A method for computational modeling and simulation applied to drug characterization and/or optimization is described. The method comprises the step of storing on a computational platform 1 digital data for modeling characteristics of an individual D1, digital data for modeling characteristics of an animal D2, digital data for modeling properties of chemical and/or biological compounds and/or drugs D3, digital modeling data of biological targets D4, digital modeling data of disease features and/or therapeutic areas D5 towards which the drug is directed. The method then comprises the step of receiving selection and/or setting information I which can be entered by a user through a user interface 4 which can be connected to the Internet. Such information include information on selection and/or definition and/or setting l1 of a pharmacometric and/or physiological model; information on selection and/or definition and/or setting I2 of a chemical and/or pharmacological and/or biological system model; information on selection and/or definition and/or setting I3 of a screening and/or optimization model; information on selection and setting I4 of a modeling and/or simulation type, and/or information on selection and setting I5 of one or more modeling and/or simulation input parameters and information on selection and setting I5 of one or more modeling and/or simulation output parameters I6. The method then comprises the step of processing, by means of the computational platform 1, the aforementioned types of selection and/or definition and/or setting information to develop a pharmacological and/or physiological model M1 (based on the digital modeling data of an individual D1 and/or digital modeling data of an animal D2), a chemical and/or pharmacological and/or biological and/or therapeutic system model M2 (based on digital modeling data of chemical and/or biological compounds and/or drugs D3 and/or digital modeling data of biological targets D4 and/or digital modeling data of diseases and/or therapeutic areas D5), and a screening and/or optimization model M3 (based on digital modeling data of disease features and/or therapeutic areas D5 and also on the aforementioned digital modeling data of chemical and/or biological compounds and/or drugs D3 and/or digital modeling data of biological targets D4). Then, the selection and/or setting information I entered by the user is processed for preparing input setting data Din for one or more computational modeling and/or simulation software programs included in the computational platform. The method then comprises executing computational modeling and/or simulation, by the one or more computational modeling and/or simulation software programs, on the basis of the abovementioned input setting data Din, and based on the pharmacometric and/or physiological model M1, on the chemical and/or pharmacological and/or biological system model M2, and on the screening and/or optimization model M3, to obtain computational modeling and/or simulation output data Dout. Finally, the method comprises the step of processing the computational modeling and/or simulation output data Dout, on the basis of the information on selection and setting l6of one or more modeling and/or simulation output parameters, to report the requested modeling and/or simulation results R in a format selected by the user, and the step of providing such requested simulation results through the user interface 4.