BACKGROUND: Buerger’s disease, thromboangiitis obliterans, is a rare disease of the arteries and veins in the arms and legs. The blood vessels become inflamed, swell, and can become blocked with blood clots (thrombi). Eventually skin tissues will get destroyed and may lead to gangrene and infection. As Buerger’s disease develops, it will show in the feet and hands first. It can eventually affect larger areas of the legs and arms. Buerger’s disease is rare in the United States, but is more common in the Middle and far East. It usually affects men who are younger than 40. However, it is becoming more common in women. Almost everyone who is diagnosed with Buerger’s disease smokes cigarettes or used other forms of tobacco. (Source: www.mayoclinic.com)
TREATMENT: Treatment can not cure Buerger’s disease. Doctors say the most effective way to stop the disease’s progress is to quit using tobacco products. Doctors can recommend non-nicotine medications that can be used to help the patient stop smoking and stop the swelling. Another option is a residential smoking cessation program, which is similar to a rehabilitation program. Other treatment options exist, but are less effective. (Source: www.mayoclinic.com)
NEW TECHNOLOGY: Biomet, Inc., a global manufacturer of orthopedic and biotechnology products, and its subsidiary, Biomet Biologics, sponsored the Phase I clinical trial of MarrowStim™ investigational device for individuals with critical limb ischemia. Critical limb ischemia (CLI) is a severe blockage in the arteries of the lower extremities, which markedly reduces blood-flow. It is a serious form of peripheral artery disease (PAD). MarrowStim™ utilizes the body’s own concentrated bone marrow to possibly improve blood flow in legs with blocked arteries by attempting to create new blood vessels. The procedure involves removing bone marrow from the hip bone and transferring it to the investigational device for processing and concentration. Once it is processed, the marrow is injected into the affected limb. The marrow contains mononuclear cells that may have the potential to treat diseased vascular structures. Doctors believe this treatment could help many people with circulation problems, like Buerger’s disease and PAD.
The trial was performed under an FDA-approved Investigational New Drug (IND) Application to evaluate the safety of autologous concentrated BMA therapy in 29 “no option” CLI subjects who were at risk for major amputation due to severe PAD. The results included: no reports of procedure-related deaths; two reports of procedure-free survival rate of 86.3%; improvement in rest pain, quality of life, and perfusion measures at 12 weeks after treatment; and overall average procedure time of less than two hours. Biomet Biologics advanced the MarrowStim™ technology into a multicenter trial under an FDA-approved Investigational Device Exemption (IDE). The trial will enroll a total of 152 patients and is currently ongoing at 14 investigational sites. Study participants will be randomized to either receive MarrowStim™ treatment or placebo, 75% will get MarrowStim™ and 25% of patients will receive placebo. Enrollment began in June 2010 and is estimated to end in May 2013, with completion of one-year data collection in May 2014. (Source: www.reuters.com) For enrollment information go to: http://clinicaltrials.gov/ct2/show/NCT01049919?term=biomet+pad&rank=1 or call: (877) 788-3972
Omaida Velazquez, MD, Chief of the Division of Vascular and Endovascular Surgery at The University of Miami Miller School of Medicine, talks about stem cell therapy to improve circulation.
Is Derrick the only patient so far in your clinical trial for this stem cell research?
Dr. Velazquez: He is one of our early patient enrollments and Derrick was the first patient we treated.
He has Buerger’s disease. What is that?
Dr. Velazquez: Buerger’s disease is a disease of the small vessels of the lower extremity that is associated with smoking. Another name for it is thromboangiitis obliterans, which literally means that the blood vessels disappear and they start disappearing from the foot up. It is a process of disease that is more common in men than women and that is almost always associated with smoking. In many patients once they realize they have it, they stop smoking; the disease will become quiet and it does not progress. However, sometimes by that time, there is enough damage and enough of those tiny blood vessels that have withered away and disappeared that the leg ends up with a severe shortage of circulation into the foot, a situation that we call critical limb ischemia. It has no cure. It is a very difficult disease that affects the quality of life of people and may result in the loss of the leg for the individuals that suffer from it.
What was Derrick’s condition? He was having trouble walking and he had pain?
Dr. Velazquez: Derrick was having pain, numbness, and lack of sensation in his foot. He was really being affected. His quality of life was significantly affected by these symptoms. When we looked at the circulation in his foot and his big toe, it was severely decreased, which made us concerned that he may end up losing tissue in that leg and become at risk for an amputation.
What will the clinical trial do for him? What did you do? You took stem cells from his hip?
Dr. Velazquez: So, the clinical trial involves exactly that. It involves obtaining the stem and progenitor cells of Derrick’s own bone marrow and we use the hip as a bone marrow donor site. That is a common bone marrow donor site. It is the same site that volunteers donate their bone marrow for other patients use in order to make their donation. So, we took the bone marrow from Derrick’s iliac crest and we run it through a machine made by Biomet Biologics. Basically we extract a fraction of the cells that are there, some of the cytokines, and factors that come with those cells, and we inject that fraction into the patient’s own leg in the muscle compartment up and down the leg in the affected area.
Then what happens? New vessels grew because of the stem cells?
Dr. Velazquez: That is the intended and believed mechanism. We all walk around with these repair cells. Some people call them rejuvenating cells in our own bone marrow. In other sites of our body too, but the bone marrow is rich in these repair cells. Sometimes they just do not know where to get to repair and what this new treatment does is it takes the bone marrow sample, extracts that fraction that is rich in this progenitor and stem cells that are rejuvenating or repairing, and it puts them where they need to be; where the lack of blood vessels is taking place. It is believed that these cells then release some growth factors and proteins that help in regeneration of blood vessels and other types of pro-repair functions that lead to an improvement in the circulation to the leg and to the foot.
This trial is also for peripheral vascular disease. Can you explain what that is?
Dr. Velazquez: Peripheral vascular disease is very common. Peripheral vascular disease is a manifestation of what we call atherosclerosis, which is buildup of plaque, cholesterol, calcium, and lipids inside the arterial tree. They are the blood vessels that feed all the organs. That disease can manifest itself in the heart with a heart attack, in the legs with peripheral arterial disease, pain in the leg, wounds of the leg, gangrene in the leg, and ultimately needing amputation. It can even manifest itself in the neck, in the carotid arteries, causing strokes. So, atherosclerosis is the number one killer in the United States, the western world and absolutely an epidemic in Asia. So, it affects literally millions of people in our planet. Peripheral vascular disease is a manifestation of atherosclerosis. It is very common.
This is going to help millions of people?
Dr. Velazquez: Absolutely.