FDA De Novo Final Rule: New Regulations for Novel Medical Device Classification

In September 2025, the FDA published a final rule codifying the De Novo classification process in federal regulations for the first time since the pathway was created by the Food and Drug Administration Modernization Act of 1997. While the De Novo pathway has been available for nearly three decades, its procedural requirements were governed primarily by guidance documents rather than binding regulations. The final rule establishes enforceable timelines, clarifies submission content requirements, and defines the conditions under which FDA must accept, decline, or request additional information for a De Novo request.

What the Final Rule Establishes

The De Novo final rule addresses several procedural and substantive aspects of the classification process:

• 150-day review timeline: FDA must render a decision on a De Novo request within 150 calendar days of acceptance, creating an enforceable clock that did not previously exist in regulation
• Refuse to Accept criteria: The rule formalizes the grounds on which FDA may refuse to accept a De Novo request without substantive review, including missing required elements and inadequate device descriptions
• Proposed special controls: Applicants must propose specific special controls as part of the request, and FDA's decision will either adopt, modify, or reject those proposals
• Withdrawal and resubmission: The rule defines procedures for voluntary withdrawal and resubmission of De Novo requests, providing clarity that was previously handled informally

Impact on De Novo Submission Strategy

The formalization of De Novo requirements through binding regulation has practical implications for submission strategy. The 150-day review clock begins upon acceptance, making pre-submission meetings with FDA (Q-submissions) more valuable than ever as a mechanism for resolving substantive questions before the clock starts. Manufacturers should use pre-Sub meetings to align with FDA on the proposed device type name, the classification recommendation (Class I or Class II), and the proposed special controls before investing in the full submission package. A well-prepared pre-Sub can reduce the risk of FDA issuing an Additional Information (AI) request that tolls the review clock.

Special Controls Development

One of the most strategically important aspects of a De Novo request is the proposed special controls. Special controls are device-specific measures - such as performance testing standards, labeling requirements, and clinical data requirements - that, together with general controls, provide reasonable assurance of safety and effectiveness for the new device type. When FDA grants a De Novo request, the resulting classification order becomes the regulatory basis for subsequent 510(k) submissions for devices of the same type. This means that the special controls a De Novo applicant proposes will shape the regulatory requirements for competitors entering the same device category, giving De Novo applicants a first-mover influence on the regulatory landscape.

Preparing a Compliant De Novo Request Under the Final Rule

Under the final rule, a complete De Novo request must include a cover letter with the applicant's contact information and a representation that the device has not been classified or has been classified as Class III, a device description, the proposed device type name and classification, proposed special controls with supporting rationale, performance testing data, a benefit-risk analysis, and proposed labeling. Manufacturers should begin preparing De Novo requests against the final rule's content checklist rather than earlier guidance documents, as the rule supersedes prior guidance where conflicts exist. Sequence Group's regulatory team can assist with De Novo strategy development, pre-Sub preparation, and full submission compilation.