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Drug delivery system and method of making the same

Assignee: SOUTHERN RESEARCH INSTITUTE PO BOX 55305 BIRMINGHAM ALABAMA 35255-5305
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Filing: 1987-08-03
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Granted: 1990-01-30
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Expires: 2007-08-03
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Abstract

Abstract A compatible, biodegradable microcapsule delivery system for active ingredients, including hormonally active peptides, proteins, or other bioactive molecules, and a method of making the same. The ingredients are encapsulated in biodegradable copolymer excipients of varying mole ratios and the blend of the microcapsules are administered to an animal. Delivery of the ingredient occurs over a prolonged period of time at a constant rate as a result of the varying break-down rates of the copolymer excipients.

Inventors

  • 👤 Thomas R. Tice
  • 👤 Richard M. Gilley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 18:11
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5084; A61K38/00; A61K38/04; A61K38/08; A61K38/09; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 118 words
A method of preparing a composition for delivering a an effective amount of a constant dose of an active ingredient to an animal over a preselected, prolonged period of time, comprising the steps of: (a) encapsulating effective amounts of said ingredient in first and second separate biodegradable and biocompatible copolymer excipients having different monomers ratios to form first and second microcapsules, each of said microcapsules having of a different rate of release therefrom of said ingredient; and (b) combining an effective amount of said first and second microcapsules to form said composition having a delivery profile wherein the release of said ingredient through said second microcapsule begins as the release of said ingredient through said first microcapsule declines.
Claim 2
Independent Claim 118 words
A method of preparing a composition for delivering a an effective amount of a constant dose of an active ingredient to an animal over a preselected, prolonged period of time, comprising the steps of: (a) encapsulating effective amounts of said ingredient in first and second separate biodegradable and biocompatible copolymer excipients having different monomers ratios to form first and second microcapsules, each of said microcapsules having of a different rate of release therefrom of said ingredient; and (b) combining an effective amount of said first and second microcapsules to form said composition having a delivery profile wherein the release of said ingredient through said second microcapsule begins as the release of said ingredient through said first microcapsule declines.
Claim 3
Dependent Claim 22 words
A method as claimed in claim 1, further including the step of administering an effective amount of said composition to the animal.
Claim 4
Dependent Claim 34 words
A method as claimed in claim 1, wherein said excipient is selected from the group consisting of polyacetal polymers, polyorthoesters, polyesteramides, polycaprolactone and copolymers thereof, polycarbonates, polyhydroxybuterate and copolymers thereof, polymaleamides, copolyaxalates, and polysaccharides.
Claim 5
Dependent Claim 13 words
The method as claimed in claim 1, wherein a copolymer excipient is poly(D,L-lactide-co-glycolide).
Claim 6
Dependent Claim 23 words
The method as claimed in claim 5, wherein the copolymer excipients have mole ratios of lactide to glycolide of 40:60 to 85:15, respectively.
Claim 7
Dependent Claim 15 words
The method as claimed in claim 1, wherein said active ingredient is a bioactive molecule.
Claim 8
Dependent Claim 14 words
The method as claimed in claim 1, wherein said active ingredient is a peptide.
Claim 9
Dependent Claim 11 words
The method of claim 7, wherein said peptide is hormonally active.
Claim 10
Dependent Claim 20 words
The method as claimed in claim 7, wherein said peptide is a luteinizing hormone releasing hormone or an analogue thereof.
Claim 11
Dependent Claim 12 words
The method of claim 1, wherein said active ingredient is a protein.
Claim 12
Dependent Claim 18 words
The method as claimed in claim 7, wherein said peptide is [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide.
Claim 13
Dependent Claim 76 words
The method as claimed in claim 1, wherein said first microcapsule comprises 3 percent by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 52 percent lactide to 48 percent glycolide and wherein said second microcapsule comprises 10 percent by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 68 percent lactide to 32 percent glycolide.
Claim 14
Dependent Claim 50 words
The method as claimed in claim 12, wherein said combining step further comprises adding to said composition an effective amount of 8 percent by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 85 percent lactide to 15 percent glycolide.
