We and others have made the case that certain viruses are important in the pathogenesis of MS. Now I have no problem with this, but how do you show this and what do you do about it?
A case has been made that some MS drugs have anti-viral activity, indeed interferons interfere with viral replication. So drugs deplete the cells where the EBV virus hides/ So is it anti-viral.
But then we have teriflunomide. In the paper the prof-Gs make the case that it is anti-viral. It is anti-proliferative and so should inhibit viral replication as these replicate as the cell divides. However, you can’t have it both ways and if teriflunomide is great at inhibition of EBV and EBV is so important in MS….why isn’t teriflunomide that potent compared to other treatments?
If the anti-viral effect is key, maybe it is not that good as an anti-viral. You can’t have it both ways.
I believe that teriflunomide is not a cure….so what should we expect if we target EBV in MS? We already can see that anti-EBV T cell therapy is not a cure, based on the data presented so far. Is EBV really the important thing to target during MS.
I could easily argue that the effect of EBV has happened a long time before you get diagnosed then it should not do anything. Remember people seem to get infected with EBV long before MS gets diagnosed, so I would argue that targeting EBV in MS is maybe too late. Time will tell
Gold et al. Effect of teriflunomide on Epstein–Barr virus shedding in relapsing-remitting multiple sclerosis patients: Outcomes from a real-world pilot cohort study
Background: Given its potential antiviral activity, we investigated the effect of teriflunomide on EBV in patients with relapsing-remitting MS (RRMS).
Methods:Saliva samples were collected at home and analysed for EBV DNA presence in patients with RRMS treated with teriflunomide for ≥3 months.
Results: : The proportion of patients with detectable EBV in the teriflunomide cohort was lower than in the reference cohorts. The proportion of samples with EBV DNA or shedding from teriflunomide-treated patients was reduced relative to each reference cohort (P<0.0001; >5.8 virus copies/µL cut-off).
Conclusion:This pilot study demonstrated the feasibility of at-home saliva sample collection and revealed a possible effect of teriflunomide on EBV shedding.