The concept of non-pharmacological mechanism of action in medical devices made of substances in practice: what pharmacology can do to promote the scientific implementation of the European medical device regulation

Summary
Medical devices represent a wide category of products intended to be used in the prevention, diagnosis, monitoring, treatment or alleviation of a disease or injury and their most recent evolution has led to an increasing number of products that include “substances” and which, due to their presentation and site of application are similar to medicinal products and are often referred to as “borderline” products. Regulatory documents in the European Union (EU) contemplate substance based products in many regulatory areas; in therapeutics, they distinguish “medical devices” from “medicinal products” according to the principal mechanism of action of the product. This difference is often not intuitive and is based on the correct interpretation of essential terms as “pharmacological, immunological and metabolic mechanism of action”, which have important regulatory implications. This paper addresses the issues concerning the correct interpretation of these terms and wishes to attract the interest of pharmacologists to design proper experimental paradigms to be applied to the rigorous and scientific interpretation of the correct mechanism of action of medical devices made of substances.