HAA-09, an orally administered compound, serves as a powerful anti-influenza agent by targeting the influenza PB2_cap binding domain. It possesses significant activity against influenza A virus, exhibiting an EC50 of 0.03 μM, and demonstrates polymerase inhibition with an IC50 of 0.06±0.004 μM. Importantly, HAA-09 inhibits virus replication efficiently without inducing noticeable cytotoxicity [1].