any info about using cobimetinib, an IL-6 inhibitor, for PMR?

[benhemp]

I've been reading the posts on this forum about Actemra (tocilizumab) and suppression of IL-6, the cytokine causing the negative symptoms of PMR. Searching the web led me to a scientific conjecture from 2018 that combimetinib may be useful for treating PMR. Has anyone heard anything further about this? Here is the link:

ard.bmj.com/content/78/7/e70

[PMRpro Ambassador]

PMR is not the disease - it is the outward manifestation of an underlying condition. Polymyalgia rhematica just means many painful muscles. We talk about a form with no as yet identified mechanism and where the other potential easily identifiable causes should have been ruled out. IL-6 is one of the mechanisms that has been identified as a possible cause since an inhibitor has lead to clinical improvement in both GCA and PMR.

This paper is about a very specific cause of the PMR-like symptoms and it was drug induced. That doesn't mean that MEK 1/2 is involved in all PMR cases, any more than all PMR cases are due to an underlying cancer which is another potential diagnosis. It is more a comment "is this a potential mechanism" - and it is likely to be a long time before more work shows a link and the finnace is available for clinical trials. Even studies with funding that had started have been delayed because of Covid.