Fig. 3.

Medical applications of RNA drugs and FDA approved RNAi drugs. A The applications of mRNA-based drugs for disease therapy include vaccines, cell therapy, therapeutic protein production, and protein replacement. mRNA-based drugs have proven to be a potent competitor in vaccine development. Along with prevention of infectious diseases, mRNA vaccines may also be used in the treatment of cancer. Regarding cell therapies, mRNAs can be applied in CAR-T cell therapy, or treatments may also be developed to target disease-relevant cell types, such as cardiac cells, blood cells, hepatocytes and neurons. For therapeutic protein production, mRNAs can be translated into patient’s own cells to produce therapeutically active proteins. These protein-encoding mRNAs can be used for antigen presentation, functional protein expression, or Cas9 protein expression for target gene modification. Furthermore, small RNAs (e.g., siRNA or miRNA) may be useful to inhibit overactive genes. For protein replacement, protein-coding mRNAs can be used as gain-of-function therapies, replacing non-functional mutant proteins to restore normal physiological function. B The table shows U.S. FDA-approved RNAi drugs currently in clinical use