Thrombolytic agent streptokinase

Alteplase has proven effective in the early treatment of patients with acute myocardial infarction (i.e. those treated within 12 h after the first symptoms occur). Significantly increased rates of patient survival (as measured 1 day and 30 days after the initial event) are noted when tPA is administered in favour of streptokinase, a standard therapy (see later). tPA has thus established itself as a first-line option in the management of acute myocardial infarction. A therapeutic dose of 90-100 mg (often administered by infusion over 90 min) results in a steady-state alteplase concentration of 3-4 mg l 1 during that period. However, the product is cleared rapidly by the liver, displaying a serum half-life of approximately 3 min. As is the case for most thrombolytic agents, the most significant risk associated with tPA administration is the possible induction of severe haemorrhage. 

Streptokinase is a widely employed thrombolytic agent. It is administered to treat a variety of thrombo-embolic disorders, including ... 

Banerjee, A., Chisti, Y., and Banerjee, U.C. 2004. Streptokinase - a clinically useful thrombolytic agent. Biotechnology Advances 22(4), 287-307. 

Human recombinant tPA and streptokinase are used as thrombolytic agents e.g. they are infused into the bloodstream as soon as possible after a heart attack. 

Banerjee A, Chisti Y, Banerjee UC. Streptokinase -a clinically useful thrombolytic agent. Biotechnol Adv 2004 22 287-307. 

Concomitant use with thrombolytic therapy Clinical trials in HIT patients have provided only limited information on the combined use of lepirudin and thrombolytic agents. The following dosage regimen of lepirudin was used in 9 HIT patients in the studies who presented with TECs at baseline and were started on both lepirudin and thrombolytic therapy (alteplase, urokinase, or streptokinase). 

Plasminogen, an inactive precursor, is activated to plasmin which as a protease is able to break down fibrin clots. The thrombolytic agents in use promote the conversion of plasminogen to plasmin at the site of a thrombus. Indications include post-myocardial infarction treatment. The thrombolytic must be administered within 6 hours for an optimal effect. Other indications are treatment of acute pulmonary thromboembolism, deep-vein thrombosis, acute arterial thrombosis and thromboembolism, as well as in the clearance of arteriovenous catheters and can-nulae. Agents are streptokinase, anistreplase, urokinase, alteplase, reteplase and tenecteplase. 

The major toxicity of all thrombolytic agents is hemorrhage. Streptokinase can cause allergic reactions with fever, rash and, although rarely, anaphylaxis. 

F. Role in therapy Reteplase is a novel thrombolytic agent. It has a longer half-life than alteplase, which allows bolus administration. Its administration technique is much simpler than that of alteplase. In addition reteplase has achieved more rapid, complete, and sustained thrombolysis of the infarct-related artery compared to standard doses of alteplase with comparable safety. Reteplase is at least as effective as streptokinase and alteplase in AMI. 

E Role in therapy Thrombolytic agents currently licensed for the treatment of AMI in the United States include streptokinase, tissue plasminogen activator, anistreplase, reteplase, and tenecteplase. TNKase and alteplase have similar clinical efficacy for thrombolysis after myocardial infarction (i.e., similar mortality and intracranial hemorrhage rates). However, advantages of TNKase include ease and rapidity of administration, longer half-life, greater fibrin specificity, and lower noncerebral bleeding rates. Reteplase shares some characteristics of tenecteplase (e.g., similar half-life, rapid onset, and ease of administration). 

Drug Treatment. Because of the extensive nature of the pulmonary infarction, a thrombolytic agent was used to attempt to resolve the clot. An initial dosage of 250,000 units of streptokinase (Streptase) was administered intravenously within 2 hours after the onset of symptoms. Streptokinase was continued via intravenous infusion at a rate of 100,000 units/hr for 24 hours after the initial dose. 

Thrombolytic agents such as streptokinase, urokinase, and recombinant tissue-type plasminogen activator... 

In suitable patients a thrombolytic agent such as streptokinase may be given soon after a coronary occlusion to dissolve the thrombus and promote restoration of blood flow. 

Hemorrhage is the major risk of thrombolytic drugs there are some differences in risks between the various agents, and certain susceptibility factors can be identified. Transient hypotensive reactions have been described with all thrombolytic agents, but they are in principle reversible. Hypersensitivity reactions are most often seen in patients who have been treated with compounds derived from cultures of streptococci (streptokinase and anistreplase). Tumor-inducing effects have not been reported. 

The combination of thrombolytic agents with an anticoagulant and/or aspirin has been said to be life-threatening. An excess of major bleeding episodes with combined subcutaneous heparin and streptokinase or alteplase treatments (1.0% with heparin versus 0.5% without heparin) has been reported in the International Study Group Trial (103) in patients with suspected acute myocardial infarction. 

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