A Study to Define the ECG Effects of Tizanidine Compared to Placebo and the Positive Control, Moxifloxacin, in Healthy Men and Women Using a Blinded ECG Evaluator: A Thorough ECG Trial

Inclusion Criteria: * Women of childbearing potential should have a negative urine pregnancy test prior to Screening and Day -2 of the trial * All subjects of childbearing potential must practice a highly effective method of birth control excluding oral contraceptives for the duration of the trial and up to 3 months after the last dose of investigational product. Oral contraceptives are not allowed, based on the precaution listed in the Zanaflex package insert. * Have a body mass index (BMI) ranging between 19 and 30 kg/m2 * Comprehend and be able to provide written informed consent * Be willing and able to comply with all trial requirements Exclusion Criteria: * Female who is either pregnant, breastfeeding or planning to become pregnant * History of hypersensitivity or allergic reaction to tizanidine or moxifloxacin or any of the tablet components * Any condition possibly affecting drug absorption, metabolism or excretion including previous surgery for removal of parts of stomach, bowel, liver, gall bladder, or pancreas * History of Long QT Syndrome or a first-generation relative with this condition * Evidence or history of clinically significant allergies except for untreated, asymptomatic, seasonal allergies at time of dosing, hematological, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, renal, psychiatric, or neurological disease. Determination of clinical significance is to be made at the Investigator's discretion * History or presence of any malignant or benign neoplasm considered by the investigator to be clinically significant * History of drug or alcohol abuse or dependence within the last year * Have an active infectious disease