These energies were then used to refine the scoring in a classical covalent docking algorithm. The method showed high sensitivity for retrieving active compounds and predicted seven human monoamine oxidase A inhibitors, which were experimentally confirmed. Cov DOX on the other hand uses hybrid quantum mechanical/molecular mechanical (QM/MM) calculations directly in its docking algorithm with 3 levels of potential energy refinement. The authors report a re-docking success rate of 81% for a benchmark set of 405 covalent ligand-protein complexes. Taken together, these results suggest that QM methods are favorable for refining the description of covalent systems.