ATryn is used in patients who have congenital antithrombin deficiency (inherited low levels of the protein antithrombin). Antithrombin is a glycoprotein produced by the liver and consists of 432 amino acids that inactivates several enzymes of the coagulation system. It is used when the patients are having surgery, to prevent problems due to the formation of blood clots in the vessels. In the body, antithrombin blocks thrombin, a substance that plays a central role in the process of blood clotting. Patients who have congenital antithrombin deficiency have low blood antithrombin levels, which may result in a reduced capacity of the blood to resist clotting. This increases the risk of clots forming during high-risk situations. ATryn corrects the