Claim 15
Dependent Claim 34 words
The method as claimed in claim 13, wherein [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide is delivered at a constant rate ranging from 50 μg to 250 μg per day for approximately 180 days.
Claim 16
Dependent Claim 20 words
The method as claimed in claim 7, wherein said peptide is [D-N-Ac-4-Cl-Phe 2 , D-Trp 6 , D-Ala 10 ]-LHRH.
Claim 17
Dependent Claim 38 words
The method as claimed in claim 15, wherein said [D-N-Ac-4-Cl-Phe 2 , D-Trp 6 , D-Ala 10 ]-LHRH is delivered at a constant rate of about 200 μg to 500 μg per day for at least 90 days.
Claim 18
Dependent Claim 13 words
The method as claimed in claim 1, wherein said administering step is parenterally.
Claim 19
Dependent Claim 13 words
The method as claimed in claim 1, wherein said administering step is intramuscularly.
Claim 20
Dependent Claim 97 words
A composition capable of delivering an effective amount of a constant dose of an active ingredient to an animal over a preselected, prolonged period of time, comprising a blend of effective amounts of an active ingredient encapsulated in at least two biodegradable and biocompatible copolymer excipients having different monomers ratios to form first and second microcapsules, each excipient having of a different rate of release of said ingredient therethrough, said composition having a delivery profile wherein the release of said ingredient through said second microcapsule begins as the release of said ingredient through said first microcapsule declines.
Claim 21
Dependent Claim 97 words
A composition capable of delivering an effective amount of a constant dose of an active ingredient to an animal over a preselected, prolonged period of time, comprising a blend of effective amounts of an active ingredient encapsulated in at least two biodegradable and biocompatible copolymer excipients having different monomers ratios to form first and second microcapsules, each excipient having of a different rate of release of said ingredient therethrough, said composition having a delivery profile wherein the release of said ingredient through said second microcapsule begins as the release of said ingredient through said first microcapsule declines.
Claim 22
Dependent Claim 13 words
A composition as claimed in claim 19, wherein said copolymer excipients are poly(D,L-lactide-co-glycolide).
Claim 23
Dependent Claim 23 words
A composition as claimed in claim 20, wherein said copolymer excipients have mole ratios of lactide to glycolide of 40:60 to 85:15 respectively.
Claim 24
Dependent Claim 15 words
A composition as claimed in claim 19, wherein said active ingredient is a bioactive molecule.
Claim 25
Dependent Claim 14 words
A composition as claimed in claim 19, wherein said active ingredient is a peptide.
Claim 26
Dependent Claim 13 words
A composition as claimed in claim 23, wherein said peptide is hormonally active.
Claim 27
Dependent Claim 20 words
A composition as claimed in claim 23, wherein said peptide is a luteinizing hormone releasing hormone or an analog thereof.
Claim 28
Dependent Claim 21 words
A composition as claimed in claim 25, wherein said luteinizing hormone releasing hormone is [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide.
Claim 29
Dependent Claim 14 words
A composition as claimed in claim 19, wherein said active ingredient is a protein.
Claim 30
Dependent Claim 72 words
A composition as claimed in claim 19, wherein said blend of microencapsulated peptide is comprised of appropriate amounts of 3% by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 52% lactide to 48% glycolide, and 10% by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 68% lactide to 32% glycolide.
Claim 31
Dependent Claim 44 words
A composition as claimed in claim 28 and further comprising an appropriate amount of 8% by weight loaded [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide encapsulated in a copolymer excipient having a mole ratio of 85% lactide to 15% glycolide added to said blend.
Claim 32
Dependent Claim 34 words
A composition as claimed in claim 29, wherein said blend delivers [D-Trp 6 , des-Gly 10 ]-LHRH ethylamide at a constant rate of about 50 μg to 250 μg per day for 180 days.
Claim 33
Dependent Claim 20 words
A composition as claimed in claim 23, wherein said peptide is [D-N-Ac-4-Cl-Phe 2 , D-Trp 6 , D-Ala 10 ]-LHRH.
Claim 34
Dependent Claim 38 words
A composition as claimed in claim 31, wherein said blend delivers [D-N-Ac-4-Cl-Phe 2 , D-Trp 6 , D-Ala 10 ]-LHRH at a constant rate of about 200 μg to 500 μg per day for at least 90 days.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-01-29 1993-07-31 1994-01-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-01-29 1997-07-31 1998-01-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-01-29 2001-07-31 2002-01-30 $7700.00 Window Closed / Lapsed

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