Fig. 6. Therapeutic oral efficacy of 4′-FlU against different SARS-CoV-2 isolates in ferrets.

(A) Single oral dose (15 or 50 mg/kg bodyweight) pharmacokinetics properties of 4′-FlU in ferret plasma (n = 3). (B) Ferrets were inoculated with SARS-CoV-2 WA1 or VoC alpha, gamma, or delta, and treated as indicated. (C) Nasal lavages were performed twice daily and viral titers were determined by plaque assay [n = 4 (WA1) or n = 3 (alpha, gamma, delta)]. (D) Viral titers in nasal turbinates at day 4 post-infection. In all panels, symbols represent individual independent biological repeats and lines show mean values. Two-way ANOVA with Sidak’s post hoc multiple comparison (C) and unpaired t-test (D).