This is a single center, open label, prospective, randomized, controlled study in patients with non- revascularizable moderate or severe lower extremity PAD receiving autologous stem cells therapy. We will enroll a maximum of 10 subjects in this study. The patients will be divided into two groups. One group will receive ADSCs alone and the other group will receive low frequency ultrasound before the addition of ADSCs. The randomization will be 1:1. If the results of this pilot study are not clearly different, there will be a need for a phase II study to support the results.

Baseline, 6 week, 3 month and 6 month assessments of 6 min walking distance, ABIs/TBIs, TcPO2, Rutherford assessments will be performed for the study group. Prior to the stem cell treatment, the ultrasound group patient will receive noninvasive transcutaneous pulsed focused ultrasound around the involved vessel(s) in the affected extremity. All patients will then receive 100 to 200 million autologous adipose derived stem cell therapy: 1/3 of the cells will be delivered intra-venous proximal to the lesion (not retrograde), 1/3 of the cells will be delivered intra- adventitia proximal to the lesion and 1/3 of the cells will be delivered by intra- muscular injection along the vessel path (20-30 injections each separated by 1.5 inch). Standard therapy for PAD patients will not be interrupted for the duration of the study. Standard therapy for PAD is defined as cardiovascular general measures like lifestyle changes, smoke cessation, exercise, cardiovascular rehabilitation, etc. All participants have already received maximal non-surgical therapy. Safety will be monitored on an ongoing basis.

SUBJECT PARTICIPATION A screening evaluation to determine if a potential subject is suitable for participation in this trial will be conducted prior to enrollment and treatment by the Investigator. This includes obtaining written informed consent, collection of a complete medical history, including current and past medications, physical examination and clinical laboratory tests, PAD related testing (ABI/TBI, 6MWT, TcPO2, QoL questionnaires, etc.).

Eligible subjects will be randomized and treated at the Sponsor hospital as approved by the sponsor. Study medical staff will evaluate the patients upon admission according to the scheduled medical assessments to ensure eligibility of the subjects. Ultrasound group will receive LFUS over the affected limb (see page XIV). Intra-venous, intra-adventitia and intramuscular dosing of the autologous ADSC will occur on the morning of Day 0. Conscious sedation (I.V.) may be used during the tissue harvesting and intra-adventitia administration of the cells.. Subjects must remain in the clinic/hospital until they are clinically stable for discharge; subjects that are clinically stable will be discharged into the care of a responsible individual. Follow-up visits will occur at 6 weeks and 3 and 6 months post-treatment, and may occur with the patient's personal physician who will be provided the follow-up assessment forms. If this occurs, the Investigator and/or Sponsor or sponsor's designee may also contact the patient by telephone to collect follow-up safety information. Adverse events, concomitant medications, vital signs, clinical laboratory test results and physical examinations will be collected or conducted at follow-up visits according to the schedule of assessments (Appendix B). All previous medical care, including medications and rehabilitation, for the patient's current medical conditions will be continued as prescribed by the patient's personal physician(s). Use of other investigational agents or treatments is not allowed during this study.