Fig. 3: Efficacy of combination nirmatrelvir and remdesivir therapy against SARS-CoV-2-nsp5^T169Insp12^V792I virus in vitro.

Vero E6 cells were treated with indicated concentration of nirmatrelvir or remdesivir alone or in combination pre-infection (A), at the time infection (B) or at post-infection (C) and infected with 200 TCID₅₀/well of SARS-CoV-2-nsp5^T169Insp12^V792I. After 48 hours, the cell monolayer was fixed and stained with SARS-CoV-2 NP specific monoclonal antibody (red) and counterstained the nucleus with DAPI (blue). (D) Virus titration (TCID₅₀.mL⁻¹) in the supernatant of nirmatrelvir, remdesivir or combination treatment from A-C. The results represent four replicates from two independent experiments.