Serum albumin binders

Abstract

The present invention relates to amino acid sequences binding to serum albumin. In particular, the present invention relates to improved immunoglobulin single variable domains (also referred to herein as “ISV's” or “ISVD's”), and more in particular improved heavy-chain immunoglobulin single variable domains (also referred to herein as “ISV's” or “ISVD's”) binding to serum albumin, as well as to proteins, polypeptides and other constructs, compounds, molecules or chemical entities that comprise such improved serum albumin binders.

1 .- 34 . (canceled) 
     
     
         35 . Amino acid sequence that is an immunoglobulin single variable domain capable of binding to serum albumin, in which: (i) CDR1 is GFTFSSFGMS (SEQ ID NO:120), CDR2 is SISGSGSDTL (SEQ ID NO:6) and CDR3 is GGSLSR (SEQ ID NO:7), and in which:
 the amino acid residue at Kabat position 5 is V;   the amino acid residue at Kabat position 11 is V;   the amino acid residue at Kabat position 16 is G or N;   the amino acid residue at Kabat position 45 is P or L;   the amino acid residues at Kabat positions 74 to 76 form an SKN or AKT motif;   the amino acid residue at Kabat position 89 is L, A or T; and   the amino acid residue at Kabat position 104 is G or T;   
       which amino acid sequence has no more than 7 amino acid differences with the sequence of SEQ ID NO:1, wherein the amino acid sequences of the CDRs, the amino acids at Kabat positions 5, 11, 16, 45, 74 to 76, 89 and 104, and any C-terminal extension are not taken into account in determining the number of amino acid differences. 
     
     
         36 . Amino acid sequence according to  claim 35 , in which:
 the amino acid residue at position 5 is V;   the amino acid residue at position 11 is V;   the amino acid residue at position 16 is N;   the amino acid residue at position 45 is L;   the amino acid residues at positions 74 to 76 form an AKT motif;   the amino acid residue at position 89 is L, A or T; and   the amino acid residue at position 104 is G or T.   
     
     
         37 . Protein, polypeptide or other construct, compound, molecule or chemical entity that comprises at least one amino acid sequence according to  claim 35 . 
     
     
         38 . Protein, polypeptide or other construct, compound, molecule or chemical entity according to  claim 37 , that comprises at least one therapeutic moiety or entity. 
     
     
         39 . (canceled) 
     
     
         40 . Pharmaceutical composition comprising a protein, polypeptide or other construct, compound, molecule or chemical entity according to  claim 37 . 
     
     
         41 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 16 is G. 
     
     
         42 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 16 is N. 
     
     
         43 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 45 is P. 
     
     
         44 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 45 is L. 
     
     
         45 . Amino acid sequence according to  claim 35 , in which the amino acids at Kabat positions 74 to 76 form an SKN motif. 
     
     
         46 . Amino acid sequence according to  claim 35 , in which the amino acids at Kabat positions 74 to 76 form an AKT motif. 
     
     
         47 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 89 is L. 
     
     
         48 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 89 is A. 
     
     
         49 . Amino acid sequence according to  claim 35 , in which the amino acid at Kabat position 89 is T. 
     
     
         50 . Amino acid sequence according to  claim 36 , in which the amino acid at Kabat position 89 is L. 
     
     
         51 . Amino acid sequence according to  claim 36 , in which the amino acid at Kabat position 89 is A. 
     
     
         52 . Amino acid sequence according to  claim 36 , in which the amino acid at Kabat position 89 is T. 
     
     
         53 . Nucleic acid that encodes the amino acid of  claim 35 . 
     
     
         54 . Method for preparing the amino acid sequence of  claim 35 , which method comprises cultivating or maintaining a host cell under conditions such that said host cell produces or expresses the amino acid sequence, optionally further isolating the amino acid sequence so produced.