Etrasimod is a sphingosine 1-phosphate (S1P) receptor modulator indicated for the treatment of moderate to severe active ulcerative colitis (UC) in adults.

How to Use Etrasimod

Conventional Dosage and Administration

Recommended Dosage: Orally administer 2mg once daily, either with food or on an empty stomach.

Dosage Form and Specification: 2mg tablets, which are round, green, film-coated tablets engraved with "ETR" on one side and "2" on the other side.

Administration Requirement: Swallow the tablet whole; do not break or chew it.

Pre-Treatment Evaluation

Blood Tests: Complete blood count (CBC), including lymphocyte count.

Cardiac Evaluation: Electrocardiogram (ECG) to detect the presence of conduction abnormalities.

Liver Function Tests: Measurement of transaminase and bilirubin levels.

Ophthalmic Examination: Baseline evaluation of the fundus and macula.

Vaccination: If the patient has not received the varicella vaccine or has negative varicella antibodies, vaccination should be completed 4 weeks before the start of treatment.

Precautions for Medication Use

Infection Risk: Monitor for signs of infection (e.g., fever, fatigue) during treatment and for 5 weeks after discontinuing the medication.

Cardiac Monitoring: A transient decrease in heart rate may occur after the first dose; be alert to symptoms such as dizziness and weakness.

Dosage Adjustment and Contraindications of Etrasimod

Situations Not Requiring Dosage Adjustment

Patients with mild to moderate hepatic impairment (Child-Pugh Class A/B).

Patients with mild to moderate renal impairment.

Contraindications

Cardiovascular Events: Myocardial infarction, unstable angina, stroke, or Class III/IV heart failure occurring within the past 6 months.

Conduction Abnormalities: Mobitz Type II second-degree atrioventricular block or third-degree atrioventricular block without a pacemaker, and sick sinus syndrome.

Situations Requiring Treatment Suspension or Discontinuation

Severe Infections: If active infection is confirmed, suspend treatment until the infection is controlled.

Liver Injury: If transaminase levels increase to ≥3 times the upper limit of normal (ULN) accompanied by elevated bilirubin, permanently discontinue the medication.

Medication Use in Special Populations for Etrasimod

Pregnant Women

Animal studies have shown embryotoxicity, which may cause fetal malformations.

Etrasimod is contraindicated during pregnancy; women must use highly effective contraceptive measures during treatment and for 1 week after discontinuing the medication.

Lactating Women

Etrasimod may be excreted in breast milk; a careful balance of benefits and risks should be considered during lactation, or breastfeeding should be suspended.

Patients with Hepatic Impairment

Severe Hepatic Impairment (Child-Pugh Class C): Use is not recommended.

No dosage adjustment is needed for mild to moderate hepatic impairment, but close monitoring of liver function is required.