Any medical device approved by the FDA is grouped into three broad classes, Class I, II, or III, depending on the new device's risk, invasiveness, and impact on the patient's overall health.
The Medical Device Amendments of 1976 to the Federal Food, Drug, and Cosmetic Act established three regulatory classes for medical devices.
The medical device class is a major determining factor for the optimal path to market. The differences between medical devices classified as Class I, II, or III by the FDA is mostly risk, amount of contact with a patient and their internal systems, and whether a device is critical to sustaining life. The classes are as follows:
Class I medical devices are those devices that have a low to moderate risk to the patient and/or user. In general, Class I devices do not come into contact with a patient's internal organs, the central nervous system, or the cardiovascular system. Examples include, elastic bandages, manual stethoscopes, and non-electric wheelchairs.
Class II medical devices are those devices that have a moderate to high risk to the patient and/or user, these devices present a higher category of risk because they are more likely to come into sustained contact with a patient's internal organs. Examples of Class II devices are blood transfusion kits, catheters and some pregnancy test kits.
Class III medical devices are those devices that have a high risk to the patient and/or user; they usually sustain or support life, are implanted, or present potential unreasonable risk of illness or injury. Examples of Class III devices include implantable pacemakers and high-frequency ventilators.
Class I devices are subject to far fewer regulatory requirements than Class II or III devices. If a device falls into a generic category of exempted Class I devices, a premarket notification (510(k)) application and FDA clearance is not required before marketing the device. However, the manufacturer is required to register their establishment and list their generic product with the FDA. Most class I and some class II devices are exempt from review if they are extremely low risk or very similar to existing devices. If a class II device is not exempt it will usually undergo a 510(k) review. 510k review focuses on determining whether the new device is “substantially equivalent” to an already approved device. 510(k) reviews usually do not require clinical trials to demonstrate substantial equivalence. Manufacturers of class III devices will need to submit a premarket approval application, the FDA will review the results of clinical studies in said application and decide whether the new device is safe and effective.
Today, 47% of medical devices are considered Class I and 95% of these devices are exempt from the regulatory process. Following, 43% of medical devices are considered Class II and roughly 10% are considered Class III.
Manufacturers can receive a formal device determination or classification from the FDA by submitting a 513(g) request.
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