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Effect of Cilostazol Endothelial Progenitor Cells and Collateral Formation in Peripheral Occlusive Artery Disease (PAOD)

This study has been completed.
Department of Health, Executive Yuan, R.O.C. (Taiwan)
Information provided by (Responsible Party):
National Cheng-Kung University Hospital Identifier:
First received: September 21, 2013
Last updated: July 16, 2014
Last verified: July 2014
  1. The number and function of circulating endothelial progenitor cells (EPCs) are inversely associated with coronary risk factors and atherosclerotic diseases such as PAOD.
  2. This double-blind, randomized, placebo-controlled trial to evaluate the effects of cilostazol on human early EPCs and angiogenesis as well as the potential mechanisms of action in patients with mild-to-moderate PAOD.

Condition Intervention Phase
Peripheral Arterial Diseases
Drug: Cilostazol
Drug: Dummy Placebo
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Cilostazol Enhances the Number and Functions of Circulating Endothelial Progenitor Cells and Collateral Formation Assessed by Dual-energy 128-row CT Angiography Mediated Through Multiple Mechanisms in Patients With Mild-to-moderate PAOD

Resource links provided by NLM:

Further study details as provided by National Cheng-Kung University Hospital:

Primary Outcome Measures:
  • Circulating EPCs Number [ Time Frame: 3 months ]
    Peripheral blood mononuclear cells (one million cells in each) are suspended in 100 µL phosphate-buffered saline and incubated for 30 min with monoclonal antibodies against human peridinin chlorophyll protein-conjugated cluster of differentiation antigen-45, phycoerythrin-conjugated anti-human cluster of differentiation antigen-34 antibody and anti-human kinase insert domain receptor (KDR) antibody conjugated with Alexa Flour 647. Cells are washed and analyzed on a FACSCalibur flow cytometer with 100,000 events in the lymphocyte gate. EPCs, which are defined as negative for cluster of differentiation antigen-45 and positive for cluster of differentiation antigen-34 and KDR. Based on the peripheral blood mononuclear cell counts, the absolute number of circulating EPCs/µL is calculated.

Secondary Outcome Measures:
  • Colony Formation by EPCs [ Time Frame: 3 months ]
    Peripheral blood mononuclear cells are isolated by density gradient centrifugation according to standard protocols. After centrifugation, cells are washed, resuspended in M199 medium supplemented with 20% (vol/vol) fetal bovine serum, 10 ng/ml vascular endothelial growth factor, 2 ng/ml basic-fibroblast growth factor, 10 ng/ml epidermal growth factor and 2 ng/ml insulin growth factor, and cultured in 24-well plates coated with human fibronectin for 7 days. EPCs cells are confirmed by uptake of acetyl-low density lipoprotein and lectin and by the expression of EPC markers. Cells are harvested after 7 days, fixed and stained with crystal violet reagent. The colony densities are quantified with an Olympus microscope at 100-fold magnification using an imaging measurement software.

Other Outcome Measures:
  • Viability (Proliferation) of EPCs [ Time Frame: 3 months ]
    250,000 cells are seeded in each well of a 96-well plate and the cells are added with 200 μl of the culture medium and incubated at 37°C. Medium change is performed 3 days later. On 7th day, the plate is then re-incubated with 100 μl fresh medium and additional 50 μl of 2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2 Hydrogen-Tetrazolium-5-Carboxanilide reagent, and further incubated in dark at 37°C for 4 h. After incubation, the orange colored complex formed is read at 450 nm using a microplate reader with a 450 nm reference filter.

Enrollment: 44
Study Start Date: January 2012
Study Completion Date: September 2013
Primary Completion Date: September 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Cilostazol
One tablet (100 mg) twice per day for 12 weeks
Drug: Cilostazol
One tablet (100 mg) twice per day for 12 weeks
Other Name: Pletaal (brand name)
Placebo Comparator: Dummy Placebo
One tablet twice per day for 12 weeks
Drug: Dummy Placebo
One tablet twice per day for 12 weeks
Other Names:
  • Placebo
  • Control

Detailed Description:
  1. titration of drugs

    1. run-in period: eligible subjects are screened and baseline blood samples are obtained
    2. study period: 12 weeks

      • 24 subjects with cilostazol and 20 subjects with dummy placebo
      • On the first day after the end of the study period, the follow-up data are obtained by the same procedure
    3. blood sampling and measurement of serum biomarkers

      • obtained from peripheral veins in all study subjects at the run-in period and the end of the treatment period of the study
      • sent for isolation, cell culture, and assays of human EPCs
      • also stored for enzyme-linked immunosorbent assay (Stromal cell derived factor-alfa1, adiponectin, soluble thrombomodulin, vascular endothelial growth factor)
  2. assays of human EPCs

    1. colony formation by EPCs
    2. quantification of EPCs and apoptotic endothelial cells
    3. chemotactic motility, proliferation/viability and apoptosis assays
  3. collateral vessels formation and distal run-off assessed by dual-energy multi-slice computed tomography angiography
  4. echocardiographic examinations to evaluate left ventricular functions

Ages Eligible for Study:   20 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • ankle-brachial index (ABI) less than 0.9 in one or both legs but no obvious symptoms of intermittent claudication

Exclusion Criteria:

  • obvious symptoms of intermittent claudication
  • severe PAD (Fontaine grading > 3) or critical limb ischemia in at least one leg
  • severe liver dysfunction (transaminases >10 times of upper normal limit, history of liver cirrhosis, or hepatoma)
  • > stage 4 chronic kidney disease (end-stage renal disease with chronic dialysis not excluded)
  • left ventricular ejection fraction <50% by echocardiography
  • documented active malignancy
  • chronic inflammatory disease
  • planned coronary intervention or endovascular therapy or bypass surgery within 3 months
  • known drug allergy history for cilostazol
  • current use of cilostazol or any other cAMP-elevator
  • premenopausal women
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Please refer to this study by its identifier: NCT01952756

National Cheng Kung University Hospital
Tainan, Taiwan, 704
Sponsors and Collaborators
National Cheng-Kung University Hospital
Department of Health, Executive Yuan, R.O.C. (Taiwan)
Principal Investigator: Ting-Hsing Chao, MD National Cheng-Kung University Hospital
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: National Cheng-Kung University Hospital Identifier: NCT01952756     History of Changes
Other Study ID Numbers: NCKUH-10103043/BR-100-134
Study First Received: September 21, 2013
Last Updated: July 16, 2014

Keywords provided by National Cheng-Kung University Hospital:
endothelial progenitor cells
peripheral arterial disease

Additional relevant MeSH terms:
Peripheral Arterial Disease
Peripheral Vascular Diseases
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases
Bronchodilator Agents
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Asthmatic Agents
Respiratory System Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Vasodilator Agents
Neuroprotective Agents
Protective Agents
Phosphodiesterase 3 Inhibitors
Phosphodiesterase Inhibitors
Enzyme Inhibitors processed this record on April 28, 2017