Hidden death exposed by joint investigation
A 6-year-old girl identified only as Mei died seven days after receiving an experimental gene therapy at Xinhua Hospital in Shanghai in March 2025. Her death was never publicly disclosed by the scientists who developed the treatment. Now, more than a year later, a joint investigation by Science and Retraction Watch has brought the case to light. Mei's parents are telling her story in the hope that other families will be spared the same tragedy.
Mei had Snijders Blok-Campeau syndrome, a rare genetic disorder caused by mutations in the CHD3 gene. The condition affects brain development and can cause speech problems and intellectual disability, but people with the condition typically have normal life expectancy. Mei's case was considered mild.
CRISPR therapy bypassed proper safety review
The therapy was developed by Dr. Zilong Qiu, a neuroscientist at Shanghai Jiao Tong University who also runs a gene-therapy company called Lanqi Xintu Gene Technology. Qiu used a CRISPR-based base editor delivered by modified viruses injected into Mei's spinal fluid. Hundreds of trillions of viruses were needed to deliver a sufficient dose to the brain.
Toxicology studies in monkeys had shown moderate to severe liver damage in four animals and kidney damage in one — warning signs that the therapy was triggering a dangerous inflammatory response. But the hospital's ethics committee did not review this data before approving Mei's procedure. Under China's regulatory system, the trial did not need clearance from the country's equivalent of the FDA.
Family paid $860,000 for unproven treatment
Mei's parents paid approximately $860,000 toward the cost of developing, testing, and deploying the therapy, including informal payments to research team members. Charging for an unproven therapy is illegal under Chinese law. The hospital was later fined the equivalent of about $3,600 for failing to properly oversee the trial. Mei died from thrombotic microangiopathy, an immune reaction that causes blood clots and is a known risk of virus-based gene therapies.