A de Novo is a classification process using a risk-based strategy for new, novel devices that have not been classified as of yet. The new ruling in 2014 streamlined the process by creating an alternative pathway that does not require submission of a 510k prior to a de novo request. Prior to this ruling, companies would have to submit a 510k, FDA would review it, and if they determined that the device had no substantial equivalent, they would automatically classify it as Class III, and the company would have to submit a de-novo application to try to have it down classified. Now companies can go directly to a de-novo application.

I think this new ruling makes sense, because the old process appeared to be extremely cumbersome and time consuming. For companies who are developing novel devices that do not have a predicate and that they believe should receive a Class I or Class II designation, this seems like an attractive regulatory route.

References:
https://www.fda.gov/downloads/training/cdrhlearn/ucm421766.pdf
https://www.meddeviceonline.com/doc/secrets-of-the-de-novo-pathway-part-why-aren-t-more-device-makers-using-it-0001

@Srg36 did a great job of summarizing the de Novo classification process and ruling. I agree that this deNovo classification process is beneficial because previously having an automatic Class III determination and to submit to have down classed to Class I or II is inefficient. Having the deNovo process is both time and money saving for both the FDA and company submitting. It's also helpful that the class I or class II through the de novo process may be marketed and used as predicates for future premarket notifications. This way manufacturers can look at the de novo decisionsummary as a resource with the information necessary to support substantial equivalence for devices that they may wish to use the device as a predicate.

Adding to @srg36, De Novo means an application sent by the medical device sponsor to FDA. So it establishes a new "device type" along with classification, regulation, necessary controls and product code, and it is eligible to serve as a predicate for new medical devices, where appropriate 510k process. So instead of going through 510k process there is 2 alternative pathways: 510k to de novo, where you attempt 510k route with proposed predicate device and submission found NSE, but candidate for de novo; or direct de novo, it is useful if you believe proposed device is viable de novo candidate. During the 510k to de novo, sponsor submits 510k, FDA reviews 510k submission and makes NSE finding due to lack of predicate, then sponsor submits de novo application, finally FDS reviews de novo application. On the other hand, during direct de novo, sponsor submits de novo application, then FDA reviews it.
In my opinion, this makes much more sense. It saves time for the companies that have an important product that needs to be released. So now companies don't have to wait for the 510K and just skips right to the de novo application.

According to the FDA update from November 2014, the de novo is a sorting process that categorizes novel devices based on risk strategy. It is similar to the regulatory structure that we identify with in terms of class I, II or III. Based on the medical device amendment of 1976 the medical device classification will result in certain controls and documentation. Such as the premarket approval for class III devices. The de novo is also known as “evaluation of automatic class III designation.” In 2012 the process was changed to exempt a 510 k submission prior to the de novo request with a set 120 FDA day review.
De Novo is first approached when an application is sent from the medical device company to the FDA.

The two outcomes of submitting this application are:
1. Classify the new medical device along with the controls and product code
2. If the device is similar to previous devices then a 510 K will need to be completed

The process has two submission pathways:
1. Complete a 510 k then complete a de novo
2. Complete a de novo directly

If a de novo is granted then the new device is legally marketed and the establishment of a new classification regulation must be completed.

References:
https://www.fda.gov/downloads/training/cdrhlearn/ucm421766.pdf
https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/Overview/GeneralandSpecialControls/default.htm

A de Novo approach is efficient in getting the approval from the FDA and launching the products in the market rapidly. It’s used for new devices that has not been previously classified by the FDA. FDA uses a risk-based strategy to classify the device into Class I or II. New ruling of de novo process has streamlined the entire process by making it easier for the medical device sponsor to get an approval without the submission of 510k approval. If the de Novo application is granted, then it establishes a new device with the necessary controls and classification regulation. Also, the device is eligible to be marketed and used as predicate for future medical devices and 510k approval. All in all, this new ruling of the de novo 510k process make it efficient for the sponsor and the future company to release and market the product.

The de Novo 510K process is classification procedure to classify the new medical devices which are not previously classified. The new rule has made the process easy by getting approval without the submission of 510K approval. An application is sent to the FDA, FDA evaluated the risk possessed by the device and classifies it into Class 1,2 or 3 medical device. Along with classification it establishes new regulation, necessary controls and product code. It can act as a predicate for a new medical device. The new rule is more efficient in releasing and marketing a novel device on time without delay (less time consumption).

The de Novo 510K allows that a device does not have to be evaluated by the 510K and discovered NSE beforehand. This means that someone can submit a de Novo without submitting a 510K prior to it, if they find that their device can be categorized as Class I or Class II, and no marketed predicate device is present. With the de Novo, a person can ask for the FDA to classify the device. The de Novo process is useful in that it allows for companies to bring in their products at a better pace if there is only low risk. The main disadvantage of the process is making sure to understand the amount of risk the product might actually have. I feel that the de Novo 510K process is a good way to go with new products only if someone is sure there is a low risk factor and there is no predicate device.

References:
https://www.fda.gov/downloads/medicaldevices/deviceregulationandguidance/guidancedocuments/ucm273903.pdf

De Novo is a classification process which uses a risk based strategy for new novel devices whose types has not previously been classified. It can be used for devices that would have been classified into Class III to allow them to be classified into Class I or II. For the De Novo process an application must be sent to the FDA, and if it is granted would establish a new “device type” along with classification, regulation, and necessary controls and product code.
A 510(k) submission is not needed before a device is submitted for the De Novo application process. However pre-submissions are strongly recommended prior to the submission of de novo, especially devices that have not been previously reviewed under a 510(k).
In my opinion it is good to have a process like De Novo which allows a certain amount of flexibility to the classification process and does not require additional unnecessary regulations on medical devices that are not needed. By being able to be flexible on medical device classifications, it allows medical devices companies to be able to develop and release products faster for products that would have been rigidly classified into a high medical device class. Using a risk based approach for the classification is the best way to do this in my opinion as it maintains the integrity of the safety for the end users of all medical devices which are sold.

