In light of previous laboratory studies of the antihistamine compound at UCSF, the researchers said, the drug most likely exerted its effect by repairing damage MS had inflicted on myelin, an insulating membrane that speeds transmission of electrical signals in the nervous system.
The drug tested in the trial, clemastine fumarate, was first identified as a candidate treatment for MS in 2013 by UCSF’s Jonah R. Chan, PhD, Debbie and Andy Rachleff Distinguished Professor of Neurology, vice chief of the Division of Neuroinflammation and Glial Biology, and senior author of the new study. First approved by the U.S. Food and Drug Administration (FDA) in 1977 for allergies, the drug has been available over the counter in generic form since 1993.
The researchers said that the Phase II results, published online on Oct. 10, 2017, in The Lancet, are the first in which a drug has been shown to reliably restore any brain function damaged by a neurological disease in human patients.
“To the best of our knowledge this is the first time a therapy has been able to reverse deficits caused by MS. It’s not a cure, but it’s a first step towards restoring brain function to the millions who are affected by this chronic, debilitating disease,” said the trial’s principal investigator, Ari Green, MD, also Debbie and Andy Rachleff Distinguished Professor of Neurology, chief of the Division of Neuroinflammation and Glial Biology, and medical director of the UCSF Multiple Sclerosis and Neuroinflammation Center.
Chan and Green are co-directors of the UCSF Small-Molecule Program for Remyelination, and both are members of the UCSF Weill Institute for Neurosciences.