GalNAc

N-acetylgalactosamine (GalNAc) is a ligand widely used for hepatocyte-targeted delivery of oligonucleotide therapeutics. GalNAc conjugates typically employ a triantennary structure that binds with high affinity to the asialoglycoprotein receptor (ASGPR) expressed on hepatocytes. After receptor recognition, the conjugate is internalized through receptor-mediated endocytosis, allowing efficient uptake of siRNA or antisense oligonucleotides by liver cells. This targeted delivery strategy significantly enhances intracellular exposure while reducing systemic distribution.