EP0481732A1
Expired / Lapsed
EP
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Prolonged release preparation and polymers thereof
Assignee: Takeda Pharmaceutical Co Ltd
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Filing: 1991-10-15
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Granted: —
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Expires: 2011-10-15
Abstract
Abstract 1. A polymer for a prolonged release preparation which comprises (A) a polylactic acid and (B) a copolymer of glycolic acid and a hydroxycarboxylic acid of general formula wherein R stands for an alkyl group having 2 to 8 carbons, and wherein the weight ratio of (A) and (B) is in the range of 10/90 to 90/10. The drug is released at a constant rate from the preparation over the total release period without a large burst at the initial stage. Furthermore, the drug release period of the preparation can be freely controlled by varying the blending ratio of (A) and (B).
Inventors
- 👤 Minoru Yamada
- 👤 Seiko Ishiguro
- 👤 Yasuaki Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 08:42
CPC Classifications
A; A61; A61K; A61K31/00; A61K31/74; A61K31/745; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5031; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; C; C08; C08L; C08L67/00; C08L67/04
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
56 words
A polymer for a prolonged release preparation which comprises (A) a polylactic acid and (B) a copolymer of glycolic acid and a hydroxycarboxylic acid of the formula wherein R stands for an alkyl group having 2 to 8 carbons, and wherein the weight ratio of (A) and (B) is in the range of 10/90 through 90/10.
Claim 2
Dependent Claim
19 words
The polymer according to claim 1, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid.
Claim 3
Dependent Claim
32 words
The polymer according to claim 1, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid, and the mole ratio of D- and L-lactic acid is 45/55 to 25/75.
Claim 4
Dependent Claim
24 words
The polymer according to claim 1, wherein the polylactic acid has a molecular weight peak value of 5000 to 30000 as determined by GPC.
Claim 5
Dependent Claim
32 words
The polymer according to claim 1, wherein the hydroxycarboxylic acid is a member selected from the group consisting of 2-hydroxybutylic acid, 2-hydroxyvaleric acid, 2-hydroxy-3-methylbutylic acid, 2-hydroxycaproic acid, 2-hydroxyisocaproic acid and 2-hydroxycaprylic acid.
Claim 6
Dependent Claim
42 words
The polymer according to claim 1, wherein the copolymer is a copolymer in which the proportion of glycolic acid is in the range of 40 to 70 mole% and the proportion of the said hydroxycarboxylic acid is 60 to 30 mole%, respectively.
Claim 7
Dependent Claim
23 words
The polymer according to claim 1, wherein the copolymer has a molecular weight peak value of 5000 to 20000 as determined by GPC.
Claim 8
Independent Claim
52 words
A method of producing a polymer for a prolonged release preparation which comprises mixing (A) a polylactic acid and (B) a copolymer of glycolic acid and a hydroxycarboxylic acid of the formula wherein R stands for an alkyl group having 2 to 8 carbons, in a weight ratio of 10/90 to 90/10.
Claim 9
Dependent Claim
19 words
The method according to claim 8, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid.
Claim 10
Dependent Claim
32 words
The method according to claim 8, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid, and the mole ratio of D- and L-lactic acid is 45/55 to 25/75.
Claim 11
Dependent Claim
24 words
The method according to claim 8, wherein the polylactic acid has a molecular weight peak value of 5000 to 30000 as determined by GPC.
Claim 12
Dependent Claim
32 words
The method according to claim 8, wherein the hydroxycarboxylic acid is a member selected frosm the group consisting of 2-hydroxybutylic acid, 2-hydroxyvaleric acid, 2-hydroxy-3-methylbutylic acid, 2-hydroxycaproic acid, 2-hydroxyisocaproic acid and 2-hydroxycaprylic acid.
Claim 13
Dependent Claim
46 words
The method according to claim 8, wherein the copolymer is a copolymer in which the proportion of glycolic acid is in the range of 40 to 70 mole% and the proportion of the said hydroxycarboxylic acid is in the range of 60 to 30 mole%, respectively.
Claim 14
Dependent Claim
23 words
The method according to claim 8, wherein the copolymer has a molecular weight peak value of 5000 to 20000 as determined by GPC.
Claim 15
Dependent Claim
67 words
A prolonged release preparation which comprises a water-soluble drug being dispersed in a polymer for a prolonged release preparation comprising (A) a polylactic acid and (B) a copolymer of glycolic acid and a hydroxycarboxylic acid of the formula wherein R stands for an alkyl group having 2 to 8 carbons, and wherein the weight ratio of (A) and (B) is in the range of 10/90 through 90/10.
Claim 16
Dependent Claim
21 words
The prolonged release preparation according to claim 15, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid.
Claim 17
Dependent Claim
33 words
The prolonged release preparation according to claim 15, wherein the polylactic acid is a polymer of D-lactic acid and L-lactic acid, the mole ratio of D- and L-lactic acid is 45/55 to 25/75.
Claim 18
Dependent Claim
26 words
The prolonged release preparation according to claim 15, wherein the polylactic acid has a molecular weight peak value of 5000 to 30000 as determined by GPC.
Claim 19
Dependent Claim
34 words
The prolonged release preparation according to claim 15, wherein the hydroxycarboxylic acid is a member selected from the group consisting of 2-hydroxybutylic acid, 2-hydroxyvaleric acid, 2-hydroxy-3-methylbutylic acid, 2-hydroxycaproic acid, 2-hydroxyisocaproic acid and 2-hydroxycaprylic acid.
Claim 20
Dependent Claim
47 words
The prolonged release preparation according to claim 15, wherein the copolymer is a copolymer in which the proportion of glycolic acid is in the range of 40 to 70 mole% the proportion of the said hydroxycarboxylic acid is in the range of 60 to 30 mole%, respectively.
Claim 21
Dependent Claim
25 words
The prolonged release preparation according to claim 15, wherein the copolymer has a molecular weight peak value of 5000 to 20000 as determined by GPC.
Claim 22
Dependent Claim
17 words
The prolonged release preparation according to claim 15, wherein the water-soluble drug is a physiologically active polypeptide.
Claim 23
Dependent Claim
21 words
The prolonged release preparation according to claim 22, wherein the physiologically active polypeptide is leutenizing hormone-releasing hormone or its functional analogs.
Claim 24
Dependent Claim
76 words
The prolonged release preparation according to claim 23, wherein the functional analogs of leutenizing hormone-releasing hormone are compounds of the formula (Pyr)Glu-R₁-Trp-Ser-R₂-R₃-R₄-Arg-Pro-R₅ wherein R₁ means His, Tyr, Trp or p-NH₂-Phe; R₂ means Tyr or Phe; R₃ means Gly or a D-amino acid residue; R₄ means Leu, Ile or Nle; R₅ means Gly-NH-R₆ (R₆ is H or a lower alkyl group which may optionally have hydroxyl group) or NH-R₆ (R₆ is as defined above) or salts thereof.
Claim 25
Dependent Claim
18 words
The prolonged release preparation according to claim 22, wherein the physiologically active polypeptide is (Pyr)Glu-His-Trp-Ser-Trp-D-Leu-Leu-Arg-Pro-NH-C₂H₅ or acetate thereof.
References Cited (Backward Citations)
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