Likewise, lapatinib treatment dose-dependently suppressed infection of Calu-3 and Vero cells with replication-restricted pseudovirus bearing SARS-CoV-2 spike (S) protein (rVSV-SARS-CoV-2-S) as measured by luciferase assays (EC50 = 2.6–3.2 μM, CC50 > 20 μM) (Figure 2, E and F), suggesting that lapatinib inhibits viral entry. This evidence concerns the gene PROS1 and infection.