From Definitions to Regulations of Medical devices and Materials
Figure 1. Biologics fates and adverse sequelae to permanent biomaterials and medical devices. Modified from Springer, Integrated Safety and Risk Assessment for Medical Devices and Combination Products by Shayne C. Gad, p. 369. © 2019.
Figure 2. Biologic fates and adverse sequelae to biodegradable biomaterials and medical devices. Modified from Springer, Integrated Safety and Risk Assessment for Medical Devices and Combination Products by Shayne C. Gad, p. 369. © 2019.
Regulatory Classification of Devices
Medical device regulation encompasses a multifaceted framework comprising diverse standards, guidelines, and related documents. Due to the dynamic nature of these documents and the evolving nature of laws, it is crucial to continuously review the most up-to-date materials during the design and implementation of medical device studies.
The classification of medical devices is determined based on their risk level. Generally, Class II devices (including IIa and IIb), as well as high-risk devices such as Class III and active implantable medical devices (AIMDs), or Class IV devices in certain countries, are subject to stringent nonclinical and clinical controls and efficacy testing to ensure safety. These devices also necessitate adhere to Good Manufacturing Practices (GMPs) or Quality Management Systems (QMSs).
On the other hand, Class I devices (including Class I basic, I sterile, or I measuring), along with some Class II devices, may undergo self-assessment by the innovator, with minimal in vivo testing for safety and efficacy, provided they demonstrate substantial equivalence to a “predicate device” recently or previously available on the market. Exempt from 510(k) or Premarket Approval (PMA) applications and pre-marketing safety and efficacy approvals are Class I devices. However, Class II devices require GMP and may necessitate unique controls to demonstrate safety and efficacy based on their intended use. For instance, intraocular lens guides are not exempt if used as a folder or injector for soft and foldable intraocular lenses.
In various countries and areas, including the European Union (EU), European Economic Area (EEA), United Kingdom, Canada, Australia, and New Zealand, only nonsterile, non-measuring Class I devices are exempt from regulatory applications before registration and manufacturing. However, post-marketing surveillance may still be required.
While device classification can often be determined by referring to predicate devices, it is essential to consult country-specific information to verify device classification and the appropriate testing approach. Novel biomaterials or devices may necessitate direct engagement with regulatory agencies. Moreover, to ensure product safety, medical device registration might require a country-specific unique device identification (UDI) and a standardized device group descriptor and code, employing the Global Medical Device Nomenclature (GMDN).
The UDI system is adopted by the United States, China, South Korea, Saudi Arabia, and Taiwan, with its introduction currently underway in the EU and the United Kingdom. The GMDN is utilized by the FDA, Canada, EU, Brazil, Australia, New Zealand, Russia, Saudi Arabia, Turkey, and more recently in the United Kingdom as part of its separation from the EU (Brexit). The EU favours the European Medical Device Nomenclature, which is cross-referenced with the GMDN for comprehensive code searching.
The standards for medical devices have experienced independent development compared to those for pharmaceuticals and biologics. Most of the medical device development is directed by international and country-specific testing standards organizations, such as ASTM (American Society for Testing and Materials) and ISO (International Organization for Standardization), rather than the International Council for Harmonisation (ICH) or individual government regulatory agency guidelines.
A recent comprehensive review has examined the current standards and regulatory guidance documents relevant to the development of medical devices.  It is important that the standards and regulatory control of medical devices are rapidly evolving. Therefore, it is essential to consult the most up-to-date versions of existing standards and any new standards or regulatory guidelines when designing and reporting studies.
The issuance of these standards and regulatory guidelines plays a crucial role in ensuring the development of safe, effective, and high-quality medical devices. They provide a framework for manufacturers, researchers, and regulatory bodies to establish consistent practices, evaluate device performance, and protect public health. Given the dynamic nature of standards and regulations in this field, it is imperative to stay informed about the latest developments to ensure adherence and compliance in study design and reporting for medical device development.
Note: This article is based on Wancket, L.M., J.C. Schuh, and E. Drevon-Gaillot, Biomedical materials and devices, in Haschek and Rousseaux’s Handbook of Toxicologic Pathology, Volume 2: Safety Assessment Environmental Toxicologic Pathology. 2023, Elsevier
Authors: Juan Uribe-Gomez, Bohara Raghvendra
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