The drug is metabolized to the pharmacologically active nucleoside triphosphate metabolite after being distributed into cells (Figure 2). The triphosphate metabolite acts as a competitive inhibitor of RdRp and thus eventually causes chain elongation termination, which decreases the viral RNA replication [29]. The termination is delayed and happens after the addition of more nucleotides (between 3 and 5). Therefore, remdesivir is described as a direct antiviral agent acting as a delayed chain terminator [30,31]. Importantly, remdesivir avoids proofreading by viral exoribonuclease [28,32]. Currently, remdesivir is being evaluated as a treatment for COVID-19 patients in about 15 studies across the globe. The drug is being tested alone or in combination with merimepodib (NCT04410354; n = 40), tocilizumab (NCT04409262; REMDACTA; n = 450), or baricitinib (NCT04401579; ACTT2; n = 1034). In particular, merimepodib is another antiviral agent that is inhibitor of inosine monophosphate dehydrogenase. The enzyme is required for the synthesis of guanine nucleotides. Merimepodib consequently inhibits the synthesis of DNA and RNA, leading to antiviral and immunosuppressive effects. Thus, remdesivir and merimepodib is a dual-acting antiviral combination with immunosuppressive activity.