FDA De Novo Classification

De Novo classification is the FDA pathway for authorizing a novel, low-to-moderate-risk medical device for which general controls alone, or general and special controls, would provide a reasonable assurance of safety and effectiveness, but for which no legally marketed predicate device exists to support a 510(k) substantial-equivalence claim. It is provided for at Section 513(f)(2) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. §360c(f)(2)).

Last verified August 25, 2026 against the statutory text at 21 U.S.C. §360c(f)(2) and FDA’s De Novo Classification Process final rule (2021).

Why De Novo Exists

Under the FD&C Act’s default classification scheme, a new device without an existing predicate is automatically classified into Class III — the highest-risk tier, which normally requires a Premarket Approval (PMA) application, FDA’s most burdensome pathway. De Novo classification exists to correct for cases where that automatic Class III placement is not warranted by the device’s actual risk profile: a genuinely novel device can still be low-to-moderate risk even though nothing like it has been legally marketed before.

Two Ways Into De Novo

• Post-NSE route (original, 1997). A sponsor first submits a 510(k). If FDA determines the device is Not Substantially Equivalent (NSE) to any existing predicate — which would otherwise place it in Class III by default — the sponsor can then request De Novo classification.
• Direct De Novo (2012 onward). Section 607 of the Food and Drug Administration Safety and Innovation Act (FDASIA) amended Section 513(f)(2) to let a sponsor request De Novo classification directly, in lieu of first filing a 510(k) and waiting for an NSE determination. The direct route is now the dominant one in practice; the original post-NSE route is comparatively rare.

The 21st Century Cures Act (2016) further removed an earlier requirement that a post-NSE De Novo request be filed within 30 days of the NSE determination, and clarified that a granted De Novo classification can itself serve as a predicate for later devices with the same technological characteristics submitted through the ordinary 510(k) pathway.

What a Request Must Show

A De Novo request must include a complete discussion of why general controls alone, or general and special controls, provide a reasonable assurance of safety and effectiveness for the device’s intended use — and, if the sponsor is proposing Class II, exactly what special controls (for example, specific performance testing, labeling requirements, or postmarket surveillance) would support that reasonable assurance. FDA reviews the request against the same statutory risk criteria used for any device classification decision (Section 513(a)(1)) and, per the 2021 final rule implementing the pathway’s current procedures, issues a written order classifying the device.

Timeline

FDA has 120 days from receipt of a complete De Novo request to issue a classification order. As with other FDA device pathways, requests for additional information can pause the clock; a sponsor can also withdraw a pending request.

Outcome and Downstream Effect

A granted De Novo request establishes a brand-new device classification — Class I or Class II — along with any special controls FDA determines apply. Because that classification becomes the “initial classification” for that device type, it functions as a new predicate: subsequent devices with the same intended use and technological characteristics can cite it in their own 510(k) submissions instead of needing their own De Novo request. This predicate-creating effect is one reason De Novo classification is closely watched in fast-moving device categories — the first successful De Novo request in a novel product area effectively opens a 510(k) route for everyone who follows.

De Novo vs. 510(k) vs. PMA

	De Novo	510(k)	PMA
Predicate required?	No — that’s the point of the pathway	Yes, a legally marketed predicate	No, but requires full safety/effectiveness evidence
Resulting class	New Class I or Class II classification	Class I or II (matching the predicate)	Class III
FDA decision clock	120 days	90 days (MDUFA goal)	180 days (MDUFA goal), often longer in practice
Statutory basis	Section 513(f)(2)	Section 510(k)	Section 515

See the 510(k) vs. PMA comparison for the more common fork in the device pathway decision, and Breakthrough Device Designation for the expedited-review status that can be layered onto a De Novo submission for a qualifying device.

Why This Matters for Research Administration

A device moving through De Novo classification, rather than 510(k), signals to research administrators that no comparable device or established clinical-use pattern exists yet — which typically means less institutional or IRB precedent to draw on when reviewing the associated investigational protocol, and a higher chance the study is generating the very safety and performance data FDA will rely on for the classification decision itself.

Frequently Asked Questions

What is the difference between De Novo and 510(k)?

510(k) requires showing substantial equivalence to an existing, legally marketed predicate device. De Novo is used specifically when no such predicate exists, and results in a brand-new device classification rather than a comparison to an existing one.

Can a sponsor go straight to De Novo without filing a 510(k) first?

Yes. Since FDASIA’s 2012 amendment, a sponsor can request De Novo classification directly (“direct De Novo”) without first submitting a 510(k) and receiving a Not Substantially Equivalent determination.

How long does FDA take to decide a De Novo request?

FDA has 120 days from receipt of a complete request to issue a written classification order.

Does a granted De Novo classification become a predicate for future devices?

Yes. Under the 21st Century Cures Act, a device classified through De Novo can serve as a predicate for later 510(k) submissions from other sponsors for devices with the same intended use and technological characteristics.

References

• 21 U.S.C. §360c(f)(2) (FD&C Act Section 513(f)(2)), via GovInfo, U.S. Code.
• Food and Drug Administration Safety and Innovation Act (FDASIA), Pub. L. No. 112-144, §607 (2012).
• 21st Century Cures Act, Pub. L. No. 114-255 (2016).
• “Medical Device De Novo Classification Process,” Final Rule, Federal Register (October 5, 2021).