In a recent study published in "Chemico-Biological Interactions", Taroxaz-104 was found to exert potent toxic effects on the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also showed good efficacy against the newly evolved strains/variants of coronavirus such as VOC-202012/01.  Amgad M. Rabie undertook this study for computationally screening and examining the library of previously-synthesized oxadiazoles against the coronavirus protein targets.

Taroxaz-104 demonstrated considerably low binding energies with nCoV-RdRp-RNA and nCoV-RdRp alone. These binding energies were reported to be substantially reduced when compared with the standard reference drug GS-443902 (remdesivir potent active metabolite), as shown below:

Taroxaz-104 was found to exhibit about 43-fold anti-SARS-CoV-2 potencies as compared to GS-443902. Additional computational molecular assessment illustrated that this antioxidant ligand actively suppresses one of the important active sites of nCoV-RdRp (GS-443902 majorly interacts with this site). This is because it interacts with at least seven active amino acid residues of its predicted pocket.

Following the potential findings of the anti-COVID-19 biological assay, the successful repurposing of Taroxaz-104 has been achieved. It successfully suppressed the most crucial stage of the coronaviral-2 life cycle, the multiplication/transcription phase, with an anti-SARS-CoV-2 EC₅₀ value [half maximal effective concentration]  of 0.42 μM.

Thus, Taroxaz-104, a promising anti-COVID-19 agent, is also the first reported anti-VOC-202012/01 agent.