REHYB@ÖSSUR: Get the paperwork done

10.10.2022. Many research projects in the medical device field result in a device prototype at some point in the project with the intention of testing with end users, but when is a prototype ready for such testing? The short answer is that it needs to be safe both for the user and others that are around the device during testing. For a non-CE marked investigational device, two key approvals need to be obtained. First, the planned protocol needs to get approval from the relevant ethical board and then the investigational device needs to be approved by a so-called Competent Authority (CA) of the country where tests will be performed.

To assess the device the CA needs to understand the technology and convince themselves that the device is built with safety of the user in focus. To promote this understanding, a technical file for the prototype has to be created and submitted as part of documentation for getting approval for an investigational medical device as prescribed in the MDR (EU 2017/745).

A preferred way to show logical development of a device is to use a risk-based approach, where the device is systematically evaluated to discover potential risks related to the design and how the risks are mitigated. A good tool for assistance is the standard EN ISO 14971 „Medical devices – Application of risk management to medical devices“.

In simple terms, a designer should first try to make the design such that risks are avoided, if that can not be done the user should be protected against the hazardous situation resulting from residual risks and as a final measure, warnings for residual risks should be provided. If there is a residual risk that has not been mitigated to a satisfactory level, a risk-benefit analysis needs to be made showing that the benefits of using the device outweigh the risks involved. All these design decisions should be appropriately documented.

Risk-based approach is a very useful tool as it gives a basis for testing and possibly additional design requirements that may reduce or circumvent a risk. If there is a potential risk, the primary action would be to test if that risk is real. A simple example is that to test if your design is structurally sound you can perform a load test that confirms the status. Of course, the test results need to be documented. In some instances, harmonised standards can be used and in such cases, conformity with the MDR requirements can be assumed, provided that test outcomes are satisfactory. On the other hand, if no harmonised standards exist and then the developer has to select tests to perform and explain why the test method used is appropriate for the purpose. It may also be possible to draw from previous experience if equivalence of devices can be shown.

It is fundamental that a medical device is safe to use but on top of that developers and manufacturers generally want to make claims on performance. Such claims need to be supported by evidence that is collected in a systematic manner. It may be collected in verification or validation activities, through literature or clinical trials as appropriate.

Getting necessary approvals for testing with people can be time consuming so it is advisable to start that work as early as possible and plan the paperwork into the research project timeline. The time it takes to get approvals from ethical boards and authorities can vary but it is not uncommon for the process to take at least 5-6 months. Using the risk-based approach from the early stages of the design process may reduce the time and effort to generate the necessary documentation and may prevent expensive mistakes that otherwise might only be discovered very late in the process.