Inclusion Criteria:  The subject is 18 to 55 years of age, inclusive, with a body mass index (BMI) 18 to 33 kg/m2, inclusive, at screening. The subject is considered by the investigator to be in good general health as determined by medical history, clinical laboratory test results, vital sign measurements, 12-lead ECG results, and physical examination findings at screening. The subject is able to provide written informed consent and agrees to comply with all protocol requirements.  Exclusion Criteria:  The subject has a history of risk factors for torsades de pointes, including unexplained syncope, known long QT syndrome, heart failure, myocardial infarction, or angina. The subject has a family history of long QT syndrome, Brugada syndrome, or sudden death. The subject has a resting HR of <40 bpm or >100 bpm when vital signs are measured at screening or check-in. The subject has history or presence of unstable cardiovascular disease, including myocardial infarction, cardiac arrhythmia, or cerebrovascular disease (eg, cerebrovascular accident/stroke or transient ischemic attack). The subject has a history of other acute or chronic cardiovascular disease or coronary revascularization surgery (eg, coronary artery bypass graft, percutaneous transluminal coronary angioplasty). The subject uses a cardiac pacemaker. The subject has a history of any other medical, psychological, or social condition that, in the opinion of the investigator or the medical monitor, would prevent the subject from fully participating in the study, would represent a concern for study compliance, or would constitute a safety concern to the subject.