# US 2008/0188571 A1 · Drug delivery system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0188571 A1 - Document ID: US20080188571A1 - Status: Published application - Kind: A1 - Application number: 12/011,773 - Filed: 2008-01-28 - Published: 2008-08-07 - Earliest claimed: 2000-12-14 - Assignees: Isis Innovation Limited - Inventors: Dermot Michael O'Hare - Web page: https://patentgrep.com/patent/US20080188571A1 ## CPC - A61K 9/14: Particulate form, e.g. powders, {Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles (microspheres A61K9/16; microcapsules A61K9/50; nanocapsules, nanoparticles of the matrix type A61K9/51)} - A61K 9/143: {with inorganic compounds} - A61K 31/19: Carboxylic acids, e.g. valproic acid (salicylic acid A61K31/60) - A61K 31/192: having aromatic groups, e.g. sulindac, 2-aryl-propionic acids, ethacrynic acid {(cannabinoids A61K31/658)} - A61K 31/196: the amino group being directly attached to a ring, e.g. anthranilic acid, mefenamic acid, diclofenac, chlorambucil - A61K 33/08: Oxides; Hydroxides - A61K 33/10: Carbonates; Bicarbonates - A61K 47/6949: {inclusion complexes, e.g. clathrates, cavitates or fullerenes} - B82Y 5/00: Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract A drug delivery system for the controlled release of a pharmaceutically-active compound by oral route comprises an intercalate of a layered double hydroxide having, before intercalation, layers of metal hydroxides, and having intercalated therein a pharmaceutically-active compound having at least one anionic group. A preferred layered double hydroxide is one that has layers which comprise [LiAl2(OH)6]+. The drug delivery system has use in the delivery of drugs such as 4-biphenylacetic acid, Diclofenac, Gemfibrozil, Ibuprofen, Naproxen, 2-Propylpentanoic acid and Tolfenamic acid. ## Claims ### Claim 1 A drug delivery system comprising an intercalate of a layered double hydroxide having, before intercalation, layers of metal hydroxides, and having intercalated therein a pharmaceutically-active compound having at least one anionic group. ### Claim 2 (depends on 1) The system according to claim 1 wherein the layered double hydroxide, before intercalation, is represented by the general formula [MII(1-x)MIIIx(OH)2]x+[An−x/n] in which MII is a divalent metal cation; MIII a trivalent metal cation; A is a displaceable anion; n is an integer; and x is a number less than 1, which compound is optionally hydrated with a stoichiometric amount or a non-stoichiometric amount of water. ### Claim 3 (depends on 2) The system according to claim 2, wherein MII Mg or Ca and MIII is Al. ### Claim 4 (depends on 2) The system according to claim 2, wherein A is selected from OH, F, Cl, Br, I, SO4, and NO3. ### Claim 5 (depends on 1) The system according to claim 1, wherein the layered double hydroxide, before intercalation, is represented by the general formula [MIMIII2(OH)6]+[An−1/n] in which MI is a monovalent metal cation; MIII a trivalent metal cation; A is a displaceable anion; and n is an integer, which compound is optionally hydrated with a stoichiometric or non-stoichiometric amount of water. ### Claim 6 (depends on 5) The system according to claim 5, wherein MI is Li and MIII is Al. ### Claim 7 (depends on 5) The system according to claim 5, wherein A is selected from OH, F, Cl, Br, I, SO4, and NO3. ### Claim 8 (depends on 7) The system according to claim 7, wherein the layered double hydroxide is [LiAl2[(OH)]6Cl.H20. ### Claim 9 (depends on 1) The system according to claim 1, wherein the pharmaceutically-active compound having at least one anionic group is pharmaceutically-active compound containing at least one carboxylic acid group or a non-toxic salt thereof. ### Claim 10 (depends on 1) The system according to claim 1, which additionally comprises a non-toxic compound having an anion which is capable of displacing the pharmaceutically-active compound from the intercalate. ### Claim 11 (depends on 10) The system according to claim 10, wherein the non-toxic compound is selected from magnesium carbonate, magnesium hydrogen carbonate, calcium carbonate or calcium hydrogen carbonate. ### Claim 12 (depends on 1) The system according to claim 1, wherein the pharmaceutically-active compound is selected from 4-biphenylacetic acid, Diclofenac, Gemfibrozil, Ibuprofen, Naproxen, 2-propylpentanoic acid and Tolfenamic acid. ### Claim 13 A method of making an intercalate of a layered double hydroxide having, intercalated therein, a pharmaceutical-active compound having at least one anionic group which comprises treating an aqueous solution of the pharmaceutically-active compound, optionally in the form of a non-toxic salt thereof, with the layered double hydroxide and separating the intercalate of the layered double hydroxide. ### Claim 14 (depends on 13) The method according to claim 13, wherein the layered double hydroxide, before intercalation, is represented by the general formula [MII(1-x)MIIIx(OH)2]x+[An−x/n] in which MII is a divalent metal cation; MIII a trivalent metal cation; A is a displaceable anion; n is an integer; and x is a number less than 1, which compound is optionally hydrated with a stoichiometric amount or a non-stoichiometric amount of water. ### Claim 15 (depends on 14) A method according to claim 14, wherein MII is Mg and MIII is Al. ### Claim 16 (depends on 14) The method according to claim 14, wherein A is selected from OH, F, Cl, Br, I, SO4, and NO3. ### Claim 17 (depends on 13) The method according to claim 13, wherein the layered double hydroxide, before intercalation, is represented by the general formula [MIMIII2(OH)6]+[An−1/n] in which MII is a monovalent metal cation; MIII a trivalent metal cation; A is a displaceable anion; and n is an integer, which compound is optionally hydrated with a stoichiometric or non-stoichiometric amount of water. ### Claim 18 (depends on 17) The method according to claim 17, wherein MI is Li and MIII is Al. ### Claim 19 The method according to claim, wherein A is selected from OH, F, Cl, Br, I, SO4, and NO3. ### Claim 20 (depends on 19) The method according to claim 19, wherein the layered double hydroxide is [LiAl2[(OH)]6Cl.H20. ### Claim 21 (depends on 13) The method according to claim 13, wherein the pharmaceutically-active compound having at least one anionic group is a pharmaceutically-active compound containing at least one carboxylic acid group or a non-toxic salt thereof. ### Claim 22 (depends on 21) The method according to claim 21 wherein the pharmaceutically-active compound is selected from 4-biphenylacetic acid, Diclofenac, Gemfibrozil, Ibuprofen, Naproxen, 2-propylpentanoic acid and Tolfenamic acid.