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

How Effective is Etrasimod?

Clinical Remission Efficacy

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

Clinical studies have shown that this drug 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 Features

Once-daily oral administration improves medication convenience.

It remains effective in patients who have 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.

Indicated Populations for Etrasimod

Characteristics of Target Patients

Adult patients with moderately to severely active ulcerative colitis.

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

Patient populations with virological suppression achieved and no drug resistance.

Contraindicated Populations

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

Patients with decompensated heart failure requiring hospitalization or New York Heart Association (NYHA) Class III/IV heart failure.

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

Medication Monitoring for Etrasimod

Pre-Treatment Evaluation

Complete blood count (including lymphocyte count).

Electrocardiogram (ECG) to assess cardiac conduction function.

Liver function tests (transaminase and bilirubin levels).

Fundus examination (including assessment of the macula).

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

Varicella-zoster virus (VZV) antibody testing (if there is no clear history of infection or vaccination).

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 monitor changes in visual acuity.

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

Closely monitor changes in heart rate and rhythm during the initial phase of medication use.

Patients using immunosuppressants need to be monitored for infection risk.

Monitoring for the effects on the immune system is still required within 5 weeks after drug discontinuation.

Women of childbearing age must ensure effective contraceptive measures.