Etrasimod is a sphingosine 1-phosphate (S1P) receptor modulator. It was approved for marketing by the U.S. FDA in 2023 for the treatment of moderate to severe active ulcerative colitis (UC) in adults. As a novel oral targeted medication, it exerts its therapeutic effect by regulating lymphocyte migration.

What Is the Therapeutic Efficacy of Etrasimod?

Clinical Remission Efficacy

Etrasimod reduces the number of peripheral blood lymphocytes by reversibly blocking the migration of lymphocytes from lymphoid tissues to the periphery, thereby alleviating intestinal inflammation.

Clinical studies have shown that this medication can significantly improve the clinical symptoms and endoscopic findings of patients with ulcerative colitis, achieving clinical remission.

Its main evaluation indicators include the comprehensive improvement of stool frequency score, rectal bleeding score, and endoscopic score.

Therapeutic Advantages and Characteristics

Once-daily oral administration improves medication convenience.

It remains effective in patients with an inadequate response to conventional treatments (such as aminosalicylates and corticosteroids).

It still shows therapeutic effects in some patients who have previously used biological agents or JAK inhibitors.

Applicable Population of Etrasimod

Characteristics of Target Patients

Adult patients with moderate to severe active ulcerative colitis.

Patients with inadequate response, loss of response, or intolerance to conventional treatments.

Patient population with virological suppression achieved and no drug resistance.

Contraindicated Population

Patients who have experienced myocardial infarction, unstable angina pectoris, stroke, or transient ischemic attack (TIA) within the past 6 months.

Patients with decompensated heart failure requiring hospitalization or Class III/IV heart failure.

Patients with a history of Mobitz Type II second-degree or third-degree atrioventricular block, sick sinus syndrome, or sinoatrial block (unless the patient has a properly functioning cardiac pacemaker implanted).

Medication Monitoring of Etrasimod

Pre-Treatment Assessment

Complete blood count (including lymphocyte count).

Electrocardiogram to assess cardiac conduction function.

Liver function tests (transaminase and bilirubin levels).

Fundus examination (including macular assessment).

Skin examination (especially for patients with risk factors for skin cancer).

Varicella-zoster virus antibody testing (if there is no clear medical history or vaccination record).

Key Monitoring Items During Treatment

Infection Monitoring: Pay attention to infection symptoms such as fever and fatigue; consider discontinuing treatment in case of severe infection.

Cardiac Monitoring: Monitor changes in heart rate and be alert to bradycardia and atrioventricular block.

Liver Function Monitoring: Conduct timely liver function tests when symptoms such as jaundice and abdominal pain occur.

Ophthalmic Monitoring: Perform regular fundus examinations and pay attention to visual changes.

Blood Pressure Monitoring: Elevated blood pressure may occur during treatment.

Respiratory Function Monitoring: Evaluate changes in lung function and pay attention to new or worsening respiratory symptoms.

Special Monitoring Requirements

Close monitoring of heart rate and rhythm changes is required in the early stage of medication use.

Patients using immunosuppressants need to be monitored for infection risk.

Monitoring of the impact on the immune system is still necessary within 5 weeks after drug discontinuation.

Women of childbearing age must ensure effective contraceptive measures.