Intestinal peptide targeting ligands

Abstract

Peptide ligands for transporting therapeutic agents across the intestinal epithelial barrier that ordinarily are inadequately absorbed and must be delivered by alternative means, which contain an isolated amino acid sequence wherein at least one pair of amino acids are of an opposite charge and the pair members are separated by a spacer of 1-12 amino acid residues including at least one hydrophobic amino acid, and wherein the length of the amino acid sequence is greater than 5 and less than 20 amino acids. Pharmaceutical compositions for gastro-intestinal delivery and methods for the gastrointestinal delivery of poorly absorbed therapeutic agents are also disclosed.

1 . A peptide ligand comprising an isolated amino acid sequence wherein at least one pair of amino acids are of an opposite charge, wherein the members of said pair are separated by a spacer consisting of 1-12 amino acid residues and comprising at least one hydrophobic amino acid, and wherein the length of said amino acid sequence is greater than 5 and less than 20 amino acids. 
     
     
         2 . The isolated amino acid sequence of  claim 1 , wherein the first member of said pair is selected from the group consisting of D and E, and the second member is independently selected from the group consisting of K, R, and H. 
     
     
         3 . The isolated amino acid sequence according to  claim 1  or  2 , comprising two pairs of amino acids of opposite polarity. 
     
     
         4 . The isolated amino acid sequence according to any one of  claims 1 - 3 , comprising Formula 1:
   X 1 B 1 Z 1 Z 2 Z 3 B 2 ,   
       wherein X 1  is not a charged or hydrophobic amino acid, Z 1 -Z 3  is a spacer sequence of at least one hydrophobic amino acid, and B 1  and B 2  are members of said at least one pair and have opposite charge. 
     
     
         5 . The isolated amino acid sequence according to any one of  claims 1 - 4 , comprising Formula 2:
   X 1 B 1 Z 1 Z 2 Z 3 B 2 X 2 X 3 X 4 ,   
       wherein X 1 -X 4  are not charged or hydrophobic amino acids, Z 1 -Z 3  is a spacer sequence of at least one hydrophobic amino acid, and B 1  and B 2  are members of said at least one pair and have opposite charge. 
     
     
         6 . The isolated amino acid sequence according to any one of  claims 1 - 5 , comprising Formula 3:
   X 1 B 1 Z 1 Z 2 Z 3 B 2 X 2 X 3 X 4 X 5 X 6 X 7 ,   
       wherein X 1 -X 7  are not charged or hydrophobic amino acids, Z 1 -Z 3  is a spacer sequence of at least one hydrophobic amino acid, and B 1  and B 2  are members of said at least one pair and have opposite charge. 
     
     
         5 . The isolated amino acid sequence of  claim 4 , which is at least 75% identical to SEQ ID NO: 4, and wherein further, non-identical amino acids are conservative substitutions of corresponding residues of SEQ ID NO: 4. 
     
     
         6 . The isolated amino acid sequence of  claim 5 , which is at least 75% identical to SEQ ID NO: 5, and wherein further, non-identical amino acids are conservative substitutions of corresponding residues of SEQ ID NO: 5. 
     
     
         7 . The isolated amino acid sequence of  claim 6 , which is at least 75% identical to SEQ ID NO: 1 (original sequence), and wherein further, non-identical amino acids are conservative substitutions of corresponding residues of SEQ ID NO: 5. 
     
     
         8 . The isolated amino acid sequence according to any one of  claims 1 - 7 , which comprises SEQ ID NO: 4; or consists essentially of SEQ ID NO: 4; or consists of SEQ ID NO: 4. 
     
     
         9 . The amino acid sequence of any one of  claims 1 - 3 , comprising Formula 4:
   X 1 B 1 B 2 Z 1 Z 2 Z 3 Z 4 Z 5 B 3 Z 6 Z 7 B 4 ,   
       wherein X 1  is either an uncharged amino acid or hydrophobic amino acid, Z 1 -Z 7  is a spacer sequence of at least one hydrophobic amino acid, and B 1 -B 4  are charged amino acids and wherein B 1  and B 2  have an identical charge which charge is opposite to the charge of B 3  and B 4 . 
     
     
         10 . The amino acid sequence of  claim 7 , which is at least 75% identical to SEQ ID NO: 2 (Peptide 12), and wherein further, non-identical amino acids are conservative substitutions of corresponding residues of SEQ ID NO: 2. 
     
     
         11 . The amino acid sequence according to any one of  claim 1 - 3 ,  9  or  10  which comprises SEQ ID NO: 2; or consists essentially of SEQ ID NO: 2; or consists of SEQ ID NO: 2. 
     
     
         12 . The amino acid sequence according to any one of  claims 1 - 3 , comprising Formula 5:
   X 1 B 1 Z 1 Z 2 B 2 Z 3 B 3 Z 4 B 4 Z 5 Z 6 B 5 Z 7 B 6 X 2 X 3 X 4 ,   
       wherein X 1 -X 4  are not charged or hydrophobic amino acids, Z 1 -Z 7  is a spacer sequence of at least one hydrophobic amino acid, and B 1 -B 6  are charged amino acids and wherein B 1 , B 2  and B 3  have an identical charge that is opposite to the charge of B 4 , B 5  and B 6 . 
     
     
         13 . The amino acid sequence of  claim 12 , which is at least 75% identical to SEQ ID NO: 3, and wherein further, non-identical amino acids are conservative substitutions of corresponding residues of SEQ ID NO: 3. 
     
     
         14 . The amino acid sequence according to any one of  claim 1 - 3 ,  12  or  13  which comprises SEQ ID NO: 3; or consists essentially of SEQ ID NO: 3; or consists of SEQ ID NO: 3. 
     
     
         15 . A composition comprising the amino acid sequence of  claim 1  and a therapeutic agent or a pharmaceutically acceptable carrier. 
     
     
         16 . The composition of  claim 15  wherein the amino acid sequence of  claim 1  is bound to said agent or said carrier. 
     
     
         17 . A composition comprising the amino acid sequence of  claim 15 , a therapeutic agent and a pharmaceutically acceptable carrier. 
     
     
         18 . The composition of  claim 17  wherein the amino acid sequence of  claim 1  is bound to said agent or said carrier. 
     
     
         19 . The composition according to  claim 15  wherein the therapeutic agent is a pharmaceutically active, diagnostic, biologic, imaging or targeting agent. 
     
     
         20 . The composition according to  claim 15 , wherein said therapeutic agent has poor gastrointestinal absorption. 
     
     
         21 . The composition according to  claim 15  wherein said carrier is a nanoparticle or a microparticle. 
     
     
         22 . The composition according to  claim 15 , wherein said carrier comprises a polymer. 
     
     
         23 . The composition according to  claim 15 , wherein said carrier is equal to or greater than 50 nm in diameter. 
     
     
         24 . The composition of  claim 22  wherein the polymer is polyethylene glycol. 
     
     
         25 . A method for the gastrointestinal delivery of a therapeutic agent with poor gastrointestinal absorption to a patient in need thereof, comprising administering to said patient a composition according to  claim 15  by a gastrointestinal route of administration. 
     
     
         26 . The method of  claim 25 , wherein said gastrointestinal route of administration is an oral route of administration. 
     
     
         27 . Use of the composition of  claim 1  for the administration of a therapeutic agent with poor gastrointestinal absorption. 
     
     
         28 . Use of the composition of  claim 1  for the manufacture of a medicament for the delivery of a therapeutic agent with poor gastrointestinal absorption.