Personalized gene therapy gives hope to families of kids with a rare form of epilepsy
Mutations in the gene that controls the flow of sodium ions into neurons can cause a rare and severe form of childhood epilepsy that can’t be controlled by traditional anti-seizure medications.
Kids who develop the condition, officially called SCN2A-related developmental epileptic encephalopathy, face a lifetime of complications, including developmental delays, autism, movement problems and gastrointestinal issues.
However, a promising new gene therapy treatment is inspiring hope. A team of researchers led by Rady Children’s Institute for Genomic Medicine and UC San Diego spent two years treating two patients with the condition with gene therapy tailored to each child’s specific gene mutation.
Both showed a dramatic drop in seizure frequency, plus developmental gains, with minimal side effects. The studies were published July 21, 2026, in the medical journal Nature Medicine.
“The therapy is deliberately designed to target the individual’s genetic diagnosis,” says principal investigator Olivia Kim-McManus, MD, director of the Rady Precision Therapeutics Neuro-Interventional Program at Rady Children’s Hospital San Diego, clinical investigator and physician-scientist at Rady Children’s Institute for Genomic Medicine and an associate professor of neurosciences at UC San Diego School of Medicine. “We’ve seen changes across the board, showing that targeting the root genetic cause can produce measurable improvement.”
While both patients showed notable improvements, Connor Dalby, who was 14 at the time the study began, had results that were extraordinary. He experienced a 90% reduction in seizure frequency, eventually reaching stretches of seizure-free days, plus he experienced improvements in language and motor skills, sensory processing and adaptive behaviors, and chronic gastrointestinal issues. At age 15, Connor walked unassisted for the first time.
“Since then, he’s been walking independently,” says Dr. Kim-Manus. “When we really think about precision therapy in a personalized way, you can’t get more personalized than that.”
Connor’s mom, Kelley Del Real, says that her son had tried more than a dozen different anti-seizure medications prior to this clinical trial, and none had a significant impact.
“It’s totally changed our quality of life,” she says.
However, since the therapy affects gene expression but doesn’t permanently change the underlying genetic code, results were temporary. To sustain the improvements, the medication would have to be regularly administered via injection into spinal fluid under anesthesia.
WE’VE SEEN CHANGES ACROSS THE BOARD, SHOWING THAT TARGETING THE ROOT GENETIC CAUSE CAN PRODUCE MEASURABLE IMPROVEMENT.
The therapy’s early successes give researchers hope that similar medications can be scaled to treat greater numbers of patients with similar genetic backgrounds. Dr. Kim-Manus says that while these therapies are still investigational, they provide a model for rapidly translating personalized genetics into treatments, potentially accelerating development for many other diseases caused by single gene mutations.
“It’s like a sci-fi, Star Trek idea, and that’s the look that I used to get when I was just starting this. But now that we’re on the other side showing safety and efficacy, the idea is spreading beyond academia to the pharma and biotech industry and having a big impact,” she says.