Explore the Changes to Medical Device Classification Under EU MDR

The European Medical Device Regulation (MDR) replaced the Medical Device Directive (MDD) in May of 2017. However, many medical device development companies are still working to understand the key differences between these guiding documents. Fundamentally, the MDR differs from the MDD in terms of device classification. Companies looking to commercialize their products in Europe will need to be familiar with these updated classifications and update their internal manufacturing, testing, and commercialization procedures accordingly. 

All medical devices that carry a CE mark will be required to meet the new EU MDR guidelines, and no devices will be grandfathered in. However, companies with a valid MDD certificate can continue to market their devices (following certain requirements) until the certificate expires or until May 26th, 2024, whichever comes first. 

In this blog, we’ll take you through: 

• EU MDR Device Classifications 
• Overview of products that have been reclassified
• Overview of products that have been classified (and are now subject to regulations) for the first time
• How to determine device classification

Understanding EU MDR Device Classifications

The scope of the MDR is much broader than the MDD. While both documents classify devices based on risk, with higher risk subject to increased regulation and scrutiny, the MDR outlines 22 rules for classification—while the MDD only included 18. Some devices have been reclassified into different risk categories, and some device types have been classified for the first time. In practice, medical device development companies may have to adapt their manufacturing procedures, risk assessment, QMS, and more in order to comply with updated guidance. 

Reclassification of Devices Under MDR

While the MDD focused on the regulations and oversight that would get a product to market in the EU, the MDR expands to consider the full product lifecycle: development, testing, manufacturing, commercialization, efficacy, safety, and long-term use. Due to this increased scope, as well as increased public interest in long-term safety, the MDR takes a more conservative approach to device risk classification. Accordingly, some devices have been reclassified into higher risk categories. Those include: 

• All active implantable devices and their accessories will now be considered Class III
• Any substance-based device intended to be used via a body orifice or applied on the skin may not be Class I (as was the case under MDD), and may be up-classified to Class IIa or IIb
• Certain softwares that are currently covered by Rule 11 may be up-classified
• All non-invasive devices consisting of a substance or a mixture of substances intended to be used in vitro in direct contact with human cells, tissues, or organs taken from the human body, or used in vitro with human embryos before their implantation or administration into the body, are now classified as Class III
• All devices intended specifically for direct contact with the heart or central circulatory system are now Class II (like devices in contact with the central nervous system)
• Breast implants, surgical meshes, and total and partial joint replacements now fall into Class III
• Spinal disc replacement implants or implantable devices that come into contact with the spinal column are now Class III, with some exceptions (screws, wedges, plates, and instruments) 
• Disinfectants and sterilizers fall into Class IIb if they are used for invasive devices and as the end point of processing

If you have questions about what makes a device “active” or “invasive” vs. “non-invasive,” don’t worry. We will cover those terms (and others) later in this blog. 

Perhaps the most impactful change between the MDD and the MDR is that devices with an aesthetic or non-medical purpose have been officially classified and will now be required to adhere to MDR guidance. Annex XVI describes these devices, which include:

1. Contact lenses or other items intended to be introduced into or onto the eye

2. Products intended to be totally or partially introduced into the human body through surgically invasive means for the purpose of modifying the anatomy or fixation of body parts (with the exception of tattooing products and piercings)

3. Substances, combinations of substances, or items intended to be used for facial or other dermal or mucous membrane filling by subcutaneous, submucous, or intradermal injection or other introduction, excluding substances used for tattooing

4. Equipment intended to be used to reduce, remove, or destroy adipose tissue, such as equipment for liposuction, lipolysis, or lipoplasty

5. High-intensity electromagnetic radiation (e.g. infrared, visible light, and ultraviolet)-emitting equipment intended for use on the human body, including coherent and non-coherent sources, monochromatic, and broad spectrum, such as lasers and intense pulsed light equipment, for skin resurfacing, tattoo or hair removal, or other skin treatment

6. Equipment intended for brain stimulation that applies electrical currents or magnetic or electromagnetic fields that penetrate the cranium to modify neuronal activity in the brain

New EU MDR Classification Rules

The MDR classification rules determine which of four risk classes a device falls into. The MDR adds four new rules to the list previously upheld under the MDD.

