Orphan drugs and the principles of their marketing authorization procedures and clinical use

One of the most complicated issues of modern medicine is diagnosis, treatment and prevention of rare diseases. In the structure of rare diseases the vast majority accounts for genetically determined disorders. The introduction of genetic testing methods helped to identify a lot of hereditary diseases, that currently reach the number of 8,000 cases and according to estimations the frequency of their detection is about to increase. Medicinal products for diagnosis or treatment of rare diseases form the group of orphan drugs. Biologicals are the most effective medicinal products in the whole group, due to their ability to bind specifically with the «target receptor», which allows to use them as targeted drugs. Another advantage of biologicals, compared with preparations of chemical origin, is their low toxicity. Orphan drug provision is the most severe issue because the treatment of severe forms of rare diseases may require the prescription of an expensive drug. Manufacturing of orphan drugs may be unprofitable for the reason of the low prevalence of rare diseases. Therefore, the availability of orphan drugs for patients depends on the amount of state participation in manufacture stimulation. In various countries regulatory requirements for the recognition of a disease as a rare disease, and marketing authorization procedures for orphan drugs are developed with due regard to the social and economic characteristics of the country. The article presents the analysis of the regulatory requirements for various countries for the detection of rare diseases, and a common approach to marketing authorization procedure for the drugs used in treatment of rare diseases, exemplified by biological orphan preparations.