When Can I Use a Second 510k Predicate?

This article describes when you can use a second 510k predicate for demonstrating the substantial equivalence of your subject device in a 510k submission.

Recently a client questioned me about the use of a secondary predicate in a 510k submission that I was preparing. They were under the impression that only one predicate was allowed for a 510k submission because the FDA considers the two predicate devices to be a “split predicate.”  About half of the 510k submissions I helped prepare in the past year have used a secondary predicate, and all of the submissions have been cleared so far. When is a second 510k predicate allowed?

The FDA released a new guidance document that explains how to demonstrate substantial equivalence. The guidance document includes a new decision tree that summarizes each of the six questions that 510k reviewers are required to answer in the process of evaluating your 510k submission for substantial equivalence. The evidence of substantial equivalence must be summarized in Section 12 of your submission, and the guidance document reviews the content that should be provided.

Substantial equivalence is evaluated against a predicate device or multiple predicates. To be considered substantially equivalent, the subject device of your 510k submission must have the same intended use AND the same technological characteristics as the predicate device. Therefore, you cannot use two different predicates if one predicate has the same intended use (but different technological characteristics), and the second predicate has the same technological characteristics (but a different intended use). This does not prohibit you from using a secondary predicate, but you must meet the requirements of this guidance document to receive 510k clearance. The guidance document reviews five examples of multiple predicates being used correctly to demonstrate substantial equivalence.

When you are trying to use multiple predicate devices to demonstrate substantial equivalence to your subject device in a 510k submission, you have three options for the correct use of multiple predicate devices:

1. Two predicates with different technological characteristics, but the same intended use.
2. A device with more than one intended use.
3. A device with more than one indication under the same intended use.

If you use “option 1”, then your subject device must have the technological characteristics of both predicate devices. For example, your device has Bluetooth capability, and it uses infrared technology to measure temperature, while one of the two predicates has Bluetooth but uses a thermistor, and the other predicate uses infrared measurement but does not have Bluetooth.

If you use “option 2”, you are combining the features of two different devices into one device. For example, one predicate device is used to measure temperature, and the other predicate device is used to measure blood pressure. Your device, however, can perform both functions. You might have chosen another multi-parameter monitor on the market as your predicate, however, you may not be able to do that if none of the multi-parameter monitors have the same combination of intended uses and technological characteristics. This scenario is quite common when a new technology is introduced for monitoring, and none of the multi-parameter monitors are using the new technology yet.

If you use “option 3”, you need to be careful that the ability of your subject device to be used for a second indication does not compromise the performance of the device for the first indication. For example, bone fixation plates are designed for fixation of bone fractures. If the first indication is for long bones, and the second indication is for small bones in the wrist, the size and strength of the bone fixation plate may not be adequate for long bones, or the device may be too large for the wrist.

If you would like to learn more about demonstrating substantial equivalence, please join us for a live webinar during Thursday’s Learning Lunch. To register for the webinar, please visit the following webpage.