Blood Substitutes

Links

Introduction

History of Blood Substitutes

Hemopure®

Oxyglobin®

PolyHeme®

Hemospan®

Dextran-Hemoglobin

Oxygent®

Emerging Ideas - Dendritech®

Does the Future Rest on Stem Cells? - Interview with Dr. Narla

Credits

 

“If this really works all the way, then mankind will have taken a big step forward. This is like landing on the moon."

-Dr. Pierre LaFolie

 

What is artificial blood?

The term artificial blood is somewhat misleading – no one product is being designed to replace the function of human blood. Blood substitute technology is separated into two main categories – volume expanders which only increase blood volume, and oxygen therapeutics, which substitute for the blood’s natural ability to carry oxygen. This page focuses on oxygen therapeutics, and the new, emerging research in this field.

 

Why do we need blood substitutes?

1. Increasing Demand

About 14 million units of blood were used last year in the United States alone. According to Dr. Bernadine Healy, former president of the American Red Cross, donations are increasing by about 2-3% annually in the United States, but demand is climbing by between 6-8% as an aging population requires more operations that often involve blood transfusion. New York City currently relies on Europe for 25% of its blood supply. Shortages frequently cause delays in elective surgeries, and this problem is only increasing. According to Dr. Healy “Artificial blood would be a blessing.” Additionally, in the case of a major disaster current blood supply and donation efforts could be insufficient

2. Developing Nations

Although the blood supply in the US is very safe, this is not the case for all regions of the world. 10-15 million units of blood are transfused each year without testing for HIV or hepatitis. Blood transfusion is the second largest source of new HIV infections in Nigeria. In certain regions of South Africa as much as 40% of the population has HIV/AIDS, and thorough testing is not financially feasible. A disease-free source of blood substitutes would be incredibly beneficial in these regions. Hemopure is currently approved for use in South Africa, largely because it is a major improvement over the blood supply in this region.

 

3. The Armed Services

The first research into producing blood substitutes was conducted by the United States Army following the Vietnam War. In battlefield scenarios it is often impossible to administer rapid blood transfusions, and it is difficult to maintain a safe and adequate blood supply. Medical care in the armed services would benefit from a safe, easy to manage blood supply. Hemospan can be dried and transported as a powder, stored for years, and then reconstituted as liquid before transfusion. This would have tremendous implications for the military as it would be very easy to administer, available in large quantities, and does not require typing. The Armed Services have a vested interest in the success of blood substitute technology.

Current Military Funding to Date
Biopure-(Hemopure) $22.5 million
Northfield - (Polyheme) $5 million
Sangart $1.3 million *
Dendritech $750,000

*Joint grant from The National Heart Lung and Blood Institute, The National Institutes of Health, and The United States Army Medical Research and Material Command

 

4. Rapid Treatment

Even outside of military applications, great benefit could be derived from the rapid treatment of patients in trauma situations. Because these blood substitutes do not contain any of the antigens that determine blood type, they can be used across all types without immunologic reactions. This would eliminate time spent on testing and cross-matching that ordinarily needs to occur before all blood transfusions.

5. Is it safer?
Although transfused blood in the US is very safe, with between 10 and 20 deaths per million units, blood substitutes could eventually improve on this. Within two weeks of HIV infection test results may be negative, as antibodies may not have formed. Nucleic Acid Testing to identify HIV infection before antibody formation may be prohibitively expensive in some nations. In addition, there is no practical way to test for prion transmitted diseases, such as Mad Cow and Creutzfeldt-Jacob disease, and other diseases could emerge as problems for the blood supply, including Smallpox and SARS.

6. Could it be cheaper?

Current estimates of the costs of blood substitues range between 300 and 1000 dollars. The current cost of a unit of blood varies by region, but the highest current cost is about $200. Although this might seem to clearly suggest that transfused blood is more cost effective, there are many reasons to believe this may change.

    • The cost of blood substitutes will fall as manufacturing becomes refined
    • Most don’t require any sort of storage or administrative costs. These storage and administrative costs with transfused blood are passed along to the patient, making the real cost of a unit of transfused blood approximately 500 dollars
    • Studies conducted by Biopure, which estimate that it will charge $1000 for its product in the US if it comes to the market, suggest that only one unit of the substitute would be required compared to two or three units of transfused blood, making the price increase less significant
    • The cost of transfused blood will only increase as further tests are administered to ensure a safe blood supply