A mother in Swansea is racing to raise almost £3 million for a treatment that could change the life of her five-year-old son, after the first gene therapy for his rare condition was approved in the United States.

Tate McDaid was diagnosed with Sanfilippo syndrome when he was four. The condition, sometimes described as childhood dementia, gradually takes away abilities that most children build on year after year, including walking and eating. Just over 100 children in the UK have the condition.

In September, the first gene therapy to treat the condition in children was approved in the US. The one-time treatment, called FAYUVI and developed by the company Ultragenyx, has been priced at 3.95 million dollars in the United States — about £2.95 million per child. For families in Britain, where the treatment is not yet available, that figure is the starting point of a fundraising effort few could ever complete alone.

A race against time

Tate's mum Tammy said she spent months praying for the drug's approval, but discovered the cost the next day. She has now raised more than £160,000 — only about 5 per cent of the total estimated cost.

There is no cure for Sanfilippo syndrome Type A, also called Mucopolysaccharidosis type III (MPS III), but the new drug could delay its onset and allow Tate to remain active for longer. The condition can progress more rapidly after the age of five, and Tate turns six this month. He is already showing early signs of cognitive decline, and he has always been non-verbal.

Access from the UK still unclear

Health officials from Wales are currently talking to those in the US to see what potential access pathways there are for Tate, and staff at Noah's Ark Children's Hospital in Cardiff are discussing the case with officials in the US on the family's behalf.

[Source: everywherenews.net](https://www.everywherenews.net/news/articles/c8046kdw56e2o) | [Source: discover.swns.com](https://discover.swns.com/2026/10/mum-in-race-to-raise-3m-for-son-with-rare-childhood-dementia/)