Compositions and methods for enhancing drug delivery across and into epithelial tissues

Abstract

This invention provides compositions and methods for enhancing delivery of drugs and other agents across epithelial tissues, including the skin, gastrointestinal tract, pulmonary epithelium, ocular tissues and the like. The compositions and methods are also useful for delivery across endothelial tissues, including the blood brain barrier. The compositions and methods employ a delivery enhancing transporter that has sufficient guanidino or amidino sidechain moieties to enhance delivery of a compound conjugated to the reagent across one or more layers of the tissue, compared to the non-conjugated compound. The delivery-enhancing polymers include, for example, poly-arginine molecules that are preferably between about 6 and 25 residues in length.

1 . A method of: 
 (a) targeting a compound to a gastrointestinal epithelium of an animal, the method comprising administering to the gastrointestinal epithelium a conjugate comprising the compound and a delivery-enhancing transporter, or    (b) enhancing delivery of a compound into and across one or more layers of an animal ocular epithelial tissue, the method comprising administering to the ocular epithelial tissue a conjugate comprising the compound and a delivery-enhancing transporter,    wherein:    i. the compound is attached to the delivery-enhancing transporter through a linker; and    ii. the delivery-enhancing transporter comprises fewer than 50 subunits and comprises at least 5 guanidino or amidino moieties, thereby increasing delivery of the conjugate into the gastrointestinal epithelium compared to delivery of the compound in the absence of the delivery-enhancing transporter.    
     
     
         2 . The method of  claim 1 , wherein delivery of the conjugate into the gastrointestinal epithelium for method (a) or delivery of the conjugate across one or more layers of ocular epithelial tissue for method (b) is increased at least two-fold compared to delivery of the compound in the absence of the delivery-enhancing transporter.  
     
     
         3 . The method of  claim 1 , wherein delivery of the conjugate into the gastrointestinal epithelium for method (a) or delivery of the conjugate across one or more layers of ocular epithelial tissue for method (b) is increased at least ten-fold compared to delivery of the compound in the absence of the delivery-enhancing transporter.  
     
     
         4 . The method of  claim 1 , wherein the linker is a releasable linker.  
     
     
         5 . The method of  claim 1 , wherein the subunits are amino acids.  
     
     
         6 . The method of  claim 1 , wherein the conjugate has a structure selected from the group consisting of structures 3, 4, and 5, as follows:  
       
         
           
           
               
               
           
         
         wherein:  
         R1 comprises the compound;  
         X is a linkage formed between a functional group on the biologically active compound and a terminal functional group on the linking moiety;  
         Y is a linkage formed from a functional group on the transport moiety and a functional group on the linking moiety;  
         A is N or CH;  
         R2 is hydrogen, alkyl, aryl, acyl, or allyl;  
         R3 comprises the delivery-enhancing transporter;  
         R4 is S, O, NR6 or CR7R8;  
         R5 is H, OH, SH or NHR6;  
         R6 is hydrogen, alkyl, aryl, acyl or allyl;  
         k and m are each independently selected from 1 and 2; and  
         n is 1 to 10.  
       
     
     
         7 . The method of  claim 6 , wherein X is selected from the group consisting of —C(O)O—, —C(O)NH—, —OC(O)NH—, —S—S—, —C(S)O—, —C(S)NH—, —NHC(O)NH—, —SO2NH—, —SONH—, phosphate, phosphonate phosphinate, and CR7R8, wherein R7 and R8 are each independently selected from the group consisting of H and alkyl.  
     
     
         8 . The method of  claim 6 , wherein the conjugate comprises structure 3, Y is N, and R2 is methyl, ethyl, propyl, butyl, allyl, benzyl or phenyl.  
     
     
         9 . The method of  claim 6 , wherein R2 is benzyl; k, m, and n are each 1, and X is —OC(O)—.  
     
     
         10 . The method of  claim 6 , wherein the conjugate comprises structure 4; R4 is S; R5 is NHR 6 ; and R6 is hydrogen, methyl, allyl, butyl or phenyl.  
     
     
         11 . The method of  claim 6 , wherein the conjugate comprises structure 4; R5 is NHR6; R6 is hydrogen, methyl, allyl, butyl or phenyl; and k and m are each 1.  
     
