Significant Advancements in Batten Disease Treatment Using Zebronkysen

In June 2025, a notable milestone was reached in the treatment of Batten disease, as Amelia and Makenzie Kahn celebrated one year since receiving their first dose of Zebronkysen. This personalized treatment, developed by Dr. Michelle Hastings and her team at the University of Michigan, targets a specific mutation associated with juvenile Batten disease, clinically known as CLN3. The innovative therapy has shown remarkable benefits for the Kahn sisters, who suffer from this rare and fatal neurodegenerative disorder.

Batten disease leads to severe neurological decline and significantly impacts the quality of life of affected children. Symptoms typically include loss of motor skills, cognitive decline, vision loss, and seizures. Most patients with Batten disease have a life expectancy that rarely extends beyond their teenage years. According to the Batten Disease Support and Research Association, the urgency for effective treatments has prompted extensive research into potential therapies.

The ForeBatten Foundation, a nonprofit organization founded in 2017, has been instrumental in funding research and providing support for families affected by Batten disease. In June 2024, the foundation launched an unprecedented clinical trial, the “N-of-2” study, which represents a new model in personalized medicine. Dr. Yael Shiloh-Malawsky, a professor of neurology at the University of North Carolina (UNC) School of Medicine, leads this groundbreaking clinical trial. Unlike traditional clinical trials that involve larger groups, the N-of-2 study focuses on two patients, in this case, Amelia and Makenzie.

The clinical trial has yielded promising results after the first year of treatment. For example, Makenzie has shown significant improvements in her mobility, going from walking only 22 yards without assistance to 48 yards after six months of treatment. In addition, her dystonia symptoms, which include involuntary muscle contractions and pain, have markedly decreased, allowing her to regain previously lost abilities, such as getting out of bed without help. Her mother, Karen Kahn, noted, “Makenzie used to nap a lot and be sleepy. Now, she's more alert and awake.” These changes are not just anecdotal; they have been carefully documented throughout the trial.

Amelia's condition has also improved. Following the treatment, she has begun to tolerate sensory inputs better and has regained the ability to eat and drink independently. Previously reliant on oxygen for sleep, her requirement has significantly decreased. Karen Kahn expressed relief at the reduction of rescue medications needed to manage Amelia’s anxiety and muscle spasms, stating, “We rarely need them now, which is a huge deal.”

Dr. Shiloh-Malawsky remarked, “Our hypothesis was that restoring CLN3 protein function would stabilize this neurodegenerative disorder and prevent further decline. We did not expect to see improvement in addition to a slowing of decline; seeing improvements is more than we hoped for.” These findings highlight the potential of Zebronkysen to not only slow the progression of Batten disease but also to enhance the quality of life for patients.

The administration of Zebronkysen has followed a structured regimen, starting with an intrathecal injection of 15 milligrams, and subsequently increasing the dosage with each treatment cycle. As of June 2025, the girls received a targeted high dose of 45 milligrams, which researchers hope will lead to sustained benefits. The study team is optimistic that continued treatment will yield further improvements and stabilize the girls’ conditions.

The implications of this research extend beyond just the Kahn sisters. The ForeBatten Foundation and the Vanguard Clinical Rare Disease Foundation (VCRDF) are actively seeking funding to develop treatments for other mutations associated with CLN3 Batten disease, potentially benefiting a larger patient population. Dr. Shiloh-Malawsky emphasized the urgency of this endeavor, stating, “Seeing the beneficial results from this trial puts an emphasis on the urgent need to develop similar interventions for people with other mutations in this gene of Batten disease.”

As researchers continue to explore individualized investigational antisense oligonucleotides (ASOs) and other innovative therapies, the prospects for treating various mutations of Batten disease appear increasingly promising. The Kahn family’s journey underscores the potential of personalized medicine to transform outcomes for rare diseases, offering hope to families facing similar challenges. With continued research and support, the future of Batten disease treatment may be on the brink of a significant breakthrough.