Accessories to medical devices play an integral role for their parent medical devices, supporting or adding to the parent device’s functionality.  Accessories historically took the classification of the parent device, except in cases where the Food and Drug Administration (“FDA”) classified the accessory in its own right.    The 21st Century Cures Act, passed into law on December 13, 2016, directed FDA “to classify an accessory based on the intended use of the accessory, notwithstanding the classification of any other device with which such accessory is intended to be used.”  To this end, FDA published a Guidance Document, Medical Device Accessories – Describing Accessories and Classification Pathway for New Accessory Types, that describes how FDA intends to classify new accessory types.
Accessory Classification Policy
FDA will determine an accessory’s classification by applying the same risk and regulatory control-based criteria that it currently does for other medical devices, according to the Accessory Classification Policy outlined in the Guidance Document.  FDA considers an accessory’s risks to be those it presents when used with the corresponding parent device, when used as intended.  FDA asks two questions to assess the accessory’s risk.
Is the article an accessory?  To determine whether a product is an accessory, FDA examines whether the product is intended for use with one or more parent devices, and whether it is intended to support, supplement, and/or augment the performance of the parent device.    An accessory should be intended for use with one or more specific parent devices. Equipment such as an off-the-shelf computer monitor would not be an accessory unless it is specifically intended for use with a medical device.  Such products may not be independently classified if they are not accessories to medical devices.
What are the risks of the accessory when used as intended with the parent device(s) and what regulatory controls are necessary to provide a reasonable assurance of its safety and effectiveness?  To answer this question, FDA intends to evaluate the risks imposed by the accessory’s impact on the parent device and any unique risks of the accessory independent of the parent device.  Not all risks of the parent device are imputed to the accessory, and likewise, the accessory may pose a different set of risks that the parent device may mitigate.
Next Steps
FDA recommends new accessory type manufacturers to use the de novo classification process at Section 513(f)(2) of the Food, Drug, and Cosmetic Act to request classifications for the new types of accessories.  Accessories that are already classified by an existing classification regulation or that are the subject of an already-approved PMA or 510(k) are not new accessory types, and need not be reclassified at this point in time.  Appendix 1 in the Guidance Document includes the information that FDA recommends accompany the de novo request for a new type of accessory.