-
BMJ (Clinical Research Ed.) Feb 1991
Topics: Anistreplase; Humans; Myocardial Infarction; Recurrence; Streptokinase; Thrombolytic Therapy
PubMed: 2004167
DOI: 10.1136/bmj.302.6774.429 -
Bulletin of the World Health... 1965The National Institute for Medical Research, London, was asked by the WHO Expert Committee on Biological Standardization to take steps to set up an international...
The National Institute for Medical Research, London, was asked by the WHO Expert Committee on Biological Standardization to take steps to set up an international standard of streptokinase-streptodornase. This paper describes the nature and handling of the material and its establishment as the International Standard for Streptokinase-Streptodornase, with a defined potency of 3100 International Units of Streptokinase and 2400 International Units of Streptodornase per ampoule. The International Unit of Streptokinase is defined as the activity contained in 0.002090 mg of the International Standard for Streptokinase-Streptodornase. The International Unit of Streptodornase is defined as the activity contained in 0.002700 mg of the International Standard for Streptokinase-Streptodornase.
Topics: Biological Assay; In Vitro Techniques; International Cooperation; Streptodornase and Streptokinase; World Health Organization
PubMed: 5294594
DOI: No ID Found -
Journal of Thrombosis and Haemostasis :... Aug 2014Worldwide, streptokinase remains the most used thrombolytic agent for the treatment of myocardial infarction. Recombinant streptokinase, from E. coli, is increasingly...
BACKGROUND
Worldwide, streptokinase remains the most used thrombolytic agent for the treatment of myocardial infarction. Recombinant streptokinase, from E. coli, is increasingly used in developing countries as a biosimilar of native streptokinase; however, potency assignments relative to the WHO International Standard (IS) are highly variable with potentially dangerous consequences. A proportion of recombinant streptokinase appears to be incompletely processed, retaining the amino-terminal methionine engineered for intracellular expression.
OBJECTIVES
To investigate and quantify the impact of an amino-terminal methionine on streptokinase activity.
METHODS
Mature native streptokinase (rSK) was cloned and a novel variant constructed to include an amino-terminal methionine (rSK-Met) that is not susceptible to processing during expression. Potencies of rSK and rSK-Met were determined relative to the WHO IS using a chromogenic solution (European Pharmacopoeia) assay, and fibrin-based assays.
RESULTS
In the chromogenic solution assay there was no measurable difference between rSK and rSK-Met activities. In the fibrin-based methods, however, potency estimates for rSK-Met were greatly reduced compared with rSK, and fibrinolytic activity for rSK-Met was shown to increase over time with methionine aminopeptidase treatment. This apparent difference in activity and fibrin selectivity was consistent with potency estimates for several different batches of commercial recombinant streptokinase products also tested; consequently, different potencies would be assigned to therapeutic recombinant streptokinase products depending on the degree of amino-terminal methionine processing, and on the pharmacopoeial assay method used, affecting the dosage patients receive. This has serious health implications and provides an example of the danger in the unregulated clinical use of biosimilars.
Topics: Biosimilar Pharmaceuticals; Cloning, Molecular; Humans; Recombinant Proteins; Streptokinase; Thrombolytic Therapy
PubMed: 24913658
DOI: 10.1111/jth.12629 -
Blood Jul 1990The catabolism of streptokinase (SK) and polyethylene glycol derivatives of SK (PEG-SK) were studied in mice. The clearance and catabolism of SK:plasmin (SK:Pm) and...
The catabolism of streptokinase (SK) and polyethylene glycol derivatives of SK (PEG-SK) were studied in mice. The clearance and catabolism of SK:plasmin (SK:Pm) and PEG-SK:Pm activator complexes were also investigated. Native 125I-SK cleared rapidly (t1/2 = 15 minutes) from the circulation, with the majority of the ligand accumulating in the liver and gastrointestinal (GI) tract and a substantial fraction also localizing in the kidneys. SK, which was removed from the plasma by the liver, was secreted into bile and then the GI tract. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that 125I-SK recovered from liver and bile was homogeneous and of the same molecular weight (mol wt approximately 50,200) as native SK. PEG-125I-SK cleared slowly (t1/2 greater than 200 minutes), with more than 80% of the preparation localizing in liver and GI tract. The PEG-125I-SK secreted into the bile was also intact. The bile containing 125I-SK was incubated with stoichiometric amounts of plasminogen and electrophoresed under nondenaturing conditions. This study demonstrated that the secreted SK was able to form SK:Pg complexes. SDS-PAGE also showed activation of 125I-Pg that was incubated with recovered bile containing the SK. 125I-SK:Pm catabolism was also studied. In these experiments, the mol wt approximately 42,000 fragment obtained when SK is cleaved by plasmin was found in the bile. This fragment of 125I-SK was not recovered as part of a complex with plasmin, consistent with our previous observations that catabolism of SK:Pm involves transfer of the plasmin to plasma proteinase inhibitors while SK is catabolized independently. By contrast, when PEG-125I-SK:Pm was injected into mice, only intact PEG-125I-SK was found in the bile, consistent with our previous observations that the PEG derivatization blocks its degradation by plasmin.
