The authors conducted a study on the safety of hemoglobin glutamer
-250 in surgical patients. The protocol consisted of exposing (different) patients to increasing doses of hemoglobin glutamer-250 while safety was monitored. Control patients received Ringer’ lactate solution. The results are not unexpected. Basically, in these patients who bled on average 1.7 L during surgery, hemoglobin glutamer-250 was well tolerated, albeit all three serious adverse events reported occurred in patients receiving the oxygen carrier. Transfusion requirements were not different between groups at any time. Interestingly, reticulocyte counts were increased on postoperative
day 7 in the hemoglobin glutamer-250 group. However, despite elevated total iron concentrations (as expected), this effect on erythropoiesis did not translate in any apparent clinical benefit since total hemoglobin concentrations were strictly similar between groups. While such studies are essential prerequisites to the safe use of these drugs, they do little to convince clinicians that oxygen carriers are associated with true clinical advantages, i.e. that they reduce the need for allogeneic transfusions.

– J.-F. Hardy.