Safety, Efficacy, and Pharmacokinetics (PK) Study of Trans Sodium Crocetinate (TSC) in Patients With Intermittent Claudication

Inclusion Criteria: * Aged 40 or older, male or female * 6-mo. history of walking limitation or symptoms of intermittent claudication (IC) in at least 1 lower limb, severity of which has not changed in the past 3 mo. and diagnosed by principal investigator as clinically stable Fontaine Stage II peripheral artery disease (PAD) * Diagnosis of PAD secondary to atherosclerosis * If ankle-brachial index (ABI) is \> 1.3 or cannot be measured in either leg, vascular etiology documented by toe-brachial index (TBI) ≤ 0.7 in at least 1 leg * Claudication severity, meds. for the treatment of coronary artery disease (CAD), PAD and IC, and exercise habits should be clinically stable for 3 mo. prior to Screening (SCRN) and during study. Pt. is not likely to change smoking and/or exercise habits during study * On an exercise treadmill test (ETT), peak walking time (PWT) of at least 1 min., but no more than 12 min. at Baseline * Willing and able to discontinue Pletal or Trental for 21 days before SCRN and during study * Antihypertensive therapy, cholesterol-lowering therapy, chronic oral nitrates, and diabetic therapy have been stable for 30 days prior to SCRN * Willing and able to provide written, signed, informed consent after the nature of the study has been explained and prior to any research-related procedures * Willing and able to comply with all study-related procedures * Sexually active patients must use an acceptable method of contraception while participating in the study * Females of childbearing potential must have a negative pregnancy test at SCRN and have additional pregnancy tests during the study Exclusion Criteria: * Pregnant or lactating * Current or history of critical limb ischemia (CLI) * Pts. in whom artery insufficiency in the lower extremity is the result of acute limb ischemia (ALI) or an immunological or inflammatory non-atherosclerotic disorder * Pts. in whom walking impairment due to pain is the result of other non-atherosclerotic co-morbid conditions * A surgical intervention to alleviate symptoms of IC or PAD-specific endovascular intervention or cardiovascular surgery within 3 mo. of SCRN * Walking limited by reasons other than claudication * Conditions other than IC of significant severity that could confound PWT on the ETT * Concurrent severe congestive heart failure (CHF) * Life-threatening ventricular arrhythmias, unstable angina, and/or myocardial infarction (MI) within 3 mo. before enrollment (ENRL) * Coronary artery bypass grafting or percutaneous coronary intervention within 4 mo. before ENRL * Renal and/or carotid revascularization procedure within 3 mo. of ENRL * Transient ischemic attack (TIA) within 3 mo. before ENRL * Deep vein thrombosis (DVT) within 3 mo. before ENRL * Severe chronic obstructive pulmonary disease (COPD) * Thrombocytopenia * Undergoing hemodialysis or peritoneal dialysis * Pts. w/immunocompromised conditions, organ transplant recipients and/or need for immunosuppressive therapy * Neurological dementia * Stroke * Clinically significant electrocardiogram (ECG) change during or after ETT at SCRN or Baseline visit(s) * Cerebrovascular infarct within 3 mo. of SCRN * Poorly controlled type 1 or type 2 diabetes at SCRN * History of migraine headaches within last 12 mo. * Patients with clinically significant abnormal hematology labs or blood chemistry labs * Body mass index \> 35 * Hypertension at SCRN defined as resting BP values of \> 170 mmHg systolic and/or \> 110 mmHg diastolic * Hypotension at SCRN defined as resting BP values \< 100 mmHg systolic or \< 55 mmHg diastolic or symptomatic hypotension * Previous treatment with any formulation of TSC * Known allergy or hypersensitivity to any excipient (gamma-cyclodextrin, mannitol, glycine) of TSC formulation * Previous treatment with gene therapy or other VEGF-related treatment within 12 mo. of SCRN * Patients with recent history of alcoholism or drug abuse, or severe emotional, behavioral, or psychiatric problems * Patients receiving experimental medications or participating in other study using an experimental drug or procedure within 45 days prior to ENRL