What happened in the China case
A six-year-old girl in China, who had Snijders Blok-Campeau syndrome caused by a CHD3 gene mutation, died in March 2025 after receiving a base-editing therapy aimed at the brain. Base editing is described as changing specific DNA letters without cutting both DNA strands.
The child’s parents pursued the therapy after learning about research led by neuroscientist Zilong Qiu at Shanghai Jiao Tong University. The therapy required delivering gene-editing machinery into brain tissue using high doses of adeno-associated viruses (AAVs), which can trigger serious immune reactions, according to the reported account.
The reported account says the family helped fund much of the therapy’s development, contributing about $860,000 using personal funds and borrowed money.
The reported account describes the clinical trial as an investigator-initiated trial at Xinhua Hospital and says it proceeded without prior review by China’s national drug regulator, the National Medical Products Administration (NMPA). Independent experts cited in the account raised questions about whether animal toxicology and other preclinical safety data justified moving to human dosing. The account states that monkey studies reported liver injury in all treated animals and kidney damage in at least one.
The reported account states the therapy was injected into the child’s cerebrospinal fluid on March 24, 2025. Soon after the injection, the child developed fever and kidney damage and died about a week later.