The blood pressure medication guanabenz can slow or halt the progression of vanishing white matter, a rare hereditary brain disease, according to research from the Emma Children’s Hospital at Amsterdam UMC. The condition primarily strikes children ages 1 to 6. The disease is extremely rare, with an estimated 1 in 100,000 children born with it worldwide.

Vanishing white matter, or VWM, causes the white matter in the brain to disappear. White matter carries signals between different brain regions.

It stems from a defect in the body’s response to stress factors such as fever or viruses. In children with VWM, that stress response remains constantly active even without a trigger. Patients typically progress to needing a wheelchair, have difficulty speaking, or require a feeding tube to eat.

Guanabenz appears to dampen this stress response, the study found. During the research, children treated with guanabenz reached the point of needing a wheelchair less quickly or less often. None of the treated children died during the study period, while five children in the comparison group did. MRI scans also showed that white matter deteriorated more slowly in those who received guanabenz.

Researchers gave the drug to 33 children from multiple countries and tracked them for four years. They compared the children’s disease course with a group of 66 earlier patients who did not receive the medication.

The researchers stressed that guanabenz does not cure the disease. The benefit disappears if treatment stops.

The comparison group was not a simultaneous control group, meaning the study lacked a concurrent set of children who did not receive the drug.

“But this research certainly marks a turning point,” Marjo van der Knaap, professor of pediatric neurology, told NU.nl