Baicalein exhibits favorable pharmacokinetics and potent antiviral efficacy against SVCV in carp via NF-κB activation and apoptosis inhibition

Spring viremia of carp virus (SVCV) inflicts substantial economic damage on global cyprinid farming operations, primarily affecting common carp and koi carp. Currently, no effective control measures exist. Baicalein, a flavonoid derived from Scutellaria baicalensis , exhibits broad-spectrum antiviral activity. This study investigated baicalein's inhibitory effects against SVCV in vitro and in vivo. Cytotoxicity assays demonstrated no observable toxicity in EPC cells at concentrations of 1–25 μg/mL. Transcriptome analysis and biochemical assays revealed that baicalein enhances innate immunity via the NF-κB pathway while concurrently suppressing SVCV-induced apoptosis. In SVCV-infected koi, baicalein treatment significantly reduced viral replication, attenuated pathogenicity, and improved survival rates. Pharmacokinetic studies in koi carp indicated favorable properties: rapid absorption (Tmax = 4 h), sustained plasma presence (t 1/2 z/h > 7 h), and dose-proportional exposure (AUC 0-t ). These findings establish baicalein as a novel therapeutic candidate against SVCV in aquaculture.