Azvudine potently inhibits African swine fever virus replication in vitro.

African swine fever (ASF), caused by the African swine fever virus (ASFV), is a highly contagious and often fatal disease affecting domestic pigs and wild boars, resulting in substantial economic losses globally. The lack of commercially available vaccines or effective antiviral drugs highlights the urgent need for novel therapeutic strategies. In this study, we conducted a cell-based screening of a targeted anti-DNA virus compound library to identify inhibitors of ASFV replication. Among the candidates, Azvudine-a clinically approved nucleoside analog-demonstrated potent dose-dependent suppression of ASFV replication in porcine alveolar macrophages (PAMs), with a half-maximal inhibitory concentration (IC50) of 0.19 μM and minimal cytotoxicity. Further mechanistic studies indicated that Azvudine acts at a post-entry stage of the viral life cycle and does not directly inactivate viral particles. These findings suggest that Azvudine is a promising repurposed candidate for anti-ASFV drug development.