saint Mary’s hospital and Royal Manchester Children’s Hospital.
Hunter syndrome stems from a faulty gene that prevents the body from producing an enzyme crucial for breaking down complex sugar molecules. These accumulating molecules lead to a range of severe symptoms, including joint stiffness, hearing loss, heart problems, and progressive cognitive decline, ultimately impacting life expectancy to typically 10-20 years.
Currently, the only approved treatment, Elaprase, is a costly weekly infusion - priced around £375,000 per patient for life – that replaces the missing enzyme. Though, Elaprase doesn’t reach the brain, leaving cognitive decline unchecked.
The experimental one-time therapy involves collecting stem cells from the patient’s blood, correcting the faulty gene with a functional copy, and then re-infusing the modified cells back into the bloodstream. These corrected cells then begin producing the necessary enzyme, crucially, reaching the brain.
Following the therapy in February, Oliver no longer requires weekly Elaprase infusions, a significant indicator of the treatment’s potential success. Prof Simon Jones, consultant in paediatric inherited metabolic disease at MCGM, emphasized the need for continued observation: ”Things look really hopeful right now, but Ollie was the first human to receive this therapy and it’s only been nine months out… We have four more boys scheduled in and we will need to prove the benefit is long-lasting.”
Oliver’s father, Ricky Chu, shared encouraging observations with the BBC, noting dramatic improvements in his son’s speech, agility, and cognitive progress. ”His life is no longer dominated by needles and hospital visits,” he stated.
The trial includes five boys from the US, Europe, and Australia. The researchers hope the therapy may also benefit oliver’s older brother, Skyler, who also has Hunter syndrome, though the therapy cannot reverse existing damage. Skyler, at five years old, currently shows limited effects of the condition.
Hunter syndrome is exceptionally rare, affecting approximately one in 100,000 males globally. Researchers highlight the importance of early diagnosis, noting that newborn screening – standard in the US – is crucial for identifying patients eligible for treatment. The team is also exploring the request of this gene therapy approach to other genetic disorders impacting vital enzymes,including Hurler syndrome and Sanfilippo syndrome.
