Autologous Stem Cell Therapy Repairs Cardiac Muscle Damage After Heart Attack
Most people know that I am a big fan of funding the development of stem cell therapies. So when I came across this recent study in The Lancet, I had to talk to Eduardo Marbán, director of the Cedars-Sinai Heart Institute in Los Angeles, Calif., to learn more. Marbán and his colleagues wanted to see if they could replace heart muscle that was damaged by a heart attack with healthy, living cardiac muscle tissue using heart-derived stem cells, and they were successful.
According to Marbán this has never been accomplished before. “People have been trying for about 11 years to use cells of various kinds to treat patients that have sustained damage to the heart muscle from heart attacks,” he said, and there has been some success, but an increase in living heart muscle has never been accomplished.
Marbán and his team found that one year after receiving stem cell therapy, scar size was reduced from 24 percent to 12 percent of the heart in patients treated with stem cells, while patients in the control group, who did not receive stem cells, did not experience a reduction in their heart attack scars.
The study is called the CArdiosphere-Derived aUtologous Stem CElls to reverse ventricUlar dySfunction (CADUCEUS) trial. The researchers started with very small samples taken from a patient’s own heart during a minimally invasive biopsy, using a catheter and a technique that was originally developed to monitor transplant patients for rejection, but had never been used to make a therapeutic agent.
The scientists took the biopsied tissue to the lab and, using methods that they developed, were able to multiply the cells in a petri dish. When they got to the right dosage, either 12.5M or 25M depending on patient assignment, they would call the patient back and readminister the cells via the same coronary artery that had been blocked in the heart attack, using another minimally invasive catheter procedure.
Of the 25 patients enrolled in the study, 8 were randomly assigned to receive standard of care, and comprised the control group, and the others were assigned to receive the experimental stem cell therapy. “The reason we did a randomized study was to be certain that the effects that we were seeing were the result of the therapy, as opposed to just the natural history of the disease,” Marbán said.
He went on to say that he and his colleagues were very encouraged by these phase 1 results. They plan to further study this technique with a view to satisfying the regulatory agencies, particularly the U.S. Food and Drug Administration. The next phase, a 200 patient trial, will be a phase 2 study to further develop this therapy.
Looking Down the Road
“Right now, I think it is safe to say that no cell therapy product will imminently be available worldwide for a fee,” Marbán said. He continued by saying that he thinks that this study will have the effect of increasing the number of clinical trials. “I think that others, encouraged by this work, will look to apply either these same cells, or some other cell type, to treat not only heart attack patients, but patients with other kinds of heart disease.”
Marbán also said that the current study may increase the pace of development for cellular therapies that are already in the pipeline. “I think that if we look five years down the road, at least one, if not two or three cell therapy products will be available. I think that cell therapies are going to make a big difference, particularly in reversing injury, rather than in preventing it.”