What is an inhibitor ?
Inhibitors are antibodies that the immune system develops to attack factor IX because it thinks it is a foreign protein. During very early childhood the immune system learns which proteins are supposed to be in the body. If a person has no factor IX or has a very different form of factor IX, the immune system never learns what normal factor IX looks like. Then when a boy with hemophilia B is infused with factor IX concentrate, the immune system may think it is an invading, foreign protein that it needs to fight off. The inhibitor interferes with the function of the factor IX protein keeping it from restoring the clotting ability of the blood. Now that infectious disease transmission from factor concentrates is no longer a major issue, inhibitor development is the biggest problem in hemophilia treatment. Fortunately, only about 2 – 3 % of hemophilia B patients develop inhibitors. However, for those that do develop an inhibitor, it is a serious consequence. In addition, about 50 % of hem
Inhibitors are antibodies to the coagulation product (i.e. factor VIII or IX) that attack and destroy factor VIII or IX proteins in clotting factor concentrates, thus making the treatment ineffective. In other words, the body rejects the newly infused factor product. Approximately 15% of people with severe Hemophilia A will develop inhibitors at some time. Inhibitor development in Hemophilia B is very rare, less than 1%. Inhibitors emerge after just a few treatments. In general, the more treatments a person had without developing inhibitors, the less likely he is to develop an inhibitor. Where can I find more information on Hemophilia? Local and state Hemophilia chapters, The Hemophilia Federation of America (www.hemophiliafed.org) and The National Hemophilia Foundation (www.hemophilia.org) all provide educational information on Hemophilia.
Inhibitors are antibodies that the immune system develops to attack factor IX because it thinks it is a foreign protein. During very early childhood the immune system learns which proteins are supposed to be in the body. If a person has no factor IX or has a very different form of factor IX, the immune system never learns what normal factor IX looks like. Then when a boy with hemophilia B is infused with factor IX concentrate, the immune system may think it is an invading, foreign protein that it needs to fight off. The inhibitor interferes with the function of the factor IX protein keeping it from restoring the clotting ability of the blood. Now that infectious disease transmission from factor concentrates is no longer a major issue, inhibitor development is the biggest problem in hemophilia treatment. Fortunately, only about 2 – 3 % of hemophilia B patients develop inhibitors. However, for those that do develop an inhibitor, it is a serious consequence. In addition, about 50 % of hem
