ARC-520 is an RNA interference (RNAi)-based drug for the treatment of chronic hepatitis B (Hepatitis B) with the potential for a functional cure for Hepatitis B. ARC-520 intervenes at the level of messenger Ribonucleic Acid (mRNA), which is upstream of the Hepatitis B Virus reverse transcription process, and is the target of action for the standard therapeutic agents for the nucleosides and nucleoside analogs that are currently the most commonly utilized in the clinic. ACR-520 utilizes Arrowhead’s proprietary Dynamic Polyconjugates delivery system, which is based on the principle that the expression of certain proteins of the Hepatitis B virus is blocked through RNA interference, resulting in the inability of the virus to proliferate, and then the body’s immune system is utilized to remove the remaining virus, achieving an immune-cleanant state, characterized by an immune-clearant state. clearant state), characterized by hepatitis B surface antigen (HBsAg) seroconversion and with or without seroconversion. Currently, Arrowhead has completed a Phase I single-dose incremental study and is conducting a single-dose Phase IIa study and a multi-dose Phase IIb study.