Rule 19:

All devices incorporating or consisting of nanomaterial are classified as Class III if they present a high or medium potential for internal exposure, Class IIb if they present a low potential for internal exposure, and Class IIa if they present a negligible potential for internal exposure.

Nanomaterials are generally defined as natural, incidental, or manufactured materials containing particles in an unbound state, as an aggregate, or as an agglomerate and where, for 50% or more of the particles in the number size distribution, one or more external dimensions is in the size range of 1-100nm. Example devices classified according to Rule 19 could include wound care products, catheters, dental crowns, and more. 

Rule 20:

All invasive devices with respect to body orifices, other than surgically invasive devices, which are intended to administer medicinal products by inhalation are classified as Class IIa, unless their mode of action has an essential impact on the efficacy and safety of the administered medicinal product or they are intended to treat life-threatening conditions, in which case they are classified as Class IIb. 

Example devices classified according to Rule 20 could include various types of asthma inhalers.

Rule 21:

Devices that are composed of substances or of combinations of substances that are intended to be introduced into the human body via a body orifice or applied to the skin and that are absorbed by or locally dispersed in the human body are classified as:

• Class III if they, or their products of metabolism, are systemically absorbed by the human body in order to achieve the intended purpose

• Class III if they achieve their intended purpose in the stomach or lower gastrointestinal tract and they, or their products of metabolism, are systemically absorbed by the human body

• Class IIa if they are applied to the skin or if they are applied in the nasal or oral cavity as far as the pharynx, and achieve their intended purpose on those cavities
• Class IIb in all other cases

Example devices classified according to Rule 21 could include saline solution nasal sprays, some wart removers, wound protection creams for minor skin irritations, and more.

Rule 22:

Active therapeutic devices with an integrated or incorporated diagnostic function which significantly determines the patient management by the device, such as closed loop systems or automated external defibrillators, are classified as Class III. 

Example devices classified according to Rule 22 include automatic external defibrillators (AEDs), or closed loop systems used to continuously monitor biological conditions in real time and then adjust a therapy in order to maintain or achieve a particular physiological state. For example, an artificial pancreas that links continuous glucose monitoring with an insulin pump for real-time results would fall into this category.

.

Determine Your Device Classification

Determining your medical device classification may feel challenging, particularly with the new rules and up-classifications that have taken effect under MDR. However, classifying your device is ultimately a matter of four things: 

1. Understanding whether your device is invasive, non-invasive, or active

2. Understanding its duration of use

3. Familiarizing yourself with the four class systems that govern all medical devices under the MDR. 

4. Reviewing each of the 22 rules in Annex VIII to determine which one applies to your device

Once you understand these definitions and risk classifications, the rules in Annex VIII can be used to determine what class of device you have under MDR.

Invasive, Non-Invasive, and Active Devices

An invasive medical device is true to its name: it refers to a device which, in whole or in part, penetrates inside the body through a natural opening (like the nose) or through the surface of the body. A device is surgically invasive if it penetrates the body through its surface, with the aid or in the context of a surgical operation. 

A non-invasive medical device does not require or involve a break in the skin. This type of device has no contact with the mucous membrane or the internal body cavity other than through a natural or artificial body orifice. 

An active medical device is a device with operations that depend on a source of electrical energy or any source of power other than that generated directly by the human body (or gravity) and which acts by converting this energy. 

Duration of Use

“Duration of use” refers to the time in which a medical device is used for its intended purpose. There are three categories of duration: 

1.Transient: intended for continuous use for less than 60 minutes
2. Short-term: intended for continuous use for between 60 minutes and 30 days
3.Long-term: intended for continuous use for more than 30 days

EU MDR Class Definitions

Ultimately, medical devices regulated under the MDR fall into one of four classes. The higher the class, the higher the device’s risk—and the more rules and regulations that device’s developer must comply with. 

1. Class I - low risk
2. Class IIa - medium risk
3. Class IIb - medium/high risk
4. Class III - high risk

.