Blood Substitute Safely Reduces Need for Transfusions

A hemoglobin-based oxygen carrier appears to be a safe substitute for blood transfusion, according to results of a multinational, phase III clinical trial among patients undergoing elective orthopedic surgery.

Researchers at the University of California Los Angeles (UCLA, USA) and other institutions conducted a clinical trial that included 688 adults undergoing non-emergency orthopedic surgery at study sites in North America, Europe, and South Africa. Average patient age was 60.8 years, and 57 were more than 80 years old. The patients were randomized to HBOC-201 (350 patients) or packed red blood cells (PRBCs, 338 patients) at the point where a transfusion was deemed necessary. Patients received up to 10 units of the blood substitute during six days post-surgery; beyond this point, patients requiring further transfusion were switched to PRBCs.

The results of the study showed that HBOC-201 eliminated the need for blood transfusion in 59% of subjects; however, there were significantly more adverse events, serious adverse events, and adverse events per patient in the HBOC arm of the trial.
Most of the adverse outcomes involved cardiac and central nervous system events probably related to patient age, volume overload, and undertreatment, and were isolated to patients that could not be managed by HBOC-201 alone. Mortality rates did not differ significantly between the two groups; there were 10 deaths in the HBOC-201 group and six in the PRBC group, none of which the independent reviewers categorized as treatment-related. The researchers concludes that for patients less than 80 years of age and for whom the predicted need for transfusion is no more than three units of PRBCs, HBOC-201 is a safe alternative; however, the blood substitute may not be appropriate for high-risk patients and patients over the age of 80. The study was published in the June 2008 issue of the Journal of Trauma.

"Bridging oxygen delivery needs with HBOC-201 should be considered until blood becomes available,” advised lead author Jonathan S. Jahr, M.D., of the UCLA School of Medicine and colleagues. "When any form of RBC is not an option, treatment with HBOC-201 is appropriate and may be optimal.”

HBOC-201, a product of Biopure (Cambridge, MA, USA) is a purified, cell-free, glutaraldehyde cross-linked and polymerized bovine hemoglobin in a modified lactated Ringer's solution. HBOC-201 can be stored at room temperature for up to 3 years and does not require cross matching.


Related Links:
University of California Los Angeles
Biopure