Etrasimod: First Approval.

Etrasimod (VELSIPITY™) is an orally available, small-molecule selective sphingosine-1-phosphate (S1P) receptor modulator being developed by Pfizer for the treatment of ulcerative colitis and other immune-mediated inflammatory disorders. Etrasimod is selective for S1P receptor subtypes S1P₁, S1P₄ and S1P₅ while having minimal activity on S1P₃ and no activity on S1P₂. Etrasimod received its first approval, in the USA, in October 2023 for the treatment of moderately to severely active ulcerative colitis in adults. Subsequently, the European Medicines Agency adopted a positive opinion in December 2023, recommending the granting of marketing authorisation for etrasimod for the treatment of patients aged ≥ 16 years with moderately to severely active ulcerative colitis who have had an inadequate response, lost response, or were intolerant to either conventional therapy, or a biological agent. Etrasimod is also under regulatory review for the treatment of ulcerative colitis in several other countries. Clinical development of etrasimod for use in the treatment of Crohn's disease, atopic dermatitis, eosinophilic oesophagitis and alopecia areata is ongoing worldwide. This article summarises the milestones in the development of etrasimod leading to this first approval for the treatment of ulcerative colitis in adults.