Transition to clinical studies without in vivo studies in non-clinical trials during biosimilar application processes

In this study, the aim was to investigate the possibility of advancing to non-clinical trials in biosimilar application processes without conducting in vivo studies, thus accelerating the entry of drugs into the market. According to Section 4, Article 15 of the Guideline on Biosimilar Medicinal Products, prepared based on the Human Medicinal Products Licensing Regulation published and enforced by the Turkish Medicines and Medical Devices Agency, it is stated that clinical trials can continue without resorting to in vivo studies once sufficient data is provided. However, this article does not provide detailed information on what constitutes sufficient data and how it should be evaluated. The lack of detailed information creates uncertainty in the most critical part of the biosimilar development process, which is the comparative studies. Literature reviews were conducted under the headings of determining the adequacy of data obtained from comparative quality analyses, the feasibility of using in vitro experiments instead of in vivo experiments, and the impact of data obtained from in vivo experiments on biosimilarity comparison. Animal studies conducted for approved biosimilars in Europe, America, and Turkey were considered to form a general overview. Taking into account the table and literature studies, it has been concluded that regulators in Europe, America, and Turkey can continue the application process without implementing in vivo experiments, and that it is possible to obtain reliable data through advanced in vitro methods instead of in vivo experiments in light of technological advancements. Encouraging regulators and applicants to skip the in vivo step will expedite the process of biosimilars taking their place in the pharmaceutical market, supporting both human and animal health.