Patent EP0112122A2 successfully refreshed from Google Patents.
EP0112122A2
Expired / Lapsed
EP
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Plasminogen activator
Assignee: South African Inventions Development Corp
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Filing: 1983-12-08
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Granted: —
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Expires: 2003-12-08
Abstract
Abstract The invention provides a process for producing a purified plasminogen activator substance based on the TPA/pro-TPA couple. Pro-TPA yielding cell cultures are cultivated in a suitable culture medium in the absence of enzymes which catalyse the conversion of pro-TPA into TPA or where such enzymes are present in the presence of a suitable inhibitor adapted to inhibit such enzymes. Accord- : ingly the couple is represented in the harvesting liquid by at least 50 to 100% of pro-TPA and can in fact be virtually 100% pro-TPA, any balance being TPA. The harvesting fluid is treated with an affinity reagent comprising an immobilised Kunitz type inhibitor of the type occurring in seeds of Erythrina latissima and other Erythrina species (DE-3) to selectively adsorb the pro-TPA and any TPA in the harvesting fluid, followed by desorption of pro-TPA and optionally TPA. The pro-TPA so recoverable has 1/10 the plasminogen activating properties of TPA. It is convertable into active TPA enzymatically, e.g. by plasmin or by enzymes present in fibrin clots. The pro-TPA has a higher affinity for fibrin and better selectivity than TPA. It is used for the management and prophylaxis of thrombosis and embolism in dosages of pro-TPA/TPA couple which result in less than 50%, e.g. less than 20% of the plasminogen activating activity resulting from up to 15 mg/24 hrs pure TPA.
Inventors
- 👤 Eugene Bernard Davey Dowdle
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 17:21
CPC Classifications
C; C12; C12N; C12N9/00; C12N9/14; C12N9/48; C12N9/50; C12N9/64; C12N9/6421; C12N9/6424; C12N9/6456; C12N9/6459; C12Y; C12Y304/00; C12Y304/21; C12Y304/21069; A; A61; A61K; A61K38/00; Y; Y10; Y10S; Y10S435/00; Y10S435/814; Y10S435/815
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
189 words
A method of producing a purified plasminogen activator substance based on the TPA/pro-TPA couple. which comprises cultivating a pro-TPA yielding cell culture in a suitable culture medium,characterised by the combination that the cells are cultivated in the absence of enzymes which catalyse the conversion of pro-TPA into TPA or, where such enzymes are present,. in the presence of a suitable inhibitor adapted to inhibit such enzymes, to produce a harvesting liquid wherein the couple is represented by 50 - 100% nor-TPA, the balance beina TPA. and that the harvesting fluid. containing the dissolved pro-TPA and contaminants is intimately contacted with an affinity reagent comprising an immobilised Kunitz type inhibitor of the type: occurring in seeds of Erythrina latissima and other Erythrina species and having the property of being an inhibitor for trypsin, plasmin and TPA but having no effect on urokinase, thereby selectively adsorbing the pro-TPA and any TPA from the medium, removing the affinity reagent loaded with pro-TPA (and TPA) from contact with the aqueous medium and non-adsorbed contaminants; desorbing the pro-TPA and any TPA from the affinity reagent and recovering the desorbed pro-TPA and optionalny the TPA:
Claim 2
Independent Claim
189 words
A method of producing a purified plasminogen activator substance based on the TPA/pro-TPA couple. which comprises cultivating a pro-TPA yielding cell culture in a suitable culture medium,characterised by the combination that the cells are cultivated in the absence of enzymes which catalyse the conversion of pro-TPA into TPA or, where such enzymes are present,. in the presence of a suitable inhibitor adapted to inhibit such enzymes, to produce a harvesting liquid wherein the couple is represented by 50 - 100% nor-TPA, the balance beina TPA. and that the harvesting fluid. containing the dissolved pro-TPA and contaminants is intimately contacted with an affinity reagent comprising an immobilised Kunitz type inhibitor of the type: occurring in seeds of Erythrina latissima and other Erythrina species and having the property of being an inhibitor for trypsin, plasmin and TPA but having no effect on urokinase, thereby selectively adsorbing the pro-TPA and any TPA from the medium, removing the affinity reagent loaded with pro-TPA (and TPA) from contact with the aqueous medium and non-adsorbed contaminants; desorbing the pro-TPA and any TPA from the affinity reagent and recovering the desorbed pro-TPA and optionalny the TPA:
Claim 3
Dependent Claim
28 words
Process according to claim 1, characterised in that the pro-TPA and/any TPA is contaminated with urokinase and the urokinase is removed with the non-adsorbed contaminants and optionally recovered.
Claim 4
Dependent Claim
21 words
Process according to claim 1 or Z characterised in that the aqueous medium is derived from cultivating a melanoma cell culture.
Claim 5
Dependent Claim
55 words
Process accarding to any one of claims 1 to 3, characterised in that the pro-TPA and/any TPA is adsorbed-by passing the aqueous medium containing it through a bed of the affinity reagent, followed by washing the bed and subsequent desorption of the pro-TPA and/any TPA and washing the desorbed TPA and/or pro-TPA off the bed.
Claim 6
Dependent Claim
53 words
A pharmaceuticaT composition for the management of prophylaxis of thrombosis or other conditions where it is desired to produce Tocal fibrinolytic or proteolytic activity via the mechanism of plasminogen activation which comprises pro-TPA prepared and purified by a process according to any one of claims 1 to 4, dissolved in an injection medium.
