EP0132384A2
Expired / Lapsed
EP
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Controlled release device
Assignee: BTG International Ltd
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Filing: 1984-07-19
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Granted: —
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Expires: 2004-07-19
Abstract
Abstract A controlled release device which comprises: (i) a hydrogel; and incorporated therewith (ii) an active substance, at least part of at least one surface of the device comprising (iii) a layer which is impermeable to aqueous media.
Inventors
- 👤 Neil Bonette Graham
- 👤 Marion Eileen Mcneill
- 👤 David Anthony Wood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 16:32
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0087; A61K9/0092; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2027; A61K9/2031; A61M; A61M31/00; A61M31/002; C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G18/4833; C08G18/65; C08G18/66; C08G18/6666; C08G18/667; C08G18/6674; C08G18/6677; C08G2210/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
37 words
A controlled release device which comprises: (i) a hydrogel; and incorporated therewith (ii) an active substance, at least part of at least one surface of the device comprising (iii) a layer which is impermeable to aqueous media.
Claim 2
Dependent Claim
37 words
A controlled release device which comprises: (i) a hydrogel; and incorporated therewith (ii) an active substance, at least part of at least one surface of the device comprising (iii) a layer which is impermeable to aqueous media.
Claim 3
Dependent Claim
92 words
A controlled release device according to Claim 1 wherein the hydrogel (i) comprises a hydrophilic homo- or copolymer comprising residues derivable from at least one of the following monomer classes: (a) (meth)acrylic acid, (meth)acrylamide or an unsubstituted or hydroxy-substitued alkyl (meth)acrylate or a poly(oxyethylene)(meth)acaylate; (b) a substituted or unsubstituted cyclic mono or poly ether having from 3 to 6 ring atoms or cyclic imine having 3 ring atoms; or (c) a substituted or unsubstituted vinyl alcohol, aldehyde, ether, acetal, ketone, ester, anhydride or substituted or unsubstituted N- or C- vinyl heterocyclic compound.
Claim 4
Dependent Claim
20 words
A controlled release device according to Claim 1 or 2 wherein the hydrogel (i) comprises a homo- or copoly(alkylene oxide).
Claim 5
Dependent Claim
16 words
A controlled release device according to Claim 3 wherein the hydrogel (i) comprises a poly(ethylene oxide).
Claim 6
Dependent Claim
25 words
A controlled release device according to Claim 3 or 4 wherein the poly(alkylene oxide) is cross-linked through reaction with isocyanate or unsaturated cyclic ether groups.
Claim 7
Dependent Claim
18 words
A controlled release device according to any preceding claim wherein the active substance (ii) comprises a lithium salt.
Claim 8
Dependent Claim
17 words
A controlled release device according to any preceding claim wherein the active substance (ii) comprises a prostaglandin.
Claim 9
Dependent Claim
23 words
A controlled release device according to any preceding claim wherein the active substance (ii) is homogeneously or inhomogenously dispersed throughout the hydrogel (i).
Claim 10
Dependent Claim
23 words
A controlled release device according to any preceding claim wherein the active substance (ii) is contained in a reservoir within the hydrogel (i).
Claim 11
Dependent Claim
25 words
A controlled release device according to any preceding claim which is formed as a rod, slab, film hemisphere and/or is of hollow or sinusoidal profile.
Claim 12
Dependent Claim
16 words
A controlled release device according to any preceding claim wherein the impermeable layer (iii) is hydrophobic.
Claim 13
Dependent Claim
22 words
A controlled release device according to any preceding claim where the impermeable layer (iii) is also impermeable to the active substance (ii).
Claim 14
Dependent Claim
41 words
A controlled release device according to any preceding claim where the impermeable layer (iii) covers all of at least one surface of the device thereby defining at least one orifice thereon through which the hydrogel (i) is contactable by aqueous media.
Claim 15
Dependent Claim
36 words
14 A controlled release device according to any preceding claim which comprises a rod, slab or film of hydrogel (i) wherein the impermeable layer (iii) covers all of the surfaces except one or both end profiles.
Claim 16
Dependent Claim
28 words
A controlled release device according to any preceding claim wherein the rod or slab of hydrogel (i) is formed with a single or bis-sinusoidal profile along its length.
Claim 17
Dependent Claim
32 words
A controlled release according to any of Claims 1 to 13 which comprises a hemisphere of hydrogel (i) wherein the impermeable layer (iii) covers all of the surfaces except a polar orifice.
Claim 18
Dependent Claim
10 words
A controlled release device according to any of Claims 1
Claim 19
Dependent Claim
20 words
to 12 which comprises a ring of hydrogel (i) wherein the impermeable layer (iii) covers all of the external surfaces.
Claim 20
Dependent Claim
20 words
to 12 which comprises a ring of hydrogel (i) wherein the impermeable layer (iii) covers all of the external surfaces.
Claim 21
Dependent Claim
16 words
A controlled release device according to any of the preceding claims comprising a plurality of orifices.
References Cited (Backward Citations)
No citation records indexed.
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