Fujitsu Laboratories today announced the development of molecular simulation technology for drug discovery that can accurately estimate binding affinity, which represents the degree to which proteins that can cause diseases (target proteins) bind to chemical substances that could become candidate drugs. In the process of drug discovery, there is a demand for accurate prediction of the binding affinity between target proteins and chemical substances, which offers a rough estimate of a drug’s efficacy. Molecular simulation technology has been widely used in the past as a method of predicting binding affinity, calculating the approximate forces that arise between atoms in molecules using Newtonian mechanics. The problem with this method, however, remains that the low degree accuracy of its estimation of the most important parameters-the degree of torsion at the binding sites. This means that the accuracy of its estimation of the overall binding affinity is also poor.