Topics: Animals; Biliary Tract; Biological Transport; Fibrinolysin; Iodine Radioisotopes; Mice; Plasminogen; Polyethylene Glycols; Streptokinase; Tissue Distribution
PubMed: 2142009
DOI: No ID Found -
Thorax Sep 1994Significant morbidity and mortality result from the ineffective evacuation of empyema. Failure of conventional first line treatment with closed intercostal tube drainage...
BACKGROUND
Significant morbidity and mortality result from the ineffective evacuation of empyema. Failure of conventional first line treatment with closed intercostal tube drainage and antibiotic therapy may result in fibrin deposition and loculated empyema. Enzymatic debridement using intrapleural instillation of streptokinase is a non-invasive therapeutic option which may obviate the need for surgical intervention.
METHODS
Eleven adults with multiloculated post-pneumonic empyemas who had failed to respond satisfactorily to intercostal tube drainage and antibiotic therapy were treated with intrapleural streptokinase between November 1992 and January 1994. A small catheter was inserted under ultrasound guidance into a loculation within the pleural space. Aliquots of 250,000 units of streptokinase in 100 ml normal saline were instilled into the pleural cavity and the tube clamped for four hours. Response was assessed by clinical outcome, measurement of drain output after unclamping, and subsequent pleural ultrasound, chest radiography, or both.
RESULTS
Streptokinase enhanced drainage in all patients. Complete resolution of the empyema with re-expansion of the underlying lung was effected in eight patients, all of whom remain well. Further resolution of minimal pleural thickening was shown on subsequent chest radiographs. Two patients with considerably thickened visceral pleura following empyema drainage underwent successful decortication. The other, with myocarditis and a pyopneumothorax, underwent surgery for non-resolution of the pneumothorax but died perioperatively from cardiac failure. The number of streptokinase instillations per patient ranged from two to six (median three), and the volume of empyema fluid drained per patient ranged from 100 ml to 4870 ml (median 900 ml). Streptokinase was well tolerated in all patients.
CONCLUSIONS
Intrapleural streptokinase is an effective adjunct in the management of complicated empyema and may reduce the need for surgery.
Topics: Adult; Aged; Drainage; Drug Administration Schedule; Empyema, Pleural; Female; Humans; Instillation, Drug; Lung; Male; Middle Aged; Radiography; Streptokinase
PubMed: 7940421
DOI: 10.1136/thx.49.9.856 -
California Medicine Nov 1963Thrombolytic therapy holds great promise for becoming an important therapeutic adjunct in the treatment of acute vascular occlusions, but such therapy has not reached... (Review)
Review
Thrombolytic therapy holds great promise for becoming an important therapeutic adjunct in the treatment of acute vascular occlusions, but such therapy has not reached the stage for general clinical use. The optimum method of administering thrombolytic agents has not yet been determined, and the processes that bring about lysis of clots are incompletely understood. Current theories in this field are reviewed and the suggested modes of therapy and potential complications are discussed.
Topics: Anticoagulants; Aspergillus; Blood Coagulation; Blood Coagulation Factors; Deoxyribonuclease I; Fibrinolysin; Fibrinolysis; Pyrogens; Streptodornase and Streptokinase; Streptokinase; Thrombolytic Therapy; Thrombosis; Vascular Diseases
PubMed: 14081772
DOI: No ID Found -
Applied and Environmental Microbiology Mar 1998The short in vivo half-life of streptokinase limits its efficacy as an efficient blood clot-dissolving agent. During the clot-dissolving process, streptokinase is...
