What is a Class III medical device?

There are three classes of medical devices in the United States, all regulated by the Food and Drug Administration (FDA). Class III devices have the highest risk profile and therefore have the most significant regulatory requirements. In the United States, a Class III device is also a device that has no substantial equivalence to an existing Class I or II device. This means that if there is no device with similar intended use and indications for use, or if the device is using novel technology, it will be classified as Class III by default. To find substantially equivalent devices, use the FDA’s product classification database. Because medical device classification in the U.S. also depends on risk level, there are exceptions for novel devices with lower risk profiles (see De Novo classification process).

Examples of Class III medical devices

Class III devices “usually sustain or support life, are implanted, or present potential unreasonable risk of illness or injury.” Only 10% of medical devices marketed in the U.S. fall under this category.

Examples of Class III devices include:

• Pacemakers
• Implanted prosthetics
• Cochlear implants
• Defibrillators
• Software defined as a medical device (Software as a Medical Device or SaMD), which meets the risk profile of a Class III device. This may include diagnostic software that is using imaging to identify conditions that, if misdiagnosed, would pose a risk to the patients health or life.

FDA regulatory approval process for Class III medical devices

Almost all Class III medical devices in the United States require premarket approval (PMA) from the FDA before being marketed. Due to the high risk profile of Class III devices, the PMA process requires significant data to demonstrate the safety and efficacy of the device. Unlike Class II devices which require a 510(k) premarket notification, the PMA process requires a thorough review by the FDA that results in their approval of the product for entry into the U.S. market.

The PMA process is defined in Title 21 Code of Federal Regulations (CFR) Part 814 and a full overview of the process is included in our Beginner’s Guide to the FDA PMA Submission Process. A PMA will almost always require:

• Substantial clinical trial data.
• A fully documented quality system compliant with design controls as defined in 21CFR Part 820.
• Documented conformance to recognized consensus standards.
• Detailed descriptions of the device and all of its components.
• Product samples and/or the ability for the FDA to examine the device on-site.

Note that there are exceptions to PMA requirements, most notably the humanitarian device exemption, designed to encourage investment in devices that would serve a small population. See the FDA’s Acceptance and Filing Reviews for Premarket Approval Applications (PMAs) for more information.

Post-market compliance for Class III medical devices

Medical device manufacturers and distributors must also conform with specific requirements once a product is being sold in the market. These requirements include:

• Mandatory reporting of device issues and adverse events by manufacturers, importers, and device user facilities (such as a hospital) as detailed in the Medical Device Reporting regulation (21 CFR Part 803).
• Tracking systems to support any necessary product recalls as detailed in 21 CFR Part 821.
• Post-approval studies that are required with the approval of a PMA, Humanitarian Device Exemption (HDE), or Product Development Protocol (PDP). Post-approval studies are a condition of approval and are mandatory.

Class III medical devices in other countries

Device classification is different in each country, therefore you should not make any assumptions regarding classification in other countries based on the fact that your device is a Class III device in the United States. Each country with medical device regulations has their own classification scheme that may cause your device to be regulated in a different way. During the initial phase of planning for global commercialization of a product, it is imperative that you consider international regulations, their classification schemes, and the registrations that each country will require.

For additional information on the Class III approval process, read our Beginner’s Guide to the FDA PMA Submission Process.