Sphingosine 1 phosphate receptor (S1PR) is a member of the G protein-coupled receptor (GPCR) family, which is mainly coupled with the G protein α subtype. Numerous studies in recent years have yielded a variety of drugs that are capable of selectively inhibiting or stimulating S1PR to vary degrees. In 2010, the US FDA approved the drug Gilenya (FTY720) for the treatment of multiple sclerosis. This sphingolipid analog, as a prodrug, is rapidly phosphorylated into a biologically active form by the action of the enzyme. Phosphorylated Gilenya is a potential agonist of S1PR. The structural modification of Gilenya resulted in a new selective S1PR prodrug agonist SYL978, which showed significant agonistic activity on the S1PR in vitro.
