Cholesterol-GalNAc Dual Conjugation Strategy for Reducing Renal Distribution of Antisense Oligonucleotides

Recently, some studies have reported nephrotoxicity associated with a certain class of antisense oligonucleotides (ASOs) in humans. One possibility for reducing the potential nephrotoxicity of ASOs is to alter their pharmacokinetics. In this study, we investigated the effect of a ligand conjugation strategy on the renal accumulation of ASOs. We selected two ligands, cholesterol and N-acetylgalactosamine (GalNAc), with the purpose of reducing renal distribution and liver targeting, and then designed a series of cholesterol-GalNAc dual conjugated ASOs. The gene-silencing activity of the cholesterol-GalNAc dual conjugated ASO in the liver was slightly lower than that of a GalNAc-conjugated ASO. On the other hand, the renal distribution of the cholesterol-GalNAc dual conjugated ASO was considerably decreased compared with the GalNAc-conjugated ASO, as we expected. As dual conjugation was successful in reducing the renal distribution of ASO, it should be an effective strategy for reducing the nephrotoxic potential of ASOs.