Pharmaceutical perspectives on oligonucleotide therapeutics and delivery systems

Gene therapy has a pivotal role in treating new diseases. In addition to the recent mRNA-based COVID-19 vaccines produced by Pfizer-BioNTech and Moderna against severe acute respiratory syndrome corona virus 2, several new gene therapies have recently been approved as effective treatments for fatal genetic disorders such as Duchenne's muscular dystrophy, familial transthyretin amyloidosis, hemophilia A, hemophilia B, spinal muscle atrophy, early cerebral autoleukodystrophy, and β-thalassemia. This review provides novel insights into RNA therapeutics focusing on endogenous RNA species, RNA structure and function, and chemical modifications that improve the stability and distribution of RNAs. Furthermore, it includes updated knowledge on clinically approved gene therapies rendering a comprehensive understanding of the biochemical basis and clinical application of gene therapies. SIGNIFICANCE STATEMENT: There have recently been significant advances in clinical translation of RNA therapeutics. This review discusses the diverse types of RNA species, RNA structure and function, backbone and chemical modifications to RNAs, and every RNA therapeutic approved for clinical use at the time of writing.