Medical Device Classification

According to the EU Medical Device Regulation (MDR), medical devices are classified into four classes: I, IIa, IIb, and III. The classification is primarily based on the device's functionality, intended purpose and the associated risk to the patient. Factors such as invasiveness, duration of use, and the part of the body affected influence the classification.

The specific rules and criteria for determining the correct classification of a medical device are outlined in Annex VIII of the MDR. This annex provides detailed guidelines on how to apply the classification rules to different types of devices, taking into account various factors such as the device's intended use, materials, and intended duration of contact with the human body.

As as addition to the MDR there are MDCG guidance’s that will help to classify your product correctly. MDR is written with a general language that fits to all products, however, with MDCG guidelines, it is possible to have case-specific guidance for your product.

In the United States, medical devices are classified into three classes: Class I, Class II, and Class III. The classification is primarily determined by the device's intended use, risk to the patient, and controls necessary to provide reasonable assurance of safety and effectiveness. Generally, Class I devices are low-risk, Class II devices are moderate-risk, and Class III devices are high-risk.

The FDA's classification process involves a detailed evaluation of the device and its intended use. While there is no specific annex outlining classification rules as in the EU MDR, the FDA's regulations and guidance documents provide the necessary criteria and procedures for determining the appropriate classification.

Misclassifying a medical device can have severe consequences, including:

• Project Re-Do: If you have identified a lower risk class, you might need to redo the entire verification and validation step, have additional clinical studies etc. This will severely impact project/business finance and timelines.
• Regulatory non-compliance: Failure to meet the requirements of the correct classification. This is considered as a major non-compliance.
• Market access restrictions: Inability to sell or distribute the device in certain markets. Delayed market introductions due to repeating the engineering work. Your notified body can choose to stop the review and this would mean that you lose your review slot-which will delay the project at least some months. 
• Legal liabilities: Potential claims for damages due to product defects or harm to patients.
• Reputational damage: Negative impact on the company's image and credibility.

To avoid these risks, conduct thorough product development, involve regulatory experts, and maintain clear documentation throughout the classification process. Regular reviews and updates to the classification (if your design changes) as needed are also crucial. And last but not least, read (and understand) the regulation and the relevant guidance.