Safety and Efficacy Study of Autologous BM-MNC Processed by Two Methods for Treating Patients With Chronic Limb Ischemia

Safety and Efficacy Study of Autologous BM-MNC Processed by Two Methods for Treating Patients With Chronic Limb Ischemia

Transplantation of Autologous BM-MNC Processed by ResQ Separator and Conventional Manual Method for Patients With Chronic Limb Ischemia: a Multi-center Randomized Controlled Trial

Using autologous bone marrow mononuclear cells (BM-MNC) to treat patients with chronic limb ischemia has been proved safe and effective. However, processing bone marrow by Ficoll density gradient centrifugation is not only time consuming but also expensive. Manually processing of bone marrow also results in large variation in therapeutic cell quantity and quality which directly leads deviation of safety and efficacy of the cell therapy. This study is aiming to compare an automated bone marrow processing system with a conventional manual method in term of safety and efficacy.

Using autologous bone marrow mononuclear cells (BM-MNC) to treat patients with chronic limb ischemia has been proved safe and effective. However, processing bone marrow by Ficoll density gradient centrifugation is not only time consuming but also expensive. Manually processing of bone marrow also results in large variation in therapeutic cell quantity and quality which directly lead deviation of safety and efficacy of the cell therapy. This study is aiming to compare an automated bone marrow processing system with a conventional manual method in term of safety and efficacy. ResQ system developed by Thermogenesis in USA provides an automatic cell processing system for bone marrow. The system takes less than 30 minutes to concentrate the therapeutic mononuclear cells including stem cells in a closed system without adding any additive such as separation reagent (Ficoll). The system also be able to be operated at point of care. The study is designed to prove no inferior of safety and efficacy of bone marrow cells processed by ResQ to those of cells using conventional manual method. The conventional manual method is involved Ficoll density gradient centrifugation and cell washing stems in an open system. Each of test arms (ResQ vs manual method) consists of 25 patients. The primary outcome is safety which is measured by cell treatment-related adverse events. The secondary endpoints include resting ankle-brachial pressure index (ABI)and toe brachial pressure index (TBI) , transcutaneous oxygen pressure (TcPO2), claudication distance, rest pain scale evaluation, collateral vessel scale, etc.

Peripheral arterial disease, Buerger's disease, atherosclerotic arterial occlusion, bone marrow mononuclear cell, chronic limb ischemia

Autologous BM-MNC is enriched with ResQ process(an automatic cell separator). Then the cell product is transplanted into the ischemia limbs of a patient.

Temperature,Pulse,Respiration,Blood Pressure Routine analysis of blood and urine, Liver function(ALT：alanine aminotransferase,AST：aspartate transferase), Renal function(Blood urea nitrogen,Creatinine;) Function of coagulation(APTT,PT,Fib,TT） ECG（Electrocardiography） local inflammatory response Cell-treatment related death Cell-treatment related unexpected amputation.

Measuring ulcer area (cm2) and depth (mm)of limb : For each ulcer , photographically record the area and depth with a ruler in order to calculate the ulcer area in square millimeters.

Scoring the rest pain based on the degree of pain as following five scales): 0 level-0 point: no pain; level-1 point: occasional pain which can be recalled; level-2 points: the pain often but can be tolerated, without or with a little analgesics; level-3 points: often with need of general analgesics; level -4 points: affect sleeping due to the pain, general pain medication being difficult to alleviate. Before transplantation: points; after transplantation: points.

based on a sense of cold as following five scales: 0 level-0 point: no cold sensation; level-1 point, or : Accasionally cold feeling; level-2 points: Often with cold feeling; level-3 points: significantly cold feeling. and can be significantly improved when using a local insulation. level-4 points: significantly cold feeling，and can not be significantly improved when using a local insulation.

Measurement of claudication distance (m)： For patients with intermittent claudication, treadmill exercise test (no tilt, speed 3km/hr) is employed to measure claudication distance.

Measurement of ABI(ankle brachial index, ABI): Measure arterial pressure with a laser Doppler, and then calculate the ankle-brachial index, that is a ratio of ankle arterial blood pressure to brachial arterial blood pressure at rest.

Transcutaneous oxygen pressure(TcPO2) should be measured at the same site in the ischemic limb at rest.

Collateral vessel score: Using DSA(Digital subtraction angiography)or CTA(computed tomographic angiography) to score the collateral vessel formation. A mean score is obtained for each ischemic limb by 3 independent interventionists based on the following 4 level score: 0 (no new collateral vessels) 1 (A little new collateral vessels) 2 (moderate new collateral blood vessels) 3 (Rich new collateral vessels)

using PeriMed "laser-Doppler flowmetry" measure the skin microcirculation on the same site in the ischemic limb at rest.

Measurement of TBI（Toe Brachial Index): Measure arterial pressure with a laser Doppler, and then calculate Toe Brachial Index, that is a ratio of toe arterial blood pressure to brachial arterial blood pressure.

Inclusion Criteria: fontaine's stage 2-4 or resting ABI <0.7 age between 20 and 80 years old sign informed consent, voluntary subjects diagnosis of lower extremity arterial occlusive disease, or diabetic lower limb ischemia, or Buerger's disease Exclusion Criteria: poorly controlled diabetes (HBA1c> 7.0%) and proliferative retinopathy (III-IV stage) malignancy history in the past five years or serum level of tumor markers elevated more than doubled severe heart, liver, kidney, respiratory failure or poor general condition can not tolerate BM-MNC transplantation serious infections (such as cellulitis, osteomyelitis, etc.)or gangrene that a major amputation cannot be avoided aortic or iliac or common femoral artery occlusion pregnant female, or reproductive age female who wants to give birth throughout the course of the study life expectancy less than a year