RNA therapeutics for metabolic disorders.

The prevalence of metabolic disorders is increasing exponentially and has recently reached epidemic levels. Over the decades, a large number of therapeutic options have been proposed to manage these diseases but still show several limitations. In this circumstance, RNA therapeutics have rapidly emerged as a new hope for patients with metabolic diseases. 57 years have elapsed from the discovery of mRNA, a large number of RNA-based drug candidates have been evaluated for their therapeutic effectiveness and clinical safety under clinical studies. To date, there are seven RNA drugs for treating metabolic disorders receiving official approval and entering the global market. Their targets include hereditary transthyretin-mediated amyloidosis (hATTR), familial chylomicronemia syndrome, acute hepatic porphyria, primary hyperoxaluria type 1 and hypercholesterolemia, which are all related to liver proteins. All of these seven RNA drugs are antisense oligonucleotides (ASO) and small interfering RNA (siRNA). These two types of treatment are both based on oligonucleotides complementary to target RNA through Watson-Crick base-pairing, but their mechanisms of action include different nucleases. Such treatments show greatest potential among all types of RNA therapeutics due to consecutive achievements in chemical modifications. Another method, mRNA therapeutics also promise a brighter future for patients with a handful of drug candidates currently under development.