Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) and Mobilization of Progenitor Cells in Peripheral Arterial Disease (GPAD-2)

Inclusion Criteria:

• 160 males or post-menopausal females between 21 and 80 years of age. Female subjects must be (a) post-menopausal, (b) surgically sterile or (c) use adequate birth control and have a negative pregnancy test within 3 days prior to administration of study drug and should not be breastfeeding.
• Documented PAD (By Ankle-Brachial Indices or Angiographically)
• Clinically stable (at least 2 months) history of intermittent claudication with no change in symptom severity in the 2 months prior to screening.
• On stable statin therapy for previous 3 months.
• Peak Walking Time (PWT) between 1 and 12 minutes on a standardized Gardner treadmill protocol.
• A Doppler-derived ankle-brachial index (ABI) of < 0.85 in the symptomatic limb after 10 minutes of rest at screening. For subjects with an ABI of >1.3 (non-compressible arteries) a Toe-Brachial Index (TBI) of < 0.70 must be obtained for subject qualification, or if ABI is > 0.85 to 1.0 , and a reduction of 20% in ABI measured within 1 minute of treadmill testing.
• On appropriate and stable medical therapy for atherosclerosis for at least 2 months.
• Able to give informed consent.
• Diabetics with a dilated eye exam excluding proliferative retinopathy in the previous 12 months.

Exclusion Criteria:

• Recent or current active infections (treated with antibiotics).
• Recent (3 months) change in statin therapy
• Critical limb ischemia either chronic (category 3 and 4 of SVS classification) or acute ischemia manifested by rest pain, ulceration, or gangrene.
• Lower extremity vascular surgery, angioplasty or lumbar sympathectomy within 3 months of enrollment.
• Participation in a structured exercise treatment protocol within 3 months of enrollment.
• Prior myeloid cancer.
• Unstable angina, myocardial infarction, TIA, stroke or revascularization in the preceding 4 months.
• Severe heart failure (Class III or IV), heart muscle disease or atrial fibrillation.
• Limitation on exercise for symptoms other than intermittent claudication such as arthritis or dyspnea.
• Uncontrolled diabetes mellitus (defined as HbA1c > 10.0).
• Chronic renal disease (creatinine of >2.5 mg/dl) or hepatic disease (> 3 X elevations in AST and ALT).
• Ophthalmologic conditions associated with a neo-vascular response.
• Alcohol or drug abuse, or any other disease process that, in the opinion of the PI, will interfere with the ability of the patient to participate in the study.