S1PR1 and myeloid sarcoma: Fingolimod is approved for the treatment of MSbased on its mechanismof action: modulation of the sphingosine-1-phosphate receptor (S1P).Additionally, two more drugs, namely, siponimod, and ponesimod (Figure ), chemically diverse to fingolimod but withdocumented efficiency against S1P, have been also recently approvedfor MS clinical treatment.