Main concepts on bioequivalence and biosimilarity in the Chilean legislation, and current controversies on drug...

Medicines are an economic good and a fundamental component of public and private spending and health decision-making. Assurance of their quality, efficiency and safety is essential. However, the variety of products on the Chilean market, including innovative and generic productsthe latter accounted for by many products that are certified as bioequivalent while others are notresults in a potentially confusing scenario for consumers and health providers. In this review, we intend to shed light on the concepts of bioequivalency (applicable to compounds of small molecular size) and biosimilarity (applicable to biological compounds of greater molecular complexity). In both cases, how the active substance interacts with the host organism must be demonstrated by studies carried out for this purpose. A direct application of the concept of bioequivalence is interchangeability, defined as the possibility of using a product of the same active principle, as long as the pharmaceutical form and dosage scheme are the same. Regulations related to bioequivalence and biosimilarity must not only guarantee safety and efficacy when products are interchanged, but also facilitate cost savings and access to medicines. Likewise, the implementation of evidence-based guidelines that standardize concepts of interchangeability should be encouraged, as this could lead to a more educated usage and a reduction in the information asymmetry between patients (users) and the industry. The importance of interchangeability of medicines is particularly relevant in two governmental health initiatives in Chile: the Explicit Health Guarantees Plan (GES) and the Financial Protection for Diagnoses and Treatments of High Cost, known as the Ricarte Soto Act. Nonetheless, it is not possible to guarantee that all alternative products to an innovative drug on the Chilean market are bioequivalent. The synthesis of knowledge available on this subject may impact and contribute to decision-making by stakeholders. It could also help to develop better health policies regarding bioequivalent and biosimilar pharmaceutical products in our country.