EP0103387A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Long-acting matrix tablet formulations
Assignee: Pfizer Inc
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Filing: 1983-08-03
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Granted: —
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Expires: 2003-08-03
Abstract
Abstract A pharmaceutical tablet which releases an initial burst of therapeutic agent and thereafter releases the agent at an essentially constant rate comprising an acid soluble therapeutic agent in an insoluble matrix, the tablet containing an acid insoluble, base soluble pharmaceutically acceptable component selected from polymers and fatty acids, a pharmaceutically acceptable organic acid and at least one pharmaceutically acceptable excipient, the component and the acid each being present in an amount of from about 1-25 percent by weight of the total composition.
Inventors
- 👤 Morgan Lee Beatty
- 👤 Wayne Alan Boettner
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 16:27
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2072; A61K9/2077; A61K9/2004
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
102 words
A process for preparing a pharmaceutical tablet comprising an acid soluble therapeutic agent in an insoluble matrix, which releases an initial burst of therapeutic agent and thereafter releases said agent at an essentially constant rate, said tablet containing an acid insoluble, base soluble pharmaceutically acceptable component selected from polymers and fatty acids, a pharmaceutically acceptable organic acid and at least one pharmaceutically acceptable excipient, said component and said acid each being present in an amount of from about 1-25 percent by weight of total composition which process comprises mixing the tablet ingredients together and compressing to give tablets of the desired size.
Claim 2
Dependent Claim
102 words
A process for preparing a pharmaceutical tablet comprising an acid soluble therapeutic agent in an insoluble matrix, which releases an initial burst of therapeutic agent and thereafter releases said agent at an essentially constant rate, said tablet containing an acid insoluble, base soluble pharmaceutically acceptable component selected from polymers and fatty acids, a pharmaceutically acceptable organic acid and at least one pharmaceutically acceptable excipient, said component and said acid each being present in an amount of from about 1-25 percent by weight of total composition which process comprises mixing the tablet ingredients together and compressing to give tablets of the desired size.
Claim 3
Dependent Claim
86 words
A process as claimed in claim 1 which comprises (a) blending, granulating and milling the therapeutic agent with one or more excipients, the acid insoluble, base soluble pharmaceutically acceptable component and optionally zein to give a first blend (b) blending granulating and milling the pharmaceutically acceptable organic acid with one or more excipients and optionally zein to give a second blend and (c) blending the first and second blend together, optionally with the addition of a lubricant, and compressing to give tablets of the desired size.
Claim 4
Dependent Claim
25 words
The process of claim 1 or claim 2 wherein said component is a polymeric acid phthlate and said acid is a mono- or polycarboxylic acid.
Claim 5
Dependent Claim
18 words
The process of claim 3 wherein said component is hydroxypropyl methylcellulose phthlate and said acid is citric acid.
Claim 6
Dependent Claim
46 words
The process of claim 1 or claim 2 wherein said component is present in an amount of from 3-15 percent by weight and said acid is present in an amount of from about 7-20 percent by weight both based on the weight of the total composition.
Claim 7
Dependent Claim
14 words
The process of claim 1 or claim 2 wherein said therapeutic agent is trimazosin.
Claim 8
Dependent Claim
14 words
The process of claim 1 or claim 2 wherein said therapeutic agent is theophylline.
Claim 9
Dependent Claim
22 words
The process of claim 1 or claim 2 wherein said excipient is selected from ethyl cellulose, hydrogenated vegetable oil and mixtures thereof.
Claim 10
Dependent Claim
37 words
The process of claim 1 or claim 2 wherein said tablet comprises about 40-60 weight percent trimazosin, about 4-5 weight percent ethyl cellulose, about 12-15 weight percent citric acid and about 3-7 weight percent hydroxypropyl methylcellulose phthlate.
Claim 11
Dependent Claim
16 words
The process of claim 9 wherein said tablet also contains from about 7-8 weight percent zein.
References Cited (Backward Citations)
No citation records indexed.
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