Peripheral Arterial Occlusive Disease (PAOD) is a condition caused by ischemia in the legs due to atherosclerotic disease affecting the larger arteries of the legs. Chronic PAOD can be regarded as a marker of generalized atherosclerosis. PAOD threatens the survival of an extremity and often causes lifelong disablement from a painful leg. The clinical consequences of PAOD include pain on walking (claudication), pain at rest and loss of tissue integrity in the distal limbs.A variety of medical therapies have been investigated for patients with PAOD. There is currently no evidence to suggest that any medical therapy is effective for patients with rest pain and/or ischemic ulcers.

Also, the use of intramuscular angiogenic VEGF-A gene transfer has recently demonstrated a improvement in clinical and hemodynamic status in patients with severe PAOD

Inclusion Criteria:

1. Informed consent was to be signed before proceeding with any study procedure.
2. Patients with severe PAD.
3. Trophic lesions with no signs of healing (no reduction in ulcer size or depth) for at least 2 weeks prior to first study treatment administration (Day 1).
4. Patients with objective evidence of peripheral vascular disease in the diseased limb on 2 consecutive examinations performed at least 1 week apart.
5. Demonstration or documentation of total occlusion of the affected limb of one or more of the iliac, superficial femoral, popliteal and/or one or more infrapopliteal arteries as assessed by angiography or magnetic resonance angiography (MRA)
6. Transcutaneous oxygen pressure (TcPO2): mean resting supine TcPO2 of the foot of ≤40 mmHg based on 2 separate measures performed at least 1 week apart
7. Poor/not candidates for revascularization

Exclusion criteria

1. Previous or current history of malignant disease.
2. Positive cancer screening (liver, prostate, colon, cervix, breast, lung)
3. Successful lower extremity surgery (bypass/angioplasty of the leg to be treated) within 3 months prior to the first administration of study treatment [Day 1]).
4. Patients planned to undergo amputation of target limb within 1 month following the first administration of study treatment.
5. Patients with a history of severe renal failure.
6. Creatinine >2.0 mg/dL (176 µmol/L) or estimated creatinine clearance <30 mL.
7. Serious concomitant medical conditions not adequately controlled (other than severe PAD),
8. Buerger's disease.
9. Patients in dialysis.
10. Active proliferative retinopathy
11. Patients who had a stroke or neurologic deficit presumed to be due to stroke within 3 months prior to the first administration of study treatment.
12. Previous treatment with any angiogenic growth factor.
13. Positive serology for HIV 1 or 2.
14. Participation in clinical trials of non-approved experimental agents within 4 weeks before study entry.