FDA De Novo Request Process: When and How to Use It

What De Novo Classification Is

The De Novo classification pathway was created by the Food and Drug Administration Modernization Act (FDAMA) of 1997 and significantly reformed by the FDA Safety and Innovation Act (FDASIA) of 2012. It provides a route to market for novel, low-to-moderate risk devices that have no legally marketed predicate device — meaning a traditional 510(k) is not available because no appropriate predicate exists.

Before De Novo, a device manufacturer with a genuinely novel device faced an unfavorable choice: attempt a 510(k) with a questionable predicate (risking a Not Substantially Equivalent determination), or file a Premarket Approval (PMA), which requires clinical trial evidence and is appropriate for high-risk Class III devices. Novel low-risk devices that fell into neither category were effectively blocked from the US market.

De Novo fills this gap. A successful De Novo request results in a Class II classification order for the device, with device-specific special controls that, in combination with general controls, provide reasonable assurance of safety and effectiveness. Once granted, a De Novo classification creates a new regulatory category — and that new category establishes the device as a legally marketed predicate for future 510(k) submissions by the original manufacturer or competitors.

This predicate-creating effect of De Novo authorization is strategically significant. Being the first company to receive De Novo authorization for a device type establishes a regulatory foothold that competitors must address. Your De Novo device becomes the benchmark against which future 510(k) filers for similar devices must demonstrate substantial equivalence.

When to Choose De Novo Over 510(k)

The fundamental criterion for De Novo eligibility is the absence of an appropriate predicate. If a predicate exists that shares your device's intended use and has the same or similar technological characteristics, 510(k) is typically the appropriate pathway. Choose De Novo when:

No appropriate predicate exists: Your device's intended use, mechanism of action, or technological characteristics are sufficiently novel that no cleared or pre-amendment device serves as an appropriate predicate. This can occur with genuinely new therapeutic modalities, novel diagnostic technologies, or devices that combine capabilities in ways that have no precedent.

After a Not Substantially Equivalent (NSE) determination: If you filed a 510(k) and received an NSE determination because FDA concluded the device raised new questions of safety and effectiveness, you can submit a De Novo request. The NSE is a prerequisite for this pathway. FDA must issue the NSE before you can submit De Novo via this route.

Direct De Novo: FDASIA authorized "direct De Novo" — submitting a De Novo request without a prior 510(k) submission when you determine from the outset that no appropriate predicate exists. Direct De Novo is often more efficient than filing a 510(k) you know will receive an NSE, because it avoids the 90-day 510(k) review cycle plus the time for an NSE determination.

When to avoid De Novo: Do not use De Novo for devices with clear predicates to avoid the 510(k) substantial equivalence analysis. FDA will reject a De Novo request if an appropriate predicate exists. Attempting De Novo to escape difficult performance data requirements for a 510(k) is a strategy that delays clearance rather than accelerating it.

De Novo Request Structure and Content

The De Novo request structure is defined by FDA's guidance on the De Novo classification process. Unlike a 510(k), which argues substantial equivalence to a predicate, a De Novo request argues that the device should be classified into Class II based on its risk profile and that proposed special controls, in combination with general controls, are sufficient to provide reasonable assurance of safety and effectiveness.

Device description: A thorough description of the device including intended use, indications for use, contraindications, principles of operation, technological features, and comparison to any similar devices (even if they are not appropriate predicates). For novel devices, the device description carries particular weight because FDA reviewers may not be familiar with the technology.

Proposed classification recommendation: Your De Novo request must explicitly propose Class II classification and articulate why the device does not warrant Class III classification (i.e., why general controls and special controls are sufficient, without PMA-level premarket evidence). This requires a risk analysis demonstrating that known risks are manageable with the proposed special controls.

Proposed special controls: This is the distinguishing element of a De Novo request. Special controls are the device-specific regulatory requirements that, in combination with general controls, provide reasonable assurance of safety and effectiveness for your device type. They become part of the classification order and apply to all future devices classified in the same category. Well-crafted special controls are specific enough to address the known risks of your device type but not so prescriptive that they unnecessarily constrain future innovation.

Performance data: De Novo requests require performance data — typically the same type of bench testing, clinical data (if applicable), and safety data that would support a 510(k). The evidentiary standard is based on your device's risk profile and what is necessary to demonstrate that special controls are sufficient.

The De Novo Review Process and Timeline

FDA's review process for De Novo requests has evolved significantly since the 2012 FDASIA reforms. Understanding the current process helps manage expectations and prepare appropriately.

Pre-De Novo Q-submission: Before filing a De Novo request, a Q-submission (pre-submission) meeting with FDA is strongly recommended. In the Q-submission, you can present your proposed special controls framework, performance data strategy, and classification rationale, and receive FDA feedback before investing in a full submission. FDA's written Q-submission response reduces uncertainty and frequently identifies issues that, if addressed in the full submission, prevent deficiencies and additional information requests.

De Novo review timeline: FDA's target review time for De Novo requests is 150 calendar days from acceptance. However, Additional Information (AI) requests — which are more common in De Novo reviews than in 510(k) reviews given the novelty of the devices — can substantially extend this timeline. Total time from De Novo submission to decision typically ranges from 10 to 24 months.

Acceptance review: Like 510(k)s, De Novo requests undergo an acceptance review before substantive review begins. FDA must accept the De Novo request before the 150-day clock starts. Submissions that are administratively incomplete will not be accepted.

Decision outcomes: A successful De Novo results in a classification order that establishes the device's product code, classification regulation, and special controls. The device is authorized for commercial distribution. An unsuccessful De Novo (if FDA determines Class II classification is insufficient) may result in a direction to file a PMA.