The purpose of this study is to explore the cardiac pharmacodynamics, safety and tolerability of MT-1303 in healthy subjects.

Inclusion Criteria:

• Healthy and free from clinically significant illness or disease.
• Male and female subjects of non-childbearing potential aged 18 to 55 years.
• Normal or non-clinically significant 12-lead ECG.
• Holter recording with no clinically significant abnormalities.
• Systolic blood pressure: 90 to 140 mmHg, diastolic blood pressure: 50 to 90 mmHg

Exclusion Criteria:

• A History of severe adverse reaction or allergy to any medical product.
• Clinically significant endocrine, thyroid, hepatic, respiratory, gastrointestinal, renal, cardiovascular disease, eye disorder or history of psychiatric/psychotic disorder.
• A history of tuberculosis.
• Have a positive HBsAg, HBcAb, HCVAb or HIV-1 and HIV-2 test.
• Previously having received MT-1303, fingolimod, or any other sphingosine-1-phosphate receptor modulators.
• Clinical relevant abnormal medical history, or physical findings or laboratory values.
• Clinically significant 12-lead ECG abnormalities.
• Clinical relevant abnormal findings in echocardiograph.