The first safety and efficacy data for the use of vafidemstat in relapse-remitting and secondary progressive MS (SATEEN; EUDRACT No 2017-002838-23) indicate that long-term vafidemstat treatment was safe and well tolerated and modulated the Th1/Th2 cytokines including a dose dependent decrease of IFNγ/IL4 ratio [95]. This evidence concerns the gene IL4 and secondary progressive multiple sclerosis.