WHY most (but perhaps not all) DMARDs work equally well

Biological- or targeted-synthetic DMARD-responses reported in randomized clinical trials, placebo-controlled or head-to-head, in patients with rheumatoid arthritis, psoriatic arthritis or spondyloarthritis are unbelievably similar, when looking across trials performed in the same disease and applying the same primary outcome measures. The exception to this rule may be the response to Janus-kinase-inhibitors, which seem to work 10 % better in all trials (JAK-bonus) This article provides a potential explanation for this remarkable phenomenon, including an explanation for the JAK-bonus. It seems as if JAK-inhibitors exert some inflammation-independent effects on pain, fatigue and wellbeing, and that drug treatment of rheumatic diseases is more than the inhibition of inflammation alone.