Patent EP0253541A2 successfully refreshed from Google Patents.
EP0253541A2
Expired / Lapsed
EP
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Sustained release pharmaceutical compositions in oral dosage form
Assignee: Organon Pharma UK Ltd
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Filing: 1987-07-02
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Granted: —
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Expires: 2007-07-02
Abstract
Abstract Oral dosage forms for neutral, zwitterions or salts of acidic or basic drugs with approximate zero order release kinetics comprise a core matrix of the drug, and a gelling polymer, the matrix being coated with a water permeable but insoluble polymer.
Inventors
- 👤 Claire Jacqueline Lovegrove
- 👤 Anthony John Phillips
- 👤 David Alexander Rawlins
- 👤 David Alexander Tainsh
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 23:38
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/20; A61K9/28; A61K9/2806; A61K9/2833; A61K9/286; A61K9/2866; A61K9/2004; A61K9/2013; A61K9/2022; A61K9/205; A61K9/2054; A61P; A61P25/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
61 words
A method of preparing a sustained release pharmaceutical composition in oral dosage form containing an active ingredient which comprises forming a matrix containing at least 20% of a derivatized cellulosic gelling agent having said active ingredient homogeneously dispersed therein optionally together with pharmaceutically acceptable excipients, and forming a coating on said matrix comprising a slowly soluble water permeable derivatized cellulosic polymer.
Claim 2
Independent Claim
61 words
A method of preparing a sustained release pharmaceutical composition in oral dosage form containing an active ingredient which comprises forming a matrix containing at least 20% of a derivatized cellulosic gelling agent having said active ingredient homogeneously dispersed therein optionally together with pharmaceutically acceptable excipients, and forming a coating on said matrix comprising a slowly soluble water permeable derivatized cellulosic polymer.
Claim 3
Dependent Claim
13 words
The method of Claim 1 wherein the core matrix contains a buffering agent.
Claim 4
Dependent Claim
12 words
The method of Claim 2 wherein the buffering agent is citric acid.
Claim 5
Independent Claim
18 words
The method of any one of Claims 1 to 3 wherein the core matrix gelling agent is hydroxypropylmethylcellulose.
Claim 6
Dependent Claim
15 words
The method of Claim 4 wherein the hydroxypropylmethylcellulose has a viscosity of about 4,000 centipoises.
Claim 7
Independent Claim
28 words
The method of any one of Claims 1 to 5 wherein the derivatized cellulosic polymer in the coating layer is a water permeable, water insoluble film forming agent.
Claim 8
Dependent Claim
13 words
The method of Claim 6 wherein the film forming agent is ethyl cellulose.
Claim 9
Independent Claim
18 words
The method of any one of Claims 1 - 7 wherein the medicament is (+)-trans-1a,2,3,4a,5,6-hexahydro-9-hydroxy-4-(1-propyl)-4H-naphth[1,2b -1, 4-oxazine hydrochloride.
References Cited (Backward Citations)
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