Figure 2.

Dose–response curves of GZ-161 and GZ-346 for inhibition of SARS-CoV-2 infection. Graphs depict the mean % inhibition of SARS-CoV-2 replication (blue circles, left Y-axis) and % cytotoxicity (red squares, right Y-axis) of antivirals. Vero E6 cells were infected in four replicates with SARS-CoV-2 at a multiplicity of infection (MOI) of 0.01 in the presence of drug doses for 24 h, after which viral release was measured through quantitation of SARS-CoV-2 RNA levels by real-time PCR. Cytotoxicity was measured in similarly treated but uninfected cultures via the Cell Proliferation Kit (XTT based). Representative data are shown from three independent experiments. The IC₅₀ is the concentration on an antiviral required at which virus replication is inhibited by 50% in a cell-based assay. The cytotoxic concentration 50 (CC50) is the concentration of an antiviral agent required to kill 50% of cells in the uninfected culture. SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.