Hemagglutinin docking analysis-based visual detection of antiviral therapeutic efficacy of umifenovir against influenza virus.

The rapid evolution of viruses poses a significant threat to global health, as evidenced by recent pandemics. Umifenovir (Arbidol®), a broad-spectrum antiviral drug, has demonstrated potential in treating various viral infections. This study aimed to assess the antiviral mechanism of umifenovir against influenza A virus (IAV), specifically its interaction with hemagglutinin (HA), using umifenovir-modified gold nanoparticles (umi-GNPs). Umi-GNPs have been applied to various IAV subtypes, including H1N1, H3N2, H4N6, H6N8, and H9N2. Our results demonstrate that umifenovir effectively inhibits viral replication in all tested subtypes at a viral titer of 104.5 50 % egg infective dose (EID50)/mL. Additionally, the aggregation of umi-GNPs with viruses pre-bound to umifenovir was suppressed, indicating that umi-GNPs bind to a specific region of the viral protein. These findings indicate that umi-GNPs can serve as novel agents for visually determining umifenovir resistance in IAV.