Repurposing FDA-Approved Antiviral Drugs Ganciclovir and Acyclovir Against Respiratory Syncytial Virus Nucleoprotein: Molecular Docking, ADMET, PASS, and Molecular Dynamics Simulations.

Respiratory syncytial virus (RSV) is a prevalent viral respiratory infection that has been increasingly affecting children under 5 years old globally. Although RSV can infect individuals of all ages, certain groups are at higher risk, particularly infants and young children. This growing concern underscores the urgent need for effective therapeutic options. In this context, drug repurposing emerges as a promising strategy, allowing existing medications to be utilized for new therapeutic applications beyond their original indications. In this research, we utilized library of FDA-approved antiviral drugs that show potential for repurposing. We performed molecular docking against RSV nucleoprotein. The two resulting drugs, ganciclovir and acyclovir, reveal notable binding energy and critical interactions. Further ADMET profile and prediction of activity spectra for substances (PASS) analysis show potential to be antiviral drugs against nucleoprotein. Furthermore, molecular dynamics simulations for 500 ns were conducted, along with calculations of principal component analysis (PCA) and Gibbs free energy for the most promising ligand-receptor complexes identified in docking ADMET and PASS analysis (ganciclovir and acyclovir). The simulations provided insights into their thermodynamic and dynamic properties, further investigating the docking results. The findings from this study offer valuable leads for the development of therapeutic agents against RSV. However, to substantiate the preventive and therapeutic potential of these compounds, further validations, including in vitro, animal studies, and rigorous clinical trials, are necessary.