Six-Year-Old Girl Who Died After Gene Therapy Treatment: Concealed Death Reveals Structural Flaws in the Scientific Community
Background
Gene editing technology, particularly base editing, which corrects single bases without causing double-strand breaks, has garnered attention as a new possibility for treating rare genetic diseases. In February 2025, a case in which a customized base editing therapy was successfully applied to KJ Muldoon, an infant with a life-threatening metabolic disease, at the Children's Hospital of Philadelphia (CHOP), was nominated as a candidate for the 2025 Science Magazine's Breakthrough of the Year.
However, this technology is not guaranteed to be safe for all patients. Gene therapy using adeno-associated virus (AAV) vectors carries the risk of serious side effects, such as immune reactions and liver toxicity, and can lead to unpredictable consequences, especially when large amounts of viral particles are injected into the central nervous system. An investigative report jointly published by Science and Retraction Watch on July 23, 2026, revealed a tragic case in which these risks became a reality.
Key Findings
On March 24, 2025, a six-year-old girl received base editing therapy at Xinhua Hospital in Shanghai, China. The girl had Snijders Blok-Campeau syndrome, a condition reported in only 237 cases worldwide, caused by a single base mutation (R1025W) in the CHD3 gene. Although her language and motor development were slower than her peers, her condition was not life-threatening.
The research team, led by Zilong Qiu, a neuroscientist at the Songjiang Institute of the School of Medicine at Shanghai Jiao Tong University, packaged base editors into a dual AAV vector and injected hundreds of millions of viral particles into the girl's spinal canal. Three days after the injection, she began to experience fever and kidney failure, and her platelet count dropped rapidly. Seven days later, on March 31, the girl died of thrombotic microangiopathy. The hospital's ethics committee concluded that the death was "definitely related" to the treatment.
The problem is that this death was concealed for more than a year. The ClinicalTrials.gov record was not updated, and there was no public announcement from the hospital, university, or researchers. Instead, the Qiu team published a paper in Nature in 2026, reporting successful base editing in a mouse model with the same mutation, without mentioning the human patient or her death, or the $860,000 (approximately $1.1 billion) that the girl's family paid for the research and development.
Warning signs were also evident in the preclinical animal data. Four experts reviewed the non-human primate experimental data and raised concerns about "obvious data manipulation or image correction." All four treated monkeys showed moderate to severe liver damage. Xinhua Hospital approved the procedure without even reviewing the final non-human primate safety report.
Significance and Prospects
This incident exposed four structural problems simultaneously. First, China's dual regulatory system allows hospitals to initiate clinical trials without prior approval from the National Medical Products Administration through the "hospital-led innovative treatment" clause. Second, there is an imbalance in the burden of cost. The girl's parents raised $860,000 from relatives, which raises questions about the ethics and exploitation of this research funding model. Third, there is a failure in the transparency of scientific publishing. The fatal outcome was concealed, and only the related animal experimental data was published in Nature. Fourth, there is a tension between the urgency of treating rare diseases and the need for rigorous oversight.
Gemma Marfany, a geneticist at the University of Barcelona, described this case as "medical malpractice caused by the competition to be the first," and pointed out that it violated all four principles of bioethics: non-maleficence, beneficence, autonomy, and justice. Steven Gray, from the University of Texas Southwestern Medical Center, stated, "This should not have been allowed to proceed to clinical trials."
The girl's father said in the investigative report, "After realizing that these safeguards were missing, my perspective on the entire project has fundamentally changed." The family has requested that the Nature paper be retracted.
Girl’s death in China raises questions about the safety and cost of gene therapy, China’s biotech push, and scientific publishing practices
This incident can directly impact the regulatory framework for personalized gene therapy (N-of-1 therapy), which is expanding globally. The U.S. FDA operates an expanded access pathway for individual patient-specific treatments, but it requires animal experimental safety data and independent review. China's hospital-led innovative treatment clause allows procedures to be performed without these safeguards, demonstrating that the oversight gap has not been closed even after the He Jiankui CRISPR baby incident in 2018.
From the perspective of pharmaceutical and biotechnology companies, this incident serves as a warning. The immunogenicity and hepatotoxicity of AAV vector-based gene therapy are key hurdles in clinical development, and proceeding to human administration despite the identification of liver damage in the non-human primate stage represents a failure to meet even the minimum standards for translational research. In the future, independent verification of preclinical data, mandatory reporting of adverse events, and ethical review of the financial burden on patient families will be inevitable in the field of gene therapy for rare diseases.