Topicality. A detailed study of the physicochemical and biopharmaceutical properties of medicinal substancesshould be carried out at the initial stage of the pharmaceutical development of the finished dosage form of a drug in order to avoid destructive transformations that can occur in the process of manufacture and storage, prediction of bioavailability, pharmacological efficacy and safety of medicinal products in the human body, as well as speed up the scientific work to determine the optimal composition and technology for new drugs.Aim. To study a physico-chemical and biopharmaceutical properties of the poor soluble medicinal substances riluzole and nimodipine for predicting the optimal composition and technology of generic drugs.Materials and methods. Samples of riluzole and nimodipine substances are obtained according to the technology, which is developed by the laboratory of chemical synthesis of the PJSC “Borshchahivskiy CPP”(Kiev, Ukraine) and also samples of tablets original drugs Rilutek, film-coated tablets, 50 mg, company “Sanofi”, France and Nimotop, film-coated tablets, 30 mg, company “Bayer AG”, Germany. All analytical and pharmaco-technological researches were implementedaccording to generally accepted methods that accordance with the requirements of the State Pharmacopoeia of Ukraine.Results and discussion. Physicochemical properties such as the chemical structure of molecules, the size and shape of particles of substances, the possibility of chemical interaction of substances with different excipients, the melting temperature, lipophilicity and solubility in organic and aqueous solvents for the substances riluzole and nimodipine were studied. The study of the biopharmaceutical properties of substances was carried out by study in vitro release kinetics of the substances riluzole and nimodipine from the tablets of the original drugs “Rilutec” and “Nimotop”.Conclusions. Studies of the physico-chemical and biopharmaceutical properties of the medicinal substances riluzole and nimodipine made it possible to predict compatibility of substances with excipients and suggest the most optimal technology for generic drugs Borizol 50 mg film-coated tablets and Nimodipine 30 mg film-coated tablets.