The purpose of this study is to evaluate if TD-4208, an investigational drug being developed to treat people with chronic obstructive pulmonary disease (COPD), has any effect on the electrical activity of the heart.

Inclusion Criteria:

• Subject has a body mass index (BMI) of 19 to 32 kg/m2, inclusive, and weight of at least 55 kg.
• Subject is able to communicate well with the investigator and to comply with the study procedures, requirements, and restrictions.

Exclusion Criteria:

• Subject has a prior history of myocardial infarction, acute coronary syndrome, cerebrovascular accident, transient ischemic attack, ventricular tachycardia, atrial fibrillation, personal or known family history of congenital long QT syndrome or known family history of sudden death with unknown cause, a pacemaker or implantable cardioverter defibrillator, cardiac or cerebral stent placement or angioplasty, or clinically significant valvular heart disease.
• Subject has evidence or history of clinically significant allergic (except for untreated, asymptomatic, seasonal allergies at time of dosing), hematologic, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, or neurological disease.