Researchers from the Grenoble Interdisciplinary Research Institute (IRIG) and the CEA’s Joliot Institute are working on the search of inhibitors in COVID-19. The SPIKE protein allows the virus to penetrate the cell membrane. Thanks to the simulation of the electronic structure of the protein and the associated inhibitor, it is possible to provide precise information on the strength of the inhibition but also structural information to identify the amino acids concerned and their associated polarities. This initial work made it possible to validate the approach and thus to submit a 15 million hour project to PRACE to study the microscopic and thermodynamic factors that may or may not favour the interaction between the main SARS-CoV-2 protease and promising new inhibitors. The objective is to build an ab initio in silico tool to estimate accurately the interaction properties of proteins interacting with all types of ligand families.