The Evolution of US Medical Device Regulation

Medical devices are regulated according to the same legislation as food and pharmaceuticals, under the general organization of the Food and Drug Administration (FDA). Manufacturers of high-risk devices such as heart valves and intraocular lens transplants have to demonstrate their safety and effectiveness before the devices can enter the market. One drawback is that many companies who develop these devices find the regulatory process to be very conservative, risk-averse, slow, and expensive. Other organizations concerned with medical practice such as the National Academy of Medicine argue that the current pre-marketing procedures of the FDA are not comprehensive enough. Many devices are cleared for marketing because they are proven to be "substantially similar" to devices already on the market. 

History of FDA Regulation

The FDA began reviewing food and drugs in 1906 under the original Pure Foods and Drugs Act and gradually added biological products and medical devices as well as radiation-emitting products. Congress continued to expand the purview of the FDA in protecting and promoting drugs, biological products, and medical devices.

The development of the regulatory function of the FDA proceeded according to the following timeline.

• 1906 - The Pure Foods and Drugs Act established the organization of the FDA.
• 1938 - The first statute authorizes the FDA to regulate medical products.
• 1944 - The FDA began certifying laboratories and expanded its oversight of biological products.
• 1968 - The Radiation Control for Health and Safety Act created performance standards for radiation-emitting products and regulated exposure to electronic product radiation and intense magnetic fields.
• 1970 - The study of medical device regulation began under Dr. Theodore Cooper's committee. The outlines of the risk-based classification of medical devices were introduced.
• 1976 - The Medical Device Amendments to the FDA's primary authority to regulate medical devices were written. These rules require the FDA to obtain "reasonable assurance of safety and effectiveness" before marketing medical devices.
• 1982 - The organizational units of the FDA that regulate medical devices and radiation-emitting devices merged to form the Center for Devices and Radiological Health.

This legislation evolved through several updates, including a Medical User Fee and Modernization Act of 2002. This modernization act established user fees for application reviews and set performance targets to keep review times reasonable.

Device Classification

The way the FDA's review works is fairly simple. Each device is classified into one of three classes. The classes are be based on the risk associated with the device.

• Class 1 devices include low-risk devices such as stethoscopes. These devices are tested only in a general way. Tests of sterility may be performed.
• Class 2 devices such as cat scan devices have to meet the general control standards like Class 1 devices and "special controls" as well. There may be additional labeling requirements. Class 2 devices are generally passed on the basis of the "510(k) review pathway." They pass the standard because they are similar enough to a previously cleared device that they don't need to be separately tested.
• Class 3 devices usually sustain or support life, are implanted, or present potential unreasonable risk of illness or injury. They have the toughest
  regulatory controls. Most of these devices require Premarket Approval because general and special controls alone cannot reasonably assure their
  safety and effectiveness. A very small number of Class 3 devices that are used to treat small patient populations (fewer than 4,000 patients) can get a "Humanitarian Device Exemption" and be approved on the basis of "probable benefits."

The actual testing capacity of the FDA is comparatively weak. It is focused on getting medical devices to market as quickly as possible. The FDA relies on the sites that make use of these devices to report any adverse events to the FDA and the manufacturer. These reports are stored in a searchable database for public review. According to the Safe Medical Devices Act of 1990, The FDA began post-market surveillance, conducting inspections and requiring manufacturers of high-risk devices to conduct post-approval studies which could trigger recalls.