Generally, a new targeted medicine takes a long time, usually 5 to 15 years, from the discovery and validation of its target to its actual use in treating a disease. There is no doubt that steps such as target validation and target evaluation are essential in preclinical development of new drugs to ensure safety, bioavailability, and efficacy of the drug, and in the target validation phase, RNA interference (RNAi) is a very important method. RNAi drug has double-stranded RNA function, so the targeted mRNA of a specific gene sequence is degraded, its transcription process is abnormal, which leads to gene silencing, and related protein synthesis failure. RNAi technology could specifically shut off specific genes, and, it is a targeted drug with great potential. Therefore, RNAi technology can be used to treat some rare diseases, such as acute hepatic porphyria (AHP) in adults, by using drugs as carriers. In 1998, Andrew Fire and Craig C. Mello first defined the RNAi phenomenon and was honored with the Nobel Prize in Physiology or Medicine in 2006 for their discovery of RNAi and their outstanding contributions to the field of gene silencing. Since then, RNAi drugs have been studied by pharmaceutical scientists around the world, but many of the previous drugs have been stopped at the evaluation stage due to their chemical instability. Until October 2018, the worlds first RNAi drug (patisiran) was successfully marketed so that the RNAi drug development became popular again because of remarkable pesticide effect.