Editor's Note: Author is the CEO of Pluristem
Every year, approximately 800,000 patients in the USA suffer from an acute myocardial infarction that results in sudden death, chronic, recurrent, chest pain or cardiac pump failure. The basic problem involved in the vast majority of these patients is the build up of cholesterol in the wall of the coronary artery, preventing an adequate amount of blood from reaching cardiac muscle cells. This is termed coronary artery disease (CAD) and it is estimated that 13 million Americans suffer from this disorder. Patients with CAD who experience chest pain are said to be suffering from angina, a situation where cardiac muscle cells are in desperate need of more blood.
Additionally, the heart may suffer from cardiac failure when the heart's primary function as a pump for moving blood throughout the circulatory system is impaired due to the fact that the "pump" is not getting enough blood. Risk factors for CAD include high blood pressure, hypercholesterolemia, obesity, and diabetes. Surgical procedures such as coronary by-pass surgery, angioplasty and stenting have become commonplace in the treatment of CAD. Additionally, pharmacologic therapy with nitrates that dilate the coronary arteries, digitalis that improves the efficiency of the heart as a pump and statins that reduce our body's cholesterol burden, are also commonly used. None of these therapies stimulate the growth of new blood vessels into the heart, allowing more blood to get to cardiac muscle cells starved for blood.
However, researchers using stem cells developed by Pluristem Therapeutics (NASDAQ:PSTI), may have discovered a unique and different way of attacking CAD. Pluristem's placental-derived cells have been shown to not only stimulate the formation of new vessels into blood-deprived tissue, but have also demonstrated that these cells secrete potent anti-inflammatory proteins that help protect cells from dying until an adequate blood supply can be restored.
Pluristem, an American company with headquarters in Haifa, Israel, is a cell therapy company that obtains and manufactures its products from cells derived from the placenta. The placenta, or after-birth, is an organ commonly thought of as medical waste to be disposed of after childbirth. Pluristem believes these non-controversial cells, located in the body of the placenta and termed adherent stromal cells (ASCs), are potent secretors of anti-inflammatory and cell-protecting proteins in addition to proteins that stimulate the formation of new blood vessels. The company grows these ASCs in a proprietary three dimensional (3D) technology that allows for a very efficient production of their final product, termed PLacental eXpanded (PLX) cells. The efficiency of Pluristem's 3D expansion technology is so robust that 10,000 doses of PLX cells can be produced from one placenta at a fraction of the cost to grow cells in petri dishes or tissue flasks, which is the industry norm. Additionally, PLX cells can be available "off-the-shelf" and be administered without the PLX cells needing to be tissue-matched to the patient.
Because of the unique anti-inflammatory and cell-protecting properties that PLX cells possess, Pluristem initially began testing these cells in patients afflicted with peripheral artery disease (PAD). Although Pluristem is continuing to conduct clinical trials using PLX cells in PAD, the preliminary results of these trials suggested these cells were so effective in improving PAD that we felt the next logical step would be to test PLX cells for the treatment of CAD in an attempt to improve heart function.
Recently, Pluristem announced the results of testing PLX cells for the treatment of two different models of heart disease. The research was done in collaboration with physicians at the Charite Universitaetsmedizin Berlin, Berlin-Bradenburg Center for Regenerative Therapies, Berlin, Germany.
In the first experiment, animals were subjected to open heart surgery and a major artery feeding the main pumping part of the heart was tied off, causing the animal to suffer a heart attack. One half of the animals then received PLX cells while the other half received saline (salt water) as a control. PLX cells or saline was administered directly into the area of the heart where the heart attack occurred. Twenty-eight days later, the animal's cardiac function was measured. There was an improvement in all of the cardiac functional parameters measured in those animals given PLX cells versus those given saline. These included important measurements such as the amount of force the heart generated to pump blood into circulation as well as the amount of blood ejected with each heartbeat. The microscopic analysis of the heart showed a significant reduction in the size of the heart attack and an increase in the number of new blood vessels forming in the heart in those animals given PLX cells versus controls.
Armed with these exciting, favorable results, the researchers at the Charite then administered PLX cells or saline in diabetic animals with heart failure. One-half of the diabetic animals were given PLX cells, with the other half receiving saline intravenously. The animal's cardiac function and the degree of heart inflammation were measured 21 days later. As in the first experiment, there was a significant improvement in the cardiac function in those animals receiving PLX cells versus those given saline. Additionally, there was also a significant reduction in the inflammation of the heart tissue in those animals receiving PLX cells versus saline.
As we have discussed on numerous occasions, Pluristem's strategy is to develop a minimally invasive cell therapy solution that can be used to treat a wide range of life-threatening diseases. The initial testing of a PLX cell treatment for heart disease opens a new potential indication where PLX cells can be used, positioning Pluristem as a "first-line of defense" for numerous cardiac diseases. Pluristem's placenta-derived stem cell therapy has an opportunity to impact the world, and it is important for the Company's community of patients, doctors and shareholders to be clear that not only is Pluristem working toward something significant, but also as the Company moves into the treatment of new indications, we are successfully executing on our strategy.
Disclosure: I am long PSTI. I am the CEO of Pluristem.