Polyconjugates for Delivery of RNAi triggers to Tumor Cells In Vivo

Abstract

The present invention is directed compositions for delivery of RNA interference (RNAi) triggers to integrin positive tumor cells in vivo. The compositions comprise RGD ligand-targeted amphipathic membrane active polyamines reversibly modified with enzyme cleavable dipeptide-amidobenzyl-carbonate masking agents. Modification masks membrane activity of the polymer while reversibility provides physiological responsiveness. The reversibly modified polyamines (dynamic polyconjugate or conjugate) are further covalently linked to an RNAi trigger.

We claim: 
     
         1 . An RGD ligand-containing moiety comprising the structure represented by: 
       
         
           
           
               
               
           
         
         wherein:
 R 14  is 
 
       
       
         
           
           
               
               
           
         
          and
 A comprises a linker, 
 wherein the RGD ligand-containing moiety is bound to a carbamate-containing moiety and an RNAi trigger. 
 
       
     
     
         2 . The RGD ligand-containing moiety of  claim 1 , wherein A comprises: 
       
         
           
           
               
               
           
         
         wherein 
         n is 0, 1, 2, or 3, 
         Y is absent or 
       
       
         
           
           
               
               
           
         
         Z is absent, 
       
       
         
           
           
               
               
           
         
         m is 0, 1, 2, 3, or 4, and 
         PEG is (CH 2 —CH 2 —O) 4-44 . 
       
     
     
         3 . The RGD ligand-containing moiety of  claim 1 , wherein R 14  is 
       
         
           
           
               
               
           
         
       
     
     
         4 . The RGD ligand-containing moiety of  claim 1 , wherein the RGD ligand-containing moiety is of the structure: 
       
         
           
           
               
               
           
         
         wherein
 A′ comprises a PEG-containing linker; 
 R 1  is a side group of an alanine, phenylalanine, valine, leucine, isoleucine, and tryptophan; 
 R 2  is a side chain of a citrulline, glycine, threonine, asparagine, and glutamine; and 
 the RGD ligand is bound to an RNAi trigger. 
 
       
     
     
         5 . The RGD ligand of  claim 4 , wherein R 1  is the side group of alanine. 
     
     
         6 . The RGD ligand of  claim 4 , wherein R 1  is the side group of phenylalanine. 
     
     
         7 . The RGD ligand of  claim 4 , wherein R 1  is the side group of leucine. 
     
     
         8 . The RGD ligand of  claim 4 , wherein R 1  is the side group of isoleucine. 
     
     
         9 . The RGD ligand of  claim 4 , wherein R 1  is the side group of tryptophan. 
     
     
         10 . The RGD ligand of  claim 4 , wherein R 2  is the side group of citrulline. 
     
     
         11 . The RGD ligand of  claim 4 , wherein R 2  is the side group of glycine. 
     
     
         12 . The RGD ligand of  claim 4 , wherein R 2  is the side group of threonine. 
     
     
         13 . The RGD ligand of  claim 4 , wherein R 2  is the side group of asparagine. 
     
     
         14 . The RGD ligand of  claim 4 , wherein R 2  is the side group of glutamine. 
     
     
         15 . A masking agent of the formula:
   (R)-A 1 A 2 -amidobenzyl-carbonate,   wherein,   R is of the formula:   
       
         
           
           
               
               
           
         
         R 14  is 
       
       
         
           
           
               
               
           
         
       
       and
 A comprises a linker; 
 A 1  is selected from alanine, phenylalanine, valine, leucine, isoleucine, and tryptophan; and 
 A 2  is selected from citrulline, glycine, threonine, asparagine, and glutamine. 
 
     
     
         16 . The masking agent of  claim 15 , wherein R 2  is citrulline. 
     
     
         17 . The masking agent of  claim 15 , wherein R 14  is 
       
         
           
           
               
               
           
         
       
     
     
         18 . The masking agent of  claim 15 , wherein A comprises: 
       
         
           
           
               
               
           
         
         wherein 
         n is 0, 1, 2, or 3, 
         Y is absent or 
       
       
         
           
           
               
               
           
         
         Z is absent, 
       
       
         
           
           
               
               
           
         
         m is 0, 1, 2, 3, or 4, and 
         PEG is (CH 2 —CH 2 —O) 4-44 . 
       
     
     
         19 . The masking agent of  claim 18 , wherein n is 3. 
     
     
         20 . The masking agent of  claim 18 , wherein Y is 
       
         
           
           
               
               
           
         
       
       and Z is