Heart Attack Medication Does Not Help Repair Muscle Damage

Heart attack patients who receive a medication developed to prompt bone marrow stem cells to repair heart muscle damage have the same outcomes as those who do not receive the treatment, according to a study published on Wednesday in the Journal of the American Medical Association, the Philadelphia Inquirer reports. The study involved 114 heart attack patients who received either Neupogen, manufactured by Amgen, or a placebo (McCullough, Philadelphia Inquirer, 3/1).

Neupogen uses the hormone GCSF to prompt bone marrow to release cells that produce blood into the bloodstream. Previous studies on animals indicated that that the cells would "home in on the damaged heart tissue, transform into heart muscle cells and in effect rebuild the heart," the New York Times reports.

In addition, previous small studies on humans found that heart attack patients who received Neupogen experienced improved heart function, an indication that the treatment "would be the first fruit of the new wave of interest in stem cells," according to the Times (Wade, New York Times, 3/1). However, in the most recent study, German researchers found that participants who received Neupogen had the same level of heart function as those who did not receive the medication, as well as the same amount of damaged tissue and reclogged arteries after six months (Philadelphia Inquirer, 3/1).

Study co-author Dietlind Zohlnhofer said the results of the study "do not prompt optimism and are not supportive of the application of stem cell therapy in patients with heart attacks." She added, "We have to understand more about the basic biology of stem cells before going to new clinical trials."

In an editorial that accompanied the study, Robert Kloner, a cardiologist at the University of Southern California, writes that "some investigators may be disappointed with these results or may try to find fault with the study," adding that "only with such trials will it be possible to differentiate between the hype often generated by smaller, less well-controlled trials and reality." In addition, he writes that he does "not consider this to be a major setback for stem cell research" because other treatments remain untested (New York Times, 3/1).

"It is feasible to rebuild a damaged heart," Kloner said, adding, "I have no question about this. The question is, what is the best way to do it" (Philadelphia Inquirer, 3/1).

The study is available online.