In a groundbreaking achievement, an infant with a severe genetic liver disease, carbamoyl phosphate synthetase 1 (CPS1) deficiency, has been successfully treated with personalized CRISPR gene editing therapy. This marks the first time this technology has been successfully deployed to treat a human patient.
The infant, known as K.J., received the customized therapy developed by researchers at the Children's Hospital of Philadelphia (CHOP) and the University of Pennsylvania. The therapy targeted and corrected the specific genetic mutation in K.J.'s liver cells responsible for the CPS1 deficiency. The treatment, named “k-abe,” combines a guide RNA (“kayjayguran”) and a custom mRNA encoding an adenine base editor.
Administered at six to seven months old, K.J. has shown remarkable improvement, tolerating increased dietary protein and requiring less medication. As of April 2025, K.J. had received three doses of the therapy with no serious side effects. This pioneering success offers hope for treating other rare genetic disorders with personalized gene editing therapies. The study was published in The New England Journal of Medicine on May 15, 2025.