A young boy born with a devastating, rare genetic condition has been given a new lease of life thanks to a team of UCL scientists who manufactured a pioneering gene therapy for him.
Ollie Chu was born with Hunter syndrome – or MPSII – an inherited, life-limiting genetic condition which causes progressive damage to the body and brain.
In the most severe cases, patients with the disease usually die before the age of 20. The effects are sometimes described as a type of childhood dementia.
Due to a faulty gene, before the treatment Ollie was unable to produce an enzyme crucial for keeping cells healthy.
But in a world first, scientists at UCL have altered Ollie’s cells using gene therapy in a bid to halt the disease.
His parents are thrilled at Ollie’s progress which they say they has been “exponential” since his transplant. He is being treated in hospital in Manchester.
Dr Karen Buckland (UCL Great Ormond Street Institute of Child Heath) said: “It’s really heart-warming to hear how well Ollie is doing – his progress is amazing.
“It’s also really, really rewarding for the team here. A lot of hard work has gone into manufacturing this new gene therapy. As well as the core team of five, around 50 staff were involved in total including all the clinical trial co-ordinators, project managers and quality assurance staff.
“It took two years just to check that the manufacturing process worked correctly. We then had to get regulatory approval before we could even begin treating Ollie’s cells.”
Dr Buckland and three other of her UCL Institute of Child Heath colleagues were directly involved with manufacturing his cells: Dr Winston Vetharoy, Edward Morgan and Raymond Nguyen. The fifth member of the team was Agrim Mahajan, from Great Ormond Street Hospital.
Dr Buckland said the project came about because she and colleagues had worked successfully on a previous project with the same Manchester team on a treatment for a similar condition called Mucopolysaccharidosis type III (MPS III) or San Filippo Syndrome.
In 2019 the Manchester team, then led by Professor Brian Bigger, approached Dr Buckland and her team again and asked them to manufacture the treatment for Hunter’s Syndrome.
In 2021 the UCL team began the process of checking the manufacturing process worked correctly.
That process, which is the first outside-of-the-body gene therapy to treat the condition, involves purifying a patient’s white blood cells to retrieve their stem cells, which are then added to a specialist growth medium.
A working copy of the gene is then added to a viral vector, which is used to transport the healthy copy of the gene into the patient’s own stem cells.
The cells are then washed and frozen and stored at -130 degrees C, in a process known as cryopreservation.
The cells are checked using several quality control tests to make sure they’re safe to be given back to the patient.
Having confirmed, in 2022, that the process worked correctly the University of Manchester applied successfully to the UK medicines regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), for approval. They could then use the process on a patient.
Ollie, from California, is the first of five boys around the world to receive the treatment.
The team treating him at Royal Manchester Children’s Hospital (RMCH) sent Dr Buckland and her colleagues some of his white blood cells.
Dr Vetharoy, who led the manufacture of the gene therapy product for Ollie, said: “Every stage of the process required meticulous attention to detail. We needed to maintain absolute control over contamination risks and ensure that all reagents and materials met the highest-quality standards.
“Seeing how well Ollie is thriving after such a short time is incredibly fulfilling for the entire team, and we wish him continued progress and good health in the years to come.”
In November 2024, the UCL manufacturing team made the altered cells for him, using the validated manufacturing process. In February 2025, those altered cells were transplanted into Ollie’s body.
Nine months on, his father, Ricky, says the improvement in his son’s condition is remarkable.
He said: “I don’t want to jinx it, but I feel like it’s gone very, very well. His life is no longer dominated by needles and hospital visits. His speech, agility and cognitive development have all got dramatically better.
“It’s not just a slow, gradual curve as he gets older, it has shot up exponentially since the transplant.”
Currently the only licensed treatment that can help to improve life for children with Hunter syndrome is Elaprase – a weekly enzyme replacement therapy that takes approximately three hours to administer, that children must take for their whole life.
Dr Buckland and her colleagues manufactured the new gene therapy treatment at the specialist Cell and Gene Therapy Manufacturing Facility in The Zayed Centre for Research (ZCR) into Rare Diseases in Children, a facility jointly run by UCL and GOSH.
The clinical trial at RMCH is being done in collaboration with University of Manchester and the Manchester Centre for Genomic Medicine at Saint Mary’s Hospital.
Source: University College London
