Can a drug for EBV change the landscape for treating MS?
The Epstein-Barr virus (EBV) is a highly contagious type of herpes that spreads through saliva, with approximately 90% of adults having been exposed to it. It can cause mononucleosis, or mono, especially when contracted during adolescence or young adulthood which, in the general population, presents harmless or mild symptoms.
For many years, researchers suspected multiple sclerosis (MS) to be a rare complication of infection with EBV.
A recent longitudinal study following more than 10 million young adults over 20 years found that EBV infection could be a significant environmental factor for those who had signs of nerve damage, several years prior to MS onset.
A growing body of evidence suggests that chronic EBV infection of B cells, a type of immune cell, might be a driver of chronic symptoms in MS, such as fatigue.
Understanding the link between EBV and MS has led to multiple ways of targeting EBV with antiviral medications, vaccines and cell therapies.
Antiviral drugs work by preventing viruses from making copies of themselves (replicating). Although, antivirals don’t completely eliminate the virus from the body, there is hope that using them to stop EBV replicating can help suppress MS activity.
Despite EBV being a common virus, there are currently no approved antiviral treatments for EBV infection in Australia. Development of new drugs is an expensive and long process. A faster alternative is to “repurpose” drugs already approved for other uses and test them for other conditions.
A new Australian study took a systematic approach in selecting 11 approved drugs with the potential to treat EBV in MS for clinical trials in Australia.
In this study, an expert scientific panel assessed each drug for potential effectiveness in treating MS and possible side effects.
Information on potential side effects of the drugs, as well as how they are taken, was reviewed by people living with MS. This expert lived experience panel scored each drug by answering whether they would consider participating in clinical trials for three different purposes in MS: treating disease activity in very early MS, treating fatigue or treating MS progression.
Both panels scored the drugs with six of 11 drugs yielding the same highest score. A further review by the scientific panel shortlisted four drugs, deemed to have the best balance of effectiveness, safety and being well-tolerated for use in MS.
Two Phase III clinical trials of repurposing these antiviral drugs for EBV in MS, known as STOP-MS and FIRMS-EBV, is expected to commence recruitment in Australia in the first half of 2025.
These will help to answer whether antivirals are effective in suppressing EBV infection in people with MS, and whether they are effective in treating progression or fatigue in MS.
Funded by the Australian Federal Government’s Medical Research Future Fund (MRFF), and supported by MS Australia, these clinical trials have the potential to revolutionise therapy for the majority of people with MS.
Adapted from Could drugs that target EBV treat MS? - MS Australia
