While most young victims of the Sanfilippo syndrome seldom live beyond their teen years, Tillie Mae Mawdsley from Hertfordshire in England was believed to have had it better – she was more mobile and verbal.

For the girl who has suffered from the rare degenerative disorder since her early years, the trial treatment was revolutionary, especially when her parents had pinned all hopes on it, however fleeting it might have been. They saw the treatment as giving her a quality of life and believed it made her better.

Her mother, Michala Mawdsley said, “I feel that she's doing better than some children we have met who haven't had the treatment.”

Likened to a form of childhood dementia, the rare disease also known as MPS III, is caused by a missing enzyme which results in a build-up of sugar around the muscles, and patients go through a regressive journey of progressive damage.

“It's memory loss, the disease attacks the brain,” Mrs Mawdsley said, adding that Tillie Mae has no understanding of what is happening to her.

The treatment involved her travelling 400 miles to and fro Manchester Children’s hospital every month where she was given the drug via a port inserted into a spine, which was directed into the cerebrospinal fluid (CSF) to cross the blood brain barrier.

"It was a huge risk for us to take but I felt like I was doing something. I'm grateful that we were part of it,” she said.

Drug trial halted due to lack of efficacy in results

Tillie Mae was one of six children in the UK who went on the enzyme replacement therapy (ERT) by Shire, a US pharmaceutical company. But after six years, the sudden stop to the clinical trial has put the family at wit’s end, frantically seeking a cure as Tillie Mae may soon start to degenerate, unlearning all that she has learnt.

Shocked, her mother said, “We feel like the rug has been pulled from beneath us and she's been handed a life sentence. It's difficult to accept there's nothing we can do for her now. 

“Being part of something made us feel like we were going somewhere so it's been a massive blow but we have to be strong for Tillie Mae.”

Mrs Mawdsley was disappointed that they were not given any reasons. “We were grateful that she had the opportunity but she stayed the same and that was enough for us. They wanted to see a change in children and argued the drug wasn't causing any cognitive improvement. 

“We just feel after six years Shire should have had enough evidence before then to say if it was not working,” she stressed.

No approved treatment options

A spokesman for Shire said, “The results did not show any slowing of disease progression in these patients compared to control (untreated) patients.”

“Shire is extremely disappointed to have announced that this Phase 2b study did not meet its primary endpoint of slowing the cognitive decline in patients,” he added.  

The pharmaceutical company also expressed sympathy for the “Sanfilippo community” and thanked all the patients and their families for their willingness to participate in the trials. But Tillie’s parents are not giving up; they are raising funds to raise awareness of the disease and to aid future research.

Mrs Mawdsley said, “She’s got everything to live for and a right to live but just because it’s rare, there is no cure.”

“For now we're continuing to make memories and just living day by day, taking each day as it comes before Tillie Mae runs out of time.” MIMS

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