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Saving Eliza: Gene therapy offers new hope for girl with 'childhood Alzheimer's'

Eliza O'Neill's parents call it their miracle. She's finally the first patient to receive an experimental therapy for her deadly disease.
/ Source: TODAY

Eliza O'Neill’s parents call it their miracle story. After years of fundraising, 726 days of self-imposed isolation and non-stop determination to save their 6-year-old daughter’s life, she has finally become the first patient in the world to receive an experimental gene therapy for her deadly disease.

Eliza O'Neill, who has Sanfilippo syndrome.
Eliza O'Neill has Sanfilippo syndrome, which occurs in one in 70,000 births.Courtesy O'Neill family

“We have tons of hope for Eliza now. So much more hope,” Glenn O'Neill, her dad, told TODAY. “I never used to think about the future, because I didn’t want to. But now, I do think about it.”

Eliza has Sanfilippo syndrome, a rare disorder that affects the brain and progressively robs children of language and understanding. Some call it “childhood Alzheimer's.” Most victims eventually become immobile and don't live beyond their teens. Eliza has type A, the most severe form of the disease.

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Eliza O'Neill gets treatment for Sanfilippo syndrome
Eliza received her gene therapy at Nationwide Children's Hospital in Columbus, Ohio, in May.Courtesy O'Neill family

On May 10, doctors at Nationwide Children's Hospital in Columbus, Ohio, injected a harmless virus that delivered the therapy into Eliza’s bloodstream, a 30-minute procedure that capped years of efforts by her parents to find a cure.

“The waiting was excruciating,” O'Neill, 43, said. “There was no relief until it happened… and they came out of the room and said she was doing fine.”

Eliza O'Neill has Sanfilippo syndrome
The O'Neill family includes mom Cara, Eliza, brother Beckham and dad Glenn.Courtesy Anna Tenne Photography

When Eliza was diagnosed in 2013, the O'Neills, who live in Columbia, South Carolina, discovered researchers had developed a gene therapy that appeared to work in mice. But they couldn't get adequate funding for tests in humans, so the family raised more than $1.8 million for clinical trials in children through the "Saving Eliza" campaign.

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They had no guarantee their daughter would be able to take part. To give her the best chance possible, the family went into seclusion in 2014 to prevent Eliza from building up immunity to the virus that would deliver the gene therapy. Had that happened, she would have been excluded from the clinical trial, her dad said. Their self-imposed isolation ended recently after almost two years.

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As the family hoped and waited for a spot in the trial, Eliza was steadily declining.

“She went from saying sentences and singing songs, to a word or two of that sentence or song, to not saying those things,” her dad recalled. “Even then, it’s a syllable of a word or having trouble putting two syllables together… it’s just absolutely devastating.”

Eliza O'Neill has Sanfilippo syndrome
Eliza is the first patient in the world to get the gene therapy.Courtesy Anna Tenne Photography

Children with Sanfilippo syndrome are missing an enzyme needed to break down long chains of sugar molecules in the body, causing progressive damage.

Eliza’s experimental therapy involves a harmless virus that acts like a delivery truck, carrying a normal copy of the gene that makes the enzyme into the girl’s cells, her mom Cara O'Neill explained. The hope is the girl’s body will translate that gene and fix the problem.

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Eliza O'Neill has Sanfilippo syndrome
It took about 30 minutes to inject Eliza with the gene therapy at Nationwide Children's Hospital in Columbus, Ohio.Courtesy O'Neill family

It's an experiment and she's the first person to take part, so no one knows how well it will work in stopping or reversing Sanfilippo syndrome.

Gene therapy is a promising treatment option for some diseases, but it's still experimental and risky, the National Institutes of Health warns. It's only tested for incurable diseases and studies continue to see if it is safe and effective.

The results in Eliza so far are encouraging.

“There’s been improved interaction and engagement with her,” Cara, 41, noted. “It used to be more she was passing by us, looking through us. But now, she’s engaged and seeking really good eye contact and trying to talk.”

“We’re seeing this renewed light in her eyes. This clarity, focus — whatever is happening, it seems her body is able to relax more,” Glenn added.

Eliza O'Neill has Sanfilippo syndrome
There's new hope for Eliza, her parents say.Courtesy O'Neill family

The O'Neills now want to raise more money for other Sanfilippo families to make sure they also have a chance to see their kids take part in clinical trials and improve. They’ve released a new video as a follow-up to the viral clip that first drew attention to Eliza’s story two years ago.

There are hundreds of families waiting for a spot in a clinical trial, but few opportunities available, Glenn said. He wants every parent to feel the hope he feels.

“Eliza’s future is uncertain right now and that’s a fabulous thing for a Sanfilippo parent because prior to treatment, Eliza’s future was definite: suffering, degeneration, seizures, feeding tubes, wheelchairs and death,” he said.

“Now her future is uncertain and we think that’s a great thing because of the potential.”

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