The ESMO Precision Medicine Glossary

Abstract

In the latest edition of Annals of Oncology, the European Society for Medical Oncology (ESMO) has published a Precision Medicine Glossary, which without doubt will be welcomed by scientists and healthcare professionals within oncology as well as other medical disease areas [1.Yates L.R. Seoane J. Le Tourneau C. et al.The European Society for Medical Oncology (ESMO) Precision Medicine Glossary.Ann Oncol. 2018; 29: 30-35Abstract Full Text Full Text PDF PubMed Scopus (63) Google Scholar]. The ESMO glossary defines 43 different terms related to precision medicine; however, one important term is missing and this is ‘companion diagnostics’. Over the past 20 years, we have seen an increasing number of targeted cancer drugs being developed using the drug-diagnostic codevelopment model. In this model, a companion diagnostic assay is developed in conjunction with the drug and used to define the patient population likely to benefit. For a number of targeted cancer drugs these assays have played a critical role in their successful development [2.Hersom M. Jørgensen J.T. Companion and complementary diagnostics-focus on PD-L1 expression assays for PD-1/PD-L1 checkpoint inhibitors in NSCLC.Ther Drug Monit. 2017 October 27; Crossref Scopus (67) Google Scholar]. These companion diagnostic assays are not only important during the drug development process but also essential treatment decision tools after the approval of the drug. The companion diagnostic assay has the individual patient as a point of reference and they are decisive for the move toward a more individualize pharmacotherapy and an important element in the realization of precision medicine [3.Jørgensen J.T. Companion and complementary diagnostics: clinical and regulatory perspectives.Trends Cancer. 2016; 2: 706-712Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar]. As the authors probably are aware of, the European Union (EU) has recently got new legislations on in vitro diagnostic medical devices. In April 2017, the European Commission and the European Parliament adopted the new regulations, which also included a definition of a companion diagnostic assay [4.Regulation (EU) 2017/746 of the European Parliament and of the council of 5 April 2017 on in vitro diagnostic medical devices and repealing Directive 98/79/EC and Commission Decision 2010/227/EU. http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32017R0746 (8 December 2017, date last accessed).Google Scholar]. According to the new regulations, a companion diagnostic assay is a device which is essential for the safe and effective use of a corresponding medicinal product. In addition to the overall definition, the European Regulators emphasizes two subareas where a companion diagnostic could be essential for the safe and effective use of a corresponding medical product, and they are: (i) to identify, before and/or during treatment, patients who are most likely to benefit from the corresponding medicinal product; or (ii) to identify, before and/or during treatment, patients likely to be at increased risk of serious adverse reactions as a result of treatment with the corresponding medicinal product [4.Regulation (EU) 2017/746 of the European Parliament and of the council of 5 April 2017 on in vitro diagnostic medical devices and repealing Directive 98/79/EC and Commission Decision 2010/227/EU. http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32017R0746 (8 December 2017, date last accessed).Google Scholar]. This new EU definition is similar to the one that has been used by the US FDA for several years. In the introduction to the glossary, the authors stated that it should provide a resource to facilitate a consistent communication in the field of precision medicine between the different stakeholders, which makes it even more important that the term ‘companion diagnostic’ is included here. Furthermore, in the introduction the authors emphasize that the glossary will be a dynamic entity undergoing expansion and refinement over the coming years, and my recommendation for the next edition will be to include the term ‘companion diagnostics’.