# US 2014/0154241 A1 · Binding peptides i > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154241 A1 - Document ID: US20140154241A1 - Status: Published application - Kind: A1 - Application number: 13/991,178 - Filed: 2011-12-05 - Published: 2014-06-05 - Earliest claimed: 2010-12-03 - Assignees: Cyclogenix Ltd - Inventors: Duncan McGregor; William Eldridge; Simon Robins; Marie Fernie; Tricia White; Stuart Pritchard; Susan King - Web page: https://patentgrep.com/patent/US20140154241A1 ## CPC - C07K 16/18: against material from animals or humans - C07K 14/461: {from fish} - C07K 2317/20: characterized by taxonomic origin - C07K 2317/565: Complementarity determining region [CDR] - C07K 2319/31: fusions, other than Fc, for prolonged plasma life, e.g. albumin - 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) ## Abstract A modified igNAR peptide sequence derived from a wild-type igNAR peptide sequence is diversified by mutating the amino acid sequence at 50% or more of the amino acids in the CDR3 loop region and optionally at 50% or more of the amino acids in the CDR3 loop region. The modified igNAR peptide may have the sequence of SEQ ID NO: 8, 10 or 50 to 85. The modified igNAR peptides have binding activity against albumin protein sequences, such as human serum albumin. These modified igNAR peptides may have utility in extending the in vivo half-life of biological molecules e.g. therapeutic agents, and so may be used in medicine. ## Claims ### Claim 1 A modified immunoglobulin New Antigen Receptor (igNAR) peptide sequence derived from a wild-type igNAR peptide sequence, which is diversified by mutating the amino acid sequence at 50% or more of the amino acids in the CDR3 loop region, wherein the modified igNAR peptide sequence demonstrates a binding affinity for a target peptide sequence. ### Claim 2 (depends on 1) The modified igNAR peptide of claim 1, which is further diversified by mutating the amino acid sequence at 50% or more of the amino acids in the CDR1 loop region. ### Claim 3 (depends on 1) The modified igNAR peptide of claim 1, which is derived from the variable domain of the Wobbegong shark igNAR peptide (SEQ ID NO: 86). ### Claim 4 (depends on 1) The modified igNAR peptide of claim 1, wherein the modified igNAR peptide sequence contains diversifications at 50% or more of the residues selected from one or more of the group consisting of: SEQ ID NO: 87 and SEQ ID NO: 11. ### Claim 5 (depends on 1) The modified igNAR peptide of claim 1, which comprises a sequence having at least 90% identity in the region of amino acid positions 1 to 84 and 101 to 110 to a sequence selected from one or more of the group consisting of: SEQ ID NO: 8; SEQ ID NO: 10; and SEQ ID NO: 86. ### Claim 6 (depends on 1) The modified igNAR peptide of claim 1, which comprises a sequence having at least 95% identity to SEQ ID NO: 86 in the region of positions 1 to 18, 26 to 84 and 98 to 107. ### Claim 7 (depends on 1) The modified igNAR peptide of claim 1, wherein the CDR3 loop has at least 11 amino acids residues. ### Claim 8 (depends on 1) The modified igNAR peptide of claim 1, wherein the CDR3 loop has 16 amino acids and does not include a cysteine at position 88 of SEQ ID NO: 86. ### Claim 9 (canceled) ### Claim 10 (depends on 1) The modified igNAR peptide of claim 1, which comprises: (i) the modified CDR3 sequence of SEQ ID NO: 9; and (ii) a modified CDR1 sequence selected from one or more of the group consisting of: SEQ ID NOs: 16 to 50. ### Claim 11 (depends on 1) A modified igNAR peptide which comprises at least 70 consecutive amino acids of the peptide of claim 1. ### Claim 12 (depends on 1) The modified igNAR peptide sequence of claim 1, which comprises an amino acid sequence selected from any of the group consisting of SEQ ID NO: 8; 10; 51 to 85; and a sequence having at least 98% identity thereto over a length of at least 100 amino acids. ### Claim 13 (depends on 1) The modified igNAR peptide sequence of claim 1, wherein the target peptide comprises an albumin peptide sequence. ### Claim 14 (depends on 13) The modified igNAR peptide sequence of claim 13, wherein the albumin peptide sequence comprises one of the group selected from: a human; mouse; and rat albumin protein. ### Claim 15 (depends on 13) The modified igNAR peptide sequence of claim 13, which binds the albumin peptide sequence with a dissociation constant (Kd) of less than 10 μM. ### Claim at position 16 -27. (canceled) ### Claim 28 (depends on 1) A method of treating, preventing or alleviating a disease in a mammal, the method comprising administering to a subject in need thereof a therapeutically effective amount of the modified igNAR peptide of claim 1. ### Claim 29 (depends on 1) A pharmaceutical composition comprising the peptide of claim 1. ### Claim 30 A method of extending the in vivo or serum half-life of a therapeutic molecule by conjugating or associating the therapeutic molecule with a modified igNAR peptide sequence capable of binding to an albumin. ### Claim 31 (depends on 30) The method of claim 30, wherein the igNAR peptide sequence comprises a peptide sequence derived from a wild-type igNAR peptide sequence, which is diversified by mutating the amino acid sequence at 50% or more of the amino acids in the CDR3 loop region, wherein the modified igNAR peptide sequence demonstrates a binding affinity for a target peptide sequence. ### Claim 32 (canceled) ### Claim 33 (depends on 30) The method of claim 30, wherein the albumin is a human serum albumin.