Despite an adequate and safe blood supply in North America and Europe, the pursuit of an artificial blood substitute remains noble if 3 conditions are met: it is safe, effective, and universally available. In this issue of JAMA, the findings of Natanson and colleagues1 of a clinically important increase in risk of mortality and risk of myocardial infarction across hemoglobin-based oxygen carrier (HBOC) trials cast serious doubt on the first and second conditions, thereby making the third irrelevant. Specifically, based on their analysis of available data, the authors found a 30% increase in the risk of death and nearly a 3-fold increase in risk of myocardial infarction when all HBOC trials were pooled. More troubling, trials continue to be planned and conducted in the presence of accumulating knowledge as demonstrated by the cumulative meta-analyses.
Fergusson DA, McIntyre L. The Future of Clinical Trials Evaluating Blood Substitutes. JAMA. 2008;299(19):2324–2326. doi:10.1001/jama.299.19.jed80027