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  3. Device Advice: Comprehensive Regulatory Assistance
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  5. Premarket Submissions: Selecting and Preparing the Correct Submission
  6. Premarket Notification 510(k)
  7. How to Find and Effectively Use Predicate Devices
  1. Premarket Notification 510(k)

How to Find and Effectively Use Predicate Devices

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A Premarket Notification [510(k)] is a premarketing submission made to FDA to demonstrate that the device to be marketed is safe and effective by proving substantial equivalence (SE) to a legally marketed device (predicate device) that is not subject to Premarket Approval (PMA). Submitters must compare their 510(k) device to a similar legally marketed U.S. device(s). A device recently cleared under 510(k) is usually used as a predicate device. However, any legally U.S. marketed device may be used as a predicate. This includes: a device that has been cleared through the 510(k) process; a device that was legally marketed prior to May 28, 1976 (preamendments device); a device that was originally on the U.S. market as a Class III device (Premarket Approval) and later downclassified to Class II or I; or a 510(k) exempt device.

The legally marketed device(s) to which equivalence is drawn is known as the predicate device(s). A claim of substantial equivalence does not mean the device(s) must be identical. Substantial equivalence is established with respect to: intended use, design, energy used or delivered, materials, performance, safety, effectiveness, labeling, biocompatibility, standards, and other applicable characteristics. You can claim SE to either a preamendments or postamendments device that is or was legally marketed. Legally marketed means that the predicate cannot be one that is or was in violation of the Federal Food Drug & Cosmetic (FD&C) Act. An applicant may claim SE to a device that is no longer being marketed in the U.S.

Postamendments Device

Postamendment devices are medical devices marketed after May 28, 1976. Because medical technology has changed greatly since 1976, almost all 510(k) submissions claim substantial equivalence to a postamendment device that has been recently cleared under the 510(k) process.

Preamendments Device

The term "preamendments device" refers to devices legally marketed in the U.S. by a firm before May 28, 1976 and which have not been:

  • significantly changed or modified since then; and
  • for which a regulation requiring a premarket approval (PMA) application has not been published by FDA.

Devices meeting the above criteria are referred to as "grandfathered" devices and do not require a 510(k). The device must have the same intended use as that marketed before May 28, 1976. If the device is labeled for a new intended use, then the device is considered a new device and a 510(k) must be submitted to FDA for marketing clearance.

In order for a firm to claim that it has a preamendments device, it must demonstrate that its device was labeled, promoted, and distributed in interstate commerce for a specific intended use and that intended use has not changed.

If you use a preamendment device as your predicate device, you may need to provide documentation that it meets the preamendment status criteria. Preamendment devices will not have a 510(k) number since preamendment devices were grandfathered from 510(k) review. Since medical science has advanced greatly since 1976, it is recommended that you use a recently cleared device under 510(k) as your predicate device.

How to Search for a Predicate Device

The FDA 510(k) database contains all devices cleared under the 510(k) process. The FDA databases on the web are updated on or around the 5th of every month. The classification of the device and product code is essential in searching for predicate devices. Classification of your device can be found by performing a search on the Product Code Classification Database. The classification database will provide the classification panel (e.g., orthopedic devices), common name, product code, and CFR regulation, if your device type has received final classification by FDA (e.g., 21 CFR 888.1100, arthroscope). Additional information on classification and product codes can be found in "Classify Your Medical Device."

Information which can be useful to find a predicate device includes:

  • names of similar devices - traded name under which the device is marketed;
  • manufacturer(s) of the similar device(s);
  • marketing status, i.e., preamendments or postamendments device;
  • 510(k) numbers for postamendments devices;
  • classification information, i.e., product codes, classifying regulations, etc., for your device.

Once you have found the classification of your device, you should begin your search in the 510(k) database.
You may have to try several ways of searching the database. It is usually best to complete only one box in the online search form per search. The search engine searches for an exact match of text. Therefore, one descriptive word in the "device name" box is recommended.

FDA assigns a unique 3-letter product code or "procode" for each generic category of device, whether it has been formally classified by FDA or not. Only FDA generated product codes will work with the 510(k) and other FDA databases. 510(k)s for similar device types are usually linked in the 510(k) database by the same product code. While this is not always true, it is the case with enough regularity that searching for predicate devices by product code is usually the most effective (leaving the other boxes blank). Alternatively, if you know the manufacturer name(s) for a similar device, you may search the database by manufacturer name. Hyphens or spaces in names can make a difference, so try different combinations of the manufacturer's name if the search results in "no records found." Please note that the 510(k) database contains original application information only. That is, the 510(k) database maintains the name of the original applicant and the original trade name provided in the 510(k). It is not updated to reflect the current owner or distributor of the product nor any changes in trade name.

510(k) Search Engine

How to Effectively Use Predicate Devices

Manufacturers must identify a primary predicate device which is most similar to the device under review with respect to indications for use and technological characteristics. Manufacturers may identify more than one predicate device to help demonstrate substantial equivalence in certain circumstances. The use of split predicates is inconsistent with the 510(k) regulatory standard. Manufacturers may identify “reference devices” within their 510(k) to support scientific methodology or standard reference values.

For more information on how to effectively use predicate devices, please refer to The 510(k) Program: Evaluating Substantial Equivalence in Premarket Notification [510(k)].

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