A Computational Study of Ivermectin and Doxycycline Combination Drug Against SARS-CoV-2 Infection

docked pose position (Table 2 ). For doxycycline: protein complex, pose 7 is the better interacted position with the binding affinity of -6.4 kcal/mol, dreiding energy; 6,063.5, dipole moment; 6.104 Debye, inhibition constant; 2.0 X 10 -5 M and 7 number of hydrogen bonds (Table 2 ). Best pose of the donor-acceptor surface with their possible hydrogen bonding and hydrophobic interactions 3D and 2D view are shown in Figure 3b . Our result shows that out of two possible ligand drug structures, ivermectin represents the best potentiality to inhibit with the SARS 3CL pro (6LU7) by its best docking affinity compared to the doxycycline. Good binding mode of interactions of ivermectin: protein complex also verified by its less binding energy, minimum inhibition constant value as compared to doxycycline. Both the drug molecules showed good stability as a complex with the targeted protein. These drug molecules also satisfy the required drug likeness properties according to Ro5, Veber etc. rules, polar surface areas and logP values. RMSD corresponds to any change in the conformational stability of the protein: drug complex and in the protein dynamics. RMSD of the free protein and protein: ligand complex have been simulated to 100000 psby using MD simulations. RMSD and RMSF have been measured by using the GROMACS module at an interval of 1000 ps. RMSD variation of apo 3CL pro lies in the range from 0.08 to 0.16Å. Ivermectin: 3CL pro , doxycycline: 3CL pro , ivermectin+doxycycline: 3CL..