Interchange of biosimilar medicines: effective, safe and efficient

Abstract

INTRODUCTION AND OBJECTIVES A biosimilar is a biological medicine that is very similar to another one already marketed in the European Union (EU) whose patent has expired and the differences between which are not clinically significant, in other words do not affect clinical practice. More biosimilars are slowly being developed and, consequently, the experience with their use is increasing. The European Medicines Agency (EMA) considers the biosimilars approved in the EU to be interchangeable, and has signed a statement to reduce the uncertainty regarding interchangeability of biosimilars in clinical practice. The aim of this bulletin is to define the basic concepts, describe the comparability, authorisation and interchangeability processes, evaluate the scientific evidence regarding the efficacy, safety and economic impact of the switch, and to describe the current situation of biosimilars in Spain. MATERIALS AND METHODS A literature search was carried out for systematic reviews evaluating the efficacy/effectiveness, safety and immunogenicity or economic impact of the switching in Pubmed and Epistemonikos up to 28/11/2022. Documents from regulatory agencies and other publications of interest were also reviewed. Data regarding the consumption and economic impact of biosimilars in Spain were obtained from the Ministry of Health, and those for Navarre were obtained from the information databases of the Navarre Health Service-Osasunbidea (SNS-O). RESULTS AND CONCLUSIONS In general, the evidence available demonstrates that the switching of a reference medicine for a biosimilar does not affect the efficacy, safety or immunogenicity in any significant manner. Some reviews have identified a higher than expected discontinuation rate for the biosimilar after the switch, mainly due to a potential nocebo effect and a lack of confidence of healthcare professionals in the switching. A total of 147 biosimilar medicines are currently marketed in Spain, corresponding to 15 active substances. The introduction of biosimilars in Spain continues to increase, with a penetration of 67.6% having been estimated in a hospital setting in 2021. Similarly, a saving of more than 5 billion € between 2009 and 2022 as a result of their introduction has been estimated.