it can happen - there is a list of 'requirements' to compare if you are actually going into a remission/dormancy after no activity. it can be found on the National MS Society site.. like they do for epileptics to get drivers licenses
DORMANT:
no relapses for this long_______
no active lesions for this long_______
no new problems
only your old problems, or less than
OR
if you just seem to be sliding downhill - SPMS

progressive multifocal leukoencephalopathy (PML) is not listed as a side effect for Aubagio (teriflunomide) in the manufacturer's package insert.
aubagio is a pill

Thank you for your answer. I feel definite negative changes in cognitive abilities, that SUCKS. I also feel minor physical changes, walking gets interesting, my hands shake more at times, but nothing major. I get nervous that any minute now something big will disrupt my life. It is scary b/c I lost my support person in 2020, I have to change meds b/c of scar tissue build up from years of Copaxone injections, My Neurologist said he feels Gilenya would be good for me. I am thinking about it but I feel like that and all pills put me at risk for PML since I am + JCV. I use to be so confident, now it is hard to make almost every decision due to fear. Today isn't great emotionally. But I will keep trying to improve or prevent deterioration as best I can. Hope your day is full of happy moments!

45 years for me. When I was first diagnosed my neurologist told me that I had a progressive MS and that it would be a slow continuous decline. And it has. I do have exacerbations from time to time which makes me hurt or exhausted all the time. I am actually having one right now. But even when I am not in an exacerbation I can tell I am feeling worse each day stretching into months and years. So yes, i think it is very possible to go into remission permanently but that is not the case for me. God bless you.

30 years for me