AMSTERDAM, NETHERLANDS / RankWire.AI / – A medication traditionally used to treat high blood pressure has demonstrated promise in slowing the progression of vanishing white matter disease in pediatric patients. Researchers at Amsterdam UMC conducted a trial involving 33 children diagnosed with this rare inherited neurological condition. They compared their outcomes to 66 closely matched patients from an international historical registry. The findings indicated that treatment was associated with a reduced risk of losing the ability to walk with support. The phase 1/2 results were published in The Lancet Neurology in August 2026.
Vanishing white matter disease, also known as VWM, impacts the brain’s white matter and typically manifests during childhood. Diagnosis for the children enrolled in the study was confirmed through genetic testing and magnetic resonance imaging. All participants had developed symptoms by age six and had been living with the disease for no more than eight years. Prior to entering the trial, each child could walk at least 10 steps with some assistance. Eligible patients were enrolled from May 2021 through May 2024.
The primary focus of the analysis was to evaluate how long children retained the ability to walk with support. Researchers matched each treated patient with two historical controls who did not receive treatment, based on disease onset and level of disability. The hazard ratio for reaching the main walking endpoint was 0.33, indicating a 67% lower estimated hazard for children treated with guanabenz. Brain imaging also revealed less white matter deterioration among treated children, with some showing no progression during follow-up.
Study Monitors Walking Capacity and Brain Changes
Participants took guanabenz orally, starting at 0.15 milligrams per kilogram of body weight daily. Doses were gradually increased over approximately six weeks based on individual tolerance. The trial identified 2 milligrams per kilogram per day as the optimal dose. Of the 33 children enrolled, 31 completed the study, with a median treatment duration of 3.1 years. The strongest effects appeared in children whose symptoms began at age three or later.
During safety assessments, investigators documented 63 serious adverse events affecting 25 participants. Of these, 30 events were considered likely or very likely related to guanabenz. Hallucinations were reported in 18 children, mainly during the first four months of treatment. Three children experienced severe constipation, and one had a temporary episode of low blood pressure with sedation. All four cases required brief hospital stays but later resolved. No participants discontinued treatment due to side effects, and no deaths occurred during the trial.
Extended Follow-Up Research Continues Post Phase 1/2
Because the study did not randomly assign children to treatment or control groups, researchers compared the guanabenz group to historical cases from the Vanishing White Matter Registry. This design meant that no untreated control group was enrolled concurrently. Researchers believe that longer-term follow-up will be necessary to confirm the drug’s potential as a disease-modifying therapy. Currently, guanabenz cannot cure VWM, and it has not received regulatory approval for this indication.
Amsterdam UMC is conducting ongoing follow-up studies involving children from the original cohort. These studies will assess walking ability, neurological function, brain imaging, safety, and different dosing regimens over an extended period. At present, guanabenz remains available for VWM only within a research context. Originally developed for hypertension, the drug influences cellular stress pathways linked to the disease. The recent findings offer valuable clinical data on treatment effects in children with early-onset vanishing white matter disease.