     
         12 . The method of  claim 1 , wherein the conjugate comprises structure 6 as follows:  
       
         
           
           
               
               
           
         
         wherein:  
         R1 comprises the compound;  
         X is a linkage formed between a functional group on the biologically active compound and a terminal functional group on the linking moiety;  
         Y is a linkage formed from a functional group on the transport moiety and a functional group on the linking moiety;  
         Ar is an aryl group having the attached radicals arranged in an ortho or para configuration, which aryl group can be substituted or unsubstituted;  
         R3 comprises the delivery-enhancing transporter;  
         R4 is S, O, NR6 or CR7R8;  
         R5 is H, OH, SH or NHR6;  
         R6 is hydrogen, alkyl, aryl, arylalkyl, acyl or allyl;  
         R7 and R8 are independently selected from hydrogen or alkyl; and  
         k and m are each independently selected from 1 and 2.  
       
     
     
         13 . The method of  claim 12 , wherein X is selected from the group consisting of —C(O)O—, —C(O)NH—, —OC(O)NH—, —S—S—, —C(S)O—, —C(S)NH—, —NHC(O)NH—, —SO2NH—, —SONH—, phosphate, phosphonate phosphinate, and CR7R8, wherein R7 and R8 are each independently selected from the group consisting of H and alkyl.  
     
     
         14 . The method of  claim 12 , wherein R4 is S; R5 is NHR6; and R6 is hydrogen, methyl, allyl, butyl or phenyl.  
     
     
         15 . The method of  claim 1 , wherein the conjugate comprises at least two delivery-enhancing transporters.  
     
     
         16 . The method of  claim 1 , wherein the conjugate is administered buccally if the method of  claim 1  is method (a) or wherein the conjugate is administered as an eye drop if the method of  claim 1  is method (b).  
     
     
         17 . The method of  claim 1 , wherein the conjugate is administered as a suppository if the method of  claim 1  is method (a) or wherein the conjugate is administered as an injection if the method of  claim 1  is method (b).  
     
     
         18 . The method of  claim 1 , wherein the delivery-enhancing transporter comprises a non-peptide backbone.  
     
     
         19 . The method of  claim 1 , wherein the delivery-enhancing transporter is not attached to an amino acid sequence to which the delivery enhancing transporter molecule is attached in a naturally occurring protein.  
     
     
         20 . The method of  claim 1 , wherein the delivery-enhancing transporter comprises from 5 to 25 guanidino or amidino moieties.  
     
     
         21 . The method of  claim 20 , wherein the delivery-enhancing transporter comprises between 7 and 15 guanidino moieties.  
     
     
         22 . The method of  claim 20 , wherein the delivery-enhancing transporter comprises at least 6 contiguous guanidino and/or amidino moieties.  
     
     
         23 . The method of  claim 1 , wherein the delivery-enhancing transporter consists essentially of 5 to 50 amino acids, at least 50 percent of which amino acids are arginines or analogs thereof.  
     
     
         24 . The method of  claim 23 , wherein the delivery-enhancing transporter comprises 5 to 25 arginine residues or analogs thereof.  
     
     
         25 . The method of  claim 24 , wherein at least one arginine is a D-arginine.  
     
     
         26 . The method of  claim 25 , wherein all of the arginines are D-arginines.  
     
     
         27 . The method of  claim 23 , wherein at least 70 percent of the amino acids that comprise the delivery-enhancing transporter are arginines or arginine analogs.  
     
     
         28 . The method of  claim 23 , wherein the delivery-enhancing transporter is seven contiguous D-arginines.  
     
     
         29 . The method of  claim 1 , wherein the compound is a therapeutic for the disease selected from the group consisting of inflammatory bowel disease, colon cancer, ulcerative colitis, gastrointestinal ulcers, constipation and imbalance of salt and water absorption when the method of  claim 1  is method (a); or 
 wherein the compound is a therapeutic for the disease selected from the group consisting of conjunctivitis, bacterial infections, viral infections, dry eye and glaucoma when the method of  claim 1  is method (b).    
     
     
         30 . The method of  claim 1 , wherein the compound is selected from the group consisting of immunosuppressives, ascomycins, corticosteroids, laxatives, antibiotics and anti-neoplastic agents when the method of  claim 1  is method (a); or 
 wherein the compound is selected from the group consisting of antibacterial compounds, antiviral compounds, cyclosporine, ascomycins, and corticosteroids when the method of  claim 1  is method (b).    
     
     
         31 . The method of  claim 1 , wherein the method of  claim 1  is method (a) and the compound is targeted to the iliem and/or colon.