• Time to major amputation of the treated leg or death from any cause, whichever comes first [ Time Frame: over 12 months ]
  

• Adverse events
  
• Laboratory parameters
  

Inclusion Criteria:

• Having peripheral artery disease at the stage of Critical Limb Ischemia (CLI) with skin lesions (either ulcer(s) or gangrene)
• With objective evidence of CLI such as ankle systolic pressure less than 70 mmHg and/or toe systolic pressure less than 50 mmHg or TcPO2 less than 30 mm Hg
• Unsuitable for standard revascularization of his/her peripheral arterial disease
• Having a negative screening for cancer

Exclusion Criteria:

• Previous major amputation on the leg to be treated or planned major amputation within the first month following randomization
• Known Buerger's disease
• Successful lower extremity revascularization procedure within 3 months prior randomization
• Uncontrolled blood pressure defined as SBP≥ 180 mmHg or DBP ≥110 mmHg despite adequate antihypertensive treatment
• Acute cardiovascular events within 3 months prior to randomization
• Active proliferative retinopathy and severe macular oedema
• Previous or current history of malignant disease within the past 5 years
• Previous treatment with growth angiogenic factors or with stem cells therapy
• Pregnant or breast-feeding women or women of childbearing potential not protected by an effective contraceptive method of birth control

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.