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US4957735A Expired / Lapsed US ⏱️ 0.0 years remaining

Target-sensitive immunoliposomes- preparation and characterization

Assignee: BIOWHITTAKER, INC. A CORP. OF DELAWARE
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Filing: 1987-02-09
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Granted: 1990-09-18
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Expires: 2007-02-09
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Abstract

Abstract Novel target-sensitive immunoliposomes were prepared and characterized. In this invention, target specific binding of antibody-coated liposomes was sufficient to induce bilayer destabilization, resulting in a site-specific release of liposome contents. Unilamellar liposomes were prepared by using a small quantity of palmitoyl IgG (pIgG) to stabilize the bilayer phase of the unsaturated phosphatidylethanol amine (PE) which by itself does not form stable liposomes. A mouse monoclonal IgG antibody to the glycoprotein D (gD) of Herpes Simplex Virus (HSV) and dioleoyl PE were used in one preferred embodiment. In another preferred embodiment, potentially cytotoxic antiviral drugs were entrapped in target sensitive (TS) immunoliposomes and delivered to HSV infected cells. Potency was as much as 1000 times superior to the free drug and cytotoxicity was decreased by as much as 3000 fold.

Inventors

  • 👤 Leaf Huang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-10 00:53
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/531; G01N33/532; G01N33/58; G01N33/585; G01N33/586; Y; Y10; Y10S; Y10S424/00; Y10S424/812; Y10S436/00; Y10S436/829

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 45 words
Target sensitive immunoliposomes consisting essentially of phosphatidylethanolamine and a stabilizing amount of fatty acid (C 12 to C 24 ) derivatized antibody, said antibody having an affinity for the target cell surface which immunoliposomes release their entrapped contents upon binding to a target cell surface.
Claim 2
Dependent Claim 45 words
Target sensitive immunoliposomes consisting essentially of phosphatidylethanolamine and a stabilizing amount of fatty acid (C 12 to C 24 ) derivatized antibody, said antibody having an affinity for the target cell surface which immunoliposomes release their entrapped contents upon binding to a target cell surface.
Claim 3
Dependent Claim 22 words
The target sensitive immunoliposomes of claim 1, wherein the phosphatidylethanolamine is selected from the group consisting of dioleoyl phosphatidylethanolamine and transphosphotidylated phosphtidylethanolamine.
Claim 4
Dependent Claim 16 words
The target sensitive immunoliposomes of claim 1, wherein the fatty acid is a palmitic acid derivative.
Claim 5
Dependent Claim 12 words
The target sensitive immunoliposomes of claim 1, wherein the antibody is IgG.
Claim 6
Dependent Claim 14 words
The target sensitive immunoliposomes of claim 1, wherein the antibody is a monoclonal antibody.
Claim 7
Dependent Claim 21 words
The target sensitive immunoliposome of claim 5, wherein the monoclonal antibody recognizes the glycoprotein D of the Herpes Simplex Virus (HSV).
Claim 8
Dependent Claim 18 words
The target sensitive immunoliposomes of claim 1, wherein the entrapped contents consist essentially of a pharmaceutically acceptable drug.
Claim 9
Dependent Claim 28 words
The target sensitive immunoliposomes of claim 7, wherein the pharmaceutically acceptable drug is selected from the group consisting of cytotoxic and antiviral drugs of the nucleoside analog family.
Claim 10
Dependent Claim 27 words
The target sensitive immunoliposomes of claim 8, wherein the cyclotoxic and antiviral drugs are selected from the group consisting of fluorodeoxy uridine, iododeoxyuridine, acyclovir and cytosine arabinoside.
Claim 11
Dependent Claim 13 words
The target sensitive immunoliposomes of claim 7, in a form suitable for injection.
Claim 12
Dependent Claim 14 words
The target sensitive immunoliposomes of claim 7, in a form suitable for ophthalmic application.
Claim 13
Dependent Claim 14 words
The target sensitive immunoliposomes of claim 7, in a form suitable for topical applications.
Claim 14
Dependent Claim 26 words
The target sensitive immunoliposomes of claim 1, further consisting essentially of palmitoyl IgG and phosphaticlethanolamine in a molar ratio of not less than 2.5×10 -4 .
Claim 15
Dependent Claim 19 words
The target sensitive immunoliposomes of claim 10, wherein the minimal coupling stoichimetry of palmitic acid to antibody is 2.2.
Claim 16
Independent Claim 82 words
A method of delivering therapeutic agents to the surface of cells in need of such treatment comprising the steps of: (a) forming target sensitive immunoliposomes from phosphatidylethanolamine and a stabilizing amount of fatty acid (C 12 to C 24 ) derivatized antibody, said antibody having an affinity for the target cell surface; (b) entrapping one or more therapeutic agents within the immunoliposomes of step (a); and (c) administering the immunoliposomes prepared in step (b) to a patient in need of such treatment.
Claim 17
Independent Claim 82 words
A method of delivering therapeutic agents to the surface of cells in need of such treatment comprising the steps of: (a) forming target sensitive immunoliposomes from phosphatidylethanolamine and a stabilizing amount of fatty acid (C 12 to C 24 ) derivatized antibody, said antibody having an affinity for the target cell surface; (b) entrapping one or more therapeutic agents within the immunoliposomes of step (a); and (c) administering the immunoliposomes prepared in step (b) to a patient in need of such treatment.
Claim 18
Dependent Claim 20 words
The method of claim 15, wherein the phosphatidylethanolamine is selected from the group consisting of dioleoyl phosphatidylethanolamine and transphosphotidylated phosphatidylethanolamine.
Claim 19
Dependent Claim 14 words
The method of claim 15, wherein the fatty acid is a palmitic acid derivative.
Claim 20
Dependent Claim 10 words
The method of claim 15, wherein the antibodys is IgG.
Claim 21
Dependent Claim 12 words
The method of claim 15, wherein the antibody is a monoclonal antibody.
Claim 22
Dependent Claim 18 words
The method of claim 19, wherein the monoclonal recognizes the glycoprotein D of the Herpes Simplex Virus (HSV).

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-09-17 1994-03-19 1994-09-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-09-17 1998-03-19 1998-09-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-09-17 2002-03-19 2002-09-18 $7700.00 Window Closed / Lapsed

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