What is alteplase?

Formerly known as tissue plasminogen activator or tPA is a serine protease originally derived from cultured human melanoma cells. It is now obtained as a product of recombinant DNA technology. Reteplase is a genetically engineered, smaller derivative of recombinant tPA. Alteplase has a low affinity for free plasminogen in the plasma, but it rapidly activates plasminogen that is bound to fibrin in a thrombus or a hemostatic plug. Thus, alteplase is said to be “fibrin selective” at low doses. Alteplase is approved for the treatment of MI, massive PE, and acute ischemic stroke. Alteplase has a very short half-life (5 to 30 minutes), and therefore, 10% of the total dose is injected intravenously as a bolus and the remaining drug is administered over 60 minutes