EDP-721 + EDP-514

EDP-721 + EDP-514 is a combination of two investigational oral small molecule drugs developed for the treatment of chronic hepatitis B virus (HBV) infection. **EDP-721** is a selective inhibitor of the host non-canonical poly(A) RNA polymerases PAPD5 and PAPD7, which are key to the post-transcriptional stabilization of HBV RNA; inhibition of these enzymes destabilizes viral transcripts and markedly reduces production of viral proteins such as HBsAg[1][5]. **EDP-514** is a potent type II core protein inhibitor that targets the HBV core protein to disrupt viral replication, assembly, and formation of new virions[2][3]. Preclinical studies demonstrated additive to synergistic antiviral effects of the combination, but development of EDP-721 was terminated after safety issues in a phase 1 trial[7]; EDP-514 continues development as a monotherapy. The combination aimed to achieve a functional HBV cure via two distinct antiviral mechanisms.