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Generic drug manufacturers apply for marketing approval of generic drugs under the Abbreviated New Drug Application (ANDA) pathway established by FDA. Moreover, generic drug applications are termed “abbreviated” because they are generally not required to include preclinical and clinical data to establish safety and effectiveness. The generic manufacturer needs to demonstrate only pharmaceutical equivalence and bioequivalence between the generic and innovator products, in order to gain approval for their generic product. This approach cannot be extrapolated to biosimilars, however, because the active substance of a biopharmaceutical is a collection of large protein isoforms and not a single molecular entity, as is generally true for conventional small molecule drugs. Thus, the active substances in two products are highly unlikely to be identical and, therefore, unlike generics, biosimilars are only highly similar and not identical to the innovator products. These differences imply that biosimilars should not be approved and regulated in the same way as conventional generic drugs. The regulatory pathway for approval of biosimilars is more complex than for the generic innovator product because the design of a scientifically valid study to demonstrate the similarity of a highly process‐dependent product is not easy. Further, the analytical tests currently available are not sophisticated enough to detect the slight but important structural differences between innovator and biosimilar products. Modest differences may have clinical implications and pose a significant risk to patient safety. Therefore, it is considered necessary that biosimilars must be assessed for clinical efficacy and safety by valid preclinical and clinical studies before marketing approval.¹

To maintain a sustainable launch of biosimilars, organizations must plan the market entry by considering the local administrative and regulatory conditions and aligning their launch strategy accordingly. Most developing markets that have such an administrative system have modeled it on those of the World Health Organization (WHO) or the European Medicines Agency (EMA). With the introduction of biosimilars, it was considered that the rules set up for generic small molecules were not reasonable to replicate for the approval of biosimilars. Starting with the EMA in 2005, regulatory jurisdictions around the globe started to create and execute explicit regulatory frameworks for biosimilars to guarantee the generation of safe and effective medications.

The approach established for generic medicines is not suitable for development, evaluation and licensing of similar biotherapeutic products (SBPs) since biotherapeutics consist of relatively large and complex proteins that are difficult to characterize.

– The World Health Organization

There are presently 36 nations, spread across most geographic regions of the world, that have biosimilar guidelines set up that regulate the approval and registration of these medications. Such guidelines provide biosimilar manufacturers/sponsors with guidance and direction on the most suitable method to demonstrate biosimilarity with the innovator/reference biologic including guidance on nomenclature/naming and demonstrating comparability for biosimilar drugs.²