Targeted Degradation of HCV Polymerase by GalNAc-Conjugated ApTACs for Pan-Genotypic Antiviral Therapy with High Resistance Barriers.

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease. Although interferon-free direct-acting antivirals have led to significant advancements in the treatment of HCV infection, the high genetic variability of the virus and the emergence of acquired drug resistance pose potential threats to their effectiveness. In this study, we develop a broad-spectrum aptamer-based proteolysis targeting chimera, designated dNS5B, which effectively degrades both pan-genotypic NS5B polymerase and drug-resistant mutants through ubiquitin proteasome system. To achieve hepatocyte-specific uptake, we further develop Gal-dNS5B by coupling the dNS5B with a trivalent N-acetylgalactosamine (tri-GalNAc), a ligand for the liver-specific asialoglycoprotein receptor. Gal-dNS5B exclusively accumulates in hepatocytes and suppresses HCV replication by degrading NS5B. Collectively, our research lays the groundwork for a scalable strategy in the development of antiviral medications aimed at addressing current and future challenges posed by hepatitis viruses and other re-emerging viral pandemics.