Figure 2.

Antivirals’ intracellular metabolism and mechanisms of action are depicted in the figure. SARS-CoV-2 particles, after entering into the host cell, can reproduce via RNA-dependent RNA polymerase (RdRp). The enzyme is normally responsible for viral RNA replication, but it incorporates the active nucleotides analogs remdesivir and molnupinavir, either stalling or terminating the replication because of mutagenesis. Ritonavir is administered with nirmatrelvir to slow down its metabolic inactivation. The antiviral nirmatrelvir inhibits viral proteases responsible for the cleavage of structural proteins. Antivirals are depicted in graay boxes. Abbreviations. SARS-CoV-2: severe acute respiratory syndrome coronavirus 2, NHC-TP: β-D-N⁴-Hydroxycytidine 5′-triphosphate, CYP: cytochrome P450, RNA: ribonucleic acid, ACE2: angiotensin-converting enzyme, 3CLPRO: 3C-like protease.