Transplanted Skeletal Muscle Cells Restore Heart Function
Skeletal muscle cell transplantation into the myocardium of heart failure patients appears to be safe and to show signs of efficacy, French researchers reported Wednesday at the 6th International Congress of the Cell Transplant Society.
In a phase I trial, Dr. Jean Thomas Vilquin with the INSERM and University Hospital, Paris, and colleagues treated 10 male patients who had refractory chronic heart failure. The patients had a mean age of 60.3 years and New York Heart Association functional class II-IV. The mean left ventricular ejection fraction (LVEF) was 24%, and all patients were candidates for coronary artery bypass grafting (CABG).
A muscle biopsy was taken from each patient. The cells were then processed and delivered by direct injection to the heart.
The trial showed feasibility of cell production, tolerance of biopsy and injection, and indications of efficacy, including regional contractility and improvements in perfusion, Dr. Vilquin reported.
Global left ventricular function increased significantly after transplant compared to baseline (p < 0.02), and 14 out of 22 scarred cell transplant segments showed contractility after transplant compared with no contractility before transplantation. “Our phase I trial indicates that it is possible to produce a large amount of cells in a short time course,” Dr. Vilquin told Reuters Health “that the injections and the biopsy are safe, and the first indications of efficacy are very promising.” Dr. Vilquin noted during his presentation that the relative contributions of CABG and cell transplantation, the ultimate impact on quality of life, and the cause of arrhythmias are issues that still need to be addressed. Four patients experienced arrhythmias that were not anticipated during the study. “These can be controlled, and we have changed the design of the upcoming phase II study to account for this,” he noted. The first phase II clinical trial for this procedure is now underway. The study, to be sponsored in part by Genzyme Corporation, will aim to recruit 300 patients. The endpoints will be contractility of kinetic myocardial segments, major adverse cardiac events, left ventricular function, quality of life and dose effect. “We are also looking at patients with other cardiomyopathies, such as dilated heart and pathologies not involving infarction,” he added. “So we may be able to enlarge the possible number of patients that may benefit from this procedure.”