Claim 7
Dependent Claim
33 words
A composition which induces fibrinolysis in fibrin and which comprises wholly or predominantly pro-TPA as the active ingredient prepared and purified by a process according to any one of claims 1 to 4.
Claim 8
Dependent Claim
104 words
A pharmaceutical composition for the management or prophylaxis of thrombosis, embolism or other condition where it is desired to produce local fibrinolytic or proteolytic activity via the mechanism of plasminogen activation which comprises a plasminogen-activator component presented by the TPA/pro-TPA couple,. composed of 50 to 100. %. pro-TPA: and 0 ta 50%. TPA, the composition being i ng: adapted for intravenous administration in dosage units for injection or for intravenous infusion , and designed to produce in the bloodstream an average plasminogen activator activity of less than half that which results from the administration of up- to 15 mg per 24 hours of TPA.
Claim 9
Dependent Claim
104 words
A pharmaceutical composition for the management or prophylaxis of thrombosis, embolism or other condition where it is desired to produce local fibrinolytic or proteolytic activity via the mechanism of plasminogen activation which comprises a plasminogen-activator component presented by the TPA/pro-TPA couple,. composed of 50 to 100. %. pro-TPA: and 0 ta 50%. TPA, the composition being i ng: adapted for intravenous administration in dosage units for injection or for intravenous infusion , and designed to produce in the bloodstream an average plasminogen activator activity of less than half that which results from the administration of up- to 15 mg per 24 hours of TPA.
Claim 10
Dependent Claim
21 words
A composition according to claim 7 in dosage units for intermittent intravenous injection of up to 15 mg of TPA/PRO-TPA couple.
Claim 11
Dependent Claim
23 words
in 9. A composition according to claim 8 dosage units of 3 - 15 mg of TPA/pro-TPA couple, for a 24 hour treatment.
Claim 12
Dependent Claim
26 words
A composition according to claim 7 adapted for intravenous infusion and formulated for a dosage rate of 3 - 15 mg/24 hours (1/8 - 5/8 mg/hr).
Claim 13
Dependent Claim
29 words
A composition according to any one of claims. 7 to 10, characterised in that the TPA/pro-TPA couple is represented by 70 ta 100% pro-TPA and 0 - 30% TPA.
Claim 14
Dependent Claim
31 words
A composition according to any one of claims 7 to 11 characterised in that the TPA/pro-TPA couple is represented by 80 - 100 % pro-TPA and 0 - 20 % TPA.
Claim 15
Dependent Claim
23 words
A composition according to any one o.f claims 7 to 12 characterised in that the TPA/pro-TPA couple is represented by essentially pure pro-TPA.
Claim 16
Dependent Claim
56 words
A composition accarding to claim 7 for the prophylaxis of conditions likely to result in thrombosis or embolism in dosage units for intravenous administrations of 1 to 10 mg of TPA/ pro-TPA couple or in the form of an infusion solution adapted for an infusion rate of 0,5 to Z mg per hour of TPA/pro-TPA couple.
Claim 17
Dependent Claim
108 words
A composition according to claim 7, characterised in that the TPA/pro-TPA couple has been purified by a process which comprises intimately contacting an aqueous medium containing dissolved pro-TPA and optionally TPA with an affinity reagent comprising an immobilised Kunitz type inhibitor of the type occurring in seeds of Erythrina latissima and other Erythrina species and having the property of being an inhibitor for trypsin, plasmin and TPA, but having no effect on urokinase, thereby selectively adsorbing the pro-TPA and/any TPA from the solution, removing the affinity reagent loaded with pro-TPA and/any TPA from contact with the aqueous medium.depleted of pro-TPA and/any TPA, and recovering the pro-TPA and/optionally TPA.
Claim 18
Dependent Claim
48 words
A composition according to any one of the preceding claims, characterised in that it is adapted to produce on injection into the bloodstream an average plaminogen activator activity of 5 to 30% that which results from the administration of up to 15 mg per 24 hours of TPA.
Claim 19
Dependent Claim
49 words
T7.. A compositon according to any one of the preceding claims, characterised in that it is adapted to produce on injection into the bloodstream an average plasminogen activator activity of less than 20% that which results from the administration of up to 15 mg per 24 hours of TPA.
Claim 20
Dependent Claim
33 words
The use of the TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA as a local fibrinolytic agent in the treatment or prophylaxis of thrombosis, embolism and the like.
Claim 21
Dependent Claim
33 words
The use of the TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA as a local fibrinolytic agent in the treatment or prophylaxis of thrombosis, embolism and the like.
Claim 22
Dependent Claim
30 words
The TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA, far use as a local fibrinolytic agent in the treatment of trombosis, embolism and the like.
Claim 23
Dependent Claim
30 words
The TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA, far use as a local fibrinolytic agent in the treatment of trombosis, embolism and the like.
Claim 24
Dependent Claim
40 words
The use of the TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA in the preparation of a pharmaceutical formulation, as a local fibrinolytic agent in the treatment or prophyloxis of thrombosis, embolism and the like.
Claim 25
Dependent Claim
40 words
The use of the TPA/pro-TPA couple composed of 50 to 100% pro-TPA and 0 to 50% TPA in the preparation of a pharmaceutical formulation, as a local fibrinolytic agent in the treatment or prophyloxis of thrombosis, embolism and the like.
References Cited (Backward Citations)
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