US4540566A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prolonged release drug dosage forms based on modified low viscosity grade hydroxypropylmethylcellulose
Assignee: Forest Laboratories LLC
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Filing: 1984-04-02
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Granted: 1985-09-10
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Expires: 2004-04-02
Abstract
Abstract A carrier base material combined with a therapeutically active medicament and shaped and compressed to a solid unit dosage form having a controlled and prolonged release pattern upon administration, the carrier base material being a mixture of one or more nonionic cellulose ethers and an anionic surfactant, and wherein at least one of the cellulose ethers is a modified hydroxypropylmethylcellulose having a number average molecular weight of less than 50,000 and has been modified by successive or concurrent exposure to moisture and air.
Inventors
- 👤 Stanley S. Davis
- 👤 Norman G. Gaylord
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:52
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2013; A61K9/2022; A61K9/205; A61K9/2054
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
84 words
A carrier base material combined with a therapeutically active medicament and shaped and compressed to a solid unit dosage form having a controlled and prolonged release pattern upon administration, the carrier base material being a mixture of one or more water-soluble nonionic cellulose ethers and an anionic surfactant, and wherein at least one of the cellulose ethers is a modified hydroxypropylmethylcellulose having a number average molecular weight of less than 50,000 and has been modified by successive or concurrent exposure to moisture and air.
Claim 2
Dependent Claim
84 words
A carrier base material combined with a therapeutically active medicament and shaped and compressed to a solid unit dosage form having a controlled and prolonged release pattern upon administration, the carrier base material being a mixture of one or more water-soluble nonionic cellulose ethers and an anionic surfactant, and wherein at least one of the cellulose ethers is a modified hydroxypropylmethylcellulose having a number average molecular weight of less than 50,000 and has been modified by successive or concurrent exposure to moisture and air.
Claim 3
Dependent Claim
23 words
A composition according to claim 1 wherein the hydroxypropylmethylcellulose has a methoxyl content of 28-30 weight-% and a hydroxypropoxyl content of 7.5-12 weight-%.
Claim 4
Dependent Claim
19 words
A composition according to claim 1 wherein the anionic surfactant is an alkali metal salt of an organic sulfate.
Claim 5
Dependent Claim
23 words
A composition according to claim 3 wherein the organic sulfate is selected from the group consisting of C 8 -C 24 alcohol sulfates.
Claim 6
Dependent Claim
17 words
A composition according to claim 3 wherein the organic sulfate is the sulfate of an ethoxylated compound.
Claim 7
Dependent Claim
19 words
A composition according to claim 1 wherein the anionic surfactant is an alkali metal salt of an organic sulfonate.
Claim 8
Dependent Claim
14 words
A composition according to claim 6 wherein the organic sulfonate is an aryl sulfonate.
Claim 9
Dependent Claim
14 words
A composition according to claim 6 wherein the organic sulfonate is a dialkyl sulfosuccinate.
Claim 10
Independent Claim
91 words
A method for the preparation of a therapeutically active solid unit dosage form having a controlled and prolonged release pattern upon administration, consisting of compressing and shaping a mixture of a therapeutically active medicament and a carrier base material consisting of a mixture of one or more water-soluble nonionic cellulose ethers and an anionic surfactant, and wherein at least one of the cellulose ethers is a modified hydroxypropylmethylcellulose having a number average molecular weight of less that 50,000 and has been modified by successive or concurrent exposure to moisture and air.
Claim 11
Independent Claim
91 words
A method for the preparation of a therapeutically active solid unit dosage form having a controlled and prolonged release pattern upon administration, consisting of compressing and shaping a mixture of a therapeutically active medicament and a carrier base material consisting of a mixture of one or more water-soluble nonionic cellulose ethers and an anionic surfactant, and wherein at least one of the cellulose ethers is a modified hydroxypropylmethylcellulose having a number average molecular weight of less that 50,000 and has been modified by successive or concurrent exposure to moisture and air.
References Cited (Backward Citations)
US3065143A
Cited
US3870790A
Cited
DE2732335A1
Cited
GB2021143A
Cited
US4344934A
Cited
EP0012523A1
Cited
US4264573A
Cited
US4226849A
Cited
US4259314A
Cited
GB2098867A
Cited
US4369172A
Cited
US4389393A
Cited
US4389393B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-09 | 1989-03-11 | 1989-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-09 | 1993-03-11 | 1993-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-09 | 1997-03-11 | 1997-09-10 | $7700.00 | Window Closed / Lapsed |