The potency of antisense oligonucleotide (ASO) drugs has significantly improved in the clinic after exploiting asialoglycoprotein receptor (ASGR) mediated delivery to hepatocytes. To further this technology, we evaluated the structure–activity relationships of oligonucleotide chemistry on in vivo potency of GalNAc-conjugated Gapmer ASOs. GalNAc conjugation improved potency of ASOs containing 2′-O-methyl (2′-O-Me), 3′-fluoro hexitol nucleic acid (FHNA), locked nucleic acid (LNA), and constrained ethyl bicyclo nucleic acid (cEt BNA) 10–20-fold compared to unconjugated ASOs. We further demonstrate that GalNAc conjugation improves activity of 2′-O-(2-methoxyethyl) (2′-O-MOE) and Morpholino ASOs designed to correct splicing of survival motor neuron (SMN2) pre-mRNA in liver after subcutaneous administration. GalNAc modification thus represents a viable strategy for enhancing potency of ASO with diverse nucleic acid modifications and mechanisms of action for targets expressed in hepatocytes.

利用去唾液酸糖蛋白受体（ASGR）介导的肝细胞递送后，反义寡核苷酸（ASO）药物的功效在临床上已得到显着改善。为了进一步推广这项技术，我们评估了寡核苷酸化学结构与GalNAc偶联的Gapmer ASO的体内效能之间的构效关系。GalNAc偶联提高了包含2'- O-甲基（2'- O -Me），3'-氟己糖醇核酸（FHNA），锁核酸（LNA）和约束乙基双环核酸（cEt BNA）的ASO的效能与未结合的ASO相比，是10到20倍。我们进一步证明GalNAc共轭可提高2' - O-（2-甲氧基乙基）（2'- O-MOE）和Morpholino ASO，旨在纠正皮下给药后肝脏中的存活运动神经元（SMN2）pre-mRNA的剪接。因此，GalNAc修饰代表了一种可行的策略，可通过多种核酸修饰和针对肝细胞中表达的靶标的作用机制来增强ASO的效力。