Call for comments: FDA wants feedback on the distinct classification of existing device accessories into Class I

A push to classify accessories independently

The classification of medical device accessories by FDA has evolved significantly over the past decade, driven by the recognition that accessories often have risk profiles distinct from those of their parent devices. This shift reflects a broader movement within FDA toward risk-based regulation and tailored oversight.

Traditionally, the FDA would classify accessories in the same regulatory category as the parent device, especially when the accessory was included in the parent's premarket submission. However, this approach sometimes resulted in accessories being subject to unnecessarily stringent controls, regardless of their actual risk. For example, simple accessories with minimal risk could be regulated as Class II or III solely because of their association with a higher-risk parent device. In certain cases, FDA would issue a unique, separate classification regulation for the accessory, typically when the accessory could be used with multiple parent devices and/or had a different risk profile from the parent device (or devices) with which it was used.

The Food, Drug, and Cosmetic Act (FDCA) defines an “accessory” as a finished device intended to support, supplement, or augment another device's performance. This definition is distinct from that of a component, which is integral to the parent device's function. One of the most common challenges for manufacturers is accurately distinguishing between “accessories” and “components.” Accessories are typically marketed and regulated as separate products, even though they are designed to work with another device. In contrast, a component is an integral part of the parent device itself—something that is necessary for the device's basic function and is generally not intended to be marketed independently. For example, a blood pressure cuff sold separately for use with a monitor may be considered an accessory, while the internal wiring of the monitor would be classified as a component. Understanding this distinction is critical, as accessories may be eligible for independent classification based on their own risk profile, whereas components are regulated as part of the parent device. 

Recognizing the need for a more nuanced approach, the FDA Reauthorization Act of 2017 mandated that accessories be classified based on their own risks and the regulatory controls necessary to ensure safety and effectiveness, rather than by reference to the parent device's class. This legislative change was a pivotal moment, empowering FDA to reduce unnecessary regulatory burdens while maintaining robust safety standards. This shift laid the groundwork for FDA's current initiative to seek public input on reclassifying certain accessories into Class I, aiming to reduce regulatory burdens while maintaining safety standards.

In response to the 2017 legislation, FDA issued guidance in December 2017 entitled, Medical Device Accessories – Describing Accessories and Classification Pathways Guidance for Industry and Food and Drug Administration Staff. In that guidance document, FDA noted that the classification of accessory devices, as for non-accessory devices, should reflect the risks of the device when used as intended and the level of regulatory controls necessary to provide a reasonable assurance of safety and effectiveness. Recognizing that some accessories can have a lower risk profile than that of their parent device, the guidance provided examples of accessories meeting the statutory definition. The guidance also outlined the process for requesting accessory classification under section 513(f)(6) of the FDCA. All such requests are treated as Q-subs.  

FDA's current request for comment is a preliminary step in identifying existing accessories currently marketed under higher-class designations that might be suitable for distinct classification into Class I. “In such cases,” FDA notes in its request, “establishing a distinct classification for the accessory may reduce the regulatory burden associated with marketing the accessory without compromising the reasonable assurance of safety and effectiveness.”

Factors to consider in classification

FDA encourages commentors to address factors that influence whether accessories may be suitable for distinct classification into Class I. Factors tending to favor classification into Class I include:

• Risk profile. The accessory does not support or sustain human life and is not of substantial importance in preventing impairment of human health.
• Safety and effectiveness. The accessory does not pose an unreasonable risk of illness or injury when used as intended.
• Sufficiency of general controls. General controls alone (e.g., registration and listing, labeling requirements, device reporting) are sufficient to ensure the accessory’s safety and effectiveness.
• Design controls consideration. Design controls are unnecessary for reasonable assurance of safety and effectiveness, or, if such controls are necessary, they’ll remain applicable even if the accessory is moved into Class I (as would be the case for an accessory that’s automated with computer software).

Commenters hoping to persuade FDA should explain how general controls address an accessory’s specific risks and whether design controls are needed.

Beyond the core factors outlined by FDA—risk profile, safety and effectiveness, sufficiency of general controls, and design controls—companies can strengthen their submissions by addressing several additional considerations:

• Post-market safety data. Present evidence from complaint trends, medical device reports, and recalls, if any, that demonstrates the accessory’s safety when used as intended. Data showing low or well-contained risk can help substantiate a case for Class I classification.
• Clear use conditions. Explain how labeling, instructions for use, or other controls help prevent foreseeable misuse. If the accessory’s intended use is well-defined and mitigates risk, make this explicit in your comment.
• Comparative risk analysis. Articulate how the accessory’s hazards differ from those of the parent device, and why general controls are sufficient to address these risks. If the accessory is less risky than the parent device, clarify this distinction.
• Regulatory history. Reference prior 510(k), de novo, or other regulatory decisions for similar accessories that reflect a low risk profile. This can help FDA see precedent for reclassification.
• Operational and economic impact. Quantify how reclassification would reduce regulatory burden, such as shorter review cycles, more predictable pathways, or resource savings. If possible, provide specific, measurable impacts.
• Stakeholder impact. Consider how reclassification would benefit patients, providers, or healthcare systems—such as improved access, reduced friction in care delivery, or enhanced safety.
• International alignment. Stakeholders may wish to highlight how global regulatory frameworks, such as the EU MDR, approach accessory classification and encourage FDA to consider harmonization where risk profiles align.

By addressing these factors, companies can help FDA make informed, risk-based decisions that reflect real-world use and technical realities. Substantive, evidence-driven comments are far more likely to influence policy than those that simply list accessories without analysis. Comments that simply list existing accessories will carry less weight, according to FDA’s notice.

Manufacturers currently marketing accessories under higher-class designations should take advantage of FDA’s invitation. Now is the chance to influence FDA’s risk-based classification of not only specific accessories but entire categories of them, potentially translating into long-term regulatory relief. Robust comments can help ensure that FDA’s decisions are grounded in technical reality and practical use conditions, and not overly conservative assumptions about an accessory’s risks and necessary controls.

If you have questions or would like help preparing a comment, please contact one of the authors of this alert or the Hogan Lovells attorney with whom you normally work.

Authored by Jodi Scott and Mike Heyl