FDA tells manufacturers what it means to be an accessory

The FDA encourages manufacturers of medical device accessories to use the de novo classification process under Section 513(f)(2) of the Federal Food, Drug, and Cosmetic Act (FDC Act). In a new guidance document, the FDA explains the definition of accessory for FDC Act purposes, the regulation of such devices, and the process by which manufacturers can obtain a risk-based classification of a new accessory type.


Under Section 201(h) of the FDC Act, the definition of the term “device” includes “accessories.” Thus, all accessories to articles meeting the definition of device, are, themselves, devices. The classification of device accessories has historically taken on one of two methods: (1) shared classification with a “parent” device or (2) by issuance of a unique classification for the accessory. In the second circumstance, an accessory obtains a unique classification because the FDA determines that a classification regulation for an accessory should be separate from that of the corresponding parent device—a designation typically reserved for accessory types that may be used with multiple parent devices or that have unique standalone functions. However, the FDA recognized that some accessories have a lower risk profile than that of their parent device and, therefore, warrant a lower classification. Section 513(b) of the FDC Act was amended by the 21st Century Cures Act (P.L. 114-255) to reflect that thinking with a category of classification known as de novo classification.


After the FDA determines that an article is an accessory, the agency determines whether the article is intended for use with one or more parent devices and then asks whether the article is intended to support, supplement, and/or augment the performance of one or more parent devices. The guidance explains that an article does not become an accessory simply by virtue of the fact that it is used in conjunction with another device. For example, the FDA would not consider a mobile phone to be an accessory merely because it is used as a general platform for applications that include mobile medical applications that are themselves medical devices.

De novo classification

Under Section 513(f)(2) of the FDC Act, the FDA may classify an accessory of a new type under the de novo classification process. Such a classification request is a request for risk- and regulatory control-based classification of a new type of accessory. To fall into the classification of “new category type,” the accessory under consideration should not be previously classified or the subject of any approved premarket approvals (PMAs) or cleared 510(k)s for that accessory type. The de novo classification is intended as a pathway to Class I and Class II device classification for accessories for which general controls or general and special controls provide a reasonable assurance of safety and effectiveness, despite the lack of legally marketed predicate device.

Submission and classification

A manufacturer of a medical device accessory, who submits a de novo classification request, must include a description of the device and detailed information regarding the reasons for the recommended classification. The FDA is obligated to make a classification determination for the device, by written order, within 120 days of the request. If the submitter satisfies the regulatory criteria (i.e. presents an accessory for which general controls or general and special controls provide a reasonable assurance of safety and effectiveness) the FDA will grant the de novo request, classifying the new accessory (and new accessory type) as Class I or Class II. The FDA will then publish an announcement in the Federal Register of the new classification and the general and special controls necessary to assure safety and effectiveness for the device type.