Anti-TNFs: Originators and Biosimilars

Abstract

In the last 20 years, the advent of anti-tumor necrosis factor alpha (TNFα) biologics has revolutionized the treatment of patients with inflammatory bowel disease (IBD) but the cost of biologic therapy now constitutes a large proportion of all healthcare expenditures. Patent expiration has sparked the healthcare industry's interest in the production of biosimilar (BS) versions of first generation biologics (originators [ORGs]) for market sharing. Having no access to the production line of the ORG, the sponsor of a BS needs to develop his own manufacturing process to produce a highly similar version of the reference product. Similarity in structure, physicochemical properties, biologic activity, efficacy and safety must be demonstrated by a comprehensive comparability exercise that includes the most sensitive in vitro tests, models and clinical condition with pre-defined equivalence margins. Extrapolation of indications, inter-changeability and automatic substitution between BS and ORG depend on a legal framework that varies between different agencies. It is not, therefore, unexpected that marketing authorization by the European Medicines Agency and other regulatory agencies (but not Health Canada) of CT-P13 (Remsima/Inflectra) as infliximab (Remicade) BSs for IBD by indication extrapolation has led to stormy discussions in the IBD community and beyond regarding the scientific adequacy of this decision. However, as we now have to live with BSs, we hope that the impeding automatic substitution in association with post-marketing pharmacovigilance, full traceability, registries and new studies will settle the controversy and will increase the confidence of physicians and patients. A universally adopted legal framework should be implemented because, as expected, the non-anti-TNFα BSs will be soon on the stage.