AM-001, a small-molecule EPAC1 (exchange protein directly activated by cAMP) inhibitor, showed potent in vitro antiviral activity against SARS-CoV-2 and influenza A in cultured cells. In Vero E6 cells, AM-001 reduced SARS-CoV-2 viral RNA and infectious titres with IC₅₀ ≈ 355–388 nM and in human lung Calu-3 cells with IC₅₀ ≈ 147–167 nM, achieving ~10⁴-fold suppression at 20 µM without cytotoxicity (CC₅₀ > 40 µM; selectivity index >100). AM-001 also inhibited influenza A replication in Calu-3 cells with IC₅₀ ~1 µM. These effects reflect host-targeted EPAC1 inhibition rather than direct virucidal action. No in vivo animal model data were included in the study’s antiviral evaluation.