EP0294103A1
Expired / Lapsed
EP
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A sustained-release preparation and production thereof
Assignee: Takeda Pharmaceutical Co Ltd
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Filing: 1988-05-26
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Granted: —
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Expires: 2008-05-26
Abstract
Abstract The present invention concerns a sustained-release microcapsule preparation comprising an ion exchange resin with 6 to 16% crosslinking, containing a drug adsorbed to not less than 80% of its theoretical ion adsorption amount and coated with a water-permeable polymer. The sustained-release preparation of this invention contains a high concentration of an absorbed drug: it shows neither cracking nor breaking in its coat and exhibits good sustained-release properties which enhance its dosage form design and makes it easy to take.
Inventors
- 👤 Muneo Nonomura
- 👤 Yasuyuki Suzuki
- 👤 Masayuki Yamada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 14:10
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5036; A61K9/5042; A61K9/5047; A61K47/00; A61K47/50; A61K47/51; A61K47/56; A61K47/58; A61K47/585; A61K9/5026
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
35 words
A sustained-release microcapsule preparation comprising an ion exchange resin of 6 to 16% crosslinking, containing a drug adsorbed to not less than 80% of its theoretical ion adsorption amount, and coated with a water-permeable polymer.
Claim 2
Dependent Claim
35 words
A sustained-release microcapsule preparation comprising an ion exchange resin of 6 to 16% crosslinking, containing a drug adsorbed to not less than 80% of its theoretical ion adsorption amount, and coated with a water-permeable polymer.
Claim 3
Dependent Claim
17 words
The preparation according to claim 1, wherein the ion exchange resin is a synthetic insoluble porous polymer.
Claim 4
Dependent Claim
16 words
The preparation according to claim 2, wherein the polymer is a copolymer of styrene and divinylbenzene.
Claim 5
Dependent Claim
17 words
The preparation according to claim 1, wherein the ion exchange resin is an acidic ion exchange resin.
Claim 6
Dependent Claim
25 words
The preparation according to claim 1, wherein the drug has a pKa from 6 to 10 or from 2 to 5 with a stericallybulky structure.
Claim 7
Dependent Claim
13 words
The preparation according to claim 1, wherein the drug is for respiratory tract.
Claim 8
Dependent Claim
19 words
The preparation according to claim 1, wherein the drug is a free form derived from the corresponding salt form.
Claim 9
Dependent Claim
14 words
The preparation according to claim 6, wherein the drug is dihydrocodein, phenylpropanolamine or dl-methylephedrin.
Claim 10
Dependent Claim
17 words
The preparation according to claim 1, wherein the ion exchange resin complex is coated with non-natural polymer.
Claim 11
Dependent Claim
20 words
The preparation according to claim 1, wherein the mean particle size of the microcapsule is from 5 to 1,000 µm.
Claim 12
Dependent Claim
18 words
A suspension for oral administration containing the preparation according to claim 1 in suspension in a purified water.
Claim 13
Dependent Claim
42 words
A method of producing the preparation according to claim 1, which comprises coating an ion exchange resin of 6 to 16% crosslinking and containing a drug adsorbed to not less than 80% of its theoretical ion adsorption amount with a water-permeable polymer.
Claim 14
Dependent Claim
66 words
The method according to claim 12, wherein the drug-ion exchange resin complex is produced by adding an ion exchange resin of 6 to 16% crosslinking to an aqueous solution of a drug in a free form prepared by reacting a salt of the drug with an ion exchange resin in an aqueous solvent capable of dissolving both the salt and the free form of the drug.
References Cited (Backward Citations)
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