Tetragalnac containing conjugates and methods for delivery of oligonucleotides

#Scientific efforts focused on the delivery of oligonucleotides systemically for therapeutic purposes are ongoing. Three highlighted approaches to oligonucleotide delivery include 1) lipid nanoparticle (LNP) encapsulation, 2) polymer conjugation and 3) single chemical conjugation. Single chemical conjugation typically employs a targeting ligand or a lipid or a solubilizing group or an endosomolytic peptide or a cell penetrating peptide and/or a combination of two or all four attached to an oligonucleotide. Linkers may be present in the conjugate as well as other functionalities. Single chemical conjugates are known and attachment of the oligonucleotide occurs either at the 5′- or 3′-end of the oligonucleotide, at both ends, or internally. See WO2005/041859, WO2008/036825, and WO2009/126933.

#Considerable amount of literature evidence supports the hypothesis that the major hurdles for oligonucleotide delivery are cell uptake and endosomal escape. There remains a need for additional single chemical conjugates that can provide effective delivery efficiency, cell uptake and/or endosomal escape.

#Single chemical conjugates comprising tetraGalNAc ligands disclosed herein have surprising properties of improved delivery efficiency, cell uptake and/or endosomal escape.

#Disclosed herein are single chemical conjugates comprising a single stranded or double stranded oligonucleotide; and one or more tetraGalNAc ligands of Formula (I), which may be the same or different:

#wherein X is —O—, —S—, —CR1R2— or —NR1—, wherein R1 and R2 are each independently selected from the group consisting of hydrogen and C1-C6alkyl; n is 1, 2, 3, or 4; and the bond with “” indicates the point of attachment. Other functionalities, such as targeting ligands, solubilizing agents, pharmacokinetics enhancing agents, lipids, and/or masking agents are optionally present. In one embodiment, R1 and R2 are each independently selected from the group consisting of hydrogen, methyl and ethyl. In another embodiment, R1 and R2 are each hydrogen.

#In one embodiment, the tetraGalNAc ligand has Formula (II) wherein X, R1, R2 and n are as defined above. In another embodiment, the tetraGalNAc ligand has Formula (III) wherein X, R1, R2 and n are as defined above: