Is Your Medical Device a Well-Established Technology (WET)?

As guidance committees, manufacturers, and notified bodies continue to interpret the EU MDR, some areas remain fuzzy. Well-established technology (WET) is high on the list of definitions that are disputed as notified bodies seem to have a different interpretation than the guidance document. This puts manufacturers in the difficult position of having to decide whether a device is a WET and defending that stance to notified bodies.

What is a well-established technology under MDR?

The term “well-established technology” is used in Article 52(5) and Article 61(8) of the MDR, but unfortunately, no clear definition is provided. In both articles, these devices are referred to in association with “exempted” devices. Article 61(6b) includes a list of exempted devices, but the language in the regulation also states that the term is not restricted to only those devices listed and can also include similar devices. The list of exempted devices in MDR are all Class III or implantable devices, including:

“...sutures, staples, dental fillings, dental braces, tooth crowns, screws, wedges, plates, wires, pins, clips or connectors for which the clinical evaluation is based on sufficient clinical data and is in compliance with the relevant product-specific CS (common specifications), where such a CS is available.”

Notably, the regulation also states, “Where justified in view of well-established technologies, similar to those used in the exempted devices listed in point (b) of paragraph 6 of this Article ...” the commission is empowered to add other types of class III or implantable devices.

Article 52(5) and 61(8) seem to indicate that devices that are WET are similar to exempted devices but not the same thing. Specifically:

“Where justified in view of well-established technologies, similar to those used in the exempted devices listed in the second subparagraph of paragraph 4 of this Article, being used in other class IIb implantable devices, or where justified in order to protect the health and safety of patients, users or other persons or other aspects of public health, the Commission is empowered to adopt delegated acts in accordance with Article 115 to amend that list by adding other types of class IIb implantable devices to that list or removing devices therefrom.”

Therefore, it seems like the commission is the only group that is empowered to add to the “exempted” device list, but it is not clear whether this also applies to devices that are WET. 

How does the guidance document define a well-established technology?

The MDCG 2020-6 Guidance on sufficient clinical evidence for legacy devices provides a definition and further details around sufficient clinical evidence for WET devices. The guidance document attempts to provide clarity with its definition:

“‘well-established technology’: this terminology is used in Article 52(5) and Article 61(8) of the MDR, but is not defined in these articles. The term is not restricted to the devices listed in Article 61(6b); Article 61(8) explicitly states that this includes devices similar to the exempted devices listed in Article 61(6b), which might be added to that list in future. The common features of the devices which are well-established technologies are that they all have:

• • relatively simple, common and stable designs with little evolution;
  • their generic device group has well-known safety and has not been associated with safety issues in the past;
  • well-known clinical performance characteristics and their generic device group are standard of care devices where there is little evolution in indications and the state of the art;
  • a long history on the market.

Therefore, any devices that meet all these criteria may be considered ‘well-established technologies.’”

While the guidance does not explicitly define non-WET technologies, the definition is assumed based on the definition of WET technologies. MDCG 2020-6 also refers to the “exempted” devices listed in 61(b) as a specific subset of well-established technologies, suggesting that other devices may be considered WET. Therefore, MDCG 2020-6 seems to enable other devices (including implantable, class III, and lower-risk devices) to be considered WET and does not limit the definition to technologies that are similar to the exempted devices listed in the MDR section 61(6b). This opens the door for manufacturers to claim that a broader range of devices are WET.   

What are the benefits of having a well-established technology?

Why is the definition of a WET so important? Having a device designated as a WET could save you a lot of time and resources. As defined in EU MDR Article 52(5), “exempted” class IIb implantable devices do not require a clinical investigation and do not require the technical documentation to be assessed for every device. 

Another important impact on the clinical evaluation for WET devices, at least according to MDCG 2020-6, is that unlike non-WET devices, which require clinical data on the device under evaluation or an equivalent device, WET devices may be able to, “confirm conformity with the relevant GSPRs via an evaluation of cumulative evidence from additional sources,” such as nonclinical testing, compliance to standards, and data from similar devices. 

It’s important to note, however, that the clinical evaluation always needs to be based on sufficient clinical evidence. Using nonclinical testing data and data from similar devices is particularly important since reliance solely on complaints and vigilance data is not typically sufficient under the MDR, so other ways of demonstrating conformity are important.

How are notified bodies interpreting the definition?

We have seen that notified bodies are interpreting the definition of WET differently than the criteria outlined in the guidance document in favor of a more rigid definition that only includes the device types listed in Article 61(6b). This eliminates the possibility of establishing other devices as WET. 

Importantly, notified bodies are also not allowing manufacturers to claim that a similar device should be considered WET because they interpret the regulation to mean that only the commission can amend the list. This is both confusing and frustrating for manufacturers.

What are some common challenges manufacturers face around WET?

Because there is a clear advantage to having a device that is considered WET—saving time and money by not having to do a clinical investigation—many manufacturers are trying to get their devices qualified as such. The lack of clarity around the definition is a significant issue, but even with clear guidance, many manufacturers are submitting devices that do not meet all four of the criteria outlined in the MDCG document. Many manufacturers are only focusing on the length of time a device has been on the market and not considering all four features of WET devices listed in MDCG 2020-6. 

For example, the first feature is that the devices are relatively simple, common, and stable designs with little evolution. Therefore, a complex device that has been on the market may not be considered WET since it is not “simple.” The list of non-WET devices included in the Joint NB-Position Paper on Spinal Classification per the MDR exemplifies this since devices with “multiple components or complex wedges, spacers, pins and screws (e.g. expandable)” are not considered WET. On the other hand, a device like a guide wire would likely meet all four criteria, even though it is not on the list of exempted devices.

We have also seen that many manufacturers do not present enough data to justify safety and performance when trying to claim their device is a WET. When it comes to providing data, reliance solely on complaints and vigilance is not sufficient.

What are some tips for manufacturers with well-established technologies?

If you think you have a WET, depending on the amount of information that has already been gathered for the device under evaluation, it may be worth making the effort to justify this to your notified body, and following these tips could help. 

Communicate with your notified body. 

Although it’s not possible to control how the notified bodies interpret the regulations and the guidance, manufacturers can make an effort to claim their device is a WET. If possible, discuss the topic with your notified body to understand what factors and definitions they use to identify WET and non-WET devices.

Provide high-quality technical documentation. 

Regardless of whether your device is technically considered WET, tell the best story you can in your clinical evaluation based on the available scientific evidence. Write your CER the way you normally would, regardless of whether you’re calling your device a WET or not. Make the best argument for your device and understand that you still might have to provide clinical evidence. In some cases, this may include highlighting nonclinical testing, compliance with standards, and the performance and safety of similar devices alongside any clinical data you may have for the device under evaluation and equivalent device, as applicable. 

If you are trying to establish your device as WET, make sure you provide clear justification in your clinical evaluation based on the definition in the EU MDR. If you think this may be an issue, consider collecting some relevant clinical data on your devices through post-market clinical follow-up (PMCF). This may reduce the risk of nonconformities to your MDR application. It’s important, however, that the data collected through PMCF is directly applicable to the safety and performance of your devices and addresses gaps in knowledge about safety and performance, including providing data relevant to the specific and measurable outcomes.

Evaluate whether equivalence is an option. 

Although it has been difficult to demonstrate equivalence recently, it may be worth at least reconsidering this approach, particularly for lower-risk devices. It’s important to keep in mind, however, that as stated in MDCG 2020-6, “considerations of equivalence shall be based on proper scientific justification.” The manufacturer needs to be able to “demonstrate sufficient levels of access to the data” relating to the equivalent device. In short, the device should actually be equivalent, and you should have sufficient information to make this argument. MDCG 2020-5 outlines details of the demonstration of equivalence.

Closely follow provided guidance. 

Although some notified bodies are ignoring the guidance in MDCG 2020-6 in favor of a more stringent approach, it is still a best practice to closely follow the guidance when making the argument for a WET. Provide clear justification for each of the four points in the guidance because your interpretation of the guidance may vary from the notified bodies. Each point should be given its due diligence and the importance of no single point should be downplayed. 

Provide sufficient data from other sources. 

Having a WET device enables you to rely on other data sources to show that you have sufficient clinical evidence for your device. Otherwise, you need data specifically on your device or an equivalent device. Include an evaluation of cumulative evidence from additional sources, including:

• Evaluation of state of the art, including evaluation of clinical data from similar devices 
• Simulated use/animal/cadaveric testing involving healthcare professionals or other end users
• Pre-clinical and bench testing/compliance to standards

How can RQM+ help?

Our team lives and breathes EU MDR. With former notified body leadership in the mix, we have a strong understanding of what reviewers look for in all types of submissions. We can help you evaluate the likelihood of your device being considered a WET, write a high-quality CER, and provide a justification that aligns with the guidance. 

If you want to be able to quickly find references to WET or any other term in the regulation, download our free MDR Filtering Tool today.