De novo classification (513(f)(2) of the Federal Food, Drug, and cosmetic act) provides a pathway to Class I or Class II classification for medical devices for which general controls or general and special controls provide a reasonable assurance of safety and effectiveness, bur for which there is no legally marketed predicate device.
https://www.fda.gov/downloads/medicaldevices/deviceregulationandguidance/guidancedocuments/ucm273903.pdf
When a completely new device is introduced to the market it is automatically classified as a Class III in the US. If the device is not considered a high risk you may use the FDA process known as “de Novo”. The “de novo” submission will have the FDA review your submission through means of 5139(g) or Pre-submission. It the FDA determines that your device is a “novel” with no existing classification or predicate device the FDA may classify your device as a Class I or Class II and may issue an entirely new product code and regulation number. Just keep in mind you cannot submit a de Novo and a 510(k) at the same time. The FDA searches its database upon receipt of a de novo submission. If the FDA determines that you have submitted your device for review under a 510(k) for the same intended use, your de novo submission will be rejected
https://www.emergogroup.com/services/united-states/fda-device-classification
The new ruling is actually a game changer compared to the old process. It seems the old process used to force you to take a certain path even if your device was not a high risk one. The de novo process will enable companies bring more innovative low risk products to market and can establish limited barriers to entry for competitors
https://www.morganlewis.com/-/media/files/publication/presentation/webinar/2017/fda_de-novo-pathway_9march17.ashx

De Novo classification process involves new, novice unclassified devices using a risk based strategy to determine their class; class I, II or III. An application drafted by Medical Device Sponsor is sent to FDA to determine device type along with classification, regulation, necessary controls and product code if accepted.

De Novo 510K is the submission process of 510k by manufacturer, reviewed by FDA for lack of predicates. Sponsor also submit De Novo to be regulated for lack of evidence to demonstrate safety and effectiveness of new device. And reviewed by FDA for application acknowledgement or rejection.

Under regulatory structure, De Novo fits under Premarket Notification 510(k) which demostrate to be a predicate device and CDRH Class 1,2.

“De Novo” pathway- Established by the Food and Drug Administration Modernization Act of 1997 to provide a new mechanism for reclassification of certain lower risk devices from class Ⅲ to class ⅠorⅡ.
Examples of De Novos Granted for Devices Presentng More Than Low Risk
De novo pathway is not just for low risk devices—
1. Neurovascular mechanical thrombectomy device for acute ischemic stroke
2. High intensity ultrasound for prostate tissue ablation
3. Assay for determination of procalcitonin in serum/plasma to aid in assessment of patients with suspected sepsis.
4. Esophageal thermal regulation device.

FDA uses de novo system to classify medical devices as class I, class II, class III based on increasing risk to patient or user. The new devices are considered class III in the US, devices that are innovative sometime their exact predicate device is difficult to find so 'Request for information ' that would outline characteristics of device would submitted to FDA called 513(g) submission . If FDA through 513(g) states that device has no existing classification or predicate device on market ,we can file "de novo" submission after that FDA will decide if device is entirely new, class I ,class II and issue regulation number .Device remains in class III if it is rejected It helps to determine proper classification and regulatory requirement for medical devices. The "de novo" process is intended to improve efficiency of bringing low risk medical device to market that was classified as class III due to absence of predicate devices through a simple reclassification of devices. Now, manufacturer no longer need to submit 510(K) and wait for decision of NSE. Before "de novo" manufacturer have no other option to PMA if no predicate exist . PMA is lengthy and costly. If device is novel , presenting medium or low risk profile and no predicates exists de novo is the right option.

When the De Novo process was first initiated, sponsors needed to submit the premarket notification (510(k)), to which the FDA would issue final 510(k) decision of “not substantially equivalent” due to no predicate. The sponsor would then need to submit A De Novo request and the FDA would decide whether to classify device from Class III to Class I or II with new classification/regulation. The revision of 2014 allowed alternative pathway that doesn’t require submission of a 510(k) prior to de novo request limiting the timeframe for review set at 120 FDA days. This revision of the De Novo process is highly attractive because it is less cumbersome and time-consuming. It provides companies with a direct regulatory pathway toward a Class I or Class II designation.

The de Novo pathway was introduced to address novel devices without a predicate device, for low to moderate risk devices. After the submission of the de Novo the FDA reviews the device and adjusts it in the required classification of medical devices and sets any regulations if needed. The FDA also looks for any special requirements for premarket approval that might be needed as the device may act as a 'substantially equivalent device' in the future for any new device with the same function.

de-Novo 510(k) is when the company submits an application for 510(k) approval, but receives  a "not substantially equivalent" response from the FDA and post that the company will submit the de-Novo request, secondly, the device being novel the company will right away submit a de-Novo request to the FDA prior to submitting the 510(k) request.

The de-Novo process is a good choice for novel devices with low-moderate risks as this will not determine them into the class III group as is done with new devices without a predicate device. This will reduce the amount of work involved in filing a PMA if the company fails to convince the FDA that the device is not risky and will reduce also the trouble of gathering clinical data from clinical trials, will save a lot of money and also time by reducing the amount of extra documentation needed for class III as compared to that of class I and II devices.  It fits into the regulatory structure the same way as any new device with/without predicate device would be involved.