FDA approves $4 million gene therapy for rare childhood disease
The treatment, funded partly by a viral video campaign led by one family, was cleared in September for Sanfilippo syndrome.
By Yasmin Duda ·
The Food and Drug Administration approved a one-time gene therapy infusion called Fayuvi in September. The drug treats Sanfilippo syndrome, a rare inherited disorder that causes severe developmental decline in children. Ultragenyx, the biotech company that markets the treatment, priced it at nearly $4 million. That figure ties it for the second most expensive gene therapy on the market, according to drug price research firm 46brooklyn.
Sanfilippo syndrome results from a faulty gene that prevents the body from breaking down heparin sulfate. As the molecule accumulates, it damages cells, leading to seizures and the loss of speech and motor skills. According to the Cure Sanfilippo Foundation, patients typically do not live past their teenage years. The disease was diagnosed in Eliza O'Neill when she was three years old in 2013. Her mother, pediatrician Cara O'Neill, noted that Eliza had learned many words but did not use them in typical social situations before the positive metabolic test results.
Research on a potential cure began in the late 1990s at Nationwide Children's Hospital in Columbus, Ohio. Haiyan Fu developed a therapy using a modified virus to deliver a working copy of the broken gene. Fu faced funding challenges in 2009 and considered stopping her work. Eight patient foundations, including Ben's Dream and a Cure for Kirby, stepped in to provide financial support to keep the research going.
Glenn O'Neill, Eliza's father, sought additional funding for the first human trial in 2014. He contacted filmmaker Benjamin Von Wong to create a viral video. The resulting campaign, titled Saving Eliza, broke GoFundMe's record at the time. It raised $1 million in a few weeks and eventually reached $2 million. The funds helped launch the first human trial in May 2016.
Eliza O'Neill became the first patient to receive the therapy during that trial. She was six years old at the time and had already lost the ability to speak. While her speech did not return, she now communicates using picture cards and devices. She attends school and learned to float on a pool noodle during the summer of 2026.
Ultragenyx acquired the rights to the therapy in 2022 after observing promising trial results. CEO Emil Kakkis stated that the treatment works best when administered to younger children. He noted that patients treated at six months of age have shown strong outcomes. Kakkis added that the company aims to ensure all patients receive the infusion regardless of logistical barriers or cost.
Haiyan Fu received a call from Cara O'Neill immediately after the FDA approval was announced. Fu said the approval brings mixed emotions because the process took many years. She stated that it should not take this long to bring a life-saving treatment to patients.
Source: NPR
