Results from a Trial of a Cell Therapy for Heart Failure

Results were recently published for a trial of ixmyelocel-T, a therapy consisting of the delivery of a mix of cell types generated from a patient sample, including mesenchymal and immune cells. This produced modestly promising results in a trial for limb ischemia a few years back, and here the focus is on heart failure, with a similar modestly promising outcome. To take a glass half empty view, the results suggest that in advanced cases of disease the present generation of regenerative therapies are too little, too late. Far greater rebuilding and reconstruction will be needed to do more than slow the decline, but equally these same present generation therapies would no doubt achieve more if used earlier and more often in the disease process, all the way back to preclinical stages. That would require something of a paradigm shift in the way mainstream medicine is practiced, however. The idea of treating people for prevention with therapies of this sort is not yet a popular one, sad to say, and the state of regulation makes it hard to start down that path within the bounds of the system.

Among 109 patients randomized to receive the cell therapy or a placebo, those receiving the cell therapy, which involved extracting stem cells from a patient's own bone marrow, showed a 37 percent lower rate of the trial's primary endpoint, a composite of deaths, cardiovascular hospitalizations and clinic visits for sudden worsening of heart failure symptoms, over a 12-month period. "To date, this is the largest double-blind, placebo-controlled stem cell trial for treatment of heart failure to be presented." The study was a phase 2 clinical trial for a new stem cell therapy known as ixmyelocel-T. Using this technique, a doctor extracts a sample of bone marrow from a patient, processes it for two weeks to "enhance" it by increasing the number of beneficial stem cells, and then injects the processed bone marrow product into the same patient's heart muscle. The goal of the procedure is to strengthen the heart by increasing the number of functioning heart muscle cells, an approach known broadly as regenerative therapy.

The trial enrolled 109 patients with class III or IV heart failure resulting from ischemic cardiomyopathy, a type of heart failure that is related to restricted blood flow from a heart attack or coronary artery disease. Roughly half, 58 patients, were randomly assigned to receive intramyocardial ixmyelocel-T treatment, and 51 patients were assigned to receive a placebo. Patients in the control group underwent a bone marrow extraction and received a placebo injection two weeks later. Among patients given stem cell therapy, 3.4 percent died and 37.9 percent were hospitalized with cardiovascular problems, as compared to 13.7 percent and 49.0 percent, respectively, in the placebo group. Patients given stem cell therapy also had, on average, a longer amount of time until their first adverse event. Other measures of heart function and quality of life, including a walking endurance test and a measurement of the amount of blood pumped out of the left ventricle with each contraction, also suggested improvements in the group receiving ixmyelocel-T.

Link: http://www.eurekalert.org/pub_releases/2016-04/acoc-sct040416.php