The U.S. Food and Drug Administration approved Fayuvi in September, marking a milestone for families affected by Sanfilippo syndrome. This one-time infusion is designed to treat a rare inherited metabolic disorder that causes severe neurological decline in children.
Sanfilippo syndrome is caused by a faulty gene that prevents the body from breaking down heparin sulfate. As this molecule builds up in cells, it leads to the loss of speech and walking ability, seizures, and a shortened lifespan. Most children with the condition do not live past their teens.
The path to approval began decades ago with researcher Haiyan Fu at Nationwide Children’s Hospital in Columbus, Ohio. Fu started working on a gene therapy for the disease in the late 1990s. Her approach used a modified virus to deliver a working copy of the broken gene to patients’ cells. She believed early treatment could potentially cure the disease, but funding the research became a major hurdle.
Family fundraising drives research
Fu nearly quit the project in 2009 due to lack of funds. Patient advocacy groups stepped in to keep the work alive. Eight foundations, including Ben’s Dream and a Cure for Kirby, provided financial support until the research was ready for human trials.
Glenn and Cara O’Neill, parents of Eliza O’Neill, played a pivotal role in raising capital for the first clinical trial. Eliza was diagnosed with Sanfilippo syndrome in 2013 after showing developmental delays. Her parents launched a crowdfunding campaign that resulted in a viral video created by filmmaker Benjamin Von Wong in 2014.
The Saving Eliza video broke GoFundMe records at the time. The campaign raised $2 million in just a few weeks. This money helped fund the first human trial, which began in May 2016. Eliza became the first person to receive the experimental therapy.
Ultragenyx acquires rights and sets price
The promising results from early trials attracted the biotech industry. Ultragenyx acquired the rights to the gene therapy in 2022 and continued studies. The company submitted data to the FDA for review, leading to the September approval.
Ultragenyx CEO Emil Kakkis stated that the treatment works best when administered to very young children. He noted that brain damage accumulates quickly, so patients diagnosed at age 2, 3, or 4 have already lost significant ground. The company reported that children treated at around 6 months of age have shown strong results.
The price for the one-time infusion is set at nearly $4 million. This figure ties the therapy for the second most expensive gene therapy ever recorded, according to drug price research firm 46brooklyn. Kakkis said the company is committed to ensuring every patient can access the treatment regardless of the cost or location.
For Haiyan Fu, the approval brings mixed emotions. She received a call from Cara O’Neill moments after the announcement. Fu expressed that while the news is positive, the long road to approval is frustrating for families who have already lost children to the disease.
Eliza O’Neill is now almost 17 years old. She was 6 when she received the therapy in 2016. By that time, she had already lost her ability to speak, which has not returned. She now communicates using picture cards and devices. She attends school and recently learned to swim with a pool noodle. Her father, Glenn, said he feels proud of her resilience despite the difficult journey.
Source: NPR
