The clinical trial aims to study the safety and efficacy of adult allogeneic mesenchymal stem cells for the treatment of critical limb ischemia.

Inclusion Criteria:

1. Males or females in the age group of 18-80 yrs of Caucasian origin.
2. Peripheral artery disease (PAD) against the background of atherosclerosis and diabetes mellitus (DM)
3. Critical lower limb ischemia (stages 3-4 by Fontaine-Pokrovsky or stages 4-6 by Rutherford)
4. Patients with remaining symptoms of critical limb ischemia (CLI) in spite of the performed surgical (endovascular or open) treatment and continuing conservative therapy
5. Patients with absent emergency indications to major amputation
6. Patients planned for the reconstructive surgery with a questionable remote outcome due to compromised blood outflow
7. Ankle Brachial Pressure Index (ABPI) ≤ 0.5 or ankle pressure ≤ 70 mm Hg
8. Patients, if having associated Type II Diabetes, should be on medication and well controlled (HbA1c ≤ 8.5 %)
9. On regular medication for hypertension if needed
10. Normal liver and renal function (or having clinically insignificant deviations, according to the treating physician's opinion)
11. Patients who are able to understand the requirements of the study, and willing to provide voluntary written informed consent, abide by the study requirements, and agree to return for required follow-up visits

Exclusion Criteria:

1. Humid gangrene or acute/chronic infection of lower limb.
2. Dry gangrene with extensive foot lesion (> 1\2).
3. Acute arterial failure.
4. Life-threatening conditions and predicted life expectancy of < 6 months.
5. Presence of neoplasm or bone marrow disease
6. Signs of active or chronic, including latent, haemorrhage
7. Any acute or chronic infectious disease
8. Renal failure determined as twofold or higher elevation of serum creatinine as compared to the upper normal limit
9. Hepatic failure determined as the bilirubin, alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels elevated by two and more times over the upper normal limits
10. Thrombocytopenia (platelet counts < 50,000 /µl), leukocytopenia (WBC < 4,000/µl), immunosuppressive therapy
11. Pronounced neurological deficit
12. Patients with gait disturbance for reasons other than CLI
13. Patients not suitable for cell therapy, by the treating physician's opinion
14. CLI patients requiring amputation at the proximal to the trans-metatarsal level
15. Patients with Type I diabetes
16. Patients having respiratory complications/left ventricular ejection fraction < 25%
17. Stroke or myocardial infarction within last 3 months
18. Patients who are contraindicated for X-ray angiography
19. History of severe alcohol or drug abuse within 3 months of screening
20. Pregnant and lactating women.
21. Patients tested positive for HIV 1, hepatitis C virus (HCV), hepatitis B virus (HBV)
22. Unsigned informed consent