FDA Premarket Pathway Comparison
Three separate FDA premarket pathways govern how medical devices reach the US market. The right pathway is determined by device classification, risk profile, and whether a substantially equivalent predicate device exists. This page compares the three pathways across key decision factors — then routes you to the appropriate consulting service for your situation.
Side-by-Side Comparison
Decision Logic
Pathway determination is a regulatory analysis — not a lookup table. The steps below describe the typical sequence. If any step is uncertain, confirming the answer with FDA before investing in a full submission is almost always the right move.
Every FDA-regulated device maps to a three-letter FDA product code that determines its device type, classification regulation, and predicate pool. If the correct product code is uncertain — which is common for novel or combination devices — a Classification Determination Memo or 513(g) Request resolves it with or without FDA's written involvement. An incorrect product code at this step propagates errors through the entire strategy.
Class I devices present the lowest risk and are generally subject only to general controls; most are exempt from 510(k). Class II devices require special controls in addition to general controls — this is where the 510(k) pathway lives. Class III devices require PMA unless classified down to Class II via De Novo or a transitional regulation. Classification is determined by the product code's corresponding regulation at 21 CFR Part 862–892.
If your device is Class II and a substantially equivalent predicate exists in the FDA 510(k) database or as a legally marketed device, the 510(k) is the standard pathway. If no valid predicate exists — because the device is novel or differs in intended use or technological characteristics in a way that cannot be argued as equivalent — De Novo may be appropriate, provided the risk profile is low to moderate. A 510(k) gap assessment identifies whether a predicate strategy is viable and what equivalence gaps remain.
A Pre-Submission (Q-Sub) meeting with FDA is the mechanism for getting FDA's written feedback on your submission strategy before the submission is filed. For complex classification questions, a 513(g) Request obtains FDA's written classification information within 60 days. Neither action commits you to a pathway — they reduce the risk of investing in a submission strategy FDA may disagree with.
Key Distinctions
The three terms describe three distinct FDA market-authorization actions with different legal standards. Using them interchangeably is a common regulatory communication error that can create compliance exposure.
FDA determines the device is substantially equivalent to a legally marketed predicate. Cleared devices may be legally marketed in the US. FDA has not independently assessed the device's safety and effectiveness — it has determined the device is substantially equivalent to a device already on the market.
FDA finds that there is reasonable assurance that the device is safe and effective based on valid scientific evidence. PMA-approved devices may be legally marketed. The approval standard is higher and requires its own evidence base — not a comparison to a predicate.
FDA classifies the device into Class I or Class II, establishing Special Controls. De Novo is neither a clearance nor an approval — it is a classification action. Once classified, the device may be marketed, and the De Novo itself can serve as a predicate for future 510(k) submissions.
Using "approved" to describe a 510(k)-cleared device or a De Novo-classified device is a misstatement of FDA's action. This matters in labeling, marketing materials, and investor communications.
Common Questions
510(k) clearance and PMA approval are both FDA market-authorization actions, but the underlying legal standard is different. A 510(k) clears a device because FDA determines it is substantially equivalent to a legally marketed predicate device — the device does not require a finding of safety and effectiveness in isolation. PMA approval requires FDA to find that the device's safety and effectiveness has been established through valid scientific evidence, typically including clinical data from IDE-authorized trials. Cleared devices may be legally marketed; approved devices may be legally marketed. The distinction matters for the evidence package FDA requires.
De Novo is the pathway for novel Class II devices that are low to moderate risk but have no valid predicate device for a 510(k). If a device is low to moderate risk but FDA cannot clear it via 510(k) because no substantially equivalent predicate exists, and the device does not meet the risk threshold for PMA, De Novo may be appropriate. A successful De Novo creates a new device type and can itself become the predicate for future 510(k) submissions by the same or different manufacturers.
Many Class I and some Class II devices are exempt from 510(k) premarket notification. Exemption status is determined by the device's product code and classification regulation under 21 CFR Part 862–892. Exempt devices may still be subject to general controls, quality system requirements, and other regulations. The appropriate starting point is identifying the correct product code and reviewing the classification regulation for that code. A Classification Determination Memo or formal 513(g) request to FDA can confirm the classification when the product code is uncertain.
A 513(g) Request for Classification Information is a mechanism for asking FDA to provide written information on the classification of a device and the requirements that apply to it. It is appropriate when the product code is uncertain, when a novel device does not clearly fit an existing type, or when you need FDA's written position on classification before investing in a full 510(k), De Novo, or PMA. FDA responds within 60 days. The written response is a useful starting point for pathway planning, though it is not a clearance or approval action.
Yes. An NSE determination for a 510(k) is one basis for a De Novo request. If FDA finds a device not substantially equivalent because no valid predicate exists and the device is low to moderate risk, the sponsor may request De Novo classification. This is one of two De Novo pathways — the other is a direct De Novo submission without a preceding 510(k) for devices that the sponsor determines from the outset have no valid predicate.
FDA performance goals vary by submission type and fiscal year. Historically, standard 510(k) reviews target a 90-day review clock under MDUFA goals; the actual time to a clearance decision depends on whether FDA issues additional information or deficiency requests. PMA review targets 180 days for a Panel Track PMA. De Novo review historically takes 12 months or longer. These are FDA review goals, not guarantees — actual timelines depend on submission quality, device complexity, and FDA capacity.
Next Step
If you have read this page and still have a pathway question specific to your device, a free 30-minute scope call is the fastest way to get a directional answer. If the pathway is identified and the 510(k) is the correct route, the gap assessment is the right starting point.
Predicate review, substantial equivalence gap analysis, testing-gap matrix, and written submission roadmap. $4,950 flat fee. 100% credited toward Full Submission Package Preparation within 90 days.
Start the Gap AssessmentIf the product code, device class, or predicate strategy is uncertain, a Classification Determination Memo or formal 513(g) Request to FDA resolves it. Published flat-fee pricing for both options.
See 513(g) PricingUnsure which service applies to your device? A free 30-minute call is the fastest way to identify the right starting point — with no obligation to proceed.
Book Free Scope CallFDA's formal mechanism for getting written feedback on your submission strategy before the submission is filed. $4,500 flat fee, standalone or paired with the gap assessment.
Start Q-Sub PreparationQuestions?
A free 30-minute scope call is the fastest way to determine which pathway applies and which service is the right first step for your device.