While the U.S. regulations on Medical Devices in general is rather copious, little or nothing was defined on the accessories before 2015.

In particular, neither the definition, the applicable classification, nor the applicable primary or amendment procedure for the marketing of the accessory on the U.S. territory was clear. This “oversight” was a cause of discontent for several associations of manufacturers, who had raised their concerns about the lack of FDA legislation on various occasions.

In January 2015, the “Medical Device Accessories: Defining Accessories and Classification Pathway for New Accessory Types” FDA Guidance was issued, which seeks at least to set out some basic points.

The definition of accessory and parent device are included in the preamble of this Guidance.

The accessory is defined as a “finished device intended to support, integrate and/or augment the performance of one or more parent devices”.

On the other hand, the parent device is defined as a “finished device whose performance is supported, supplemented and/or augmented by one or more accessories”.

When a device is considered an accessory

Even when it comes to accessories, FDA applies the same policy used to classify Medical Devices, i.e. based on the class of risk associated with their use for the intended use.

To determine whether a device can be considered an accessory, FDA defines two main criteria, explained through direct questions:

1 – Is the accessory intended to be used with one or more main devices?

If this claim is demonstrated by the labelling, promotional materials or methods of use, the product is considered an accessory and is subject to section 201 (h) of the FD&C law.

2 – Is it designed to support, integrate and/or augment the performance of one or more parent devices?

If the product augments/improves the performance of the main device and allows the device to be used more safely or effectively, then it is classified as an accessory. An accessory allows, for example, the main device to perform its function quicker, or improves the usability or comfort of use for the user.

Risks related to accessories and their regulation

As previously stated FDA evaluates the risk related to accessories and implements all the necessary controls to guarantee their safety and effectiveness. To this end, the risks related to the impact that the accessory has on the parent device, as well as any other risk closely linked to the accessory itself are taken into consideration.

The most suitable procedure for placing the accessory on the U.S. market is then established based on the aforementioned specified risk assessment.

How accessories are managed: classification and applicable regulations

 The FDA asks to manage the placing of accessories on the market according to the following procedures.

*** The first consists in including the accessory in the same risk and type class of the parent device, requiring for example the application of the Product Code of the parent device and the subsequent application of the relevant procedure (510 (k), exemption, PMA, etc.).

*** The second option, on the other hand, consists in the FDA issuing a new Product Code specific for the accessory. This option is usually employed for those types of accessories that could be used with multiple parent devices or those who have their own stand-alone functions.


THEMA - Logo TRASPARENTE_smallMarisa Testa
QA/RA Manager


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