US4356166A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time-release chemical delivery system
Assignee: University of Utah Research Foundation Inc
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Filing: 1978-12-08
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Granted: 1982-10-26
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Expires: 1998-12-08
Abstract
Abstract A time-release chemical delivery system in which a bioactive compound is attached to a polymeric biodegradable carrier by a hydrolyzable bond is disclosed. The bioactive compound can either be bound directly to the polymer or be attached to the polymer via a spacer group. The composition of the system is particularly effective for delivering medication systemically to a host animal over a prolonged period of time after being surgically implanted or injected subcutaneously. Biodegradable condensation polymers having reactive pendant groups, for example, poly-L-(glutamic acid), or derivatized poly-L-(glutamic acid) are effective as polymeric carriers.
Inventors
- 👤 Robert V. Peterson
- 👤 James M. Anderson
- 👤 Donald E. Gregonis
- 👤 Sunj-Wan Kim
- 👤 Jan Feijen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:48
CPC Classifications
A; A61; A61K; A61K47/00; A61K47/50; A61K47/51; A61K47/62; A61K47/64; A61K47/645
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
83 words
A time release chemical delivery system for implantation in animal host comprising: a polymeric, water-insoluble, biodegradable polymer which biodegrades into fragments tolerable by the host; and a bioactive compound chemically attached to said carrier by a hydrolyzable bond, said bioactive compound containing a group which reacts with a group on the biodegradable polymer to form a hydrolyzable bond and being effective in small dosages to produce a biological effect within said host upon release into the host by hydrolysis of the hydrolyzable bond.
Claim 2
Dependent Claim
83 words
A time release chemical delivery system for implantation in animal host comprising: a polymeric, water-insoluble, biodegradable polymer which biodegrades into fragments tolerable by the host; and a bioactive compound chemically attached to said carrier by a hydrolyzable bond, said bioactive compound containing a group which reacts with a group on the biodegradable polymer to form a hydrolyzable bond and being effective in small dosages to produce a biological effect within said host upon release into the host by hydrolysis of the hydrolyzable bond.
Claim 3
Dependent Claim
18 words
The chemical delivery system of claim 1 wherein said polymer is a condensation polymer having reactive pendant groups.
Claim 4
Dependent Claim
20 words
The chemical delivery system of claim 1 wherein said polymer has a molecular weight of about 5,000 to about 1,000,000.
Claim 5
Dependent Claim
21 words
The chemical delivery system of claim 1 wherein said polymer is a polymer or copolymer of glutamic acid or aspartic acid.
Claim 6
Dependent Claim
24 words
The chemical delivery system of claim 2 wherein at least one percent (1%) of said reactive pendant sites are coupled to a reactive compound.
Claim 7
Dependent Claim
25 words
The chemical delivery system of claim 1 wherein said bioactive compound is indirectly coupled to said carrier by a hydrolyzable bond to a spacer compound.
Claim 8
Dependent Claim
15 words
The chemical delivery system of claim 6 wherein said spacer is substantially a linear compound.
Claim 9
Dependent Claim
21 words
The chemical delivery system of claim 7 wherein said spacer compound is coupled to said bioactive compound by a hydrolyzable bond.
Claim 10
Dependent Claim
17 words
The chemical delivery system of claim 2 wherein the carrier is a polyester, polyamide or polyurethane polymer.
Claim 11
Dependent Claim
20 words
The time release chemical delivery system of claim 1 wherein said hydrolyzable bond is an ester, amide or urethane bond.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-25 | 1986-04-26 | 1986-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-25 | 1990-04-26 | 1990-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-25 | 1994-04-26 | 1994-10-26 | $7700.00 | Window Closed / Lapsed |