US4906474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bioerodible polyanhydrides for controlled drug delivery
Assignee: Massachusetts Institute of Technology
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Filing: 1984-05-21
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Granted: 1990-03-06
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Expires: 2004-05-21
Abstract
Abstract A composition of matter suitable for implantation in the body to effect zero order drug release comprising a drug and a polymer of the formula: ##STR1## wherein R and R' can be the same or different and are hydrophobic organic linkages and n and m are integers of 1 or greater.
Inventors
- 👤 Robert S. Langer
- 👤 Howard Rosen
- 👤 Robert J. Linhardt
- 👤 Kam Leong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:01
CPC Classifications
C; C08; C08G; C08G67/00; C08G67/04; A; A61; A61L; A61L17/00; A61L17/06; A61L17/10; A61L27/00; A61L27/14; A61L27/18; A61L27/50; A61L27/58
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
115 words
A composition of matter comprising a mixture of a therapeutic drug and a polymer of the formula: ##STR10## wherein R and R' can be the same or different and are hydrophobic organic linkages, the sum of n and m is between 10 and 106, and said polymer is polymerized from prepolymers formed from dicarboxylic acids, wherein the prepolymers are purified by recrystallization until the contaminants and degradation products present in the prepolymer are removed, said polymer being characterized by biocompatibility that results in minimal tissue irritation when implanted in vasculated tissue, and approximately zero order erosion and release rates of drug in vivo as a function of hydrolysis of the anhydride linkages in the polyanhydride.
Claim 2
Dependent Claim
115 words
A composition of matter comprising a mixture of a therapeutic drug and a polymer of the formula: ##STR10## wherein R and R' can be the same or different and are hydrophobic organic linkages, the sum of n and m is between 10 and 106, and said polymer is polymerized from prepolymers formed from dicarboxylic acids, wherein the prepolymers are purified by recrystallization until the contaminants and degradation products present in the prepolymer are removed, said polymer being characterized by biocompatibility that results in minimal tissue irritation when implanted in vasculated tissue, and approximately zero order erosion and release rates of drug in vivo as a function of hydrolysis of the anhydride linkages in the polyanhydride.
Claim 3
Dependent Claim
31 words
The composition of claim 1 wherein R and R' are selected from the group consisting of an alkyl from 1 to 20 carbon atoms, p-carboxyphenoxymethane, benzyl, pyridine, and aromatic amino acids.
Claim 4
Dependent Claim
21 words
The composition of claim 2 wherein the amino acid is selected from the group consisting of phenylanine, tyrosine, tryptophan, and glycine.
Claim 5
Dependent Claim
21 words
The composition of claim 1 wherein the drug is selected from the group consisting of biologically active proteins, steroids, and antibiotics.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-05 | 1993-09-04 | 1994-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-05 | 1997-09-04 | 1998-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-05 | 2001-09-04 | 2002-03-06 | $7700.00 | Window Closed / Lapsed |