Stem cells with heart bypass surgery trial to begin

Aug 25 2005

The University of Pittsburgh Medical Center (UPMC) has been granted approval by the U.S. Food and Drug Administration (FDA) to conduct a clinical trial to determine the safety and feasibility of injecting a patient's own bone marrow-derived stem cells directly into the heart during conventional heart bypass surgery.

The trial will involve patients with ischemic heart disease who are scheduled for off-pump (beating heart) coronary artery bypass grafting surgery. In addition to assessing the safety and feasibility of using a patient's own stem cells as a potential therapy for heart disease, researchers also will be trying to determine just how many stem cells are needed to produce the best results.

Patients who give their consent to participate will be randomized to one of four treatment groups and neither they nor the researchers will know into which group they are assigned until the conclusion of the study. Researchers hope to enroll a total of 24 patients - six in each group - who they will follow over the course of one year.

In May, UPMC was given clearance by the FDA to conduct a similar trial in patients needing heart assist devices as a bridge to organ transplantation. Both studies are being directed by Amit Patel, M.D., M.S., director of the Center for Cardiac Cell Therapy at UPMC and the University of Pittsburgh McGowan Institute for Regenerative Medicine.

"Stem cell therapy as an adjuvant to traditional bypass surgery is the next step to help determine the best way to help very sick heart failure patients. This is the first randomized study in the U.S. to evaluate the combination of cell therapy with traditional surgical revascularization and may help answer a number of key questions," explained Dr. Patel, an assistant professor of surgery in the division of cardiothoracic surgery, University of Pittsburgh School of Medicine.

"Standard surgical and catheter-based treatments are reasonably effective for treating chest pain, reducing the risk of heart attack and improving heart function. But none has the ability to actually restore or repair damaged heart tissue. The aim of stem cell therapy is to repopulate the ailing heart muscle with cells that may help restore blood supply and help the heart regain its ability to contract more effectively and efficiently," added Joon S. Lee, M.D., clinical director of UPMC's Cardiovascular Institute and assistant professor of medicine and associate chief, division of cardiology, University of Pittsburgh School of Medicine.

Various studies that have been conducted around the world, including a limited number performed in the United States, have suggested that when patients with heart failure receive stem cells taken from their bone marrow, their hearts show signs of improved function and recovery. However, most of these clinical studies did not control for variables that may have influenced patients' clinical improvements, and all but a very few were designed as a randomized and double-blinded trial, the most rigorous method for evaluating clinical interventions.

UPMC researchers expect to ask about 75 patients to participate in the new trial in order to enroll and randomize six patients into each of the four study groups. A person not involved in the study will select a card from 24 numbered one through four to determine which group a patient is to be assigned. Then, with the patient under anesthesia, Dr. Patel's team will harvest bone marrow from the patient's hipbone. While the bypass operation is taking place, the patient's stem cells will be isolated from the bone marrow and prepared accordingly, depending on the patient's random assignment. Patients may be randomly selected to one of three groups that will receive varying concentrations of stem cells or to a fourth group receiving their own blood serum void of stem cells.

According to the American Heart Association, nearly 13 million Americans have coronary artery disease. Despite medical advances, coronary heart disease results in about 500,000 deaths each year.