Oligonucleotide analogues with locked-amide linkages have therapeutic potential

Ysobel Baker, Cameron Thorpe, Jinfeng Chen, Laura Poller, Lina Cox, Pawan Kumar, Wooi Fang Lim, Lillian Lie, Graham McClorey, Sven Epple, Daniel Singleton, Michael McDonough, Jack Hardwick, Kirsten Christensen, Matthew Wood, James Hall, Afaf El-Sagheer, Tom Brown. Research Square 0, 0, 2022.

Abstract

Oligonucleotides that target mRNA have great promise as therapeutic agents for life-threatening conditions but suffer from poor bioavailability, hence high cost. As currently untreatable diseases come within the reach of oligonucleotide therapies, new analogues are urgently needed to address this. With this in mind we have developed reduced-charge oligonucleotides containing arti cial LNA-amide linkages with improved gymnotic cell uptake, RNA a nity, stability and potency. To construct such oligonucleotides, ve LNA-amide monomers (A, T, C, 5mC and G), where the 3-OH is replaced by an ethanoic acid group, were synthesised in good yield and used in solid-phase oligonucleotide synthesis to form amide linkages with high e ciency. The arti cial backbone causes minimal structural deviation to the DNA: RNA duplex. These studies indicate that splice-switching oligonucleotides containing LNA-amide linkages and phosphorothioates display improved activity relative to oligonucleotides lacking amides, highlighting the therapeutic potential of this technology.