US4623588A
Expired / Lapsed
US
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Controlled release composite core coated microparticles
Assignee: Biotek Inc
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Filing: 1985-12-02
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Granted: 1986-11-18
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Expires: 2005-12-02
Abstract
Abstract A process for preparing coated microparticles, which process comprises preparing a solvent solution of an active ingredient to be encapsulated and a film-forming polymer, removing the solvent to provide a dry, composite, uniform admixture of the active ingredient and the polymer material, reducing the composite admixture to a defined smaller particle size distribution, coating the reduced composite core particles in a fluidized bed, with a uniform defined wall thickness of the same or substantially the same film-forming polymer material to provide composite core coated microparticles.
Inventors
- 👤 Elie S. Nuwayser
- 👤 William A. Nucefora
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:02
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5031; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2989
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
129 words
A microparticle suitable for the controlled release of an active ingredient, which microparticle comprises: (a) a solid composite core material comprising a uniform dispersion of a finely-divided active ingredient and a film-forming polymer, the active ingredient present in an amount of from about 5% to 95% by weight of the core material; (b) a generally uniform outer wall coating about the composite core material in a wall thickness, to provide for the desired controlled release of the active ingredient, said outer wall coating comprising a film-forming polymer the same or substantially the same as the said film-forming polymer in the core material, to provide for bonding of the wall coating of the film-forming polymer to the core material; and (c) the microparticle less than about 1000 microns in size.
Claim 2
Dependent Claim
129 words
A microparticle suitable for the controlled release of an active ingredient, which microparticle comprises: (a) a solid composite core material comprising a uniform dispersion of a finely-divided active ingredient and a film-forming polymer, the active ingredient present in an amount of from about 5% to 95% by weight of the core material; (b) a generally uniform outer wall coating about the composite core material in a wall thickness, to provide for the desired controlled release of the active ingredient, said outer wall coating comprising a film-forming polymer the same or substantially the same as the said film-forming polymer in the core material, to provide for bonding of the wall coating of the film-forming polymer to the core material; and (c) the microparticle less than about 1000 microns in size.
Claim 3
Dependent Claim
161 words
A microparticle suitable for the controlled release of an active ingredient, which microparticle comprises: (a) a solid composite core material comprising a uniform dispersion of a finely-divided active drug ingredient, which drug ingredient comprises a hydrophobic steroid drug, and a film-forming polymer which comprises a biodegradable polymer selected from the group consisting of a polylactide, a polyglycolide, or a copolymer of lactide or glycolide, the active drug ingredient present in an amount of from about 5% to 95% by weight of the core material; (b) a generally uniform outer wall coating about the composite core material in a wall thickness, to provide for the desired controlled release of the active ingredient, said outer wall coating comprising a film-forming polymer the same or substantially the same as the said film-forming polymer in the core material, to provide for bonding of the wall coating of the film-forming polymer to the core material; and (c) the microparticle less than about 200 microns in size.
Claim 4
Dependent Claim
161 words
A microparticle suitable for the controlled release of an active ingredient, which microparticle comprises: (a) a solid composite core material comprising a uniform dispersion of a finely-divided active drug ingredient, which drug ingredient comprises a hydrophobic steroid drug, and a film-forming polymer which comprises a biodegradable polymer selected from the group consisting of a polylactide, a polyglycolide, or a copolymer of lactide or glycolide, the active drug ingredient present in an amount of from about 5% to 95% by weight of the core material; (b) a generally uniform outer wall coating about the composite core material in a wall thickness, to provide for the desired controlled release of the active ingredient, said outer wall coating comprising a film-forming polymer the same or substantially the same as the said film-forming polymer in the core material, to provide for bonding of the wall coating of the film-forming polymer to the core material; and (c) the microparticle less than about 200 microns in size.
Claim 5
Dependent Claim
14 words
The microparticle of claim 1 which is less than about 200 microns in size.
Claim 6
Dependent Claim
24 words
The microparticles of claim 1 wherein the film-forming polymer is selected from the group consisting of a biodegradable polymer, polyvinyl alcohol, and cellulose material.
Claim 7
Dependent Claim
29 words
The microparticle of claim 1 wherein the film-forming polymer comprises biodegradable polymer selected from the group consisting of a polylactide, a polyglycolide, or a copolymer of lactide or glycolide.
Claim 8
Dependent Claim
14 words
The microparticle of claim 1 wherein the active ingredient is a hydrophobic steroid drug.
Claim 9
Dependent Claim
31 words
The microparticle of claim 1 wherein the active ingredient is a drug selected from the group consisting of testosterone, progesterone, nonoxynol-9, povidone iodine, cholesterol, levonorgestrel, tyrosine, norethindrone, lidocaine, etidocaine and bupivcaine.
Claim 10
Dependent Claim
22 words
The microparticle of claim 1 wherein the active ingredient comprises from about 20% to 80% by weight of the composite core mateial.
Claim 11
Dependent Claim
18 words
The microparticle of claim 1 wherein the outer wall coating thickness is from about 0.1 to 20 microns.
References Cited (Backward Citations)
US3089824A
Cited
US4568559A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-17 | 1990-05-19 | 1990-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-17 | 1994-05-19 | 1994-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-17 | 1998-05-19 | 1998-11-18 | $7700.00 | Window Closed / Lapsed |