Blood Transfusion Alternative
Experimental Drug May Replace Human Blood Transfusions
Oct. 14, 2002 -- An experimental drug derived from cow blood may provide a life-saving alternative to human blood transfusions. New research shows the oxygen-carrying drug can be a safe and effective short-term replacement for donated human red blood cells during surgery.
Blood shortages across the U.S. have become increasingly acute in recent years, and this year at least one major hospital has been forced to cancel scheduled surgeries due to a lack of blood supply.
Researchers say the experimental drug, known as polymerized bovine (cow) hemoglobin or HBOC-201, can help keep people stable during and after surgery and ease the demand for human red blood cells by postponing transfusions or even making them unnecessary.
Unlike stored human blood, the drug also has several practical advantages. It's compatible with every blood type, does not require refrigeration, remains stable for three years, and potential infectious agents are removed during the manufacturing process.
In this phase III clinical trial, researchers compared the effectiveness and safety of HBOC-201 with that of donated red blood cells in about 700 orthopaedic surgery patients. More than half of the HBOC-201 patients were able to avoid a blood transfusion.
There were no significant abnormalities or problems in the group that received the experimental drug compared with those who got red blood cells. The most commonly reported side effect of HBOC-201 was a superficial yellow skin discoloration. Other side effects were mild and limited, the researchers say.
The drug is delivered intravenously and uses purified cow hemoglobin (the oxygen-carrying pigment found in red blood cells) to improve oxygen flow in the patient's tissues. Researchers say the bovine hemoglobin molecules are small, allowing them to flow better in the blood vessels and deliver oxygen even more efficiently than human red blood cells.
But the researchers say it's not a matter of being more effective than human blood.
"HBOC-201 effectively provides an oxygen 'bridge' that helps keep acutely anemic patients stable during and after surgery," says study author Jonathan S. Jahr, MD, director of clinical research at UCLA, in a news release. "It can also fill an unmet medical need when compatible red blood cells are not readily available or when there is a need of preference to avoid blood transfusions."
Jahr presented the findings today at the annual meeting of the American Society of Anesthesiologists.
The drug is already approved for use in South Africa, and an application for use in orthopaedic surgery in the U.S. has been filed with the FDA.
Jahr says HBOC-201 may also be useful in treating sickle cell disease, cancer, and trauma patients. Since the drug can be stored at room temperature, Jahr says it may prove especially useful in treating patients outside the hospital, such as on the battlefield or at the scene of auto accidents.