S1P signaling: new therapies and opportunities.

Development of sphingosine-1-phosphate receptor 1 (S1P1) modulators to dampen inflammation and its sequelae is becoming increasingly promising for treating medical conditions characterized by significant immunopathology. As shown by the non-selective S1P receptor modulator FTY720 (fingolimod [Gilenya(®)]) in the treatment of relapsing-remitting multiple sclerosis (MS), the ability to use S1P1 modulation to precisely block immune cell traffic-immunomodulation-while maintaining immunosurveillance, has opened therapeutic opportunities in various other immune-derived chronic pathologies, including inflammatory bowel disease (IBD), lupus, psoriasis, as well as, potentially, in early acute viral respiratory infection. Proof-of-concept studies across validated animal models with S1P receptor modulators highly selective for S1P1, such as BAF-312 (Siponimod), KRP-203, ONO-4641 (Ceralifimod), ponesimod and RPC-1063, and emerging clinical trials for safety and efficacy in humans, particularly in MS, ulcerative colitis (UC) and psoriasis, have set the stage for us to consider additional testing in various other autoimmune diseases.