The short in vivo half-life of streptokinase limits its efficacy as an efficient blood clot-dissolving agent. During the clot-dissolving process, streptokinase is processed to smaller intermediates by plasmin. Two of the major processing sites are Lys59 and Lys386. We engineered two versions of streptokinase with either one of the lysine residues changed to glutamine and a third version with both mutations. These mutant streptokinase proteins (muteins) were produced by secretion with the protease-deficient Bacillus subtilis WB600 as the host. The purified muteins retained comparable kinetics parameters in plasminogen activation and showed different degrees of resistance to plasmin depending on the nature of the mutation. Muteins with double mutations had half-lives that were extended 21-fold when assayed in a 1:1 molar ratio with plasminogen in vitro and showed better plasminogen activation activity with time in the radial caseinolysis assay. This study indicates that plasmin-mediated processing leads to the inactivation of streptokinase and is not required to convert streptokinase to its active form. Plasmin-resistant forms of streptokinase can be engineered without affecting their activity, and blockage of the N-terminal cleavage site is essential to generate engineered streptokinase with a longer in vitro functional half-life.
Topics: Bacillus subtilis; Fibrinolysin; Half-Life; Mutagenesis, Site-Directed; Plasminogen; Protein Engineering; Streptokinase
PubMed: 9501422
DOI: 10.1128/AEM.64.3.824-829.1998 -
Thorax Sep 1994Intrapleural administration of streptokinase has been shown in a few small series to be effective treatment for complicated parapneumonic effusions and pleural empyemas,...
BACKGROUND
Intrapleural administration of streptokinase has been shown in a few small series to be effective treatment for complicated parapneumonic effusions and pleural empyemas, but techniques of instillation of streptokinase differ. The role of streptokinase in promoting drainage was investigated prospectively in a larger series of patients with complicated parapneumonic effusions and pleural empyemas.
METHODS
Twenty consecutive patients with parapneumonic effusions, 15 with complicated parapneumonic effusions and five with pleural empyemas, drawn from 160 patients presenting with pleural effusions were studied. The age of the patients ranged from 15 to 92 years. Initial thoracocentesis showed mean (SD) values of pH 7.1 (0.15), glucose 45.9 (17.5) mg/dl, white blood cell count 12,000 (6627)/mm3. Streptokinase was administered intrapleurally in a single daily dose of 250,000 units in 100 ml normal saline via the chest tube once the drainage was < 100 ml/24 hours. Patients were treated for 3-10 (mean 6) days.
RESULTS
Following administration of streptokinase a clinical and radiological improvement was noted in all but one patient who died on the fourth day of hospitalisation due to widespread adenocarcinoma. Another patient with clinical but minimal radiological improvement underwent thoracotomy, but a clear pleural space with only fibrotic changes was found. The mean (SD) volume of fluid drained 24 hours before streptokinase was 42.5 (39) ml, which increased in the first 24 hours after streptokinase to 334 (130) ml. Radiological evaluation showed an excellent improvement in 14 of the 20 patients, a moderate improvement in three, and minimal improvement in the remaining three patients. One patient developed a high fever as an adverse reaction to streptokinase. All 19 patients who completed the treatment were well at follow up 6-30 months (mean 15 months) later.
CONCLUSIONS
Intrapleural instillation of streptokinase is an effective and safe mode of treatment for complicated parapneumonic effusions and pleural empyemas and alleviates the need for thoracotomy.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Drainage; Empyema, Pleural; Female; Humans; Instillation, Drug; Male; Middle Aged; Pleural Effusion; Prospective Studies; Streptokinase
PubMed: 7940420
DOI: 10.1136/thx.49.9.852 -
British Heart Journal Nov 1992(a) To develop an assay for streptokinase resistance. (b) To determine the prevalence of streptokinase resistance in patients presenting with acute myocardial infarction...
OBJECTIVE
(a) To develop an assay for streptokinase resistance. (b) To determine the prevalence of streptokinase resistance in patients presenting with acute myocardial infarction for the first time. (c) To determine the prevalence of streptokinase resistance in patients after exposure to streptokinase or streptococcal infection.
DESIGN
Open, prospective.
PATIENTS
30 healthy volunteers. 40 patients admitted to the coronary care unit at Addenbrooke's Hospital with suspected acute myocardial infarction, 12 patients 12 months after streptokinase treatment, eight patients 24 months after streptokinase treatment, and sera from 12 patients with raised anti-streptolysin O (ASO) titres.
