March 2007

This is the second article in a series of three articles regarding classification of medical devices. As a review, the regulations about medical devices are found in the Code of Federal Regulations Title 21, parts 800-1050. A medical device is distinguished from a drug in that it cannot react chemically with the body and that it is being promoted or studied for a medical purpose.

As mentioned in last month’s article, the FDA has three classifications for devices; I, II, and III. Class I devices were discussed in last month’s article. This month a review of Class II devices will be made.

Class II devices have special restrictions. This includes devices that meet class I restrictions, but require additional standards depending on the type of device. Examples of class II devices includes magnetic resonance imagers and methyl methacrylate for crainioplasty.

The degree of regulation for investigational devices is in direct proportion to the degree of risk. There are three levels of clearance by which a device can be determined for use in research. The first level is through an investigational device exemption (IDE). This is usually required for class II or III devices that pose significant risk of harm and require review and approval from the Food and Drug Administration (FDA) prior to use in research.

The second level is through an exemption from an IDE (an exemption from an exemption?). Devices exempt from the IDE requirements of Part 812 should be justified through reference to one of the exemption categories being claimed. The most common type of device exempt from an IDE is a diagnostic device. ^{[Sec. 812.2(c)(3)]}

The third level is an exemption called an abbreviated IDE. This type of exemption determination is made by the Institutional Review Board (IRB) following receipt of rationale from the sponsor stating why the device is not a significant risk to subjects. If the IRB concurs with the sponsor regarding the non-significant risk assessment, the device does not need regulatory oversight from the FDA.

In summary, a device study requires an IDE or an exemption from the IDE. The sponsor must make the determination regarding the regulatory status and attempt to seek the proper mode of oversight whether through the FDA and the IDE requirements, or through an exemption to the IDE requirements. Knowing the regulatory status will assist the investigator in making the proper request for review from the Institutional Review Board.

See next month’s review of class III devices.

*Heath, E. J. (2006). Research Involving a Medical Device. In E. A. Bankert and R. J. Amdur (Eds.), Institutional Review Board Management and Function (pp. 434-440). Sudbury, MA: Jones and Bartlett.