Relevant issues to biossimilars licensing.

When the patent of a drug expires, low cost generics may be introduced in market. Trial results that demonstrate the safety and efficacy of the reference product can be extrapolated to the generic, simplifying the approval process. This paradigm cannot be applied to biopharmaceutical products, large molecules difficult to be characterized. Minor changes in the production process can influence the biological and clinical properties of the product and result in differences in efficacy and safety profiles. It is not possible to demonstrate the identical nature of biopharmaceuticals arising from different manufacturing sources, so they cannot be approved as simple generics and need specific regulation. A bibliographical survey of the main issues involved in the approval of similar versions of biopharmaceuticals was performed as well as a comparative analysis of the regulatory situation in the largests pharmaceutical markets - U.S. and European Union - based on legislation, draft laws, guidelines and technical references issued by their regulatory agencies - FDA (Food and Drug Administration) and EMEA (European Medicines Agency), respectively, in order enlight the discussion now taking place in Brazil. Based on the laws and guidelines studied, it is concluded that, although Brazil, Europe and the United States are at different stages of setting their regulatory framework for biossimilars, it is possible to identify some similarities in approach, such as the need for different treatment for each product class (or a case by case focus) and a step by step comparison exercise, the results of which will define the amount of data and non-clinical and clinical studies required. However, issues such as interchangeability and automatic substitution of biossimilars for reference products are not yet clearly defined. From the sanitary point of view, Europe has a more conservative posture, while the U.S. and Brazil seem to be building a more flexible framework. Besides the health issues, however, we highlight the economic issues, of great importance in Europe and U.S. legislation, and not addressed in the Brazilian regulation - which can bring insecurity to producers interested in this market.