The interaction of the derivatives of favipiravir, including 6-chloro-3-hydroxy-pyrazine-2-carboxamide (C5H4ClN3O2) and 6-bromo-3-hydroxy-pyrazine-2-carboxamide (C5H4BrN3O2) molecules, on the B12N12 cluster as a potential antiviral treatment for COVID-19 diseases, was investigated using the PBE1PBE-D3/6-31+G** method in both gas and solvent environments. The calculations showed that the adsorption of C5H4ClN3O2 and C5H4BrN3O2 molecules, on the B12N12 cluster is strong, forming a covalent bond (B-N) between the boron atom of the cluster and nitrogen atom of the molecules, with adsorption energies of -21.419 and -24.524 kcal/mol for B12N12/C5H4ClN3O2 complex, and -23.552 and -26.753 for B12N12/C5H4BrN3O2 complex in gas and water phases, respectively. The vibrational frequency calculations indicated that the resulting complexes are structurally stable, and the ΔH and ΔG values for the processes are negative. The significant changes in the polarity of the complexes and Esol value demonstrated that the B12N12 cluster can be used as a promising delivery vehicle for the molecules. The reactive sites of the molecules were investigated by MEP analysis. The significant reduction in energy gap values of the complexes after the interaction of B12N12 with the molecules (47.28%) showed the higher sensitivity of the B12N12 for detection of the molecules. Finally, the anti-viral activity of the C5H4ClN3O2 and C5H4BrN3O2 molecules and their complexes towards the COVID-19 main protease (PDB ID 5R82 and 6LU7) was studied by docking. Molecular docking showed that the B12N12/C5H4BrN3O2 complex, as a new compound, can bind to the active position of the 6LU7 receptor and may represent an antiviral drug for the novel treatment against COVID-19