Used in the treatment of thromboembolic disorders for the lysis of pulmonary emboli, arterial thrombus, deep vein thrombus and acute coronary artery thrombosis. An enzyme obtained from cultures filtrates of beta hemolytic, streptococci group C. Has the property of activating human plasminogen to plasmin. Available as a sterile, friable solid or white powder. The activity is due to activation of plasminogen to a proteolytic enzyme namely plasmin which degrades fibrin clots, fibrinogen and other plasma proteins.