Harnessing Multiplexed Proteolysis-Targeting Chimera for Comprehensive Influenza A Virus Targeting

Influenza A virus (IAV) remains a global health threat due to its high mutation rate and immune evasion. Current therapies, limited by single-target mechanisms and drug resistance, are insufficient. To address this, we developed a multiplexed PROTAC strategy that simultaneously targets and degrades multiple components of the viral ribonucleoprotein (vRNP) complex, the core machinery of IAV replication. Our PROTAC molecule leverages the highly conserved 5' untranslated region of viral RNA, integrating an oligonucleotide targeting ligand with an E3 ligase-recruiting unit to precisely bind and degrade vRNP components, including NP and polymerase subunits (PB1, PB2, PA). This multitarget approach disrupts viral replication at multiple levels, establishes a high genetic barrier to resistance, and demonstrates broad-spectrum activity against IAV strains. In antiviral studies, PROTAC2 exhibits exceptional potency at low concentrations (0.8 μM), sustaining inhibition for over 48 h─four times longer than ribavirin─ and shows an extended therapeutic window during late-stage infection. By simultaneously degrading eight vRNP complexes, this strategy achieves superior efficacy and virtually eliminates the risk of resistance. This innovative approach provides a durable, resistance-resistant, and highly effective therapeutic candidate, addressing the limitations of current treatments and advancing influenza therapy.