EP0442671B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Prolonged release microcapsules
Assignee: Takeda Pharmaceutical Co Ltd
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Filing: 1991-02-11
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Granted: 1995-06-07
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Expires: 2011-02-11
Abstract
Abstract This invention provides a microcapsule designed for zero order release of a physiologically active polypeptide over a period of at least two months, which is produced by preparing a water-in-oil emulsion comprising an inner aqueous layer containing about 20 to 70% (w/w) of said polypeptide and an oil layer containing a copolymer or homopolymer having a weight-average molecular weight of 7,000 to 30,000, the molar composition ratio of lactic acid/glycolic acid being 80/20 to 100/0, subjecting said water-in oil emulsion to microencapsulation.
Inventors
- 👤 Hiroaki Okada
- 👤 Yayoi Inoue
- 👤 Yasuaki 77-42 Koaza-Tanita Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 12:20
CPC Classifications
A; A61; A61K; A61K38/00; A61K38/04; A61K38/06; A61K38/066; A61K38/08; A61K38/09; A61K9/00; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
98 words
A microcapsule designed for zero order release of luteinizing hormone-releasing hormone (LH-RH) or an analog thereof over a period of at least two months, which is produced by preparing a water-in-oil emulsion comprising an inner aqueous phase containing 20 to 70% (w/w) of said LH-RH or analog, in the absence of a drug-retaining substance, and an oil phase containing a copolymer or homopolymer having a weight-average molecular weight of 7,000 to 30,000, the copolymer or homopolymer having a molar composition ratio of lactic acid/glycolic acid of 90/10 to 100/0, and then subjecting said water-in oil emulsion to microencapsulation.
Claim 2
Dependent Claim
29 words
The microcapsule according to claim 1, wherein said water-in-oil emulsion is dispersed in an aqueous phase and then the resulting water/oil/water ternary emulsion is subjected to an in-water drying.
Claim 3
Dependent Claim
21 words
The microcapsule according to claim 1, wherein the LH-RH analog is water-soluble and has a molecular weight of 1,000 or more.
Claim 4
Dependent Claim
13 words
The microcapsule according to claim 1, wherein said LH-RH analog is (pyr)Glu-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-ProNHC₂H₅ (TAP-144).
Claim 5
Dependent Claim
22 words
The microcapsule according to claim 1, wherein said homopolymer is a poly-lactic acid having a weight-average molecular weight of 7,000 to 25,000.
Claim 6
Dependent Claim
21 words
The microcapsule according to claim 1, wherein said inner aqueous phase contains 25 to 65% (w/w) of said LH-RH or analog.
Claim 7
Dependent Claim
21 words
The microcapsule according to claim 1, wherein said inner aqueous phase contains 35 to 60% (w/w) of said LH-RH or analog.
Claim 8
Dependent Claim
106 words
A process for preparing a microcapsule designed for zero order release of luteinizing hormone-releasing hormone (LH-RH) or an analog thereof over a period of at least two months, which comprises preparing a water-in-oil emulsion comprising an inner aqueous phase containing 20 to 70% (w/w) of the said LH-RH or analog in the absence of a drug-retaining substance, and an oil phase containing a copolymer or homopolymer having a weight average molecular weight of 7,000 to 30,000, the copolymer or homopolymer having a molar composition ratio of lactic acid/glycolic acid of 90/10 to 100/0, and then subjecting said water-in-oil emulsion to an in-water drying or phase-separation method.
Claim 9
Dependent Claim
29 words
The process according to claim 8, wherein said water-in-oil emulsion is dispersed in an aqueous phase and then the resulting water/oil/water ternary emulsion is subjected to an in-water drying.
Claim 10
Dependent Claim
24 words
The process according to claim 8, wherein the said water-in-oil emulsion is dispersed in an aqueous phase containing polyvinyl alcohol as an emulsifying agent.
Claim 11
Dependent Claim
21 words
The process according to claim 8, wherein said LH-RH analog is water-soluble and has a molecular weight of 1,000 or more.
Claim 12
Dependent Claim
13 words
The process according to claim 8, wherein said LH-RH analog is (pyr)Glu-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-ProNHC₂H₅ (TAP-144).
Claim 13
Dependent Claim
22 words
The process according to claim 8, wherein said homopolymer is a poly-lactic acid having a weight-average molecular weight of 7,000 to 25,000.
Claim 14
Dependent Claim
21 words
The process according to claim 8, wherein said inner aqueous phase contains 25 to 65% (w/w) of said LH-RH or analog.
Claim 15
Dependent Claim
21 words
The process according to claim 8, wherein said inner aqueous phase contains 35 to 60% (w/w) of said LH-RH or analog.
References Cited (Backward Citations)
No citation records indexed.
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