As reported by NewsWise, new clinical study led by investigators at the University of North Carolina at Chapel Hill is offering rare hope for families affected by Hunter syndrome, a devastating genetic condition that causes progressive physical and neurological decline. Findings published in the New England Journal of Medicine highlight early evidence that an experimental treatment may be able to reach the brain—something current therapies cannot do.
Hunter syndrome, or Mucopolysaccharidosis II (MPS II), results from the absence of an enzyme required to break down certain cellular waste products. Without treatment, these substances accumulate throughout the body and central nervous system, leading to organ dysfunction, cognitive deterioration, and often death during adolescence. Existing enzyme replacement therapies improve some physical symptoms but cannot cross the blood–brain barrier, leaving neurological complications untreated.
The newly reported research centers on an investigational therapy developed by Denali Therapeutics and evaluated under the leadership of Joseph Muenzer, MD, PhD, Director of the Muenzer MPS Research and Treatment Center at UNC. The drug, tividenofusp alfa, uses Denali’s TransportVehicle™ platform—an approach designed to ferry therapeutic enzymes into the brain by engaging natural receptor pathways.
In trial participants, the therapy significantly lowered levels of heparan sulfate, a sugar molecule whose accumulation drives neurological injury in severe MPS II. Dr. Muenzer emphasized the magnitude of the unmet clinical need, noting that the decline in cognition, language, mobility, and hearing profoundly affects both individuals and their families. He expressed optimism that a therapy capable of addressing neurological symptoms could reshape the future for patients.
For Kim Stephens, DBA—Executive Director of the Muenzer MPS Center and mother of a son living with MPS II—the research carries deep personal meaning. She described the heartbreak of watching her son Cole gradually lose the ability to speak, recalling that his final word was “Mommy.” The prospect of a therapy that reaches the brain, she said, offers hope that other families may be spared similar losses.
Stephens relocated to Chapel Hill three years ago to help lead the center, which blends clinical care, education, advocacy, and research in a comprehensive model for rare disease support. The Muenzer Center itself reflects decades of scientific dedication: Dr. Muenzer created the first MPS II mouse model at UNC more than two decades ago, and Denali relied on this model to demonstrate the experimental therapy’s ability to cross the blood–brain barrier during preclinical testing.
The establishment of the center, made possible through philanthropic support from Vaughn and Nancy Bryson, marks a milestone in MPS research and patient care—one Dr. Muenzer describes as a long‑held vision. He noted that the center aims not only to advance therapeutic discovery but also to improve quality of life for those living with MPS through expert, coordinated care.
As research progresses, UNC’s work represents a significant step toward what could become the first enzyme replacement therapy capable of directly treating the neurological effects of Hunter syndrome—an advance that would dramatically alter the landscape for this ultra‑rare condition.
