US4749570A
Expired / Lapsed
US
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Targeting conjugates of albumin and therapeutic agents
Assignee: University of Alberta
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Filing: 1985-12-31
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Granted: 1988-06-07
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Expires: 2005-12-31
Abstract
Abstract The invention provides a conjugate comprising an enzyme having its antigenic sites or antigenicity masked by albumin and having a targeting agent attached, and a method for its preparation. The albumin is included in an amount sufficient to mask antigenicity of the enzyme. The targeting agent used has binding specificity for receptor sites on cells towards which it is desirable to direct the enzyme. Insulin, immunoglobulin G, antibody against human pancreatic tumor cell, and antibody against hyaluronic acid are exemplified as targeting agents.
Inventors
- 👤 Mark J. Poznansky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:22
CPC Classifications
A; A61; A61K; A61K38/00; A61K38/16; A61K38/43; A61K38/46; A61K38/47; A61K38/44; A61K38/446; A61K38/50; A61K47/00; A61K47/50; A61K47/51; A61K47/62; A61K47/64; A61K47/643; A61K47/68; A61K47/6835; A61K47/6849; C; C07; C07K; C07K16/00; C07K16/18; C07K16/28; C07K16/2803; C07K16/2833; C07K16/30; C07K16/303; C12; C12Y; C12Y115/00; C12Y115/01; C12Y115/01001; C12Y302/00; C12Y302/01; C12Y302/0102; C12Y305/00; C12Y305/01; C12Y305/01001; C07K2317/00; C07K2317/50; C07K2317/54; Y; Y10; Y10S; Y10S424/00; Y10S424/809
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
72 words
A water soluble, sterile and non-immunogenic composition of matter, comprising an enzyme selected from the group consisting of α-1,4-glucosidase, L-asparaginase, and superoxide dismutase, said enzyme chemically linked to homologous albumin, and a targeting agent chemically linked to the albumin, the amount of albumin being sufficient to mask antigenicity of the enzyme, and the targeting agent having binding specificity for receptor sites on cells to which it is desirable to direct the enzyme.
Claim 2
Dependent Claim
72 words
A water soluble, sterile and non-immunogenic composition of matter, comprising an enzyme selected from the group consisting of α-1,4-glucosidase, L-asparaginase, and superoxide dismutase, said enzyme chemically linked to homologous albumin, and a targeting agent chemically linked to the albumin, the amount of albumin being sufficient to mask antigenicity of the enzyme, and the targeting agent having binding specificity for receptor sites on cells to which it is desirable to direct the enzyme.
Claim 3
Dependent Claim
25 words
The composition as set forth in claim 1, wherein the targeting agent is selected from the group consisting of serum hormones and cell specific antibodies.
Claim 4
Dependent Claim
14 words
The composition as set forth in claim 1, wherein the targeting agent is insulin.
Claim 5
Dependent Claim
21 words
The composition as set forth in claim 1, wherein the targeting agent is an antibody directed against human pancreatic tumor cells.
Claim 6
Dependent Claim
15 words
The composition as set forth in claim 1, wherein the targeting agent is an immunoglobulin.
Claim 7
Dependent Claim
22 words
The composition as set forth in claim 1, wherein the targeting agent is the (Fab') 2 fragment of an immunoglobulin G molecule.
Claim 8
Dependent Claim
21 words
The composition as set forth in claim 3, wherein the enzyme is selected from the group consisting of α-1,4-glucosidase and L-asparaginase.
Claim 9
Dependent Claim
13 words
The composition as set forth in claim 4, wherein the enzyme is L-asparaginase.
Claim 10
Dependent Claim
21 words
The composition as set forth in claim 5, wherein the enzyme is selected from the group consisting of α-1,4-glucosidase and L-asparaginase.
Claim 11
Dependent Claim
21 words
The composition as set forth in claim 6, wherein the enzyme is selected from the group consisting of α-1,4-glucosidase and L-asparaginase.
Claim 12
Dependent Claim
24 words
The composition as set forth in claim 1, wherein the targeting agent is an antibody against hyaluronic acid, and the enzyme is superoxide dismutase.
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) | 1991-06-07 | 1991-12-07 | 1992-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-07 | 1995-12-07 | 1996-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-07 | 1999-12-07 | 2000-06-07 | $7700.00 | Window Closed / Lapsed |