FDA approves new test for finding blood compatibility

The U.S. Food and Drug Administration today approved a new test for finding blood compatibility. It is the second molecular assay approved for use in transfusion medicine, and the first to report genotypes as final results.

It is basically a molecular-based assay by the name ID CORE XT, that can be used to help determine blood compatibility and blood donor and patient non-ABO red blood cell (RBC) types.

Human blood can be classified into different groups based on the antigens on the surfaces of red blood cells. It is a general principle that red cell components of identical ABO group and RhD type as the recipient should be used for transfusion. O Rh-negative is the universal red cell donor blood that can be given to all patients. This is common practice when a patient’s blood group is unknown and in emergency situations especially for women of child-bearing age.

In addition to the ABO blood group antigens, the presence or absence of other specific blood group antigens can be important when matching blood for transfusions since some people develop antibodies to non-ABO antigens. People who receive repeated blood transfusions, such as individuals with sickle cell disease, are more likely to develop these antibodies. If red blood cells with poorly matched non-ABO antigens are transfused, red blood cell destruction and a transfusion reaction can occur in a transfusion recipient.

Such serological incompatibility is important because transfusion of incompatible blood can kill people. In fact, acute intravascular hemolytic reactions due to ABO incompatibility of the donor and recipient are the leading preventable cause of transfusion-related death.

"The approval of the ID CORE XT Test can streamline blood compatibility testing and provides an additional alternative to testing blood with antisera," said Peter Marks, M.D., Ph.D., M.D., director of the FDA's Center for Biologics Evaluation and Research. "We know that DNA testing holds great promise – to provide more informative, accurate and cost-effective methods that can enhance patient care."

Traditionally, red blood cell antigens have been identified using serological methods that involve the use of antisera, a blood serum that contains antibodies for testing. Serologic testing presents limitations and certain antisera may be scarce or unavailable.

Prior to FDA-approved of the first molecular assay and DNA sequencing tests, a study was conducted to compare the typing results of the ID CORE XT Test with licensed serological reagents in which the results demonstrated comparable performance between the methods.