A Study to Learn How the Study Medicine Called Etrasimod is Taken up Into Blood and Breastmilk of Healthy Breastfeeding Women

Inclusion Criteria

• •Inclusion
• •1. Healthy (as determined by medical evaluation including medical history, physical examination, laboratory tests, vital signs and 12-lead ECGs) lactating women who are actively breastfeeding or expressing breast milk, who are at least 12 weeks post partum and not currently pregnant (must have a negative pregnancy test), and must be 18 to 55 years of age, inclusive, at the time of signing the informed consent document (ICD).
• •2. Body mass index (BMI) of 16-35 kg/m2; and a total body weight \>45 kg (99 lb).
• •3. Participants must be willing to temporarily discontinue breastfeeding their infants for a total of 21 days, ie, from the evening of the day before Day 1 through to 14 days after the last dose (approximately 8 AM the morning of Day 21). Participants must be willing to regularly pump breasts throughout the study and express breast milk according to a schedule designed to maintain lactation until the completion of breast milk collection
• •Exclusion
• •1. Evidence or history of clinically significant hematological, renal, endocrine, pulmonary (such as moderate or severe chronic pulmonary disorders like asthma or chronic obstructive pulmonary disease \[COPD\]), gastrointestinal, cardiovascular, hepatic, neurological/psychiatric, anaphylactic, ophthalmologic disorders (such as macular edema, uveitis, retinopathy), or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
• •2. Participants with history or presence of second-degree or third-degree atrioventricular (AV) block, sick sinus syndrome, or sinoatrial block.
• •3. Resting HR \<50 bpm at Screening or pre-randomization on Day 1. Measurement can be repeated up to 3 times to confirm the finding. Mean values will be used if repeated.
• •4. Recurrent symptomatic bradycardia or recurrent cardiogenic syncope
• •5. Any condition possibly affecting drug absorption (eg, gastrectomy, cholecystectomy).
• •6. Known immunodeficiency disorder, including positive serology for human immunodeficiency virus (HIV), or a first degree relative with a hereditary immunodeficiency, and history of organ transplant (except corneal transplant).
• •7. History or evidence of hepatitis B or hepatitis C viruses. Hepatitis B vaccination is allowed.89.
• •8. Participants with any of the acute or chronic infections or infection history