Clinical Investigation Exemption: When Can You Skip the Study?
I see manufacturers assume they can skip clinical investigation because they have equivalence data or a decades-old device. Then the Notified Body asks for the study anyway. The confusion comes from not understanding that exemption is not automatic—it requires documented justification that satisfies four distinct scenarios under MDR Article 61(4).
In This Article
The exemption from clinical investigation is one of the most misunderstood provisions in the MDR. Manufacturers often believe that having a predicate device or sufficient literature is enough to avoid a study. But exemption is not a checkbox. It is a justified position that must be defended through systematic evidence.
The regulatory reality is this: every medical device must comply with general safety and performance requirements. Clinical investigation is the default path to demonstrate that compliance. Exemption is the exception, and exceptions require explicit justification.
MDR Article 61(4) outlines the conditions under which a manufacturer can claim exemption. But reading the article is not enough. The interpretation matters, and the interpretation varies depending on which scenario applies to your device.
The Default Position: Clinical Investigation is Required
Before we discuss exemption, we need to establish the baseline. Article 61(1) states that manufacturers must plan and conduct clinical investigations unless justified otherwise. This means the burden of proof lies with the manufacturer, not the Notified Body.
If your clinical evaluation report does not explicitly address why exemption applies, the Notified Body will assume it does not. This is where many submissions fail. The justification is missing, incomplete, or buried in a section that reviewers do not read carefully.
Exemption is not about avoiding work. It is about demonstrating that additional clinical investigation would not add value because the evidence base is already sufficient. That demonstration must be clear, structured, and traceable.
Exemption from clinical investigation is not a decision—it is a documented justification. If the justification is weak or absent, the Notified Body will require the study regardless of your device history.
Scenario One: Demonstration of Equivalence
This is the most frequently invoked scenario. The manufacturer claims equivalence to a device for which clinical evidence already exists. But equivalence under MDR is not the same as equivalence in conversation. It has a technical definition, and that definition is precise.
MDCG 2020-5 clarifies that equivalence requires three pillars: technical equivalence, biological equivalence, and clinical equivalence. All three must be demonstrated, and the burden of proof increases with risk class.
What I see in practice is partial equivalence. The manufacturer shows technical similarity but does not address biological or clinical differences. Or the predicate device has literature, but the literature does not cover the intended use of the new device. These gaps disqualify the equivalence claim.
Even when equivalence is valid, the exemption is not automatic. You must still show that the existing clinical data for the equivalent device is sufficient to demonstrate compliance for your device. This means the clinical evaluation must assess whether the evidence covers the specific risks, performance claims, and intended use of your device.
If the predicate device has an ongoing PMCF that reveals new risks, your equivalence claim may weaken. If the predicate is being investigated for adverse events, your equivalence becomes a liability, not an asset.
Manufacturers claim equivalence based on technical similarity alone, without addressing biological or clinical equivalence. This fails MDCG 2020-5 and triggers a Notified Body request for clinical investigation.
Scenario Two: State of the Art and Common Clinical Practice
The second scenario applies when the device is part of established clinical practice and its performance characteristics are well known. This is often invoked for Class I or low-risk Class IIa devices.
But
Frequently Asked Questions
What is a Clinical Evaluation Report (CER)?
A CER is a mandatory document under MDR 2017/745 that demonstrates the safety and performance of a medical device through systematic analysis of clinical data. It must be updated throughout the device lifecycle based on PMCF findings.
How often should the CER be updated?
The CER should be updated whenever significant new clinical data becomes available, after PMCF activities, when there are changes to the device or intended purpose, and at minimum during annual reviews as part of post-market surveillance.
What causes CER rejection by Notified Bodies?
Common reasons include inadequate equivalence demonstration, insufficient clinical data for claims, poorly structured SOTA analysis, missing gap analysis, and lack of clear benefit-risk determination. Structure and logical flow are as important as the data itself.
Which MDCG guidance documents are most relevant for clinical evaluation?
Key documents include MDCG 2020-5 (Equivalence), MDCG 2020-6 (Sufficient Clinical Evidence), MDCG 2020-13 (CEAR Template), MDCG 2020-7 (PMCF Plan), and MDCG 2020-8 (PMCF Evaluation Report).
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Peace, Hatem
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