An experimental drug reversed paralysis and vision loss in a mouse model of MS, while preserving nerve fibres and their myelin insulation, researchers found.
Kamuvudine K-9 also stopped levels of neurofilament light chain, a blood marker of nerve damage, from rising during the experiments.
Animals given an approved MS treatment did not recover nearly as much neurological function as those treated with K-9.
The drug was developed by Jayakrishna Ambati, founding director of UVA’s Center for Advanced Vision Science and DuPont Guerry III Professor in the UVA School of Medicine’s Department of Ophthalmology.
K-9 is derived from nucleoside/nucleotide reverse transcriptase inhibitors, or NRTIs, a class of HIV drugs already approved for use in people.
Ambati said: “Most MS therapies are aimed at preventing the next attack.
“What’s remarkable is that K-9 not only prevented further neurological deterioration, but animals recovered function they had already lost.
“When that recovery is considered together with the preservation of nerve tissue, the NfL response and the human epidemiologic findings, we believe there is a compelling rationale to test this approach in patients.”
The researchers also analysed health insurance data from more than three million people to examine the relationship between NRTI use and MS.
They found NRTI use was associated with a 41 per cent lower risk of developing MS and a 36 per cent reduction in the annual relapse rate among people with MS.
MS is an autoimmune neurological condition in which the immune system is thought to attack myelin, the protective covering around nerves.
Damage to myelin can disrupt communication between the brain and the rest of the body, contributing to symptoms including vision loss, fatigue, weakness and difficulty moving.
Existing MS medicines can slow disease progression and reduce relapses, but there is currently no cure.
Ambati previously found that NRTIs can block inflammasome activation, an inflammatory process involving part of the immune system.
This led to the development of K-9 as an alternative to NRTIs that appears safer and more effective.
K-9 has already entered clinical trials for diabetic macular oedema and thyroid eye disease.
The researchers stressed that K-9 remains experimental for MS and that controlled clinical trials will be needed to determine whether the functional recovery seen in mice can also occur in people.
They hope the work will also inform studies of other neurodegenerative conditions involving inflammasome activation and damage to nerve fibres, including amyotrophic lateral sclerosis, in which K-9 is slated to be tested.
“Inflammasome inhibition is now recognised as the cutting edge of therapies for multiple inflammatory diseases,” Ambati said.
“K-9 and the related K-8, which has already shown remarkable efficacy in macular degeneration, could also be beneficial in other diseases such as Alzheimer’s disease and Parkinson’s disease.”
