Gene Therapy: One Family's Funding Effort Led to FDA Approval

Eliza O'Neill’s family turned to the internet in 2014 to fund a medical breakthrough that had stalled for years. The O'Neills, parents of a child diagnosed with Sanfilippo syndrome, raised enough money to keep a gene therapy trial alive. That financial push eventually led to the Food and Drug Administration approving the treatment, known as Fayuvi, in September.

Eliza was three years old when her parents noticed she was falling behind on developmental milestones. Her mother, Cara O'Neill, a pediatrician in Columbia, S.C., noted that while Eliza knew many words, she did not use them in typical social situations. In 2013, a colleague suggested testing for metabolic disorders. The results confirmed Sanfilippo syndrome, a rare inherited disease caused by a faulty gene that prevents the body from breaking down heparin sulfate. As this molecule builds up, it causes severe complications, including seizures and the loss of the ability to speak and walk.

Researchers at Nationwide Children’s Hospital in Columbus, Ohio, had been working on a gene therapy for Sanfilippo since the late 1990s. Haiyan Fu, the lead researcher, used a modified virus to deliver a working copy of the broken gene to cells. By 2009, Fu feared she would have to quit the project due to a lack of funding. However, families of children with the condition intervened. They told Fu they could not let her leave and offered to provide some of the funds to keep the work going.

Eight patient foundations, including Ben's Dream and a Cure for Kirby, helped sustain the research until it was ready for human trials. Glenn O'Neill, Eliza’s father, proposed a method to raise the substantial capital needed for the clinical trial. He contacted filmmaker Benjamin Von Wong to create a viral video. The resulting video, titled Saving Eliza, was released in the spring of 2014. It helped the O'Neills break the GoFundMe record at the time, raising $1 million in a few weeks and eventually reaching $2 million.

The funds supported the first human trial, which began in May 2016. Eliza became the first patient to receive the therapy. By 2022, biotech company Ultragenyx acquired the rights to the gene therapy and continued its study. The company submitted data to the FDA for review, leading to the approval of Fayuvi. Ultragenyx CEO Emil Kakkis stated that the treatment works best when administered to younger children because more brain tissue remains. He noted that patients treated at six months of age have shown strong results, whereas children diagnosed at two to four years old have already lost significant ground.

Ultragenyx set the price for the one-time infusion at nearly $4 million. According to drug price research firm 46brooklyn, this ties it for the second most expensive gene therapy ever. Kakkis said the company is committed to treating every patient regardless of cost or location. He emphasized that no logistical rules should stop a patient from receiving the treatment.

Fu received a call from Cara O'Neill moments after the FDA approval was announced. She also received messages from other families who had funded her research, some of whom had lost children during the process. Fu described the approval as mixed emotions, noting that it should not have taken this long for the therapy to reach patients.

Eliza is now almost 17. She was treated at age six, after she had already lost her ability to speak. The speech did not return, but she now communicates using picture cards and devices. She attends school and spent the summer learning to float on a pool noodle. Glenn O'Neill said he feels proud of his daughter, acknowledging the difficult path they have traveled but recognizing her good fortune.