Final EU guidance issued on clinical evaluation of coronary stents
This article was originally published in RAJ Devices
Final guidance from the European Commission on the clinical evaluation of coronary stents describes the main requirements for the clinical evaluation of this group of Class III medical devices based on current state-of-the-art and on experience drawn from the most recent reviews of clinical studies1.
The guidance covers bare metal stents, drug-eluting stents and other innovative stents, such as those with a novel active coating, biodegradable stents or stents requiring novel clinical techniques for placement. For coronary stents incorporating a medicinal substance, notified bodies need to refer to a member state competent authority for drugs or the European Medicines Agency for their scientific opinion.
The guidance is included as an Appendix to MEDDEV 2.7.1 on guidance to manufacturers and notified bodies on evaluation of clinical data. It takes into account comments received to the draft guideline that was issued in March 20082. The document covers preclinical assessment, clinical investigation, evaluation of clinical data supporting CE marking, postmarket clinical follow-up and modifications to stents or indications for use.
Sponsors are warned against making generic claims for devices that have been studied in limited patient populations. “Specific claims must be backed up by specific clinical data,” the document states. In terms of investigation design, it says that this must be based on the claims made by the manufacturer and as part of the demonstration of compliance with the essential requirements of the Medical Device Directive. Controlled randomised studies should be conducted when necessary to substantiate claims made by the manufacturer, it adds.
In terms of how long a clinical investigation should last, the guidance recommends a minimum timeline of six months in general for bare metal stents and a minimum of 12 months for drug-eluting and other innovative stents, although it notes that longer timelines may be required. The document outlines performance endpoints for device and procedural success which should be included, as well as clinical endpoints. Reference is made to the Academic Research Consortium Publication, which recommends using composite endpoints. These endpoints include target vessel failure/major adverse cardiac events; this is a composite endpoint that may vary from investigation to investigation and, therefore, the components should be specified, the guidance notes.
Postmarket clinical follow-up is required for all drug-eluting stents and innovative stents, and for all bare metal stents unless duly justified. These programmes can take the form of a clinical investigation and/or registry and should last for a minimum of three years.
The impact of subsequent modifications of claims or design iterations to marketed coronary stents must be evaluated on the basis of risk-analysis to determine whether further preclinical testing or clinical investigation is required. Each claim modification should be approved by the relevant notified body. Modifications influencing specified drug characteristics and/or drug delivery characteristics require consultation with the appropriate competent authority or the EMEA.
References
1. European Commission, Guideline on clinical evaluation of coronary stents, Appendix 1: Clinical Evaluation of Coronary Stents, December 2008, http://ec.europa.eu/enterprise/medical_devices/meddev/cetf.pdf
2. The Regulatory Affairs Journal - Devices, 2008, 16(3), 182-183