METHODS
Three assays were used; a dilution neutralisation assay, an enzyme linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) anti-streptokinase antibodies, and an in vitro fibrin plate lysis assay. All measurements were performed on venous blood samples.
RESULTS
Neutralisation and IgG antibody titres were positively correlated. Mean (SEM) antistreptokinase concentrations in the 30 controls were 87 (10) U/ml (neutralisation assay) and 28 (6.3) U/ml (ELISA). Corresponding concentrations in patients before streptokinase were 68 (6.1) U/ml and 18 (4.5) U/ml with a mean fibrin plate assay 117 (7.1)% that of controls. Resistance to streptokinase was detectable in one patient after 72 hours and in all patients by day 10. By day 10 concentrations were 4388 (919) U/ml, 773 (109) U/ml, and 17 (5.4)%. At both 12 and 24 months resistance was present in 75% of patients. Similarly 66% of high ASO titre sera showed resistance. The fibrin plate lysis assay detected significantly reduced streptokinase dependent fibrinolysis in vitro in the absence of raised total concentrations of antistreptokinase antibodies.
CONCLUSIONS
The prevalence of streptokinase resistance in patients presenting with their first myocardial infarction is low. Resistance develops early after treatment and is still present in 75% of patients after 24 months. Retreatment with streptokinase is likely to be suboptimal even after 24 months. The fibrin plate lysis assay detects resistance in patients with normal concentrations of streptokinase antibodies. Streptococcal infection is associated with a high incidence of streptokinase resistance.
Topics: Antibodies; Drug Resistance; Enzyme-Linked Immunosorbent Assay; Fibrinolysis; Humans; Immunoglobulin G; Myocardial Infarction; Neutralization Tests; Prevalence; Prospective Studies; Streptococcal Infections; Streptokinase; Thrombolytic Therapy; Time Factors
PubMed: 1467027
DOI: 10.1136/hrt.68.11.449 -
British Heart Journal Aug 1992To examine the induction of antistreptokinase antibodies after giving streptokinase or anistreplase to patients with acute myocardial infarction. (Clinical Trial)
Clinical Trial Randomized Controlled Trial
Monitoring of streptokinase resistance titre in acute myocardial infarction patients up to 30 months after giving streptokinase or anistreplase and related studies to measure specific antistreptokinase IgG.
OBJECTIVE
To examine the induction of antistreptokinase antibodies after giving streptokinase or anistreplase to patients with acute myocardial infarction.
DESIGN
Patients were randomly allocated to receive either 1.5 x 10(6) IU, streptokinase or 30U anistreplase in a double blind study. Blood samples were collected immediately before treatment and subsequently at intervals up to 30 months; plasma samples were assayed for streptokinase resistance titre (functional assay) and streptokinase binding by IgG (microradioimmunoassay).
SETTING
Cardiology department in a general hospital.
PATIENTS
128 consecutive eligible patients. Samples were collected for up to one year according to a prospective design: a subsection of 47 patients was selected for intensive study over the first 14 days. After one year, all available patients (67) were sampled on one further occasion.
RESULTS
Antibody responses to streptokinase and anistreplase were similar. Streptokinase resistance titres exceeded pretreatment concentrations five days after dosing, and values peaked at 14 days. By 12 months after dosing, 92% of resistance titres (n = 84) had returned to within the pretreatment range. Antistreptokinase IgG concentrations also exceeded baseline concentrations within five days and peaked at 14 days. Half of the individual values had returned to within the pretreatment range by 12 months (n = 84) and 89% by 30 months (n = 18).
CONCLUSION
Although we cannot be sure of the clinical significance, because of the increased likelihood of resistance due to antistreptokinase antibody, streptokinase and anistreplase may not be effective if administered more than five days after an earlier dose of streptokinase or anistreplase, particularly between five days and 12 months, and increased antistreptokinase antibody may increase the risk of allergic-type reactions.
Topics: Adult; Aged; Anistreplase; Antibodies; Antibody Formation; Double-Blind Method; Drug Resistance; Female; Humans; Immunoglobulin G; Male; Middle Aged; Myocardial Infarction; Prospective Studies; Streptokinase; Thrombolytic Therapy; Time Factors
PubMed: 1389731
DOI: 10.1136/hrt.68.8.167