SR-4370 is primarily used in research settings as a selective agonist for the S1P1 (sphingosine-1-phosphate receptor 1). It plays a key role in immunomodulation by promoting the internalization of S1P1 receptors on lymphocytes, which inhibits their egress from lymph nodes. This mechanism leads to a reduction in circulating lymphocytes, making SR-4370 valuable in studying autoimmune disease models such as multiple sclerosis and rheumatoid arthritis. Due to its potent and selective action, it is also employed in pharmacokinetic and pharmacodynamic studies to evaluate receptor modulation and immune cell trafficking. Its use remains restricted to preclinical research, where it helps in understanding sphingolipid signaling pathways and developing novel immunosuppressive therapies.