# US 8,772,248 B2 · 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 8,772,248 B2 - Document ID: US8772248B2 - Status: Granted - Kind: B2 - Application number: 10/585,864 - Filed: 2005-01-17 - Published: 2008-06-12 - Granted: 2014-07-08 - Earliest claimed: 2004-01-17 - Assignees: Keele University - Applicants: Patrick Dawson Bailey - Inventors: Patrick Dawson Bailey - Web page: https://patentgrep.com/patent/US8772248B2 ## CPC - C07K 5/06026: {the side chain containing 0 or 1 carbon atom, i.e. Gly or Ala} - A61K 47/54: the modifying agent being an organic compound - A61K 47/64: Drug-peptide, drug-protein or drug-polyamino acid conjugates, i.e. the modifying agent being a peptide, protein or polyamino acid which is covalently bonded or complexed to a therapeutically active agent (peptidic linkers A61K47/65) - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - 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) ## Abstract A compound comprises a thiopeptide, or derivative or analogue thereof, the thiopeptide comprising a C-terminal carboxylic acid group, and a functional group for attachment to a drug, characterized in that the compound is adapted to carry or transport a drug. ## Claims ### Claim 1 A drug conjugate comprising a drug molecule covalently bonded to a thiodipeptide, the thiodipeptide having the formula wherein the drug molecule is covalently bonded to a functional group of R4, and is selected from the group consisting of an antibiotic, an anticancer drug, an antihistamine, an antihypertensive, an anti-inflammatory, an antimalarial, an antiviral, a beta blocker, a bronchodilator, a cholesterol lowering agent, a Central Nervous System (CNS) drug, a sedative, and a steroid, wherein R4 is a side chain group of serine, glutamic acid, or aspartic acid, wherein R1 is independently selected from a group consisting of: a hydrogen; and a methyl. ### Claim 2 (depends on 1) The drug conjugate of claim 1, wherein R4 comprises a spacer which is constructed and arranged to distance the drug from the thiopeptide when bound thereto. ### Claim 3 (depends on 2) The drug conjugate of claim 2, wherein the spacer comprises an alkyl chain, or an alkyl chain incorporating ether, amino, ester, amide or carbonyl groups, with a terminal group for attachment to the thiopeptide compound and the drug. ### Claim 4 (depends on 2) The drug conjugate of claim 2, wherein the spacer comprises [—CH2—]n, wherein the value of n is an integer of at least 1. ### Claim 5 (depends on 2) The drug conjugate of claim 2, wherein the spacer comprises [—CH2—O—CH2—]n, wherein n is an integer of at least one. ### Claim 6 (depends on 1) A drug conjugate according to claim 1, wherein covalent attachment of the drug molecule to the thiopeptide is by means of an ester linkage, ether linkage or an amide linkage. ### Claim 7 (depends on 1) The drug conjugate of claim 1 wherein the drug is selected from the group consisting of oxazepam, lorazepam and temazepam. ### Claim 8 (depends on 1) The drug conjugate of claim 1 wherein the N-terminal residue of the thiodipeptide is an L-isomer. ### Claim 9 (depends on 1) The drug conjugate of claim 1 wherein the C-terminal residue of the thiodipeptide is an L-isomer. ### Claim 10 (depends on 1) The drug conjugate of claim 1 wherein the N- and C-terminal residues of the thiodipeptide are L-isomers. ### Claim 11 A drug conjugate molecule, being a product of the reaction of a functional group of a thiodipeptide with a drug molecule, wherein the thiodipeptide has the formula: in which R4 comprises the functional group that reacts with the drug molecule to covalently attach the drug molecule to the thiodipeptide, wherein R4 is a side chain group of serine, glutamic acid, or aspartic acid, wherein R1 is independently selected from a group consisting of: a hydrogen; and a methyl; wherein the drug molecule is selected from the group consisting of an antibiotic, an anticancer drug, an antihistamine, an antihypertensive, an anti-inflammatory, an antimalarial, an antiviral, a beta blocker, a bronchodilator, a cholesterol lowering agent, a Central Nervous System (CNS) drug, a sedative, and a steroid.